- Email: [email protected]
FISH-negative nonsmall-cell lung cancer
letters to the editor
doi: 10.1093/annonc/mdv218 Published online 4 May 2015
An activating ALK gene mutation in ALK IHC-positive/FISHnegative nonsmall-cell lung cancer ALK inhibitors (i.e. crizotinib and alectinib) exhibit marked antitumor activity against nonsmall-cell lung cancer (NSCLC) with ALK rearrangements [1, 2]. The detection of ALK rearrangements is mainly carried out using fluorescence in situ hybridization (FISH). However, such analyses can yield false-positive and falsenegative results [3, 4]. Other ALK diagnostic techniques have been developed, including immunohistochemistry (IHC) for the detection of the ALK protein [5]. Several studies have shown that IHC is sensitive and specific for the determination of ALK protein expression and is an accessible, cost-effective, and rapid alternative to the ALK FISH assay. In addition, some authors have reported significant clinical improvement with crizotinib in patients with tumors that were designated as ALK-negative | letters to the editor
using FISH but were found to be ALK-positive using IHC, raising the possibility that the FISH assay may miss cases that could benefit from ALK inhibitors [4]. Recently, Ilie et al. reported that the discrepancies observed between IHC and FISH data can reflect unexpected biological events, rather than technical issues, which could potentially have a major impact on therapeutic strategies involving ALK inhibitors [3]. In our present study, we discovered an ALK kinase domain mutation (R1192G) in an ALK IHC-positive but FISH-negative NSCLC specimen (Figure 1A). ALK was phosphorylated when this mutation was overexpressed in the HEK293 cell line (Figure 1B). A focus formation assay using the NIH-3T3 cell line showed that the ALK R1192G mutation had transformational abilities, compared with the controls (Figure 1B). The ALK mutationoverexpressed Ba/F3 cell line showed IL-3-independent growth and was sensitive to ALK inhibitors (crizotinib and alectinib) (Figure 1C). The sensitivity of the cell lines to drugs was consistent with the suppression of phospho-ALK (Figure 1C). In vivo, the growth of tumors from the Ba/F3-ALK R1192G cell line was reduced by alectinib treatment in a dose-dependent manner (Figure 1D). These findings indicate that ALK inhibitors are effective against NSCLC cells carrying the ALK R1192G mutation. To the best of our knowledge, this is the first study to show that a clinical sample with ALK IHC-positive/FISH-negative findings has an ALK-activating mutation. Although this patient has not been treated with any ALK inhibitors because of no recurrence, ALK inhibitors can be effective against such NSCLC cells. Indeed, preliminary data showed that ALK IHC-positive/FISH-negative patients responded to crizotinib [4]. In clinical samples, however, no additional ALK mutation was detected in the other 49 surgically resected NSCLC specimens using next-generation sequencing (supplementary Table S1, available at Annals of Oncology online). In conclusion, we identified an ALK-activating mutation in an NSCLC clinical sample with ALK IHC-positive/FISH-negative findings and showed that ALK inhibitors can be effective against NSCLC cells carrying this mutation. Because clinical data are lacking, further clinical testing to validate the use of ALK inhibitors for patients with NSCLC carrying this ALK mutation should be carried out. To ensure that candidates for treatment with ALK inhibitors are not missed, further comprehensive analyses, such as NGS, should be introduced into clinical practice. Y. Togashi1, H. Mizuuchi2, Y. Kobayashi2, H. Hayashi1, M. Terashima1, K. Sakai1, E. Banno1, T. Mizukami1, Y. Nakamura1, M. A. de Velasco1, Y. Fujita1, S. Tomida1, T. Mitsudomi2 & K. Nishio1* Departments of 1Genome Biology; 2 Thoracic Surgery, Kinki University Faculty of Medicine, Osaka, Japan (*E-mail: [email protected])
acknowledgements We thank Y. Hosono for the pathological review.
funding This study was supported by a Grant-in Aid from the Japan Society for the Promotion of Science Fellowship (26-12493).
Volume 26 | No. 8 | August 2015
Downloaded from http://annonc.oxfordjournals.org/ at Main Library of Gazi University on December 28, 2015
6. Pagani O, Regan MM, Walley BA et al. Adjuvant exemestane with ovarian suppression in premenopausal breast cancer. N Engl J Med. 2014; 371: 107–118. 7. Coates AS, Winer EP, Goldhirsch A et al. Tailoring therapies—improving the management of early breast cancer: St Gallen International Expert Consensus on the Primary Therapy of Early Breast Cancer 2015. Ann Oncol 2015; 26: 1533–1546. 8. Early Breast Cancer Trialists’ Collaborative Group (EBCTCG). Effects of chemotherapy and hormonal therapy for early breast cancer on recurrence and 15-year survival: an overview of the randomised trials. Lancet. 2005; 365: 1687–1717. 9. International Breast Cancer Study Group (IBCSG), Castiglione-Gertsch M, O’Neill A et al. Adjuvant chemotherapy followed by goserelin versus either modality alone for premenopausal lymph node-negative breast cancer: a randomized trial. J Natl Cancer Inst 2003; 95: 1833–1846. 10. Jonat W, Kaufmann M, Sauerbrei W et al. Goserelin versus cyclophosphamide, methotrexate, and fluorouracil as adjuvant therapy in premenopausal patients with node-positive breast cancer: The Zoladex Early Breast Cancer Research Association Study. J Clin Oncol 2002; 20: 4628–4635. 11. Jakesz R, Hausmaninger H, Kubista E et al. Randomized adjuvant trial of tamoxifen and goserelin versus cyclophosphamide, methotrexate, and fluorouracil: evidence for the superiority of treatment with endocrine blockade in premenopausal patients with hormone-responsive breast cancer—Austrian Breast and Colorectal Cancer Study Group Trial 5. J Clin Oncol 2002; 20: 4621–4627. 12. Burstein HJ, Temin S, Anderson H et al. Adjuvant endocrine therapy for women with hormone receptor-positive breast cancer: American Society of Clinical Oncology Clinical Practice Guideline focused update. J Clin Oncol 2014; 32: 2255–2269. 13. Colleoni M, Giobbie-Hurder A. Benefits and adverse effects of endocrine therapy. Ann Oncol 2010; 21(Suppl 7): vii107–11. 14. Gnant M, Mlineritsch B, Luschin-Ebengreuth G et al. Adjuvant endocrine therapy plus zoledronic acid in premenopausal women with early-stage breast cancer: 5year follow-up of the ABCSG-12 bone-mineral density substudy. Lancet Oncol 2008; 9: 840–849. 15. Pfeiler G, Königsberg R, Fesl C et al. Impact of body mass index on the efficacy of endocrine therapy in premenopausal patients with breast cancer: an analysis of the prospective ABCSG-12 trial. J Clin Oncol 2011; 29: 2653–2659. 16. Gnant M, Steger GG. Fighting overtreatment in adjuvant breast cancer therapy. Lancet 2009; 374: 2029–2030.
Annals of Oncology
letters to the editor
Annals of Oncology
A
Case 1
Case 2
Case 3
ALK R1192G ALK wild-type (Case 2) (Case 1)
B
pQCLIN-EGFP pQCLIN-ALK wild-type pQCLIN-ALK F1174L pQCLIN-ALK R1192G P-ALK
– – – –
+ – – –
– + – –
– – + –
– – – +
ALK b-actin
100
EGFP
ALK wild-type F1174L
R1192G KRAS G12D
ALK F1174L crizotinib ALK F1174L alectinib
80
ALK R1192G crizotinib
60
D
ALK R1192G alectinib KRA S G12D crizotinib
40 20
KRA S G12D alectinib
0 0.0001
0.001 0.01 0.1 Concentration (mM)
1
ALK F1174L Crizotinib (mM) Alectinib (mM)
ALK R1192G Crizotinib (mM) Alectinib (mM)
03 1 3 03 1 3 0 0.0 0.0 0.0 0 0.0 0.0 0.0
03 1 3 03 1 3 0 0.0 0.0 0.0 0 0.0 0.0 0.0
P-ALK ALK b-actin
1800.00
Alectinib
1600.00 Tumor volume (mm3)
120
GCCCCGGT
1400.00
Vehicle
1200.00
*
1000.00
*
800.00
*
600.00 400.00
Alectinib (20 mg/kg) Alectinib (60 mg/kg)
200.00 0.00 1
4
8
11
(Days)
Figure 1. (A) Immunohistochemistry (IHC), fluorescence in situ hybridization (FISH), and direct sequencing for ALK in clinical samples. Case 1 (63-year-old man, past smoker) was focally positive, case 2 (65-year-old man, past smoker) was negative, and case 3 (68-year-old woman, never smoker) was positive for ALK IHC. The ALK FISH split assay showed merged signals in cases 1 and 2, suggesting no rearrangement of ALK, but showed split 50 -side (green) and 30 -side (red) signals in case 3, suggesting an ALK rearrangement. ALK exon 23 sequencing revealed an ALK R1192G mutation (C > G) in case 1. We used case 2 as a wild-type control. Scale bars, 20 µm. (B) Phosphorylation of ALK in the transfectant HEK293 cell lines and transformational ability of each ALK mutation. The expressions of ALK in the transfectant cell lines were confirmed using western blot analyses. ALK was phosphorylated in the HEK293-ALK F1174L ( positive control) and HEK293-ALK R1192G cell lines, compared with the HEK293, HEK293-EGFP, and HEK293-ALK wild-type cell lines. β-Actin was used as an internal control. Based on a focus formation assay and the NIH-3T3 cell lines, both ALK mutations exhibited transformational abilities. A cell line overexpressing the KRAS G12D mutation was used as a positive control. Scale bars, 50 µm. (C) Sensitivities of the transfectant Ba/F3 cell lines to ALK inhibitors and phosphorylation level of ALK after exposure to ALK inhibitors. Both ALK inhibitors (crizotinib and alectinib) were effective against each mutant-driven cell lines, while the Ba/F3-KRAS G12D cell line was not sensitive to the inhibitors. The respective 50% inhibitory concentrations (IC50) of each Ba/F3 cell line to crizotinib and alectinib were 0.039 and 0.0062 µM for F1174L and 0.042 and 0.0078 µM for R1192G. In contrast, the IC50 values of the Ba/F3-KRAS G12D cell line to crizotinib and alectinib were rather high (0.87 and 1.38 µM, respectively). The phosphorylation levels were measured in samples collected 3 h after exposure to the ALK inhibitors (0, 0.003, 0.01, and 0.03 µM) using western blot analyses. Both inhibitors induced a significant decrease in the phosphorylation levels of ALK in the transfectant cell lines. β-Actin was used as an internal control. Line, mean of independent triplicate experiments. (D) Xenograft study. We used the Ba/F3-ALK R1192G cell line in the xenograft study. In the treatment groups, alectinib (20 or 60 mg/kg) was administered by oral gavage daily for 10 days; the control animals received 0.5% methylcellulose as the vehicle. Tumor growth from the Ba/F3-ALK R1192G cell line was reduced by treatment with alectinib in a dose-dependent manner [vehicle: 1345.49 ± 269.84 mm3 versus alectinib (20 mg/kg): 838.1 ± 127.43 mm3, P = 0.0052* or versus alectinib (60 mg/kg): 550.0 ± 158.6 mm3, P = 0.00046*; alectinib (20 mg/kg) versus alectinib (60 mg/kg), P = 0.013*]. Lines, mean of values for five mice; error bars, SD; *P < 0.05.
disclosure TM received honoraria from Pfizer and Chugai Pharmaceuticals. KN received honoraria from Chugai Pharmaceuticals. All remaining authors have declared no conflicts of interest.
references 1. Kwak EL, Bang YJ, Camidge DR et al. Anaplastic lymphoma kinase inhibition in non-small-cell lung cancer. N Engl J Med 2010; 363: 1693–1703. 2. Seto T, Kiura K, Nishio M et al. CH5424802 (RO5424802) for patients with ALK-rearranged advanced non-small-cell lung cancer (AF-001JP study): a single-arm, open-label, phase 1–2 study. Lancet Oncol 2013; 14: 590–598.
Volume 26 | No. 8 | August 2015
3. Ilie MI, Bence C, Hofman V et al. Discrepancies between FISH and immunohistochemistry for assessment of the ALK status are associated with ALK ‘borderline’-positive rearrangements or a high copy number: a potential major issue for anti-ALK therapeutic strategies. Ann Oncol 2015; 26: 238–244. 4. Cabillic F, Gros A, Dugay F et al. Parallel FISH and immunohistochemical studies of ALK status in 3244 non-small-cell lung cancers reveal major discordances. J Thorac Oncol 2014; 9: 295–306. 5. Takeuchi K, Choi YL, Togashi Y et al. KIF5B-ALK, a novel fusion oncokinase identified by an immunohistochemistry-based diagnostic system for ALK-positive lung cancer. Clin Cancer Res 2009; 15: 3143–3149.
doi: 10.1093/annonc/mdv240 Published online 22 May 2015
doi:10.1093/annonc/mdv240 |
Downloaded from http://annonc.oxfordjournals.org/ at Main Library of Gazi University on December 28, 2015
C Proliferation (%)
GCCCGGGT C
doi: 10.1093/annonc/mdv218 Published online 4 May 2015
An activating ALK gene mutation in ALK IHC-positive/FISHnegative nonsmall-cell lung cancer ALK inhibitors (i.e. crizotinib and alectinib) exhibit marked antitumor activity against nonsmall-cell lung cancer (NSCLC) with ALK rearrangements [1, 2]. The detection of ALK rearrangements is mainly carried out using fluorescence in situ hybridization (FISH). However, such analyses can yield false-positive and falsenegative results [3, 4]. Other ALK diagnostic techniques have been developed, including immunohistochemistry (IHC) for the detection of the ALK protein [5]. Several studies have shown that IHC is sensitive and specific for the determination of ALK protein expression and is an accessible, cost-effective, and rapid alternative to the ALK FISH assay. In addition, some authors have reported significant clinical improvement with crizotinib in patients with tumors that were designated as ALK-negative | letters to the editor
using FISH but were found to be ALK-positive using IHC, raising the possibility that the FISH assay may miss cases that could benefit from ALK inhibitors [4]. Recently, Ilie et al. reported that the discrepancies observed between IHC and FISH data can reflect unexpected biological events, rather than technical issues, which could potentially have a major impact on therapeutic strategies involving ALK inhibitors [3]. In our present study, we discovered an ALK kinase domain mutation (R1192G) in an ALK IHC-positive but FISH-negative NSCLC specimen (Figure 1A). ALK was phosphorylated when this mutation was overexpressed in the HEK293 cell line (Figure 1B). A focus formation assay using the NIH-3T3 cell line showed that the ALK R1192G mutation had transformational abilities, compared with the controls (Figure 1B). The ALK mutationoverexpressed Ba/F3 cell line showed IL-3-independent growth and was sensitive to ALK inhibitors (crizotinib and alectinib) (Figure 1C). The sensitivity of the cell lines to drugs was consistent with the suppression of phospho-ALK (Figure 1C). In vivo, the growth of tumors from the Ba/F3-ALK R1192G cell line was reduced by alectinib treatment in a dose-dependent manner (Figure 1D). These findings indicate that ALK inhibitors are effective against NSCLC cells carrying the ALK R1192G mutation. To the best of our knowledge, this is the first study to show that a clinical sample with ALK IHC-positive/FISH-negative findings has an ALK-activating mutation. Although this patient has not been treated with any ALK inhibitors because of no recurrence, ALK inhibitors can be effective against such NSCLC cells. Indeed, preliminary data showed that ALK IHC-positive/FISH-negative patients responded to crizotinib [4]. In clinical samples, however, no additional ALK mutation was detected in the other 49 surgically resected NSCLC specimens using next-generation sequencing (supplementary Table S1, available at Annals of Oncology online). In conclusion, we identified an ALK-activating mutation in an NSCLC clinical sample with ALK IHC-positive/FISH-negative findings and showed that ALK inhibitors can be effective against NSCLC cells carrying this mutation. Because clinical data are lacking, further clinical testing to validate the use of ALK inhibitors for patients with NSCLC carrying this ALK mutation should be carried out. To ensure that candidates for treatment with ALK inhibitors are not missed, further comprehensive analyses, such as NGS, should be introduced into clinical practice. Y. Togashi1, H. Mizuuchi2, Y. Kobayashi2, H. Hayashi1, M. Terashima1, K. Sakai1, E. Banno1, T. Mizukami1, Y. Nakamura1, M. A. de Velasco1, Y. Fujita1, S. Tomida1, T. Mitsudomi2 & K. Nishio1* Departments of 1Genome Biology; 2 Thoracic Surgery, Kinki University Faculty of Medicine, Osaka, Japan (*E-mail: [email protected])
acknowledgements We thank Y. Hosono for the pathological review.
funding This study was supported by a Grant-in Aid from the Japan Society for the Promotion of Science Fellowship (26-12493).
Volume 26 | No. 8 | August 2015
Downloaded from http://annonc.oxfordjournals.org/ at Main Library of Gazi University on December 28, 2015
6. Pagani O, Regan MM, Walley BA et al. Adjuvant exemestane with ovarian suppression in premenopausal breast cancer. N Engl J Med. 2014; 371: 107–118. 7. Coates AS, Winer EP, Goldhirsch A et al. Tailoring therapies—improving the management of early breast cancer: St Gallen International Expert Consensus on the Primary Therapy of Early Breast Cancer 2015. Ann Oncol 2015; 26: 1533–1546. 8. Early Breast Cancer Trialists’ Collaborative Group (EBCTCG). Effects of chemotherapy and hormonal therapy for early breast cancer on recurrence and 15-year survival: an overview of the randomised trials. Lancet. 2005; 365: 1687–1717. 9. International Breast Cancer Study Group (IBCSG), Castiglione-Gertsch M, O’Neill A et al. Adjuvant chemotherapy followed by goserelin versus either modality alone for premenopausal lymph node-negative breast cancer: a randomized trial. J Natl Cancer Inst 2003; 95: 1833–1846. 10. Jonat W, Kaufmann M, Sauerbrei W et al. Goserelin versus cyclophosphamide, methotrexate, and fluorouracil as adjuvant therapy in premenopausal patients with node-positive breast cancer: The Zoladex Early Breast Cancer Research Association Study. J Clin Oncol 2002; 20: 4628–4635. 11. Jakesz R, Hausmaninger H, Kubista E et al. Randomized adjuvant trial of tamoxifen and goserelin versus cyclophosphamide, methotrexate, and fluorouracil: evidence for the superiority of treatment with endocrine blockade in premenopausal patients with hormone-responsive breast cancer—Austrian Breast and Colorectal Cancer Study Group Trial 5. J Clin Oncol 2002; 20: 4621–4627. 12. Burstein HJ, Temin S, Anderson H et al. Adjuvant endocrine therapy for women with hormone receptor-positive breast cancer: American Society of Clinical Oncology Clinical Practice Guideline focused update. J Clin Oncol 2014; 32: 2255–2269. 13. Colleoni M, Giobbie-Hurder A. Benefits and adverse effects of endocrine therapy. Ann Oncol 2010; 21(Suppl 7): vii107–11. 14. Gnant M, Mlineritsch B, Luschin-Ebengreuth G et al. Adjuvant endocrine therapy plus zoledronic acid in premenopausal women with early-stage breast cancer: 5year follow-up of the ABCSG-12 bone-mineral density substudy. Lancet Oncol 2008; 9: 840–849. 15. Pfeiler G, Königsberg R, Fesl C et al. Impact of body mass index on the efficacy of endocrine therapy in premenopausal patients with breast cancer: an analysis of the prospective ABCSG-12 trial. J Clin Oncol 2011; 29: 2653–2659. 16. Gnant M, Steger GG. Fighting overtreatment in adjuvant breast cancer therapy. Lancet 2009; 374: 2029–2030.
Annals of Oncology
letters to the editor
Annals of Oncology
A
Case 1
Case 2
Case 3
ALK R1192G ALK wild-type (Case 2) (Case 1)
B
pQCLIN-EGFP pQCLIN-ALK wild-type pQCLIN-ALK F1174L pQCLIN-ALK R1192G P-ALK
– – – –
+ – – –
– + – –
– – + –
– – – +
ALK b-actin
100
EGFP
ALK wild-type F1174L
R1192G KRAS G12D
ALK F1174L crizotinib ALK F1174L alectinib
80
ALK R1192G crizotinib
60
D
ALK R1192G alectinib KRA S G12D crizotinib
40 20
KRA S G12D alectinib
0 0.0001
0.001 0.01 0.1 Concentration (mM)
1
ALK F1174L Crizotinib (mM) Alectinib (mM)
ALK R1192G Crizotinib (mM) Alectinib (mM)
03 1 3 03 1 3 0 0.0 0.0 0.0 0 0.0 0.0 0.0
03 1 3 03 1 3 0 0.0 0.0 0.0 0 0.0 0.0 0.0
P-ALK ALK b-actin
1800.00
Alectinib
1600.00 Tumor volume (mm3)
120
GCCCCGGT
1400.00
Vehicle
1200.00
*
1000.00
*
800.00
*
600.00 400.00
Alectinib (20 mg/kg) Alectinib (60 mg/kg)
200.00 0.00 1
4
8
11
(Days)
Figure 1. (A) Immunohistochemistry (IHC), fluorescence in situ hybridization (FISH), and direct sequencing for ALK in clinical samples. Case 1 (63-year-old man, past smoker) was focally positive, case 2 (65-year-old man, past smoker) was negative, and case 3 (68-year-old woman, never smoker) was positive for ALK IHC. The ALK FISH split assay showed merged signals in cases 1 and 2, suggesting no rearrangement of ALK, but showed split 50 -side (green) and 30 -side (red) signals in case 3, suggesting an ALK rearrangement. ALK exon 23 sequencing revealed an ALK R1192G mutation (C > G) in case 1. We used case 2 as a wild-type control. Scale bars, 20 µm. (B) Phosphorylation of ALK in the transfectant HEK293 cell lines and transformational ability of each ALK mutation. The expressions of ALK in the transfectant cell lines were confirmed using western blot analyses. ALK was phosphorylated in the HEK293-ALK F1174L ( positive control) and HEK293-ALK R1192G cell lines, compared with the HEK293, HEK293-EGFP, and HEK293-ALK wild-type cell lines. β-Actin was used as an internal control. Based on a focus formation assay and the NIH-3T3 cell lines, both ALK mutations exhibited transformational abilities. A cell line overexpressing the KRAS G12D mutation was used as a positive control. Scale bars, 50 µm. (C) Sensitivities of the transfectant Ba/F3 cell lines to ALK inhibitors and phosphorylation level of ALK after exposure to ALK inhibitors. Both ALK inhibitors (crizotinib and alectinib) were effective against each mutant-driven cell lines, while the Ba/F3-KRAS G12D cell line was not sensitive to the inhibitors. The respective 50% inhibitory concentrations (IC50) of each Ba/F3 cell line to crizotinib and alectinib were 0.039 and 0.0062 µM for F1174L and 0.042 and 0.0078 µM for R1192G. In contrast, the IC50 values of the Ba/F3-KRAS G12D cell line to crizotinib and alectinib were rather high (0.87 and 1.38 µM, respectively). The phosphorylation levels were measured in samples collected 3 h after exposure to the ALK inhibitors (0, 0.003, 0.01, and 0.03 µM) using western blot analyses. Both inhibitors induced a significant decrease in the phosphorylation levels of ALK in the transfectant cell lines. β-Actin was used as an internal control. Line, mean of independent triplicate experiments. (D) Xenograft study. We used the Ba/F3-ALK R1192G cell line in the xenograft study. In the treatment groups, alectinib (20 or 60 mg/kg) was administered by oral gavage daily for 10 days; the control animals received 0.5% methylcellulose as the vehicle. Tumor growth from the Ba/F3-ALK R1192G cell line was reduced by treatment with alectinib in a dose-dependent manner [vehicle: 1345.49 ± 269.84 mm3 versus alectinib (20 mg/kg): 838.1 ± 127.43 mm3, P = 0.0052* or versus alectinib (60 mg/kg): 550.0 ± 158.6 mm3, P = 0.00046*; alectinib (20 mg/kg) versus alectinib (60 mg/kg), P = 0.013*]. Lines, mean of values for five mice; error bars, SD; *P < 0.05.
disclosure TM received honoraria from Pfizer and Chugai Pharmaceuticals. KN received honoraria from Chugai Pharmaceuticals. All remaining authors have declared no conflicts of interest.
references 1. Kwak EL, Bang YJ, Camidge DR et al. Anaplastic lymphoma kinase inhibition in non-small-cell lung cancer. N Engl J Med 2010; 363: 1693–1703. 2. Seto T, Kiura K, Nishio M et al. CH5424802 (RO5424802) for patients with ALK-rearranged advanced non-small-cell lung cancer (AF-001JP study): a single-arm, open-label, phase 1–2 study. Lancet Oncol 2013; 14: 590–598.
Volume 26 | No. 8 | August 2015
3. Ilie MI, Bence C, Hofman V et al. Discrepancies between FISH and immunohistochemistry for assessment of the ALK status are associated with ALK ‘borderline’-positive rearrangements or a high copy number: a potential major issue for anti-ALK therapeutic strategies. Ann Oncol 2015; 26: 238–244. 4. Cabillic F, Gros A, Dugay F et al. Parallel FISH and immunohistochemical studies of ALK status in 3244 non-small-cell lung cancers reveal major discordances. J Thorac Oncol 2014; 9: 295–306. 5. Takeuchi K, Choi YL, Togashi Y et al. KIF5B-ALK, a novel fusion oncokinase identified by an immunohistochemistry-based diagnostic system for ALK-positive lung cancer. Clin Cancer Res 2009; 15: 3143–3149.
doi: 10.1093/annonc/mdv240 Published online 22 May 2015
doi:10.1093/annonc/mdv240 |
Downloaded from http://annonc.oxfordjournals.org/ at Main Library of Gazi University on December 28, 2015
C Proliferation (%)
GCCCGGGT C