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The association of DNA repair gene polymorphisms with the development and progression of renal cell carcinoma
original article
Annals of Oncology 18: 1817–1827, 2007 doi:10.1093/annonc/mdm337 Published online 21 August 2007
The association of DNA repair gene polymorphisms with the development and progression of renal cell carcinoma S. Sakano1, Y. Hinoda2, N. Okayama2, Y. Kawai1, Y. Korenaga1, S. Eguchi1, K. Nagao1, C. Ohmi1 & K. Naito1* 1
Department of Urology; 2Department of Laboratory Medicine, Graduate School of Medicine, Yamaguchi University, Ube, Japan
Received 8 February 2007; revised 14 May 2007; accepted 25 May 2007
introduction The complex system of DNA repair enzymes plays a vital role in protecting the genome from the consequences of exogenous and endogenous mutagenic exposure [1]. There are at least four known pathways of DNA repair: base excision repair (BER), nucleotide excision repair (NER), double-strand break (DSB; including homologous recombination and non-homologous end-joining) repair and mismatch repair, which operate on specific types of damaged DNA with each involving numerous molecules [2]. There are several common polymorphisms in genes encoding DNA repair enzymes and some of these polymorphisms are reported to result in subtle structural alterations of the repair enzyme and modulation of the repair capacity. The wild-type and variant genotypes of xeroderma pigmentosum complementation groups C (XPC), D (XPD) and G (XPG), and X-ray repair cross-complementing groups 1 (XRCC1) and 3 (XRCC3) have been shown to be associated with different levels of DNA repair activity using various assays. In this manner, these polymorphisms may contribute to *Correspondence to: Professor Katsusuke Naito, Department of Urology, Graduate School of Medicine, Yamaguchi University, 1-1-1 Minami-Kogushi, Ube, Yamaguchi 755-8505, Japan. Tel: +81-836-22-2275; Fax: +81-836-22-2276; E-mail: [email protected]
ª 2007 European Society for Medical Oncology
interindividual variability in DNA damage repair in the general population [3–8]. In addition, significant associations between the polymorphisms in DNA repair genes and the individual risks for different types of cancer have been reported [2, 9]. Risk factors for renal cell carcinoma (RCC) include cigarette smoking, obesity, history of kidney stones and infection, hypertension and treatment of hypertension with thiazide diuretics [10, 11]. Some of the DNA damage that may occur as a result of these factors would be repaired by DNA repair enzymes. Cigarette smoking is considered the main risk factor for RCC and cigarette smoke contains many known carcinogens. Some of these carcinogens form bulky adducts on DNA that are repaired by the NER pathway [12]. Cigarette smoke is also a rich source of reactive oxygen species (ROS) [13], which can induce base damage, single-strand breaks (SSBs) and DSBs. ROS-induced base damage and SSBs are repaired via the BER pathway, while DSBs can be repaired by either homologous recombination repair or non-homologous end-joining. It is therefore thought that functional polymorphisms in DNA repair genes may be associated with increased individual risk for RCC, as in lung or bladder cancer [2, 9]. In addition, we previously reported associations between some DNA repair gene polymorphisms and tumor stage, grade, p53 alteration or
original article
carcinoma (RCC), including smoking. DNA repair gene polymorphisms modulate the repair capacity and might influence individual risk and progression of RCC. We examined associations between functional polymorphisms and risk, clinicopathologic characteristics and survival of RCC. Patients and methods: The study groups comprised 215 RCC patients and 215 age- and gender-matched healthy controls. Polymorphisms in xeroderma pigmentosum complementation groups C, D and G and X-ray repair crosscomplementing groups 1 and 3 genes were genotyped. Results: No significant differences in DNA repair genotype were observed between RCC cases and controls. In all patients, however, greater numbers (‡3) of total variant alleles in all DNA repair genes studied were associated with less frequent venous extension (P = 0.0079). In smokers, some genotypes were associated with characteristics of RCC (Ps £ 0.0067) and smokers with greater numbers of total variant alleles had improved overall survival (P = 0.040). Conclusion: These results suggest that DNA repair gene polymorphisms may not influence RCC susceptibility, but that some of them may influence RCC progression, especially in smokers, possibly due to altered DNA repair capacity by these polymorphisms. Key words: disease progression, DNA repair, genetic polymorphism, renal cell carcinoma, smoking, survival
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Background: DNA repair enzymes repair some of the DNA damage associated with risk factors for renal cell
original article
patients and methods patients and control subjects The ethical review committee of the Graduate School of Medicine, Yamaguchi University approved this study. Between October 1992 and November 2004, 215 consecutive patients with histopathologically confirmed RCC based on the Union Internationale Contre le Cancer (UICC) and American Joint Committee for Cancer (AJCC) classification (1997) underwent radical or partial nephrectomy at Yamaguchi University Hospital, Yamaguchi, Japan. The 215 age- and gender-matched healthy volunteers were chosen from the same geographical area as the control subjects. The age of each control was matched to within 62 years of the age of each RCC patient. The mean ages of the patient at initial diagnosis and control groups were 63.7 years (range 29–87) and 64.2 years (range 29–87), respectively. Data on Eastern Cooperative Oncology Group performance status (ECOG PS) were only available for 91 RCC patients (PS 0 in 68, PS 1 in 13, PS 2 in 7 and PS 3 in 3 patients). Therefore, we could not analyze the polymorphisms in the subgroups validated for ECOG PS [19]. History of smoking status was obtained from RCC patients through interviews with doctors or nurses, and reviewed by the researchers. For the controls, only age and gender were recorded as personal data. The characteristics of the RCC patients and control subjects, all of whom were native Japanese, are shown in Table 1. All patients underwent chest X-rays, computed tomography (CT) scans and bone scans, and were staged according to the TNM staging system of the UICC (1997). Positive for venous extension was defined as tumor extending grossly into the renal vein or vena cava. Well, moderately and poorly differentiated tumors were histopathologically graded as G1, G2 and G3, respectively, based on the UICC classification (1997). After their operation, patients were followed up by chest X-rays, CT scans and bone scans every 6 months. The median duration of follow-up was 49 months (range 0–160). Of the 180 patients who achieved a state of no evidence of disease after the operation (excluding 34 patients with distant metastasis at the time of diagnosis and one patient with unknown disease status), 40 (22.2%) had local
1818 | Sakano et al.
recurrence or distant metastasis during the follow-up. Out of a total of 215 patients, 58 suffered death from any cause during the follow-up.
DNA extraction and genotyping Peripheral blood samples were collected from each patient and each control subject, and lymphocyte DNA was extracted using the QIAamp DNA Mini Kit (VWR International, West Chester, PA, USA). Polymorphisms in XPC (Lys939Gln, A/C), XPD (Lys751Gln, A/C), XPG (Asp1104His, G/C), XRCC1 (Arg399Gln, G/A) and XRCC3 (Thr241Met, C/T) genes were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The method, including primer sequences and restriction endonucleases for each polymorphism, has been described previously [9, 15]. Briefly, the DNA fragments were amplified from 10 ng of DNA in 10 ll PCR reactions containing 1.5 mM MgCl2, 0.2 mM each dNTP, 0.3 U AmpliTaq Gold DNA polymerase (Applied Biosystems, Foster City, CA, USA) and 0.3 lM of each primer. The PCR products were digested with the appropriate restriction endonucleases that recognized and cut either wild-type or variant sequences at 37C for at least 3 h. The digested PCR products were electrophoresed on 2% agarose gels and stained with ethidium bromide for visualization under ultraviolet (UV) light. In order to control the restriction digestion of the PCR products, genotyping assays were randomly repeated and results were checked for concordance. About 10% of the amplified fragments were also randomly checked by direct DNA sequencing and comparison of the PCR-RFLP and sequencing results showed 100% concordance in all experiments [20]. Variant alleles were defined as C for XPC, C for XPD, C for XPG, A for XRCC1 and T for XRCC3 according to previous reports [7, 9].
statistical analysis Differences in genotype and allele frequencies of the DNA repair genes between the RCC cases and the control subjects, and associations between the genotypes and the clinicopathologic characteristics at the time of diagnosis of the RCC patients, were assessed for statistical significance using the chi-square test or two-sided Fisher’s exact test; odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. P values < 0.01 were considered to indicate statistical significance in these tests because multiple comparisons were conducted. The combined XPD and XRCC1 genotype was analyzed as a variable. As both XPD and XRCC1 genes are located close to each other at 19q13.2–13.3 [21], analysis of the combined XPD and XRCC1 genotype could be meaningful with regard to a specific haplotype. In addition, because the prognosis of cancer patients is likely to involve multistep, multigenic pathways, it is unlikely that any one single genetic polymorphism would have a dramatic effect on clinical outcome, and it is important to take a pathway-based analysis of multiple polymorphic genes [22]. Thus, we also analyzed the number of total variant alleles in all DNA repair genes studied. Overall survival of the RCC patients was calculated from the day of nephrectomy until the last follow-up or death from any cause; patients who were alive at the last follow-up were censored at that time. The association between each DNA repair genotype and overall survival was estimated by calculating the risk ratios (RRs) with 95% CIs using Cox’s proportional hazard regression models. In addition, overall survival was analyzed by plotting Kaplan–Meier curves and the survival probability distributions were compared using the log-rank test. P values < 0.05 were considered to indicate statistical significance in these tests. Data were processed using JMP software (SAS Institute Inc., Cary, NC, USA).
results genotype and allele frequencies of the DNA repair genes in the RCC cases and the control subjects Genotype frequencies of the XPC, XPD, XPG, XRCC1 and XRCC3 genes in the 215 RCC cases and 215 age- and
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prognosis in patients with bladder cancer [14–16]. These polymorphisms may also influence malignant phenotypes of RCC due to the modulated DNA repair capacity and subsequent alterations of other cancer-related genes. In the present study, we hypothesized that functional DNA repair gene polymorphisms might be related to individual susceptibility to RCC and its progression. Using a case–control study in the Yamaguchi region, Japan, we tested whether polymorphisms in the DNA repair genes XPC (Lys939Gln, A/C), XPD (Lys751Gln, A/C) and XPG (Asp1104His, G/C) (involved in NER), XRCC1 (Arg399Gln, G/A) (involved in BER) and XRCC3 (Thr241Met, C/T) (involved in DSB repair) were associated with individual risk of RCC. These polymorphisms were generally selected according to prior data on functional effect or reports of association with malignancies, to increase the likelihood of positive findings [2, 7, 17], and we have consecutively investigated the effects of these polymorphisms on cancer biology [9, 14–16]. To date, there has been only one report of a case–control study on the association between DNA repair gene polymorphisms and individual risk of RCC, studied in the Shimane region, Japan by our group [18]. In the current study, the number of cases is approximately twice that in the previous study. Finally, we examined possible associations between the polymorphisms and clinicopathologic characteristics and overall survival of RCC patients.
Annals of Oncology
original article
Annals of Oncology
Table 1. Clinicopathologic characteristics of the renal cell carcinoma patients and control subjects
Age (years) Gender Smoking status
Primary tumor
Distant metastasis
Venous extension Stage grouping
Histopathologic grading
Histopathologic subtype
gender-matched control subjects were found to be in Hardy–Weinberg equilibrium. The genotype frequencies in the 118 non-smokers and 86 smokers with RCC were also in Hardy–Weinberg equilibrium. No significant associations were detected between the genotypes and age, gender, smoking status or tumor grade. The genotype and allele frequencies in cases and controls are shown in Table 2. The AC and AC + CC genotypes of the XPD gene were less frequent in cases than in controls (OR 0.42, 95% CI 0.19–0.95, P = 0.032 and OR 0.41, 95% CI 0.19–0.88, P = 0.019; respectively; chi-square test). The C alleles of the XPD gene were also less frequent in cases than in controls (OR 0.41, 95% CI 0.20–0.84, P = 0.012; chi-square test). However, these differences were not considered statistically significant because multiple comparisons were conducted. No significant differences in genotype or allele frequencies between cases and controls
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Controls, n (%)
63.7 6 12.2 29–87 148 (68.8) 67 (31.2) 118 (54.9) 86 (40.0) 15 (7.0) 66 (30.7) 5 (2.3) 11 (5.1) 116 (54.0) 28 (13.0) 69 (32.1) 1 (0.5) 1 (0.5) 196 (91.2) 8 (3.7) 8 (3.7) 3 (1.4) 180 (83.7) 34 (15.8) 1 (0.5) 167 (77.7) 48 (22.3) 108 (50.2) 25 (11.6) 41 (19.1) 41 (19.1) 32 (14.9) 140 (65.1) 35 (16.3) 8 (3.7) 205 (95.3) 3 (1.4) 3 (1.4) 1 (0.5) 3 (1.4)
64.2 6 12.5 29–87 148 (68.8) 67 (31.2)
were observed for other polymorphisms in the XPC, XPG, XRCC1 or XRCC3 genes.
association between DNA repair genotypes and characteristics of RCC in all patients Associations between the DNA repair genotypes and primary tumor stage, distant metastasis at the time of diagnosis, venous extension and stage grouping of RCC in all patients are presented in Table 3. Venous extension was significantly less frequent in patients with greater numbers of total variant alleles in all DNA repair genes studied than in those with smaller ones (‡3 compared with <3, OR 0.41, 95% CI 0.21–0.80, P = 0.0079; chi-square test). There were no significant associations between DNA repair genotypes and primary tumor stage, distant metastasis at the time of diagnosis, stage grouping or histopathologic grading in all patients.
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Regional lymph nodes
Mean 6 SD Range Men Women Non-smoker Smoker <20 pack-years ‡20 pack-years Unknown pack-years Unknown pT1 pT2 pT3 pT4 pTX N0 N1 N2 NX M0 M1 MX Negative Positive Stage I Stage II Stage III Stage IV G1 G2 G3 GX Clear cell renal carcinoma Papillary renal carcinoma Chromophobe renal carcinoma Collecting duct carcinoma Renal cell carcinoma, unclassified
Cases, n (%)
original article
Annals of Oncology
Table 2. Genotype and allele frequencies of DNA repair genes in renal cell carcinoma cases and controls Genotype/allele
Cases, n (%)
Controls, n (%)
OR (95% CI)
XPC (Lys939Gln, A/C)
AA AC CC AC + CC A allele C allele AA AC CC AC + CC A allele C allele GG GC CC GC + CC G allele C allele GG GA AA GA + AA G allele A allele CC CT TT CT + TT C allele T allele
81 97 37 134 259 171 205 9 1 10 419 11 50 93 72 165 193 237 125 81 9 90 331 99 174 38 3 41 386 44
70 114 31 145 254 176 192 20 3 23 404 26 51 99 65 164 201 229 120 85 10 95 325 105 173 33 5 38 379 43
1.00 0.74 1.03 0.80 1.00 0.95 1.00 0.42 0.31 0.41 1.00 0.41 1.00 0.96 1.13 1.03 1.00 1.08 1.00 0.92 0.86 0.91 1.00 0.93 1.00 1.15 0.60 1.07 1.00 1.01
XPD (Lys751Gln, A/C)
XPG (Asp1104His, G/C)
XRCC1 (Arg399Gln, G/A)
XRCC3 (Thr241Met, C/T)
(37.7) (45.1) (17.2) (62.3) (60.2) (39.8) (95.3) (4.2) (0.5) (4.7) (97.4) (2.6) (23.3) (43.3) (33.5) (76.7) (44.9) (55.1) (58.1) (37.7) (4.2) (41.9) (77.0) (23.0) (80.9) (17.7) (1.4) (19.1) (89.8) (10.2)
(32.6) (53.0) (14.4) (67.4) (59.1) (40.9) (89.3) (9.3) (1.4) (10.7) (94.0) (6.0) (23.7) (46.0) (30.2) (76.3) (46.7) (53.3) (55.8) (39.5) (4.7) (44.2) (75.6) (24.4) (82.0) (15.6) (2.4) (18.0) (89.8) (10.2)
(reference) (0.48–1.12) (0.58–1.83) (0.54–1.19) (reference) (0.73–1.25) (reference) (0.19–0.95) (0.03–3.03) (0.19–0.88) (reference) (0.20–0.84) (reference) (0.59–1.55) (0.68–1.89) (0.66–1.60) (reference) (0.82–1.41) (reference) (0.62–1.36) (0.34–2.20) (0.62–1.33) (reference) (0.68–1.27) (reference) (0.69–1.91) (0.14–2.53) (0.66–1.75) (reference) (0.65–1.57)
P valuea 0.15 0.92 0.27 0.73 0.032 0.36 0.019 0.012 0.86 0.64 0.91 0.58 0.66 0.81 0.63 0.63 0.60 0.72 0.78 0.98
a
Chi-square test or two-sided Fisher’s exact test. OR, odds ratio; CI, confidence interval.
association between DNA repair genotypes and characteristics of RCC in non-smokers Associations between the DNA repair genotypes and characteristics of RCC in non-smokers are presented in Table 4. The DNA repair genotypes were not significantly associated with primary tumor stage, distant metastasis at the time of diagnosis, venous extension, stage grouping or histopathologic grading in non-smokers. association between DNA repair genotypes and characteristics of RCC in smokers Although smoking data for current or former smoking status were not completely available for all smokers, the number of former smokers was relatively small. In addition, the subgroups divided by pack-years of cigarette consumption are likely to have more chances for statistical significance due to the small numbers. The current and former smokers were therefore analyzed as one group irrespective of pack-years. Associations between the DNA repair genotypes and primary tumor stage, distant metastasis at the time of diagnosis, venous extension and stage grouping of RCC in smokers are presented in Table 5.
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Combined genotypes with at least one variant allele in XPD or XRCC1 were significantly less frequent in patients with pT2, pT3 or pT4 tumors than in those with pT1 (OR 0.24, 95% CI 0.096–0.62, P = 0.0023; chi-square test). Distant metastasis at the time of diagnosis was significantly less frequent in patients with CC genotypes of the XPG gene than in those with GG + GC (OR 0.091, 95% CI 0.011–0.73, P = 0.0067; two-sided Fisher’s exact test). In addition, both GA + AA genotypes of the XRCC1 and genotypes with at least one variant allele in XPD or XRCC1 were significantly less frequent in patients with stage groupings II, III or IV than in those with stage grouping I (OR 0.24, 95% CI 0.096–0.62, P = 0.0023 and OR 0.18, 95% CI 0.071–0.46, P = 0.00023; respectively; chi-square test). There were no significant associations between DNA repair genotypes and venous extension or histopathologic grading in smokers.
DNA repair genotypes and RCC patients’ survival Cox’s proportional hazard regression analysis for DNA repair genotypes influencing overall survival in RCC patients is presented in Table 6. No significant differences were found
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Gene (polymorphism)
doi:10.1093/annonc/mdm337 | 1821
1.00 (reference) 0.91 (0.46–1.81) 0.79 1.00 (reference) 0.59 (0.34–1.01) 0.055 1.00 (reference) 0.61 (0.36–1.05) 0.076
80 (81.6) 18 (18.4) 61 (62.2) 37 (37.8) 55 (56.1) 43 (43.9)
(reference) (1.11–6.51) 0.024 (reference) (0.54–3.39) 0.52
P valuea
(22.2) 10 (29.4) 1.00 (reference) (77.8) 24 (70.6) 0.69 (0.30–1.55) 0.36 (65.0) 25 (73.5) 1.00 (reference) (35.0) 9 (26.5) 0.67 (0.29–1.52) 0.33
89 (49.4) 18 (52.9) 1.00 (reference) 91 (50.6) 16 (47.1) 0.87 (0.42–1.81) 0.71
82 (45.6) 13 (38.2) 0.74 (0.35–1.57) 0.43
98 (54.4) 21 (61.8) 1.00 (reference)
147 (81.7) 26 (76.5) 1.00 (reference) 33 (18.3) 8 (23.5) 1.37 (0.57–3.30) 0.48
103 (57.2) 22 (64.7) 1.00 (reference) 77 (42.8) 12 (35.3) 0.73 (0.34–1.56) 0.42
40 140 117 63
(38.3) (61.7) (82.6) (17.4)
(21.6) (78.4) (62.9) (37.1)
75 (44.9) 92 (55.1)
78 (46.7)
89 (53.3)
129 (77.3) 38 (22.8)
93 (55.7) 74 (44.3)
36 131 105 62
161 (96.4) 6 (3.6)
64 103 138 29
(35.4) (64.6) (83.3) (16.7)
(29.2) (70.8) (79.2) (20.8)
32 (66.7) 16 (33.3)
18 (37.5)
30 (62.5)
45 (93.8) 3 (6.3)
32 (66.7) 16 (33.3)
14 34 38 10
44 (91.7) 4 (8.3)
17 31 40 8
Venous extension, n (%) Negative Positive (reference) (0.58–2.21) 0.71 (reference) (0.40–2.25) 0.91
P valuea
(reference) (0.32–1.38) 0.27 (reference) (0.21–0.96) 0.035
1.00 (reference) 0.41 (0.21–0.80) 0.0079c
0.69 (0.35–1.32) 0.26
1.00 (reference)
1.00 (reference) 0.23 (0.067–0.77) 0.011
1.00 (reference) 0.63 (0.32–1.23) 0.17
1.00 0.67 1.00 0.45
1.00 (reference) 2.44 (0.66–9.03) 0.24
1.00 1.13 1.00 0.95
OR (95% CI)
b
Chi-square test or two-sided Fisher’s exact test. For those polymorphisms with few homozygous variant alleles, only the combined results of the heterozygous and homozygous variant alleles are shown. c The bold entry indicates statistical sinificance. OR, odds ratio; CI, confidence interval.
a
1.00 (reference) 0.62 (0.36–1.07) 0.084
63 (64.3) 35 (35.7)
(reference) (0.50–1.79) 0.85 (reference) (0.40–1.27) 0.25
(41.1) 7 (20.6) 1.00 (58.9) 27 (79.4) 2.69 (83.9) 27 (79.4) 1.00 (16.1) 7 (20.6) 1.35
OR (95% CI)
174 (96.7) 31 (91.2) 1.00 (reference) 6 (3.3) 3 (8.8) 2.81 (0.67–11.80) 0.16
74 106 151 29
Distant metastasis, n (%) M0 M1
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Volume 18 | No. 11 | November 2007 (23.5) (76.5) (70.4) (29.6)
1.00 0.94 1.00 0.71
(reference) (0.56–1.69) 0.92 (reference) (0.24–1.07) 0.073
23 75 69 29
1.00 0.97 1.00 0.51
P valuea
1.00 (reference) 0.78 (0.21–2.85) 0.76
(37.8) (62.2) (87.8) (12.2)
OR (95% CI)
94 (95.9) 4 (4.1)
37 61 86 12
Primary tumor, n (%) pT1 pT2/pT3/pT4
XPC (Lys939Gln, A/C) AA 43 (37.1) AC + CC 73 (62.9) AA + AC 91 (78.5) CC 25 (21.6) XPD (Lys751Gln, A/C)b AA 110 (94.8) AC + CC 6 (5.2) XPG (Asp1104His, G/C) GG 26 (22.4) GC + CC 90 (77.6) GG + GC 73 (62.9) CC 43 (37.1) XRCC1 (Arg399Gln, G/A)b GG 61 (52.6) GA + AA 55 (47.4) XRCC3 (Thr241Met, C/T)b CC 93 (80.2) CT + TT 23 (19.8) Combined XPD and XRCC1 XPD AA and 57 (49.1) XRCC1 GG Other 59 (50.9) Total variant alleles <3 51 (44.0) ‡3 65 (56.0)
Genotype
Table 3. Associations between DNA repair genotypes and characteristics of renal cell carcinoma in all patients
(37.0) (63.0) (77.8) (22.2)
41 66 94 13
(38.3) (61.7) (87.9) (12.2)
1.00 0.95 1.00 0.48
(reference) (0.55–1.64) (reference) (0.23–1.01)
OR (95% CI)
0.050
0.85
P valuea
(23.2) (76.9) (63.9) (36.1)
25 82 74 33
(23.4) (76.6) (69.2) (30.8)
1.00 0.99 1.00 0.79
(reference) (0.53–1.86) (reference) (0.45–1.39)
48 (44.4) 59 (55.1) 1.00 (reference) 60 (55.6) 48 (44.9) 0.65 (0.38–1.11)
56 (51.9) 40 (37.4) 0.55 (0.32–0.96)
52 (48.2) 67 (62.6) 1.00 (reference)
90 (83.3) 84 (78.5) 1.00 (reference) 18 (16.7) 23 (21.5) 1.37 (0.69–2.72)
56 (51.9) 69 (64.5) 1.00 (reference) 52 (48.2) 38 (35.5) 0.59 (0.34–1.02)
25 83 69 39
0.12
0.033
0.37
0.060
0.41
0.97
103 (95.4)102 (95.3) 1.00 (reference) 5 (4.6) 5 (4.7) 1.01 (0.28–3.59) >0.99
40 68 84 24
Stage grouping, n (%) I II/III/IV
Annals of Oncology
original article
1.00 (reference) 3.58 (0.36–35.4) 0.34 1.00 0.84 1.00 0.81 1.00 (reference) 0.95 (0.45–1.98) 0.89 1.00 (reference) 1.12 (0.51–2.79) 0.68 1.00 (reference) 1.03 (0.50–2.14) 0.93 1.00 (reference) 0.72 (0.35–1.48) 0.37
(94.6) (5.5) (21.8) (78.2) (72.7) (27.3) (60.0) (40.0) (74.6) (25.5) (56.4) (43.6) (52.7) (47.3)
(41.4) (58.6) (81.8) (18.2)
(19.2) (80.8) (70.7) (29.3)
49 (49.5) 50 (50.5)
44 (44.4)
55 (55.6)
77 (77.8) 22 (22.2)
57 (57.6) 42 (42.4)
19 80 70 29
97 (98.0) 2 (2.0)
41 58 81 18
(22.2) (77.8) (77.8) (22.2)
(27.8) (72.2) (66.7) (33.3)
8 (44.4) 10 (55.6)
6 (33.3)
12 (66.7)
12 (66.7) 6 (33.3)
13 (72.2) 5 (27.8)
5 13 12 6
17 (94.4) 1 (5.6)
4 14 14 4
(reference) (0.76–8.06) 0.19 (reference) (0.38–4.37) 0.74
P valuea
(reference) (0.20–1.94) 0.41 (reference) (0.41–3.52) 0.73
1.00 (reference) 1.23 (0.45–3.36) 0.69
0.63 (0.22–1.80) 0.38
1.00 (reference)
1.00 (reference) 1.75 (0.59–5.20) 0.31
1.00 (reference) 0.52 (0.17–1.58) 0.24
1.00 0.62 1.00 1.21
1.00 (reference) 2.85 (0.25–33.2) 0.40
1.00 2.47 1.00 1.29
OR (95% CI)
(39.0) (61.1) (80.0) (20.0)
(17.9) (82.1) (67.4) (32.6)
41 (43.2) 54 (56.8)
41 (43.2)
54 (56.8)
68 (71.6) 27 (28.4)
55 (57.9) 40 (42.1)
17 78 64 31
94 (99.0) 1 (1.1)
37 58 76 19
(34.8) (65.2) (82.6) (17.4)
(30.4) (69.6) (82.6) (17.4)
16 (69.6) 7 (30.4)
10 (43.5)
13 (56.5)
22 (95.7) 1 (4.4)
15 (65.2) 8 (34.8)
7 16 19 4
20 (87.0) 3 (13.0)
8 15 19 4
Venous extension, n (%) Negative Positive
(reference) (0.18–1.40) (reference) (0.14–1.39)
0.52
0.21
0.18
0.023
1.00 (reference) 0.33 (0.13–0.88)
1.01 (0.40–2.54)
1.00 (reference)
0.023
0.98
1.00 (reference) 0.11 (0.015–0.89) 0.014
1.00 (reference) 0.73 (0.28–1.90)
1.00 0.50 1.00 0.44
P valuea
(reference) (0.46–3.10) 0.71 (reference) (0.26–2.77) >0.99
1.00 (reference) 14.1 (1.39–143)
1.00 1.20 1.00 0.84
OR (95% CI)
b
Chi-square test or two-sided Fisher’s exact test. For those polymorphisms with few homozygous variant alleles, only the combined results of the heterozygous and homozygous variant alleles are shown. OR, odds ratio; CI, confidence interval.
(reference) (0.34–2.07) 0.71 (reference) (0.36–1.79) 0.60
1.00 0.86 1.00 0.55
Distant metastasis, n (%) M0 M1
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a
P valuea
(reference) (0.41–1.82) 0.70 (reference) (0.21–1.41) 0.21
OR (95% CI)
(40.0) (60.0) (85.5) (14.6)
Primary tumor, n (%) pT1 pT2/pT3/pT4
XPC (Lys939Gln, A/C) AA 23 (36.5) 22 AC + CC 40 (63.5) 33 AA + AC 48 (76.2) 47 CC 15 (23.8) 8 XPD (Lys751Gln, A/C)b AA 62 (98.4) 52 AC + CC 1 (1.6) 3 XPG (Asp1104His, G/C) GG 12 (19.1) 12 GC + CC 51 (81.0) 43 GG + GC 43 (68.3) 40 CC 20 (31.8) 15 XRCC1 (Arg399Gln, G/A)b GG 37 (58.7) 33 GA + AA 26 (41.3) 22 XRCC3 (Thr241Met, C/T)b CC 49 (77.8) 41 CT + TT 14 (22.2) 14 Combined XPD and XRCC1 XPD AA and 36 (57.1) 31 XRCC1 GG Other 27 (42.9) 24 Total variant alleles <3 28 (44.4) 29 ‡3 35 (55.6) 26
Genotype
Table 4. Associations between DNA repair genotypes and characteristics of renal cell carcinoma in non-smokers
(37.3) 23 (39.0) (62.7) 36 (61.0) (84.8) 50 (87.9) (15.3) 9 (12.2)
(20.3) (79.7) (71.2) (28.8)
12 47 41 18
(20.3) (79.7) (69.5) (30.5)
28 (47.5) 29 (49.2) 31 (52.5) 30 (50.9)
25 (42.4) 26 (44.1)
34 (57.6) 33 (55.9)
48 (81.4) 42 (71.2) 11 (18.6) 17 (28.8)
35 (59.3) 35 (59.3) 24 (40.7) 24 (40.7)
12 47 42 17
58 (98.3) 56 (94.9) 1 (1.7) 3 (5.1)
22 37 45 14
Stage grouping, n (%) I II/III/IV (reference) (0.44–1.96) (reference) (0.23–1.47)
(reference) (0.41–2.45) >0.99 (reference) (0.49–2.39) 0.84
0.62
0.25
0.85
P valuea
1.00 (reference) 0.93 (0.45–1.92)
1.07 (0.52–2.22)
1.00 (reference)
1.00 (reference) 1.77 (0.74–4.19)
0.85
0.85
0.19
1.00 (reference) 1.00 (0.48–2.08) >0.99
1.00 1.00 1.00 1.09
1.00 (reference) 3.11 (0.31–30.8)
1.00 0.93 1.00 0.58
OR (95% CI)
original article Annals of Oncology
Volume 18 | No. 11 | November 2007
Primary tumor, n (%) pT1 pT2/pT3/pT4
doi:10.1093/annonc/mdm337 | 1823
62 (86.1) 10 (13.9)
41 (56.9) 31 (43.1) 36 (50.0) 36 (50.0)
1.00 (reference) 0.51 (0.14–1.86) 0.36
1.00 (reference) 0.24 (0.096–0.62) 0.0023c 1.00 (reference) 0.48 (0.20–1.14) 0.096
(21.4) (78.6) (78.6) (21.4)
(35.7) (64.3) (92.9) (7.1)
10 (71.4) 4 (28.6)
9 (64.3) 5 (35.7)
12 (85.7) 2 (14.3)
9 (64.3) 5 (35.7)
5 9 13 1
13 (92.9) 1 (7.1)
3 11 11 3
(reference) (0.67–10.2) (reference) (0.40–7.14) 0.44
0.23
P valuea
(reference) (0.15–1.75) 0.32 (reference) (0.011–0.73) 0.0067c
1.00 (reference) 0.40 (0.12–1.39)
1.00 (reference) 0.74 (0.22–2.41)
0.16
0.77
1.00 (reference) 1.03 (0.20–5.32) >0.99
1.00 (reference) 0.87 (0.27–2.87) >0.99
1.00 0.51 1.00 0.091
1.00 (reference) 1.31 (0.14–12.7) >0.99
1.00 2.62 1.00 1.69
OR (95% CI)
(38.1) (61.9) (85.7) (14.3)
(22.2) (77.8) (54.0) (46.0)
30 (47.6) 33 (52.4)
33 (52.4) 30 (47.6)
53 (84.1) 10 (15.9)
36 (57.1) 27 (42.9)
14 49 34 29
59 (93.7) 4 (6.4)
24 39 54 9
(39.1) (60.9) (82.6) (17.4)
(30.4) (69.6) (78.3) (21.7)
16 (69.6) 7 (30.4)
17 (73.9) 6 (26.1)
21 (91.3) 2 (8.7)
17 (73.9) 6 (26.1)
7 16 18 5
22 (95.7) 1 (4.4)
9 14 19 4
Venous extension, n (%) Negative Positive (reference) (0.36–2.55) (reference) (0.35–4.58) 0.74
0.93
P valuea
(reference) (0.22–1.90) (reference) (0.11–0.99)
1.00 (reference) 0.40 (0.14–1.10)
1.00 (reference) 0.39 (0.14–1.11)
1.00 (reference) 0.51 (0.10–2.50)
1.00 (reference) 0.47 (0.16–1.35)
1.00 0.65 1.00 0.33
0.071
0.073
0.50
0.16
0.041
0.43
1.00 (reference) 0.67 (0.071–6.33) >0.99
1.00 0.96 1.00 1.26
OR (95% CI)
b
Chi-square test or two-sided Fisher’s exact test. For those polymorphisms with few homozygous variant alleles, only the combined results of the heterozygous and homozygous variant alleles are shown. c The bold entries indicate statistical significance. OR, odds ratio; CI, confidence interval.
44 (61.1) 28 (38.9)
(22.2) (77.8) (54.2) (45.8)
1.00 (reference) 0.32 (0.13–0.80) 0.014
(reference) (0.31–2.34) 0.80 (reference) (0.23–1.33) 0.18
16 56 39 33
(41.7) (58.3) (86.1) (13.9)
1.00 0.86 1.00 0.55
30 42 62 10
Distant metastasis, n (%) M0 M1
68 (94.4) 4 (5.6)
(reference) (0.42–2.44) 0.98 (reference) (0.13–1.57) 0.24
P valuea
1.00 (reference) 0.26 (0.028–2.46) 0.36
1.00 1.01 1.00 0.44
OR (95% CI)
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Volume 18 | No. 11 | November 2007
a
XPC (Lys939Gln, A/C) AA 17 (37.8) 15 (37.5) AC + CC 28 (62.2) 25 (62.5) AA + AC 36 (80.0) 36 (90.0) CC 9 (20.0) 4 (10.0) XPD (Lys751Gln, A/C)b AA 41 (91.1) 39 (97.5) AC + CC 4 (8.9) 1 (2.5) XPG (Asp1104His, G/C) GG 10 (22.2) 10 (25.0) GC + CC 35 (77.8) 30 (75.0) GG + GC 24 (53.3) 27 (67.5) CC 21 (46.7) 13 (32.5) XRCC1 (Arg399Gln, G/A)b GG 22 (48.9) 30 (75.0) GA + AA 23 (51.1) 10 (25.0) XRCC3 (Thr241Met, C/T)b CC 37 (82.2) 36 (74.6) CT + TT 8 (17.8) 4 (25.5) Combined XPD and XRCC1 XPD AA and XRCC1 GG 19 (42.2) 30 (75.0) Other 26 (57.8) 10 (25.0) Total variant alleles <3 20 (44.4) 25 (62.5) ‡3 25 (55.6) 15 (37.5)
Genotype
Table 5. Associations between DNA repair genotypes and characteristics of renal cell carcinoma in smokers
(35.7) 18 (40.9) (64.3) 26 (59.1) (78.6) 40 (90.9) (21.4) 4 (9.1)
(21.4) (78.6) (50.0) (50.0)
12 32 31 13
(27.3) (72.7) (70.5) (29.5)
17 (40.5) 29 (65.9) 25 (59.5) 15 (34.1)
16 (38.1) 34 (77.3) 26 (61.9) 10 (22.7)
36 (85.7) 38 (86.4) 6 (14.3) 6 (13.6)
19 (45.2) 34 (77.3) 23 (54.8) 10 (22.7)
9 33 21 21
38 (90.5) 43 (97.7) 4 (9.5) 1 (2.3)
15 27 33 9
Stage grouping, n (%) I II/III/IV (reference) (0.34–1.92) (reference) (0.10–1.30)
(reference) (0.27–1.96) (reference) (0.17–1.02)
0.0023c
0.053
0.53
0.20
0.14
0.62
P valuea
1.00 (reference) 0.35 (0.15–0.84)
1.00 (reference) 0.18 (0.071–0.46)
0.018
0.00023c
1.00 (reference) 0.95 (0.28–3.21) >0.99
1.00 (reference) 0.24 (0.096–0.62)
1.00 0.73 1.00 0.42
1.00 (reference) 0.22 (0.024–2.06)
1.00 0.80 1.00 0.37
OR (95% CI)
Annals of Oncology
original article
Volume 18 | No. 11 | November 2007
54 4 16 42 40 18 36 22 50 8 33 25 33 25
204 10 49 165 142 72 124 90 173 41 118 96 106 108
(reference) (0.84–1.46) 0.48 (reference) (0.96–1.78) 0.081
P value
(reference) (0.63–1.13) 0.24 (reference) (0.69–1.21) 0.57
1.00 (reference) 0.85 (0.65–1.10) 0.22
1.00 (reference) 0.97 (0.74–1.26) 0.83
1.00 (reference) 0.75 (0.49–1.06) 0.10
1.00 (reference) 0.90 (0.69–1.18) 0.45
1.00 0.84 1.00 0.92
1.00 (reference) 1.70 (0.93–2.68) 0.077
1.00 1.10 1.00 1.33
RR (95% CI)
57 61
67 51
90 28
70 48
24 94 83 35
114 4
45 73 95 23
18 16
19 15
28 6
21 13
10 24 24 10
31 3
11 23 25 9
Nonsmokers Cases, n Deaths, n (reference) (0.81–1.68) 0.44 (reference) (0.93–2.03) 0.11
P value
(reference) (0.52–1.11) 0.14 (reference) (0.68–1.43) 0.98
1.00 (reference) 0.91 (0.65–1.28) 0.60
1.00 (reference) 1.05 (0.74–1.47) 0.78
1.00 (reference) 0.79 (0.49–1.19) 0.28
1.00 (reference) 0.97 (0.68–1.37) 0.86
1.00 0.75 1.00 1.01
1.00 (reference) 2.05 (1.00–3.46) 0.051
1.00 1.15 1.00 1.40
RR (95% CI)
45 40
49 36
73 12
52 33
20 65 51 34
80 5
32 53 72 13
Smokers Cases, n
b
For those polymorphisms with few homozygous variant alleles, only the combined results of the heterozygous and homozygous variant alleles are shown. The bold entry indicates statistical significance. RR, risk ratio; CI, confidence interval.
20 38 14 44
80 134 37 177
All patients Cases, n Deaths, n
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a
XPC (Lys939Gln, A/C) AA AC + CC AA + AC CC XPD (Lys751Gln, A/C)a AA AC + CC XPG (Asp1104His, G/C) GG GC + CC GG + GC CC XRCC1 (Arg399Gln, G/A)a GG GA + AA XRCC3 (Thr241Met, C/T)a CC CT + TT Combined XPD and XRCC1 XPD AA and XRCC1 GG Other Total variant alleles <3 ‡3
Genotype
Table 6. Cox’s proportional hazard regression analysis for DNA repair genotypes influencing overall survival in renal cell carcinoma patients
15 7
13 9
20 2
14 8
6 16 15 7
21 1
9 13 18 4
Deaths, n (reference) (0.63–1.50) (reference) (0.57–1.74)
(reference) (0.60–1.57) (reference) (0.45–1.14)
0.31
0.11
0.17
0.18
0.79
0.63
0.84
0.86
P value
1.00 (reference) 0.62 (0.37–0.98) 0.040b
1.00 (reference) 0.79 (0.48–1.24)
1.00 (reference) 0.58 (0.23–1.12)
1.00 (reference) 0.72 (0.42–1.15)
1.00 0.94 1.00 0.74
1.00 (reference) 1.31 (0.31–2.96)
1.00 0.96 1.00 1.06
RR (95% CI)
original article Annals of Oncology
Annals of Oncology
original article
between DNA repair genotypes and the probability of overall survival in all RCC patients or in non-smokers. In smokers, however, the number of total variant alleles in all DNA repair genes studied was significantly associated with overall survival (RR 0.62, 95% CI 0.37–0.98, P = 0.040), thus patients with three or more variant alleles had improved overall survival. Overall survival was plotted for total variant alleles (‡3 compared with <3) using Kaplan–Meier survival curves (Figure 1). Patients with three or more variant alleles were significantly associated with improved overall survival compared with the remaining groups in smokers (P = 0.042; log-rank test).
discussion
Volume 18 | No. 11 | November 2007
Figure 1. Kaplan–Meier overall survival curves for renal cell carcinoma patients in smokers stratified by the number of total variant alleles in all DNA repair genes studied (‡3 compared with <3). Patients with three or more variant alleles were significantly associated with improved overall survival compared with the remaining groups in smokers (P = 0.042; logrank test).
induce alteration of other cancer-related genes in tumor cells and subsequently result in cancer progression, since the accumulation of multiple genetic changes causes cancer development and progression. We previously showed a significant association between the DNA repair gene polymorphism and p53 alteration in patients with muscleinvasive bladder cancer [16]. The investigation into the associations between DNA repair gene polymorphisms and major genetic alterations in RCC is currently ongoing in our laboratory to test the above-mentioned hypothesis. In all patients, DNA repair genotypes were only associated with venous extension. Interestingly, no significant association was found between DNA repair genotypes and clinicopathologic characteristics of RCC in non-smokers, while the genotypes were associated with primary tumor stage, distant metastasis at the time of diagnosis and stage grouping in smokers. Furthermore, the number of total variant alleles in all DNA repair genes studied was associated with overall survival in smokers. Smoking is considered the main risk factor for RCC [11]. Cigarette smoke contains thousands of known compounds, many of which are mutagenic, carcinogenic or both [12]. Some of these carcinogens induce DNA adducts or other types of damage to DNA that are repaired by the DNA repair enzymes. If left unrepaired, these DNA lesions may lead to gene mutations. Impaired DNA repair and several DNA repair gene polymorphisms in NER, BER and DSB repair pathways have been reported to be associated with increased susceptibility to some smoking-related cancers [12, 13, 27]. In smokers, therefore, decreased DNA repair capacity by the DNA repair genotypes for carcinogens in cigarette smoke may cause accumulation of genetic alteration and subsequently more aggressive cancer. This explanation is compatible with our results on RCC in smokers. However, the analysis performed in the subgroup of smokers, regarding the prognosis value of the polymorphisms, is controversial because the power of the analysis is limited
doi:10.1093/annonc/mdm337 | 1825
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In this study, we found some significant associations between DNA repair genotypes and characteristics of RCC. This result may be due to the modulated DNA repair capacity by the DNA repair gene polymorphisms. Various assays have been developed to quantify DNA repair activity for DNA repair gene polymorphisms, including the Comet assay and the host cell reactivation assay [4, 23]. Despite some inconsistencies in the literature, it seems likely that the wild-type and variant genotypes are associated with different levels of DNA repair activity [3–7]. In general, our patients with the wild-type genotypes of DNA repair genes studied were likely to have more advanced RCCs. The wild-type genotypes conferring suboptimal DNA repair in the tumor could lead to biologically more aggressive RCC. It has been shown that the wild-type genotypes of XPC, XPD, XPG or XRCC1 are associated with decreased DNA repair capacity [3, 5–7]. These results are in accord with our findings that patients with the wild-type genotypes have more advanced RCCs. In addition, we previously reported that the wild-type genotypes of the same DNA repair genes were associated with shorter disease-specific survival in muscle-invasive bladder cancer patients [15]. However, it was unclear whether this association resulted from original nature of the tumor related to the genotypes or from additional effects of chemoradiotherapy. In our present study, DNA repair gene polymorphisms potentially influenced malignant phenotypes of RCC, although they were germline variations not somatic mutations in tumor cells. Loktionov [24] demonstrated that both cancer initiation risk and later neoplastic events (tumor growth, invasion, metastatic spread, response to therapeutic interventions and, finally, survival) are strongly affected by factors that are predetermined by the individual’s genetic background. Hunter [25] also stated that recent evidence implies a significant role of germline polymorphisms in cancer progression. Germline polymorphisms may play an important role in cancer progression because cancer development and progression strongly depend on altered interactions between malignant cells and their normal neighbors. We previously reported that some vascular endothelial growth factor (VEGF) genotypes might have effects on clinicopathologic characteristics at the time of diagnosis or prognosis of RCC, possibly through altered VEGF expression [26]. Furthermore, the modulated DNA repair capacity by the DNA repair gene polymorphisms might
original article
conflict of interest statement None declared.
1826 | Sakano et al.
acknowledgements This study was supported in part by a Grant-in-Aid for Scientific Research (C) (19591853) from the Japan Society for the Promotion of Science.
references 1. Hoeijmakers JH. Genome maintenance mechanisms for preventing cancer. Nature 2001; 411: 366–374. 2. Goode EL, Ulrich CM, Potter JD. Polymorphisms in DNA repair genes and associations with cancer risk. Cancer Epidemiol Biomarkers Prev 2002; 11: 1513–1530. 3. Lunn RM, Helzlsouer KJ, Parshad R et al. XPD polymorphisms: effects on DNA repair proficiency. Carcinogenesis 2000; 21: 551–555. 4. Spitz MR, Wu X, Wang Y et al. Modulation of nucleotide excision repair capacity by XPD polymorphisms in lung cancer patients. Cancer Res 2001; 61: 1354–1357. 5. Cornetta T, Festa F, Testa A, Cozzi R. DNA damage repair and genetic polymorphisms: assessment of individual sensitivity and repair capacity. Int J Radiat Oncol Biol Phys 2006; 66: 537–545. 6. Naccarati A, Soucek P, Stetina R et al. Genetic polymorphisms and possible gene-gene interactions in metabolic and DNA repair genes: effects on DNA damage. Mutat Res 2006; 593: 22–31. 7. Vodicka P, Kumar R, Stetina R et al. Genetic polymorphisms in DNA repair genes and possible links with DNA repair rates, chromosomal aberrations and singlestrand breaks in DNA. Carcinogenesis 2004; 25: 757–763. 8. Matullo G, Palli D, Peluso M et al. XRCC1, XRCC3, XPD gene polymorphisms, smoking and (32)P-DNA adducts in a sample of healthy subjects. Carcinogenesis 2001; 22: 1437–1445. 9. Sanyal S, Festa F, Sakano S et al. Polymorphisms in DNA repair and metabolic genes in bladder cancer. Carcinogenesis 2004; 25: 729–734. 10. Dhote R, Pellicer-Coeuret M, Thiounn N et al. Risk factors for adult renal cell carcinoma: a systematic review and implications for prevention. BJU Int 2000; 86: 20–27. 11. Hunt JD, van der Hel OL, McMillan GP et al. Renal cell carcinoma in relation to cigarette smoking: meta-analysis of 24 studies. Int J Cancer 2005; 114: 101–108. 12. Neumann AS, Sturgis EM, Wei Q. Nucleotide excision repair as a marker for susceptibility to tobacco-related cancers: a review of molecular epidemiological studies. Mol Carcinog 2005; 42: 65–92. 13. Stern MC, Umbach DM, Lunn RM et al. DNA repair gene XRCC3 codon 241 polymorphism, its interaction with smoking and XRCC1 polymorphisms, and bladder cancer risk. Cancer Epidemiol Biomarkers Prev 2002; 11: 939–943. 14. Sakano S, Kumar R, Larsson P et al. A single-nucleotide polymorphism in the XPG gene, and tumour stage, grade, and clinical course in patients with nonmuscle-invasive neoplasms of the urinary bladder. BJU Int 2006; 97: 847–851. 15. Sakano S, Wada T, Matsumoto H et al. Single nucleotide polymorphisms in DNA repair genes might be prognostic factors in muscle-invasive bladder cancer patients treated with chemoradiotherapy. Br J Cancer 2006; 95: 561–570. 16. Sakano S, Matsumoto H, Yamamoto Y et al. Association between DNA repair gene polymorphisms and p53 alterations in Japanese patients with muscleinvasive bladder cancer. Pathobiology 2006; 73: 295–303. 17. de las Penas R, Sanchez-Ronco M, Alberola V et al. Polymorphisms in DNA repair genes modulate survival in cisplatin/gemcitabine-treated non-small-cell lung cancer patients. Ann Oncol 2006; 17: 668–675. 18. Hirata H, Hinoda Y, Matsuyama H et al. Polymorphisms of DNA repair genes are associated with renal cell carcinoma. Biochem Biophys Res Commun 2006; 342: 1058–1062. 19. Patard JJ, Leray E, Rioux-Leclercq N et al. Prognostic value of histologic subtypes in renal cell carcinoma: a multicenter experience. J Clin Oncol 2005; 23: 2763–2771. 20. Sakano S, Berggren P, Kumar R et al. Clinical course of bladder neoplasms and single nucleotide polymorphisms in the CDKN2A gene. Int J Cancer 2003; 104: 98–103.
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by the number of patients included in this subgroup and its heterogeneity (i.e. number of cigarettes smoked). In the case–control study, weak associations were observed between AC and AC + CC genotypes and C alleles of the XPD gene, and decreased individual risk for RCC. However, the sample size was limited to detect these associations, as the variant alleles of the gene were rare. Thus, we could not consider this result conclusive. No significant associations between genotype or allele frequency and RCC risk were observed for other polymorphisms in the XPC, XPG, XRCC1 or XRCC3 gene. Thus, we have concluded this study to be negative, with respect to RCC susceptibility, which is one of the main endpoints of this study. Complete data on smoking were not available for all our controls. Therefore, we could not analyze the influence of DNA repair gene polymorphisms on individual risk for RCC including the smoking habits. Modulated DNA repair capacity of carcinogens in cigarette smoke by the DNA repair gene polymorphisms may be associated with the development of RCC, like some other types of cancer [12, 13, 27]. Analyses of associations of DNA repair gene polymorphisms, individual risk for RCC and the smoking habits of cases and controls would be of great interest. Our previous study [18] of 112 cases and 180 controls, estimated an OR of 2.83 (95% CI 1.24–6.49) for AA genotypes of the XRCC1 (Arg399Gln, G/A) compared with other genotypes. Although the current study was larger and had sufficient power to replicate this, we found no evidence to support the finding of increased individual risk for RCC based on the polymorphisms. This discrepancy could be due to differences in the populations studied. Alternatively, the earlier finding might be a false-positive result [28]. Wacholder et al. [29] have shown that unless the prior probability of an association is high a large proportion of genetic associations showing marginal statistical significance in studies of low to moderate power will be false-positive results. In conclusion, no significant differences in genotype or allele frequencies of DNA repair genes were observed between RCC cases and control subjects and we have concluded this study to be negative with respect to RCC susceptibility. However, our study provides evidence that some DNA repair gene polymorphisms may influence clinicopathologic characteristics at the time of diagnosis or prognosis of RCC, especially in smokers, and that these effects may be due to altered DNA repair capacity by the polymorphisms. To our knowledge, this is the first report on the associations between DNA repair gene polymorphisms and RCC characteristics and prognosis, including interaction with cigarette smoking. We believe that these findings might help clarify the mechanisms of development and progression of RCC. However, with a limited sample size, especially in subdivided groups, our results allow only preliminary conclusions. Functional and larger studies are needed to confirm the associations between DNA repair gene polymorphisms and clinicopathologic characteristics at the time of diagnosis and prognosis of RCC.
Annals of Oncology
Annals of Oncology
21. Mohrenweiser HW, Carrano AV, Fertitta A et al. Refined mapping of the three DNA repair genes, ERCC1, ERCC2, and XRCC1, on human chromosome 19. Cytogenet Cell Genet 1989; 52: 11–14. 22. Gu J, Zhao H, Dinney CP et al. Nucleotide excision repair gene polymorphisms and recurrence after treatment for superficial bladder cancer. Clin Cancer Res 2005; 11: 1408–1415. 23. Gurubhagavatula S, Liu G, Park S et al. XPD and XRCC1 genetic polymorphisms are prognostic factors in advanced non-small-cell lung cancer patients treated with platinum chemotherapy. J Clin Oncol 2004; 22: 2594–2601. 24. Loktionov A. Common gene polymorphisms, cancer progression and prognosis. Cancer Lett 2004; 208: 1–33. 25. Hunter K. Host genetics influence tumour metastasis. Nat Rev Cancer 2006; 6: 141–146.
original article 26. Kawai Y, Sakano S, Korenaga Y et al. Associations of single nucleotide polymorphisms in the vascular endothelial growth factor gene with the characteristics and prognosis of renal cell carcinomas. Eur Urol 2007 In press. 27. Terry PD, Umbach DM, Taylor JA. APE1 genotype and risk of bladder cancer: evidence for effect modification by smoking. Int J Cancer 2006; 118: 3170–3173. 28. Sak SC, Barrett JH, Paul AB et al. The polyAT, intronic IVS11-6 and Lys939Gln XPC polymorphisms are not associated with transitional cell carcinoma of the bladder. Br J Cancer 2005; 92: 2262–2265. 29. Wacholder S, Chanock S, Garcia-Closas M et al. Assessing the probability that a positive report is false: an approach for molecular epidemiology studies. J Natl Cancer Inst 2004; 96: 434–442.
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doi:10.1093/annonc/mdm337 | 1827
Annals of Oncology 18: 1817–1827, 2007 doi:10.1093/annonc/mdm337 Published online 21 August 2007
The association of DNA repair gene polymorphisms with the development and progression of renal cell carcinoma S. Sakano1, Y. Hinoda2, N. Okayama2, Y. Kawai1, Y. Korenaga1, S. Eguchi1, K. Nagao1, C. Ohmi1 & K. Naito1* 1
Department of Urology; 2Department of Laboratory Medicine, Graduate School of Medicine, Yamaguchi University, Ube, Japan
Received 8 February 2007; revised 14 May 2007; accepted 25 May 2007
introduction The complex system of DNA repair enzymes plays a vital role in protecting the genome from the consequences of exogenous and endogenous mutagenic exposure [1]. There are at least four known pathways of DNA repair: base excision repair (BER), nucleotide excision repair (NER), double-strand break (DSB; including homologous recombination and non-homologous end-joining) repair and mismatch repair, which operate on specific types of damaged DNA with each involving numerous molecules [2]. There are several common polymorphisms in genes encoding DNA repair enzymes and some of these polymorphisms are reported to result in subtle structural alterations of the repair enzyme and modulation of the repair capacity. The wild-type and variant genotypes of xeroderma pigmentosum complementation groups C (XPC), D (XPD) and G (XPG), and X-ray repair cross-complementing groups 1 (XRCC1) and 3 (XRCC3) have been shown to be associated with different levels of DNA repair activity using various assays. In this manner, these polymorphisms may contribute to *Correspondence to: Professor Katsusuke Naito, Department of Urology, Graduate School of Medicine, Yamaguchi University, 1-1-1 Minami-Kogushi, Ube, Yamaguchi 755-8505, Japan. Tel: +81-836-22-2275; Fax: +81-836-22-2276; E-mail: [email protected]
ª 2007 European Society for Medical Oncology
interindividual variability in DNA damage repair in the general population [3–8]. In addition, significant associations between the polymorphisms in DNA repair genes and the individual risks for different types of cancer have been reported [2, 9]. Risk factors for renal cell carcinoma (RCC) include cigarette smoking, obesity, history of kidney stones and infection, hypertension and treatment of hypertension with thiazide diuretics [10, 11]. Some of the DNA damage that may occur as a result of these factors would be repaired by DNA repair enzymes. Cigarette smoking is considered the main risk factor for RCC and cigarette smoke contains many known carcinogens. Some of these carcinogens form bulky adducts on DNA that are repaired by the NER pathway [12]. Cigarette smoke is also a rich source of reactive oxygen species (ROS) [13], which can induce base damage, single-strand breaks (SSBs) and DSBs. ROS-induced base damage and SSBs are repaired via the BER pathway, while DSBs can be repaired by either homologous recombination repair or non-homologous end-joining. It is therefore thought that functional polymorphisms in DNA repair genes may be associated with increased individual risk for RCC, as in lung or bladder cancer [2, 9]. In addition, we previously reported associations between some DNA repair gene polymorphisms and tumor stage, grade, p53 alteration or
original article
carcinoma (RCC), including smoking. DNA repair gene polymorphisms modulate the repair capacity and might influence individual risk and progression of RCC. We examined associations between functional polymorphisms and risk, clinicopathologic characteristics and survival of RCC. Patients and methods: The study groups comprised 215 RCC patients and 215 age- and gender-matched healthy controls. Polymorphisms in xeroderma pigmentosum complementation groups C, D and G and X-ray repair crosscomplementing groups 1 and 3 genes were genotyped. Results: No significant differences in DNA repair genotype were observed between RCC cases and controls. In all patients, however, greater numbers (‡3) of total variant alleles in all DNA repair genes studied were associated with less frequent venous extension (P = 0.0079). In smokers, some genotypes were associated with characteristics of RCC (Ps £ 0.0067) and smokers with greater numbers of total variant alleles had improved overall survival (P = 0.040). Conclusion: These results suggest that DNA repair gene polymorphisms may not influence RCC susceptibility, but that some of them may influence RCC progression, especially in smokers, possibly due to altered DNA repair capacity by these polymorphisms. Key words: disease progression, DNA repair, genetic polymorphism, renal cell carcinoma, smoking, survival
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Background: DNA repair enzymes repair some of the DNA damage associated with risk factors for renal cell
original article
patients and methods patients and control subjects The ethical review committee of the Graduate School of Medicine, Yamaguchi University approved this study. Between October 1992 and November 2004, 215 consecutive patients with histopathologically confirmed RCC based on the Union Internationale Contre le Cancer (UICC) and American Joint Committee for Cancer (AJCC) classification (1997) underwent radical or partial nephrectomy at Yamaguchi University Hospital, Yamaguchi, Japan. The 215 age- and gender-matched healthy volunteers were chosen from the same geographical area as the control subjects. The age of each control was matched to within 62 years of the age of each RCC patient. The mean ages of the patient at initial diagnosis and control groups were 63.7 years (range 29–87) and 64.2 years (range 29–87), respectively. Data on Eastern Cooperative Oncology Group performance status (ECOG PS) were only available for 91 RCC patients (PS 0 in 68, PS 1 in 13, PS 2 in 7 and PS 3 in 3 patients). Therefore, we could not analyze the polymorphisms in the subgroups validated for ECOG PS [19]. History of smoking status was obtained from RCC patients through interviews with doctors or nurses, and reviewed by the researchers. For the controls, only age and gender were recorded as personal data. The characteristics of the RCC patients and control subjects, all of whom were native Japanese, are shown in Table 1. All patients underwent chest X-rays, computed tomography (CT) scans and bone scans, and were staged according to the TNM staging system of the UICC (1997). Positive for venous extension was defined as tumor extending grossly into the renal vein or vena cava. Well, moderately and poorly differentiated tumors were histopathologically graded as G1, G2 and G3, respectively, based on the UICC classification (1997). After their operation, patients were followed up by chest X-rays, CT scans and bone scans every 6 months. The median duration of follow-up was 49 months (range 0–160). Of the 180 patients who achieved a state of no evidence of disease after the operation (excluding 34 patients with distant metastasis at the time of diagnosis and one patient with unknown disease status), 40 (22.2%) had local
1818 | Sakano et al.
recurrence or distant metastasis during the follow-up. Out of a total of 215 patients, 58 suffered death from any cause during the follow-up.
DNA extraction and genotyping Peripheral blood samples were collected from each patient and each control subject, and lymphocyte DNA was extracted using the QIAamp DNA Mini Kit (VWR International, West Chester, PA, USA). Polymorphisms in XPC (Lys939Gln, A/C), XPD (Lys751Gln, A/C), XPG (Asp1104His, G/C), XRCC1 (Arg399Gln, G/A) and XRCC3 (Thr241Met, C/T) genes were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The method, including primer sequences and restriction endonucleases for each polymorphism, has been described previously [9, 15]. Briefly, the DNA fragments were amplified from 10 ng of DNA in 10 ll PCR reactions containing 1.5 mM MgCl2, 0.2 mM each dNTP, 0.3 U AmpliTaq Gold DNA polymerase (Applied Biosystems, Foster City, CA, USA) and 0.3 lM of each primer. The PCR products were digested with the appropriate restriction endonucleases that recognized and cut either wild-type or variant sequences at 37C for at least 3 h. The digested PCR products were electrophoresed on 2% agarose gels and stained with ethidium bromide for visualization under ultraviolet (UV) light. In order to control the restriction digestion of the PCR products, genotyping assays were randomly repeated and results were checked for concordance. About 10% of the amplified fragments were also randomly checked by direct DNA sequencing and comparison of the PCR-RFLP and sequencing results showed 100% concordance in all experiments [20]. Variant alleles were defined as C for XPC, C for XPD, C for XPG, A for XRCC1 and T for XRCC3 according to previous reports [7, 9].
statistical analysis Differences in genotype and allele frequencies of the DNA repair genes between the RCC cases and the control subjects, and associations between the genotypes and the clinicopathologic characteristics at the time of diagnosis of the RCC patients, were assessed for statistical significance using the chi-square test or two-sided Fisher’s exact test; odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. P values < 0.01 were considered to indicate statistical significance in these tests because multiple comparisons were conducted. The combined XPD and XRCC1 genotype was analyzed as a variable. As both XPD and XRCC1 genes are located close to each other at 19q13.2–13.3 [21], analysis of the combined XPD and XRCC1 genotype could be meaningful with regard to a specific haplotype. In addition, because the prognosis of cancer patients is likely to involve multistep, multigenic pathways, it is unlikely that any one single genetic polymorphism would have a dramatic effect on clinical outcome, and it is important to take a pathway-based analysis of multiple polymorphic genes [22]. Thus, we also analyzed the number of total variant alleles in all DNA repair genes studied. Overall survival of the RCC patients was calculated from the day of nephrectomy until the last follow-up or death from any cause; patients who were alive at the last follow-up were censored at that time. The association between each DNA repair genotype and overall survival was estimated by calculating the risk ratios (RRs) with 95% CIs using Cox’s proportional hazard regression models. In addition, overall survival was analyzed by plotting Kaplan–Meier curves and the survival probability distributions were compared using the log-rank test. P values < 0.05 were considered to indicate statistical significance in these tests. Data were processed using JMP software (SAS Institute Inc., Cary, NC, USA).
results genotype and allele frequencies of the DNA repair genes in the RCC cases and the control subjects Genotype frequencies of the XPC, XPD, XPG, XRCC1 and XRCC3 genes in the 215 RCC cases and 215 age- and
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prognosis in patients with bladder cancer [14–16]. These polymorphisms may also influence malignant phenotypes of RCC due to the modulated DNA repair capacity and subsequent alterations of other cancer-related genes. In the present study, we hypothesized that functional DNA repair gene polymorphisms might be related to individual susceptibility to RCC and its progression. Using a case–control study in the Yamaguchi region, Japan, we tested whether polymorphisms in the DNA repair genes XPC (Lys939Gln, A/C), XPD (Lys751Gln, A/C) and XPG (Asp1104His, G/C) (involved in NER), XRCC1 (Arg399Gln, G/A) (involved in BER) and XRCC3 (Thr241Met, C/T) (involved in DSB repair) were associated with individual risk of RCC. These polymorphisms were generally selected according to prior data on functional effect or reports of association with malignancies, to increase the likelihood of positive findings [2, 7, 17], and we have consecutively investigated the effects of these polymorphisms on cancer biology [9, 14–16]. To date, there has been only one report of a case–control study on the association between DNA repair gene polymorphisms and individual risk of RCC, studied in the Shimane region, Japan by our group [18]. In the current study, the number of cases is approximately twice that in the previous study. Finally, we examined possible associations between the polymorphisms and clinicopathologic characteristics and overall survival of RCC patients.
Annals of Oncology
original article
Annals of Oncology
Table 1. Clinicopathologic characteristics of the renal cell carcinoma patients and control subjects
Age (years) Gender Smoking status
Primary tumor
Distant metastasis
Venous extension Stage grouping
Histopathologic grading
Histopathologic subtype
gender-matched control subjects were found to be in Hardy–Weinberg equilibrium. The genotype frequencies in the 118 non-smokers and 86 smokers with RCC were also in Hardy–Weinberg equilibrium. No significant associations were detected between the genotypes and age, gender, smoking status or tumor grade. The genotype and allele frequencies in cases and controls are shown in Table 2. The AC and AC + CC genotypes of the XPD gene were less frequent in cases than in controls (OR 0.42, 95% CI 0.19–0.95, P = 0.032 and OR 0.41, 95% CI 0.19–0.88, P = 0.019; respectively; chi-square test). The C alleles of the XPD gene were also less frequent in cases than in controls (OR 0.41, 95% CI 0.20–0.84, P = 0.012; chi-square test). However, these differences were not considered statistically significant because multiple comparisons were conducted. No significant differences in genotype or allele frequencies between cases and controls
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Controls, n (%)
63.7 6 12.2 29–87 148 (68.8) 67 (31.2) 118 (54.9) 86 (40.0) 15 (7.0) 66 (30.7) 5 (2.3) 11 (5.1) 116 (54.0) 28 (13.0) 69 (32.1) 1 (0.5) 1 (0.5) 196 (91.2) 8 (3.7) 8 (3.7) 3 (1.4) 180 (83.7) 34 (15.8) 1 (0.5) 167 (77.7) 48 (22.3) 108 (50.2) 25 (11.6) 41 (19.1) 41 (19.1) 32 (14.9) 140 (65.1) 35 (16.3) 8 (3.7) 205 (95.3) 3 (1.4) 3 (1.4) 1 (0.5) 3 (1.4)
64.2 6 12.5 29–87 148 (68.8) 67 (31.2)
were observed for other polymorphisms in the XPC, XPG, XRCC1 or XRCC3 genes.
association between DNA repair genotypes and characteristics of RCC in all patients Associations between the DNA repair genotypes and primary tumor stage, distant metastasis at the time of diagnosis, venous extension and stage grouping of RCC in all patients are presented in Table 3. Venous extension was significantly less frequent in patients with greater numbers of total variant alleles in all DNA repair genes studied than in those with smaller ones (‡3 compared with <3, OR 0.41, 95% CI 0.21–0.80, P = 0.0079; chi-square test). There were no significant associations between DNA repair genotypes and primary tumor stage, distant metastasis at the time of diagnosis, stage grouping or histopathologic grading in all patients.
doi:10.1093/annonc/mdm337 | 1819
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Regional lymph nodes
Mean 6 SD Range Men Women Non-smoker Smoker <20 pack-years ‡20 pack-years Unknown pack-years Unknown pT1 pT2 pT3 pT4 pTX N0 N1 N2 NX M0 M1 MX Negative Positive Stage I Stage II Stage III Stage IV G1 G2 G3 GX Clear cell renal carcinoma Papillary renal carcinoma Chromophobe renal carcinoma Collecting duct carcinoma Renal cell carcinoma, unclassified
Cases, n (%)
original article
Annals of Oncology
Table 2. Genotype and allele frequencies of DNA repair genes in renal cell carcinoma cases and controls Genotype/allele
Cases, n (%)
Controls, n (%)
OR (95% CI)
XPC (Lys939Gln, A/C)
AA AC CC AC + CC A allele C allele AA AC CC AC + CC A allele C allele GG GC CC GC + CC G allele C allele GG GA AA GA + AA G allele A allele CC CT TT CT + TT C allele T allele
81 97 37 134 259 171 205 9 1 10 419 11 50 93 72 165 193 237 125 81 9 90 331 99 174 38 3 41 386 44
70 114 31 145 254 176 192 20 3 23 404 26 51 99 65 164 201 229 120 85 10 95 325 105 173 33 5 38 379 43
1.00 0.74 1.03 0.80 1.00 0.95 1.00 0.42 0.31 0.41 1.00 0.41 1.00 0.96 1.13 1.03 1.00 1.08 1.00 0.92 0.86 0.91 1.00 0.93 1.00 1.15 0.60 1.07 1.00 1.01
XPD (Lys751Gln, A/C)
XPG (Asp1104His, G/C)
XRCC1 (Arg399Gln, G/A)
XRCC3 (Thr241Met, C/T)
(37.7) (45.1) (17.2) (62.3) (60.2) (39.8) (95.3) (4.2) (0.5) (4.7) (97.4) (2.6) (23.3) (43.3) (33.5) (76.7) (44.9) (55.1) (58.1) (37.7) (4.2) (41.9) (77.0) (23.0) (80.9) (17.7) (1.4) (19.1) (89.8) (10.2)
(32.6) (53.0) (14.4) (67.4) (59.1) (40.9) (89.3) (9.3) (1.4) (10.7) (94.0) (6.0) (23.7) (46.0) (30.2) (76.3) (46.7) (53.3) (55.8) (39.5) (4.7) (44.2) (75.6) (24.4) (82.0) (15.6) (2.4) (18.0) (89.8) (10.2)
(reference) (0.48–1.12) (0.58–1.83) (0.54–1.19) (reference) (0.73–1.25) (reference) (0.19–0.95) (0.03–3.03) (0.19–0.88) (reference) (0.20–0.84) (reference) (0.59–1.55) (0.68–1.89) (0.66–1.60) (reference) (0.82–1.41) (reference) (0.62–1.36) (0.34–2.20) (0.62–1.33) (reference) (0.68–1.27) (reference) (0.69–1.91) (0.14–2.53) (0.66–1.75) (reference) (0.65–1.57)
P valuea 0.15 0.92 0.27 0.73 0.032 0.36 0.019 0.012 0.86 0.64 0.91 0.58 0.66 0.81 0.63 0.63 0.60 0.72 0.78 0.98
a
Chi-square test or two-sided Fisher’s exact test. OR, odds ratio; CI, confidence interval.
association between DNA repair genotypes and characteristics of RCC in non-smokers Associations between the DNA repair genotypes and characteristics of RCC in non-smokers are presented in Table 4. The DNA repair genotypes were not significantly associated with primary tumor stage, distant metastasis at the time of diagnosis, venous extension, stage grouping or histopathologic grading in non-smokers. association between DNA repair genotypes and characteristics of RCC in smokers Although smoking data for current or former smoking status were not completely available for all smokers, the number of former smokers was relatively small. In addition, the subgroups divided by pack-years of cigarette consumption are likely to have more chances for statistical significance due to the small numbers. The current and former smokers were therefore analyzed as one group irrespective of pack-years. Associations between the DNA repair genotypes and primary tumor stage, distant metastasis at the time of diagnosis, venous extension and stage grouping of RCC in smokers are presented in Table 5.
1820 | Sakano et al.
Combined genotypes with at least one variant allele in XPD or XRCC1 were significantly less frequent in patients with pT2, pT3 or pT4 tumors than in those with pT1 (OR 0.24, 95% CI 0.096–0.62, P = 0.0023; chi-square test). Distant metastasis at the time of diagnosis was significantly less frequent in patients with CC genotypes of the XPG gene than in those with GG + GC (OR 0.091, 95% CI 0.011–0.73, P = 0.0067; two-sided Fisher’s exact test). In addition, both GA + AA genotypes of the XRCC1 and genotypes with at least one variant allele in XPD or XRCC1 were significantly less frequent in patients with stage groupings II, III or IV than in those with stage grouping I (OR 0.24, 95% CI 0.096–0.62, P = 0.0023 and OR 0.18, 95% CI 0.071–0.46, P = 0.00023; respectively; chi-square test). There were no significant associations between DNA repair genotypes and venous extension or histopathologic grading in smokers.
DNA repair genotypes and RCC patients’ survival Cox’s proportional hazard regression analysis for DNA repair genotypes influencing overall survival in RCC patients is presented in Table 6. No significant differences were found
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Gene (polymorphism)
doi:10.1093/annonc/mdm337 | 1821
1.00 (reference) 0.91 (0.46–1.81) 0.79 1.00 (reference) 0.59 (0.34–1.01) 0.055 1.00 (reference) 0.61 (0.36–1.05) 0.076
80 (81.6) 18 (18.4) 61 (62.2) 37 (37.8) 55 (56.1) 43 (43.9)
(reference) (1.11–6.51) 0.024 (reference) (0.54–3.39) 0.52
P valuea
(22.2) 10 (29.4) 1.00 (reference) (77.8) 24 (70.6) 0.69 (0.30–1.55) 0.36 (65.0) 25 (73.5) 1.00 (reference) (35.0) 9 (26.5) 0.67 (0.29–1.52) 0.33
89 (49.4) 18 (52.9) 1.00 (reference) 91 (50.6) 16 (47.1) 0.87 (0.42–1.81) 0.71
82 (45.6) 13 (38.2) 0.74 (0.35–1.57) 0.43
98 (54.4) 21 (61.8) 1.00 (reference)
147 (81.7) 26 (76.5) 1.00 (reference) 33 (18.3) 8 (23.5) 1.37 (0.57–3.30) 0.48
103 (57.2) 22 (64.7) 1.00 (reference) 77 (42.8) 12 (35.3) 0.73 (0.34–1.56) 0.42
40 140 117 63
(38.3) (61.7) (82.6) (17.4)
(21.6) (78.4) (62.9) (37.1)
75 (44.9) 92 (55.1)
78 (46.7)
89 (53.3)
129 (77.3) 38 (22.8)
93 (55.7) 74 (44.3)
36 131 105 62
161 (96.4) 6 (3.6)
64 103 138 29
(35.4) (64.6) (83.3) (16.7)
(29.2) (70.8) (79.2) (20.8)
32 (66.7) 16 (33.3)
18 (37.5)
30 (62.5)
45 (93.8) 3 (6.3)
32 (66.7) 16 (33.3)
14 34 38 10
44 (91.7) 4 (8.3)
17 31 40 8
Venous extension, n (%) Negative Positive (reference) (0.58–2.21) 0.71 (reference) (0.40–2.25) 0.91
P valuea
(reference) (0.32–1.38) 0.27 (reference) (0.21–0.96) 0.035
1.00 (reference) 0.41 (0.21–0.80) 0.0079c
0.69 (0.35–1.32) 0.26
1.00 (reference)
1.00 (reference) 0.23 (0.067–0.77) 0.011
1.00 (reference) 0.63 (0.32–1.23) 0.17
1.00 0.67 1.00 0.45
1.00 (reference) 2.44 (0.66–9.03) 0.24
1.00 1.13 1.00 0.95
OR (95% CI)
b
Chi-square test or two-sided Fisher’s exact test. For those polymorphisms with few homozygous variant alleles, only the combined results of the heterozygous and homozygous variant alleles are shown. c The bold entry indicates statistical sinificance. OR, odds ratio; CI, confidence interval.
a
1.00 (reference) 0.62 (0.36–1.07) 0.084
63 (64.3) 35 (35.7)
(reference) (0.50–1.79) 0.85 (reference) (0.40–1.27) 0.25
(41.1) 7 (20.6) 1.00 (58.9) 27 (79.4) 2.69 (83.9) 27 (79.4) 1.00 (16.1) 7 (20.6) 1.35
OR (95% CI)
174 (96.7) 31 (91.2) 1.00 (reference) 6 (3.3) 3 (8.8) 2.81 (0.67–11.80) 0.16
74 106 151 29
Distant metastasis, n (%) M0 M1
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Volume 18 | No. 11 | November 2007 (23.5) (76.5) (70.4) (29.6)
1.00 0.94 1.00 0.71
(reference) (0.56–1.69) 0.92 (reference) (0.24–1.07) 0.073
23 75 69 29
1.00 0.97 1.00 0.51
P valuea
1.00 (reference) 0.78 (0.21–2.85) 0.76
(37.8) (62.2) (87.8) (12.2)
OR (95% CI)
94 (95.9) 4 (4.1)
37 61 86 12
Primary tumor, n (%) pT1 pT2/pT3/pT4
XPC (Lys939Gln, A/C) AA 43 (37.1) AC + CC 73 (62.9) AA + AC 91 (78.5) CC 25 (21.6) XPD (Lys751Gln, A/C)b AA 110 (94.8) AC + CC 6 (5.2) XPG (Asp1104His, G/C) GG 26 (22.4) GC + CC 90 (77.6) GG + GC 73 (62.9) CC 43 (37.1) XRCC1 (Arg399Gln, G/A)b GG 61 (52.6) GA + AA 55 (47.4) XRCC3 (Thr241Met, C/T)b CC 93 (80.2) CT + TT 23 (19.8) Combined XPD and XRCC1 XPD AA and 57 (49.1) XRCC1 GG Other 59 (50.9) Total variant alleles <3 51 (44.0) ‡3 65 (56.0)
Genotype
Table 3. Associations between DNA repair genotypes and characteristics of renal cell carcinoma in all patients
(37.0) (63.0) (77.8) (22.2)
41 66 94 13
(38.3) (61.7) (87.9) (12.2)
1.00 0.95 1.00 0.48
(reference) (0.55–1.64) (reference) (0.23–1.01)
OR (95% CI)
0.050
0.85
P valuea
(23.2) (76.9) (63.9) (36.1)
25 82 74 33
(23.4) (76.6) (69.2) (30.8)
1.00 0.99 1.00 0.79
(reference) (0.53–1.86) (reference) (0.45–1.39)
48 (44.4) 59 (55.1) 1.00 (reference) 60 (55.6) 48 (44.9) 0.65 (0.38–1.11)
56 (51.9) 40 (37.4) 0.55 (0.32–0.96)
52 (48.2) 67 (62.6) 1.00 (reference)
90 (83.3) 84 (78.5) 1.00 (reference) 18 (16.7) 23 (21.5) 1.37 (0.69–2.72)
56 (51.9) 69 (64.5) 1.00 (reference) 52 (48.2) 38 (35.5) 0.59 (0.34–1.02)
25 83 69 39
0.12
0.033
0.37
0.060
0.41
0.97
103 (95.4)102 (95.3) 1.00 (reference) 5 (4.6) 5 (4.7) 1.01 (0.28–3.59) >0.99
40 68 84 24
Stage grouping, n (%) I II/III/IV
Annals of Oncology
original article
1.00 (reference) 3.58 (0.36–35.4) 0.34 1.00 0.84 1.00 0.81 1.00 (reference) 0.95 (0.45–1.98) 0.89 1.00 (reference) 1.12 (0.51–2.79) 0.68 1.00 (reference) 1.03 (0.50–2.14) 0.93 1.00 (reference) 0.72 (0.35–1.48) 0.37
(94.6) (5.5) (21.8) (78.2) (72.7) (27.3) (60.0) (40.0) (74.6) (25.5) (56.4) (43.6) (52.7) (47.3)
(41.4) (58.6) (81.8) (18.2)
(19.2) (80.8) (70.7) (29.3)
49 (49.5) 50 (50.5)
44 (44.4)
55 (55.6)
77 (77.8) 22 (22.2)
57 (57.6) 42 (42.4)
19 80 70 29
97 (98.0) 2 (2.0)
41 58 81 18
(22.2) (77.8) (77.8) (22.2)
(27.8) (72.2) (66.7) (33.3)
8 (44.4) 10 (55.6)
6 (33.3)
12 (66.7)
12 (66.7) 6 (33.3)
13 (72.2) 5 (27.8)
5 13 12 6
17 (94.4) 1 (5.6)
4 14 14 4
(reference) (0.76–8.06) 0.19 (reference) (0.38–4.37) 0.74
P valuea
(reference) (0.20–1.94) 0.41 (reference) (0.41–3.52) 0.73
1.00 (reference) 1.23 (0.45–3.36) 0.69
0.63 (0.22–1.80) 0.38
1.00 (reference)
1.00 (reference) 1.75 (0.59–5.20) 0.31
1.00 (reference) 0.52 (0.17–1.58) 0.24
1.00 0.62 1.00 1.21
1.00 (reference) 2.85 (0.25–33.2) 0.40
1.00 2.47 1.00 1.29
OR (95% CI)
(39.0) (61.1) (80.0) (20.0)
(17.9) (82.1) (67.4) (32.6)
41 (43.2) 54 (56.8)
41 (43.2)
54 (56.8)
68 (71.6) 27 (28.4)
55 (57.9) 40 (42.1)
17 78 64 31
94 (99.0) 1 (1.1)
37 58 76 19
(34.8) (65.2) (82.6) (17.4)
(30.4) (69.6) (82.6) (17.4)
16 (69.6) 7 (30.4)
10 (43.5)
13 (56.5)
22 (95.7) 1 (4.4)
15 (65.2) 8 (34.8)
7 16 19 4
20 (87.0) 3 (13.0)
8 15 19 4
Venous extension, n (%) Negative Positive
(reference) (0.18–1.40) (reference) (0.14–1.39)
0.52
0.21
0.18
0.023
1.00 (reference) 0.33 (0.13–0.88)
1.01 (0.40–2.54)
1.00 (reference)
0.023
0.98
1.00 (reference) 0.11 (0.015–0.89) 0.014
1.00 (reference) 0.73 (0.28–1.90)
1.00 0.50 1.00 0.44
P valuea
(reference) (0.46–3.10) 0.71 (reference) (0.26–2.77) >0.99
1.00 (reference) 14.1 (1.39–143)
1.00 1.20 1.00 0.84
OR (95% CI)
b
Chi-square test or two-sided Fisher’s exact test. For those polymorphisms with few homozygous variant alleles, only the combined results of the heterozygous and homozygous variant alleles are shown. OR, odds ratio; CI, confidence interval.
(reference) (0.34–2.07) 0.71 (reference) (0.36–1.79) 0.60
1.00 0.86 1.00 0.55
Distant metastasis, n (%) M0 M1
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a
P valuea
(reference) (0.41–1.82) 0.70 (reference) (0.21–1.41) 0.21
OR (95% CI)
(40.0) (60.0) (85.5) (14.6)
Primary tumor, n (%) pT1 pT2/pT3/pT4
XPC (Lys939Gln, A/C) AA 23 (36.5) 22 AC + CC 40 (63.5) 33 AA + AC 48 (76.2) 47 CC 15 (23.8) 8 XPD (Lys751Gln, A/C)b AA 62 (98.4) 52 AC + CC 1 (1.6) 3 XPG (Asp1104His, G/C) GG 12 (19.1) 12 GC + CC 51 (81.0) 43 GG + GC 43 (68.3) 40 CC 20 (31.8) 15 XRCC1 (Arg399Gln, G/A)b GG 37 (58.7) 33 GA + AA 26 (41.3) 22 XRCC3 (Thr241Met, C/T)b CC 49 (77.8) 41 CT + TT 14 (22.2) 14 Combined XPD and XRCC1 XPD AA and 36 (57.1) 31 XRCC1 GG Other 27 (42.9) 24 Total variant alleles <3 28 (44.4) 29 ‡3 35 (55.6) 26
Genotype
Table 4. Associations between DNA repair genotypes and characteristics of renal cell carcinoma in non-smokers
(37.3) 23 (39.0) (62.7) 36 (61.0) (84.8) 50 (87.9) (15.3) 9 (12.2)
(20.3) (79.7) (71.2) (28.8)
12 47 41 18
(20.3) (79.7) (69.5) (30.5)
28 (47.5) 29 (49.2) 31 (52.5) 30 (50.9)
25 (42.4) 26 (44.1)
34 (57.6) 33 (55.9)
48 (81.4) 42 (71.2) 11 (18.6) 17 (28.8)
35 (59.3) 35 (59.3) 24 (40.7) 24 (40.7)
12 47 42 17
58 (98.3) 56 (94.9) 1 (1.7) 3 (5.1)
22 37 45 14
Stage grouping, n (%) I II/III/IV (reference) (0.44–1.96) (reference) (0.23–1.47)
(reference) (0.41–2.45) >0.99 (reference) (0.49–2.39) 0.84
0.62
0.25
0.85
P valuea
1.00 (reference) 0.93 (0.45–1.92)
1.07 (0.52–2.22)
1.00 (reference)
1.00 (reference) 1.77 (0.74–4.19)
0.85
0.85
0.19
1.00 (reference) 1.00 (0.48–2.08) >0.99
1.00 1.00 1.00 1.09
1.00 (reference) 3.11 (0.31–30.8)
1.00 0.93 1.00 0.58
OR (95% CI)
original article Annals of Oncology
Volume 18 | No. 11 | November 2007
Primary tumor, n (%) pT1 pT2/pT3/pT4
doi:10.1093/annonc/mdm337 | 1823
62 (86.1) 10 (13.9)
41 (56.9) 31 (43.1) 36 (50.0) 36 (50.0)
1.00 (reference) 0.51 (0.14–1.86) 0.36
1.00 (reference) 0.24 (0.096–0.62) 0.0023c 1.00 (reference) 0.48 (0.20–1.14) 0.096
(21.4) (78.6) (78.6) (21.4)
(35.7) (64.3) (92.9) (7.1)
10 (71.4) 4 (28.6)
9 (64.3) 5 (35.7)
12 (85.7) 2 (14.3)
9 (64.3) 5 (35.7)
5 9 13 1
13 (92.9) 1 (7.1)
3 11 11 3
(reference) (0.67–10.2) (reference) (0.40–7.14) 0.44
0.23
P valuea
(reference) (0.15–1.75) 0.32 (reference) (0.011–0.73) 0.0067c
1.00 (reference) 0.40 (0.12–1.39)
1.00 (reference) 0.74 (0.22–2.41)
0.16
0.77
1.00 (reference) 1.03 (0.20–5.32) >0.99
1.00 (reference) 0.87 (0.27–2.87) >0.99
1.00 0.51 1.00 0.091
1.00 (reference) 1.31 (0.14–12.7) >0.99
1.00 2.62 1.00 1.69
OR (95% CI)
(38.1) (61.9) (85.7) (14.3)
(22.2) (77.8) (54.0) (46.0)
30 (47.6) 33 (52.4)
33 (52.4) 30 (47.6)
53 (84.1) 10 (15.9)
36 (57.1) 27 (42.9)
14 49 34 29
59 (93.7) 4 (6.4)
24 39 54 9
(39.1) (60.9) (82.6) (17.4)
(30.4) (69.6) (78.3) (21.7)
16 (69.6) 7 (30.4)
17 (73.9) 6 (26.1)
21 (91.3) 2 (8.7)
17 (73.9) 6 (26.1)
7 16 18 5
22 (95.7) 1 (4.4)
9 14 19 4
Venous extension, n (%) Negative Positive (reference) (0.36–2.55) (reference) (0.35–4.58) 0.74
0.93
P valuea
(reference) (0.22–1.90) (reference) (0.11–0.99)
1.00 (reference) 0.40 (0.14–1.10)
1.00 (reference) 0.39 (0.14–1.11)
1.00 (reference) 0.51 (0.10–2.50)
1.00 (reference) 0.47 (0.16–1.35)
1.00 0.65 1.00 0.33
0.071
0.073
0.50
0.16
0.041
0.43
1.00 (reference) 0.67 (0.071–6.33) >0.99
1.00 0.96 1.00 1.26
OR (95% CI)
b
Chi-square test or two-sided Fisher’s exact test. For those polymorphisms with few homozygous variant alleles, only the combined results of the heterozygous and homozygous variant alleles are shown. c The bold entries indicate statistical significance. OR, odds ratio; CI, confidence interval.
44 (61.1) 28 (38.9)
(22.2) (77.8) (54.2) (45.8)
1.00 (reference) 0.32 (0.13–0.80) 0.014
(reference) (0.31–2.34) 0.80 (reference) (0.23–1.33) 0.18
16 56 39 33
(41.7) (58.3) (86.1) (13.9)
1.00 0.86 1.00 0.55
30 42 62 10
Distant metastasis, n (%) M0 M1
68 (94.4) 4 (5.6)
(reference) (0.42–2.44) 0.98 (reference) (0.13–1.57) 0.24
P valuea
1.00 (reference) 0.26 (0.028–2.46) 0.36
1.00 1.01 1.00 0.44
OR (95% CI)
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Volume 18 | No. 11 | November 2007
a
XPC (Lys939Gln, A/C) AA 17 (37.8) 15 (37.5) AC + CC 28 (62.2) 25 (62.5) AA + AC 36 (80.0) 36 (90.0) CC 9 (20.0) 4 (10.0) XPD (Lys751Gln, A/C)b AA 41 (91.1) 39 (97.5) AC + CC 4 (8.9) 1 (2.5) XPG (Asp1104His, G/C) GG 10 (22.2) 10 (25.0) GC + CC 35 (77.8) 30 (75.0) GG + GC 24 (53.3) 27 (67.5) CC 21 (46.7) 13 (32.5) XRCC1 (Arg399Gln, G/A)b GG 22 (48.9) 30 (75.0) GA + AA 23 (51.1) 10 (25.0) XRCC3 (Thr241Met, C/T)b CC 37 (82.2) 36 (74.6) CT + TT 8 (17.8) 4 (25.5) Combined XPD and XRCC1 XPD AA and XRCC1 GG 19 (42.2) 30 (75.0) Other 26 (57.8) 10 (25.0) Total variant alleles <3 20 (44.4) 25 (62.5) ‡3 25 (55.6) 15 (37.5)
Genotype
Table 5. Associations between DNA repair genotypes and characteristics of renal cell carcinoma in smokers
(35.7) 18 (40.9) (64.3) 26 (59.1) (78.6) 40 (90.9) (21.4) 4 (9.1)
(21.4) (78.6) (50.0) (50.0)
12 32 31 13
(27.3) (72.7) (70.5) (29.5)
17 (40.5) 29 (65.9) 25 (59.5) 15 (34.1)
16 (38.1) 34 (77.3) 26 (61.9) 10 (22.7)
36 (85.7) 38 (86.4) 6 (14.3) 6 (13.6)
19 (45.2) 34 (77.3) 23 (54.8) 10 (22.7)
9 33 21 21
38 (90.5) 43 (97.7) 4 (9.5) 1 (2.3)
15 27 33 9
Stage grouping, n (%) I II/III/IV (reference) (0.34–1.92) (reference) (0.10–1.30)
(reference) (0.27–1.96) (reference) (0.17–1.02)
0.0023c
0.053
0.53
0.20
0.14
0.62
P valuea
1.00 (reference) 0.35 (0.15–0.84)
1.00 (reference) 0.18 (0.071–0.46)
0.018
0.00023c
1.00 (reference) 0.95 (0.28–3.21) >0.99
1.00 (reference) 0.24 (0.096–0.62)
1.00 0.73 1.00 0.42
1.00 (reference) 0.22 (0.024–2.06)
1.00 0.80 1.00 0.37
OR (95% CI)
Annals of Oncology
original article
Volume 18 | No. 11 | November 2007
54 4 16 42 40 18 36 22 50 8 33 25 33 25
204 10 49 165 142 72 124 90 173 41 118 96 106 108
(reference) (0.84–1.46) 0.48 (reference) (0.96–1.78) 0.081
P value
(reference) (0.63–1.13) 0.24 (reference) (0.69–1.21) 0.57
1.00 (reference) 0.85 (0.65–1.10) 0.22
1.00 (reference) 0.97 (0.74–1.26) 0.83
1.00 (reference) 0.75 (0.49–1.06) 0.10
1.00 (reference) 0.90 (0.69–1.18) 0.45
1.00 0.84 1.00 0.92
1.00 (reference) 1.70 (0.93–2.68) 0.077
1.00 1.10 1.00 1.33
RR (95% CI)
57 61
67 51
90 28
70 48
24 94 83 35
114 4
45 73 95 23
18 16
19 15
28 6
21 13
10 24 24 10
31 3
11 23 25 9
Nonsmokers Cases, n Deaths, n (reference) (0.81–1.68) 0.44 (reference) (0.93–2.03) 0.11
P value
(reference) (0.52–1.11) 0.14 (reference) (0.68–1.43) 0.98
1.00 (reference) 0.91 (0.65–1.28) 0.60
1.00 (reference) 1.05 (0.74–1.47) 0.78
1.00 (reference) 0.79 (0.49–1.19) 0.28
1.00 (reference) 0.97 (0.68–1.37) 0.86
1.00 0.75 1.00 1.01
1.00 (reference) 2.05 (1.00–3.46) 0.051
1.00 1.15 1.00 1.40
RR (95% CI)
45 40
49 36
73 12
52 33
20 65 51 34
80 5
32 53 72 13
Smokers Cases, n
b
For those polymorphisms with few homozygous variant alleles, only the combined results of the heterozygous and homozygous variant alleles are shown. The bold entry indicates statistical significance. RR, risk ratio; CI, confidence interval.
20 38 14 44
80 134 37 177
All patients Cases, n Deaths, n
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a
XPC (Lys939Gln, A/C) AA AC + CC AA + AC CC XPD (Lys751Gln, A/C)a AA AC + CC XPG (Asp1104His, G/C) GG GC + CC GG + GC CC XRCC1 (Arg399Gln, G/A)a GG GA + AA XRCC3 (Thr241Met, C/T)a CC CT + TT Combined XPD and XRCC1 XPD AA and XRCC1 GG Other Total variant alleles <3 ‡3
Genotype
Table 6. Cox’s proportional hazard regression analysis for DNA repair genotypes influencing overall survival in renal cell carcinoma patients
15 7
13 9
20 2
14 8
6 16 15 7
21 1
9 13 18 4
Deaths, n (reference) (0.63–1.50) (reference) (0.57–1.74)
(reference) (0.60–1.57) (reference) (0.45–1.14)
0.31
0.11
0.17
0.18
0.79
0.63
0.84
0.86
P value
1.00 (reference) 0.62 (0.37–0.98) 0.040b
1.00 (reference) 0.79 (0.48–1.24)
1.00 (reference) 0.58 (0.23–1.12)
1.00 (reference) 0.72 (0.42–1.15)
1.00 0.94 1.00 0.74
1.00 (reference) 1.31 (0.31–2.96)
1.00 0.96 1.00 1.06
RR (95% CI)
original article Annals of Oncology
Annals of Oncology
original article
between DNA repair genotypes and the probability of overall survival in all RCC patients or in non-smokers. In smokers, however, the number of total variant alleles in all DNA repair genes studied was significantly associated with overall survival (RR 0.62, 95% CI 0.37–0.98, P = 0.040), thus patients with three or more variant alleles had improved overall survival. Overall survival was plotted for total variant alleles (‡3 compared with <3) using Kaplan–Meier survival curves (Figure 1). Patients with three or more variant alleles were significantly associated with improved overall survival compared with the remaining groups in smokers (P = 0.042; log-rank test).
discussion
Volume 18 | No. 11 | November 2007
Figure 1. Kaplan–Meier overall survival curves for renal cell carcinoma patients in smokers stratified by the number of total variant alleles in all DNA repair genes studied (‡3 compared with <3). Patients with three or more variant alleles were significantly associated with improved overall survival compared with the remaining groups in smokers (P = 0.042; logrank test).
induce alteration of other cancer-related genes in tumor cells and subsequently result in cancer progression, since the accumulation of multiple genetic changes causes cancer development and progression. We previously showed a significant association between the DNA repair gene polymorphism and p53 alteration in patients with muscleinvasive bladder cancer [16]. The investigation into the associations between DNA repair gene polymorphisms and major genetic alterations in RCC is currently ongoing in our laboratory to test the above-mentioned hypothesis. In all patients, DNA repair genotypes were only associated with venous extension. Interestingly, no significant association was found between DNA repair genotypes and clinicopathologic characteristics of RCC in non-smokers, while the genotypes were associated with primary tumor stage, distant metastasis at the time of diagnosis and stage grouping in smokers. Furthermore, the number of total variant alleles in all DNA repair genes studied was associated with overall survival in smokers. Smoking is considered the main risk factor for RCC [11]. Cigarette smoke contains thousands of known compounds, many of which are mutagenic, carcinogenic or both [12]. Some of these carcinogens induce DNA adducts or other types of damage to DNA that are repaired by the DNA repair enzymes. If left unrepaired, these DNA lesions may lead to gene mutations. Impaired DNA repair and several DNA repair gene polymorphisms in NER, BER and DSB repair pathways have been reported to be associated with increased susceptibility to some smoking-related cancers [12, 13, 27]. In smokers, therefore, decreased DNA repair capacity by the DNA repair genotypes for carcinogens in cigarette smoke may cause accumulation of genetic alteration and subsequently more aggressive cancer. This explanation is compatible with our results on RCC in smokers. However, the analysis performed in the subgroup of smokers, regarding the prognosis value of the polymorphisms, is controversial because the power of the analysis is limited
doi:10.1093/annonc/mdm337 | 1825
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In this study, we found some significant associations between DNA repair genotypes and characteristics of RCC. This result may be due to the modulated DNA repair capacity by the DNA repair gene polymorphisms. Various assays have been developed to quantify DNA repair activity for DNA repair gene polymorphisms, including the Comet assay and the host cell reactivation assay [4, 23]. Despite some inconsistencies in the literature, it seems likely that the wild-type and variant genotypes are associated with different levels of DNA repair activity [3–7]. In general, our patients with the wild-type genotypes of DNA repair genes studied were likely to have more advanced RCCs. The wild-type genotypes conferring suboptimal DNA repair in the tumor could lead to biologically more aggressive RCC. It has been shown that the wild-type genotypes of XPC, XPD, XPG or XRCC1 are associated with decreased DNA repair capacity [3, 5–7]. These results are in accord with our findings that patients with the wild-type genotypes have more advanced RCCs. In addition, we previously reported that the wild-type genotypes of the same DNA repair genes were associated with shorter disease-specific survival in muscle-invasive bladder cancer patients [15]. However, it was unclear whether this association resulted from original nature of the tumor related to the genotypes or from additional effects of chemoradiotherapy. In our present study, DNA repair gene polymorphisms potentially influenced malignant phenotypes of RCC, although they were germline variations not somatic mutations in tumor cells. Loktionov [24] demonstrated that both cancer initiation risk and later neoplastic events (tumor growth, invasion, metastatic spread, response to therapeutic interventions and, finally, survival) are strongly affected by factors that are predetermined by the individual’s genetic background. Hunter [25] also stated that recent evidence implies a significant role of germline polymorphisms in cancer progression. Germline polymorphisms may play an important role in cancer progression because cancer development and progression strongly depend on altered interactions between malignant cells and their normal neighbors. We previously reported that some vascular endothelial growth factor (VEGF) genotypes might have effects on clinicopathologic characteristics at the time of diagnosis or prognosis of RCC, possibly through altered VEGF expression [26]. Furthermore, the modulated DNA repair capacity by the DNA repair gene polymorphisms might
original article
conflict of interest statement None declared.
1826 | Sakano et al.
acknowledgements This study was supported in part by a Grant-in-Aid for Scientific Research (C) (19591853) from the Japan Society for the Promotion of Science.
references 1. Hoeijmakers JH. Genome maintenance mechanisms for preventing cancer. Nature 2001; 411: 366–374. 2. Goode EL, Ulrich CM, Potter JD. Polymorphisms in DNA repair genes and associations with cancer risk. Cancer Epidemiol Biomarkers Prev 2002; 11: 1513–1530. 3. Lunn RM, Helzlsouer KJ, Parshad R et al. XPD polymorphisms: effects on DNA repair proficiency. Carcinogenesis 2000; 21: 551–555. 4. Spitz MR, Wu X, Wang Y et al. Modulation of nucleotide excision repair capacity by XPD polymorphisms in lung cancer patients. Cancer Res 2001; 61: 1354–1357. 5. Cornetta T, Festa F, Testa A, Cozzi R. DNA damage repair and genetic polymorphisms: assessment of individual sensitivity and repair capacity. Int J Radiat Oncol Biol Phys 2006; 66: 537–545. 6. Naccarati A, Soucek P, Stetina R et al. Genetic polymorphisms and possible gene-gene interactions in metabolic and DNA repair genes: effects on DNA damage. Mutat Res 2006; 593: 22–31. 7. Vodicka P, Kumar R, Stetina R et al. Genetic polymorphisms in DNA repair genes and possible links with DNA repair rates, chromosomal aberrations and singlestrand breaks in DNA. Carcinogenesis 2004; 25: 757–763. 8. Matullo G, Palli D, Peluso M et al. XRCC1, XRCC3, XPD gene polymorphisms, smoking and (32)P-DNA adducts in a sample of healthy subjects. Carcinogenesis 2001; 22: 1437–1445. 9. Sanyal S, Festa F, Sakano S et al. Polymorphisms in DNA repair and metabolic genes in bladder cancer. Carcinogenesis 2004; 25: 729–734. 10. Dhote R, Pellicer-Coeuret M, Thiounn N et al. Risk factors for adult renal cell carcinoma: a systematic review and implications for prevention. BJU Int 2000; 86: 20–27. 11. Hunt JD, van der Hel OL, McMillan GP et al. Renal cell carcinoma in relation to cigarette smoking: meta-analysis of 24 studies. Int J Cancer 2005; 114: 101–108. 12. Neumann AS, Sturgis EM, Wei Q. Nucleotide excision repair as a marker for susceptibility to tobacco-related cancers: a review of molecular epidemiological studies. Mol Carcinog 2005; 42: 65–92. 13. Stern MC, Umbach DM, Lunn RM et al. DNA repair gene XRCC3 codon 241 polymorphism, its interaction with smoking and XRCC1 polymorphisms, and bladder cancer risk. Cancer Epidemiol Biomarkers Prev 2002; 11: 939–943. 14. Sakano S, Kumar R, Larsson P et al. A single-nucleotide polymorphism in the XPG gene, and tumour stage, grade, and clinical course in patients with nonmuscle-invasive neoplasms of the urinary bladder. BJU Int 2006; 97: 847–851. 15. Sakano S, Wada T, Matsumoto H et al. Single nucleotide polymorphisms in DNA repair genes might be prognostic factors in muscle-invasive bladder cancer patients treated with chemoradiotherapy. Br J Cancer 2006; 95: 561–570. 16. Sakano S, Matsumoto H, Yamamoto Y et al. Association between DNA repair gene polymorphisms and p53 alterations in Japanese patients with muscleinvasive bladder cancer. Pathobiology 2006; 73: 295–303. 17. de las Penas R, Sanchez-Ronco M, Alberola V et al. Polymorphisms in DNA repair genes modulate survival in cisplatin/gemcitabine-treated non-small-cell lung cancer patients. Ann Oncol 2006; 17: 668–675. 18. Hirata H, Hinoda Y, Matsuyama H et al. Polymorphisms of DNA repair genes are associated with renal cell carcinoma. Biochem Biophys Res Commun 2006; 342: 1058–1062. 19. Patard JJ, Leray E, Rioux-Leclercq N et al. Prognostic value of histologic subtypes in renal cell carcinoma: a multicenter experience. J Clin Oncol 2005; 23: 2763–2771. 20. Sakano S, Berggren P, Kumar R et al. Clinical course of bladder neoplasms and single nucleotide polymorphisms in the CDKN2A gene. Int J Cancer 2003; 104: 98–103.
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by the number of patients included in this subgroup and its heterogeneity (i.e. number of cigarettes smoked). In the case–control study, weak associations were observed between AC and AC + CC genotypes and C alleles of the XPD gene, and decreased individual risk for RCC. However, the sample size was limited to detect these associations, as the variant alleles of the gene were rare. Thus, we could not consider this result conclusive. No significant associations between genotype or allele frequency and RCC risk were observed for other polymorphisms in the XPC, XPG, XRCC1 or XRCC3 gene. Thus, we have concluded this study to be negative, with respect to RCC susceptibility, which is one of the main endpoints of this study. Complete data on smoking were not available for all our controls. Therefore, we could not analyze the influence of DNA repair gene polymorphisms on individual risk for RCC including the smoking habits. Modulated DNA repair capacity of carcinogens in cigarette smoke by the DNA repair gene polymorphisms may be associated with the development of RCC, like some other types of cancer [12, 13, 27]. Analyses of associations of DNA repair gene polymorphisms, individual risk for RCC and the smoking habits of cases and controls would be of great interest. Our previous study [18] of 112 cases and 180 controls, estimated an OR of 2.83 (95% CI 1.24–6.49) for AA genotypes of the XRCC1 (Arg399Gln, G/A) compared with other genotypes. Although the current study was larger and had sufficient power to replicate this, we found no evidence to support the finding of increased individual risk for RCC based on the polymorphisms. This discrepancy could be due to differences in the populations studied. Alternatively, the earlier finding might be a false-positive result [28]. Wacholder et al. [29] have shown that unless the prior probability of an association is high a large proportion of genetic associations showing marginal statistical significance in studies of low to moderate power will be false-positive results. In conclusion, no significant differences in genotype or allele frequencies of DNA repair genes were observed between RCC cases and control subjects and we have concluded this study to be negative with respect to RCC susceptibility. However, our study provides evidence that some DNA repair gene polymorphisms may influence clinicopathologic characteristics at the time of diagnosis or prognosis of RCC, especially in smokers, and that these effects may be due to altered DNA repair capacity by the polymorphisms. To our knowledge, this is the first report on the associations between DNA repair gene polymorphisms and RCC characteristics and prognosis, including interaction with cigarette smoking. We believe that these findings might help clarify the mechanisms of development and progression of RCC. However, with a limited sample size, especially in subdivided groups, our results allow only preliminary conclusions. Functional and larger studies are needed to confirm the associations between DNA repair gene polymorphisms and clinicopathologic characteristics at the time of diagnosis and prognosis of RCC.
Annals of Oncology
Annals of Oncology
21. Mohrenweiser HW, Carrano AV, Fertitta A et al. Refined mapping of the three DNA repair genes, ERCC1, ERCC2, and XRCC1, on human chromosome 19. Cytogenet Cell Genet 1989; 52: 11–14. 22. Gu J, Zhao H, Dinney CP et al. Nucleotide excision repair gene polymorphisms and recurrence after treatment for superficial bladder cancer. Clin Cancer Res 2005; 11: 1408–1415. 23. Gurubhagavatula S, Liu G, Park S et al. XPD and XRCC1 genetic polymorphisms are prognostic factors in advanced non-small-cell lung cancer patients treated with platinum chemotherapy. J Clin Oncol 2004; 22: 2594–2601. 24. Loktionov A. Common gene polymorphisms, cancer progression and prognosis. Cancer Lett 2004; 208: 1–33. 25. Hunter K. Host genetics influence tumour metastasis. Nat Rev Cancer 2006; 6: 141–146.
original article 26. Kawai Y, Sakano S, Korenaga Y et al. Associations of single nucleotide polymorphisms in the vascular endothelial growth factor gene with the characteristics and prognosis of renal cell carcinomas. Eur Urol 2007 In press. 27. Terry PD, Umbach DM, Taylor JA. APE1 genotype and risk of bladder cancer: evidence for effect modification by smoking. Int J Cancer 2006; 118: 3170–3173. 28. Sak SC, Barrett JH, Paul AB et al. The polyAT, intronic IVS11-6 and Lys939Gln XPC polymorphisms are not associated with transitional cell carcinoma of the bladder. Br J Cancer 2005; 92: 2262–2265. 29. Wacholder S, Chanock S, Garcia-Closas M et al. Assessing the probability that a positive report is false: an approach for molecular epidemiology studies. J Natl Cancer Inst 2004; 96: 434–442.
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