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INTENSITY-MODULATED RADIOTHERAPY (IMRT) FOR PROSTATE CANCER AT GHENT UNIVERSITY HOSPITAL (GUH): FIRST REPORT ON LATE TOXICITY
581
582
GREEN TEA (EGCG) AND PROSTATE CANCER: A NEW SPHINGOSINE KINASE INHIBITOR?
MODIFICATION OF PROLIFERATION, APOPTOSIS AND ANDROGEN RECEPTOR EXPRESSION OF LNCAP CELLS BY DIET POLYPHENOLS
Doumerc N.1, Bonhoure E.2, Dayon A.2, Rischmann P.1, Malavaud B.1, Cuvillier O.2
Ferruelo A.1, Angulo J.2, Pascual-mateo C.2, Romero I.2, Lujan M.2, Berenguer A.2 1
1
Hopital Rangueil, Urology, Toulouse, France, 2Hopital Rangueil, Inserm, Toulouse, France INTRODUCTION & OBJECTIVES: The weak incidence of prostate cancer in Asian countries made it possible for the epidemiologists to propose the green tea, and more specifically its active compound the EGCG, as a protective agent against this disease. Here we show our preliminary results obtained in vitro and in vivo concerning the antineoplastic properties of EGCG and its potential link to the sphingosine kinase (SK), an oncogenic lipid kinase overexpressed in many solid tumours. MATERIAL & METHODS: In vitro: cell viability of 2 cell human prostate cancer cell lines PC3 and PC3/SK (overexpressing SK) was studied using MTT assay. Enzymatic activity of SK in response to the EGCG was assayed. In vivo: orthotopical xenografts of PC3/GFP cells (overexpressing green fluorescent protein GFP) were established in the Nude mice. EGCG was administrated orally 3 weeks before and 3 weeks after the xenograft. Mice were sacrificed and assayed for fluorescence using digital stereomicroscopy. RESULTS: In vitro, EGCG triggers apoptosis in both LNCaP and PC-3 cell lines. This effect is correlated with SK inhibition. Demonstrating the importance of SK in the cytotoxic effect of EGCG, overexpression of SK could prevent cell death triggered by EGCG. In vivo, we fount that EGCG treatment of Nude mice orthotopically transplanted by PC-3 / GFP cells led to strong decrease in primary tumour volume as well as in the occurrence of metastases. Importantly, this effect was correlated with inhibition of SK in primary tumour samples. CONCLUSIONS: The EGCG, the principal component of the green tea, induces apoptosis in prostate cancer cells, and SK seems to be involved in its effect. P36 PROSTATE CANCER: RADIOTHERAPY AND BRACHYTHERAPY Thursday, 6 April, 14.00-15.30, Room Concorde 3 / Level 4 583 EXTERNAL BEAM RADIOTHERAPY OUTCOMES IN SEPTA- AND OCTOGENARIANS Lebeau T., Perrotte P., Bahary J.P., Saad F., Karakiewicz P.I. University of Montreal, Cancer Prognostics and Outcomes Research Unit, Montreal, Canada INTRODUCTION & OBJECTIVES: An average 70 year old male has a 12 year life expectancy (LE), a 75 year old has a 9 year LE, an 80 year old has a 7 year LE, and an 85 year old has a LE of 5 years. Based on life expectancy and comorbidity, definitive treatment of localised prostate cancer in septa- and octogenarians is controversial. We examined crude survival after definitive radiotherapy for clinically localised prostate cancer in the Province of Quebec. MATERIAL & METHODS: The RAMQ database allowed us to identify 3907 patients who were treated with definitive radiotherapy between 1989 and 2000. None received neoadjuvant hormonal therapy. None received hormonal therapy within 12 months of XRT initiation. of these, 2211 (56.6%) were 70 years of age or older and constitute the focus of this analysis. Failures corresponded to initiation of hormonal therapy. RESULTS: Of 2211 patients, 1169 (52.9) were aged 70-74 years, 741 (33.5%) were aged 75-79 years, 231 (10.4%) were aged 80-84 years and 70 (3.2%) were 85 or older. Within the 70-74 age category 61.2% died and 19.5% failed. Within the 75-79 age category 74.0% died and 17.5% failed. Within the 80-84 age category, 83.1% died and 11.3% failed. Finally, in the 85+ age category, 88.6% died and 7.1% failed.
Hospital De Getafe, Investigation-Urology, Getafe, Spain, 2Hospital Getafe, Urology, Getafe, Spain INTRODUCTION & OBJECTIVES: Epidemiological and experimental data support the role of polyphenols, compounds abundant in Mediterranean diet, for chemoprofilaxis of prostate cancer. We have evaluated the effect of different polyphenols on cell proliferation, apoptosis and androgen receptor (AR) expression in human prostate cancer LNCaP cells. MATERIAL & METHODS: LNCaP cells (5 x 102) were cultured in microtiter plate modules supplemented by5% charcoal-stripped FCS (c FCS, LINUS, Cultek) and the cells were treated with several concentrations of the following polyphenols:gallic acid, tannic acid and quercetin (1, 5 and 10 μM), rutin and morin (25, 50 and 75 μM) and resveratrol (5, 10 and 25μM). Nontreated LNCaP cells in a carrier solvent (0,1% DMSO or ethanol) were used as control. Colorimetric immunoassay method (Cell Proliferation ELISA BrdU, Roche) assessed the extent of cell proliferation at 24, 48, 72 and 96 hours. Aluminescent assay that measures caspase-3 and -7 activity (Caspase-Glo 3/7 Assay. Promega, Madison, WI, USA) was used to disclose apoptosis at 24, 48 and 72 hours. Relative quantification real-time PCR of AR mARN was achieved by real-time PCR. RESULTS: All polyphenols analysed (gallic acid, tannic acid, quercetin, rutin, morin and resveratrol) significantly inhibited LNCaP cell proliferation with respects to control (p<0.05), with moderate differences between them. Resveratrol was the strongest inhibitor at different times and doses. The weakest and latest (96 h) effect was produced by quercetin. Caspase-3 and -7 activity was also significantly higher compared to control (p<0.05) in the presence of all these polyphenols. Resveratrol increased caspase activity at 24 h and the rest at 48 h, but reached its peak with all of them at 72 h. Resveratrol, quercetin and morin -but not gallic acid, tannic acid or rutin- significantly inhibited AR mRNA expression at the same concentrations that induced caspase activity. Again, resveratrol produced the highest inhibition (88 to 275 times less than control), followed by morin and quercetin (70 to 105 and 57 to 90 times, respectively). CONCLUSIONS: The polyphenols analysed display antiproliferative effect and promote apoptosis when added to cultured LNCaP cells. Among them, resveratrol is the most potent. This and other compounds inhibit the expression of AR mRNA and that could explain, at least in part, their antiproliferative effect. The synergistic effect of these compounds and their potential to prevent progression of hormone-dependent prostate cancer merit further study.
584 INTENSITY-MODULATED RADIOTHERAPY (IMRT) FOR PROSTATE CANCER AT GHENT UNIVERSITY HOSPITAL (GUH): FIRST REPORT ON LATE TOXICITY Fonteyne V.1, Vakaet L.1, Villeirs G.2, Oosterlinck W.3, Denoyette L.1, De Neve W.1, De Meerleer G.1 1 Ghent University Hospital, Radiotherapy, Ghent, Belgium, 2Ghent University Hospital, Radiology, Ghent, Belgium, 3Ghent University Hospital, Urology, Ghent, Belgium
INTRODUCTION & OBJECTIVES: Although dose escalation to the prostate improves local control, higher doses induce an elevated risk of late gastro-intestinal (GI) and genitourinary (GU) complications. IMRT is used to decrease the dose to the prostate-surrounding normal tissues (bladder, rectum, sigmoid, small intestine), while increasing the dose to the prostate (1). This is the first report evaluating late toxicity of our IMRT technology for prostate cancer. MATERIAL & METHODS: This study includes 133 patients treated with IMRT as primary therapy for prostate cancer at GUH between December 1998 and June 2005. Median dose to the prostate (+/- seminal vesicles) was 77 Gy. GI and GU late toxicity was scored using the RTOG criteria (2), supplemented by an in-house developed toxicity scale to score GI urgency and incontinence (3). Patients were seen every 3 months for the first year, every 6 months until year 5 and annually thereafter. RESULTS: Median duration of follow-up was 36 months. Two patients had follow-up less than 3 months and were excluded from this analysis. No patient developed grade 4 toxicity. We observed grade 3 GU toxicity in 4 patients (nocturia) for a median period of 3 months. One patient experienced grade 3 red blood losses per anum (RBPA). Respectively, 19% and 17% of all patients developed grade 2 GU and GI toxicity (grade 2: possible need for oral medication). Most frequent grade 2 late GU toxicities were nocturia (20%), hematuria (18%), and GUfrequency (9%). Most frequent grade 2 late GI toxicities were RBPA (18%), abdominal cramps (6%), GI-continence (5%) and diarrhoea (5%). Except for hematuria, grade 2 side effects disappeared after a median time of 6 months. Hematuria disappeared always after increased water uptake. CONCLUSIONS: IMRT for prostate cancer causes modest levels of treatment-induced late toxicity. In half of the patients, grade 2 & 3 toxicity disappeared after 6 months.
CONCLUSIONS: A large proportion of septa- and octogenarians treated with definitive XRT do not seem to have sufficient LE to warrant such treatment. Our results suggest that the indications for definitive XRT may require a reappraisal.
Eur Urol Suppl 2006;5(2):168
References 1. De Meerleer et al. Int J Radiat Oncol Biol Phys. 2000; 47: 639-648 2. Cox et al. Int J Radiat Oncol Biol Phys. 2001; 51: 849-859. 3. De Meerleer et al. Int J Radiat Oncol Biol Phys. 2004; 60: 777-787.
582
GREEN TEA (EGCG) AND PROSTATE CANCER: A NEW SPHINGOSINE KINASE INHIBITOR?
MODIFICATION OF PROLIFERATION, APOPTOSIS AND ANDROGEN RECEPTOR EXPRESSION OF LNCAP CELLS BY DIET POLYPHENOLS
Doumerc N.1, Bonhoure E.2, Dayon A.2, Rischmann P.1, Malavaud B.1, Cuvillier O.2
Ferruelo A.1, Angulo J.2, Pascual-mateo C.2, Romero I.2, Lujan M.2, Berenguer A.2 1
1
Hopital Rangueil, Urology, Toulouse, France, 2Hopital Rangueil, Inserm, Toulouse, France INTRODUCTION & OBJECTIVES: The weak incidence of prostate cancer in Asian countries made it possible for the epidemiologists to propose the green tea, and more specifically its active compound the EGCG, as a protective agent against this disease. Here we show our preliminary results obtained in vitro and in vivo concerning the antineoplastic properties of EGCG and its potential link to the sphingosine kinase (SK), an oncogenic lipid kinase overexpressed in many solid tumours. MATERIAL & METHODS: In vitro: cell viability of 2 cell human prostate cancer cell lines PC3 and PC3/SK (overexpressing SK) was studied using MTT assay. Enzymatic activity of SK in response to the EGCG was assayed. In vivo: orthotopical xenografts of PC3/GFP cells (overexpressing green fluorescent protein GFP) were established in the Nude mice. EGCG was administrated orally 3 weeks before and 3 weeks after the xenograft. Mice were sacrificed and assayed for fluorescence using digital stereomicroscopy. RESULTS: In vitro, EGCG triggers apoptosis in both LNCaP and PC-3 cell lines. This effect is correlated with SK inhibition. Demonstrating the importance of SK in the cytotoxic effect of EGCG, overexpression of SK could prevent cell death triggered by EGCG. In vivo, we fount that EGCG treatment of Nude mice orthotopically transplanted by PC-3 / GFP cells led to strong decrease in primary tumour volume as well as in the occurrence of metastases. Importantly, this effect was correlated with inhibition of SK in primary tumour samples. CONCLUSIONS: The EGCG, the principal component of the green tea, induces apoptosis in prostate cancer cells, and SK seems to be involved in its effect. P36 PROSTATE CANCER: RADIOTHERAPY AND BRACHYTHERAPY Thursday, 6 April, 14.00-15.30, Room Concorde 3 / Level 4 583 EXTERNAL BEAM RADIOTHERAPY OUTCOMES IN SEPTA- AND OCTOGENARIANS Lebeau T., Perrotte P., Bahary J.P., Saad F., Karakiewicz P.I. University of Montreal, Cancer Prognostics and Outcomes Research Unit, Montreal, Canada INTRODUCTION & OBJECTIVES: An average 70 year old male has a 12 year life expectancy (LE), a 75 year old has a 9 year LE, an 80 year old has a 7 year LE, and an 85 year old has a LE of 5 years. Based on life expectancy and comorbidity, definitive treatment of localised prostate cancer in septa- and octogenarians is controversial. We examined crude survival after definitive radiotherapy for clinically localised prostate cancer in the Province of Quebec. MATERIAL & METHODS: The RAMQ database allowed us to identify 3907 patients who were treated with definitive radiotherapy between 1989 and 2000. None received neoadjuvant hormonal therapy. None received hormonal therapy within 12 months of XRT initiation. of these, 2211 (56.6%) were 70 years of age or older and constitute the focus of this analysis. Failures corresponded to initiation of hormonal therapy. RESULTS: Of 2211 patients, 1169 (52.9) were aged 70-74 years, 741 (33.5%) were aged 75-79 years, 231 (10.4%) were aged 80-84 years and 70 (3.2%) were 85 or older. Within the 70-74 age category 61.2% died and 19.5% failed. Within the 75-79 age category 74.0% died and 17.5% failed. Within the 80-84 age category, 83.1% died and 11.3% failed. Finally, in the 85+ age category, 88.6% died and 7.1% failed.
Hospital De Getafe, Investigation-Urology, Getafe, Spain, 2Hospital Getafe, Urology, Getafe, Spain INTRODUCTION & OBJECTIVES: Epidemiological and experimental data support the role of polyphenols, compounds abundant in Mediterranean diet, for chemoprofilaxis of prostate cancer. We have evaluated the effect of different polyphenols on cell proliferation, apoptosis and androgen receptor (AR) expression in human prostate cancer LNCaP cells. MATERIAL & METHODS: LNCaP cells (5 x 102) were cultured in microtiter plate modules supplemented by5% charcoal-stripped FCS (c FCS, LINUS, Cultek) and the cells were treated with several concentrations of the following polyphenols:gallic acid, tannic acid and quercetin (1, 5 and 10 μM), rutin and morin (25, 50 and 75 μM) and resveratrol (5, 10 and 25μM). Nontreated LNCaP cells in a carrier solvent (0,1% DMSO or ethanol) were used as control. Colorimetric immunoassay method (Cell Proliferation ELISA BrdU, Roche) assessed the extent of cell proliferation at 24, 48, 72 and 96 hours. Aluminescent assay that measures caspase-3 and -7 activity (Caspase-Glo 3/7 Assay. Promega, Madison, WI, USA) was used to disclose apoptosis at 24, 48 and 72 hours. Relative quantification real-time PCR of AR mARN was achieved by real-time PCR. RESULTS: All polyphenols analysed (gallic acid, tannic acid, quercetin, rutin, morin and resveratrol) significantly inhibited LNCaP cell proliferation with respects to control (p<0.05), with moderate differences between them. Resveratrol was the strongest inhibitor at different times and doses. The weakest and latest (96 h) effect was produced by quercetin. Caspase-3 and -7 activity was also significantly higher compared to control (p<0.05) in the presence of all these polyphenols. Resveratrol increased caspase activity at 24 h and the rest at 48 h, but reached its peak with all of them at 72 h. Resveratrol, quercetin and morin -but not gallic acid, tannic acid or rutin- significantly inhibited AR mRNA expression at the same concentrations that induced caspase activity. Again, resveratrol produced the highest inhibition (88 to 275 times less than control), followed by morin and quercetin (70 to 105 and 57 to 90 times, respectively). CONCLUSIONS: The polyphenols analysed display antiproliferative effect and promote apoptosis when added to cultured LNCaP cells. Among them, resveratrol is the most potent. This and other compounds inhibit the expression of AR mRNA and that could explain, at least in part, their antiproliferative effect. The synergistic effect of these compounds and their potential to prevent progression of hormone-dependent prostate cancer merit further study.
584 INTENSITY-MODULATED RADIOTHERAPY (IMRT) FOR PROSTATE CANCER AT GHENT UNIVERSITY HOSPITAL (GUH): FIRST REPORT ON LATE TOXICITY Fonteyne V.1, Vakaet L.1, Villeirs G.2, Oosterlinck W.3, Denoyette L.1, De Neve W.1, De Meerleer G.1 1 Ghent University Hospital, Radiotherapy, Ghent, Belgium, 2Ghent University Hospital, Radiology, Ghent, Belgium, 3Ghent University Hospital, Urology, Ghent, Belgium
INTRODUCTION & OBJECTIVES: Although dose escalation to the prostate improves local control, higher doses induce an elevated risk of late gastro-intestinal (GI) and genitourinary (GU) complications. IMRT is used to decrease the dose to the prostate-surrounding normal tissues (bladder, rectum, sigmoid, small intestine), while increasing the dose to the prostate (1). This is the first report evaluating late toxicity of our IMRT technology for prostate cancer. MATERIAL & METHODS: This study includes 133 patients treated with IMRT as primary therapy for prostate cancer at GUH between December 1998 and June 2005. Median dose to the prostate (+/- seminal vesicles) was 77 Gy. GI and GU late toxicity was scored using the RTOG criteria (2), supplemented by an in-house developed toxicity scale to score GI urgency and incontinence (3). Patients were seen every 3 months for the first year, every 6 months until year 5 and annually thereafter. RESULTS: Median duration of follow-up was 36 months. Two patients had follow-up less than 3 months and were excluded from this analysis. No patient developed grade 4 toxicity. We observed grade 3 GU toxicity in 4 patients (nocturia) for a median period of 3 months. One patient experienced grade 3 red blood losses per anum (RBPA). Respectively, 19% and 17% of all patients developed grade 2 GU and GI toxicity (grade 2: possible need for oral medication). Most frequent grade 2 late GU toxicities were nocturia (20%), hematuria (18%), and GUfrequency (9%). Most frequent grade 2 late GI toxicities were RBPA (18%), abdominal cramps (6%), GI-continence (5%) and diarrhoea (5%). Except for hematuria, grade 2 side effects disappeared after a median time of 6 months. Hematuria disappeared always after increased water uptake. CONCLUSIONS: IMRT for prostate cancer causes modest levels of treatment-induced late toxicity. In half of the patients, grade 2 & 3 toxicity disappeared after 6 months.
CONCLUSIONS: A large proportion of septa- and octogenarians treated with definitive XRT do not seem to have sufficient LE to warrant such treatment. Our results suggest that the indications for definitive XRT may require a reappraisal.
Eur Urol Suppl 2006;5(2):168
References 1. De Meerleer et al. Int J Radiat Oncol Biol Phys. 2000; 47: 639-648 2. Cox et al. Int J Radiat Oncol Biol Phys. 2001; 51: 849-859. 3. De Meerleer et al. Int J Radiat Oncol Biol Phys. 2004; 60: 777-787.