Arch Toxicol DOI 10.1007/s00204-014-1196-8
Toxicogenomics
Genetic variations in TP53 binding sites are predictors of clinical outcomes in prostate cancer patients Victor C. Lin · Chao‑Yuan Huang · Yung‑Chin Lee · Chia‑Cheng Yu · Ta‑Yuan Chang · Te‑Ling Lu · Shu‑Pin Huang · Bo‑Ying Bao
Received: 26 November 2013 / Accepted: 9 January 2014 © Springer-Verlag Berlin Heidelberg 2014
Abstract Since the tumor protein p53 (TP53), a transcription factor, plays a crucial role in prostate cancer development and progression, we hypothesized that sequence variants in TP53 binding sites might affect clinical outcomes in patients with prostate cancer. We systematically evaluated 41 single nucleotide polymorphisms (SNPs) within genome-wide predicted TP53 binding sites in a cohort of 1,024 prostate cancer patients. The associations of these SNPs with prostate cancer characteristics and clinical outcomes after radical prostatectomy for localized disease and Victor C. Lin and Chao-Yuan Huang contributed equally to this work. Electronic supplementary material The online version of this article (doi:10.1007/s00204-014-1196-8) contains supplementary material, which is available to authorized users. V. C. Lin Department of Urology, E-Da Hospital, Kaohsiung, Taiwan V. C. Lin Department of Nursing, I-Shou University, Kaohsiung, Taiwan C.-Y. Huang Department of Urology, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan Y.-C. Lee · S.-P. Huang (*) Department of Urology, Kaohsiung Medical University Hospital, 100 Ziyou 1st Road, Kaohsiung 807, Taiwan e-mail: [email protected] Y.-C. Lee · S.-P. Huang Department of Urology, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
after androgen-deprivation therapy (ADT) for advanced disease were assessed by Kaplan–Meier analysis and Cox regression model. ARAP2 rs1444377 and TRPS1 rs722740 were associated with advanced stage prostate cancer. FRK rs171866 remained as a significant predictor for disease progression; DAB2 rs268091 and EXOC4 rs1149558 remained as significant predictors for prostate cancer-specific mortality (PCSM); and EXOC4 rs1149558 remained as a significant predictor for all-cause mortality after ADT in multivariate models that included clinicopathologic predictors. In addition, the numbers of protective genotypes at DAB2 rs268091 and EXOC4 rs1149558 showed a cumulative effect on PCSM (P for trend = 0.002). Our results suggested that SNPs within TP53 binding sites might be valuable biomarkers for prostate cancer outcome prediction.
C.-C. Yu Department of Urology, School of Medicine, National YangMing University, Taipei, Taiwan C.-C. Yu Department of Pharmacy, Tajen University, Pingtung, Taiwan T.-Y. Chang Department of Occupational Safety and Health, China Medical University, Taichung, Taiwan T.-L. Lu · B.-Y. Bao (*) Department of Pharmacy, China Medical University, 91 Xueshi Road, Taichung 404, Taiwan e-mail: [email protected] B.-Y. Bao Sex Hormone Research Center, China Medical University Hospital, Taichung, Taiwan
C.-C. Yu Division of Urology, Department of Surgery, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
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Keywords Mortality · Prognosis · Prostate cancer · Single nucleotide polymorphism (SNP) · TP53 · Transcription factor binding sites Abbreviations SNP Single nucleotide polymorphism RP Radical prostatectomy ADT Androgen-deprivation therapy PCSM Prostate cancer-specific mortality ACM All-cause mortality PSA Prostate-specific antigen OR Odds ratio 95 % CI 95 % confidence interval HR Hazard ratio
Introduction Prostate cancer ranks third in cancer incidence and sixth in cancer mortality worldwide in men (Siegel et al. 2011). It has also become the fifth most common type of cancer and the seventh leading cause of cancer deaths among Taiwanese men in 2010. Although improved diagnostic techniques, such as serum prostate-specific antigen (PSA) test and digital rectal examination, appear to be effective, the detection and management of prostate cancer are still controversial (Andriole et al. 2009). The therapeutic success for prostate cancer depends heavily on the biomarkers for early detection of the presence and progression of the disease after clinical interventions. However, the most well-known clinical biomarkers for prostate cancer, including PSA level, Gleason score, and tumor-node-metastasis stage, are not ideal to distinguish patients who should be treated to stop disease progression and who should avoid overtreatment of the indolent form. Therefore, identification of novel biomarkers that could reveal further information to currently used clinical and pathological analysis is urgently needed. Tumor protein p53 (TP53), a tumor suppressor, functions as a transcription factor that tightly regulates a broad range of gene expression in response to various cellular stresses associated with carcinogenesis. Activated TP53 can elicit several cellular responses, including DNA repair, cell cycle arrest, senescence, and apoptosis (Amundson et al. 1998). For example, TP53 can cause cell cycle arrest by transcriptional activation of a cyclin-dependent kinase inhibitor, p21/Cip1, and induce apoptosis via activating the transcription of the pro-apoptotic Bcl-2 family genes, Bax, Puma, and Noxa. Loss of TP53 has been demonstrated to occur in 24 % of primary prostate tumors (Navone et al. 1993), and this alteration might contribute to aggressive tumor behavior and chemotherapy resistance (Ecke et al. 2007).
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Arch Toxicol
Sequence variants, such as single nucleotide polymorphisms (SNPs), located in the TP53 binding sites have the potential to affect the TP53-DNA interaction, resulting in altered expression of target genes. Thus, we comprehensively searched for SNPs within genome-wide predicted TP53 binding sites and investigated their associations with prostate cancer characteristics and outcomes after clinical interventions.
Materials and methods Patient recruitment and data collection All patients seen at Kaohsiung Medical University Hospital, Kaohsiung Veterans General Hospital, and National Taiwan University Hospital with a diagnosis of prostate cancer are approached to participation. A total of 1,024 prostate cancer patients diagnosed between 1995 and 2009, who had provide information and had blood collected for research purposes, were included in this study (Supplementary Table 1). The clinical data and outcomes were obtained from patients’ clinical records and pathological reports. Within the entire cohort, 321 patients with localized prostate cancer who underwent radical prostatectomy (RP) as initial treatment and 605 patients with advanced prostate cancer on androgen-deprivation therapy (ADT) were followed prospectively and have been described previously (Bao et al. 2010a, b, 2011, 2012; Chang et al. 2013; Huang et al. 2009, 2010, 2011, 2012a, b; Pao et al. 2013; Yu et al. 2013a, b). Briefly, in the RP subcohort, PSA recurrence was defined as two consecutive PSA measurements of >0.2 ng/ mL at an interval of >3 months (Freedland et al. 2003), and the PSA level of >0.2 ng/mL at the first follow-up was considered the date of recurrence. No PSA recurrence was defined as PSA persistently below 0.2 ng/mL during the post-operative follow-up period. One hundred nineteen (37.1 %) patients experienced PSA recurrence during the mean follow-up of 38.5 months (range 1–120 months). High pre-operative PSA level (>20 ng/mL), high pathologic Gleason score (8–10), locally advanced pathologic stage (T3/T4/N1), and positive surgical margin were significantly associated with shorter time to PSA recurrence after RP (data not shown). In the ADT subcohort, disease progression was defined as a serial rise in PSA, at least two rises in PSA (>1 week apart), greater than the PSA nadir (Ross et al. 2008). Initiation of secondary hormone treatment for rising PSA was also considered as a progression event. Time to progression was defined as the interval in months between the initiation of ADT and progression. Prostate cancer-specific mortality (PCSM) was defined as the interval from the initiation of ADT to death from prostate cancer. The all-cause mortality (ACM) was defined as the
Arch Toxicol Table 1 Genotyping frequencies and the association of genotype with clinical characteristics
SNP single nucleotide polymorphism, OR odds ratio, 95 % CI 95 % confidence interval P
Toxicogenomics
Genetic variations in TP53 binding sites are predictors of clinical outcomes in prostate cancer patients Victor C. Lin · Chao‑Yuan Huang · Yung‑Chin Lee · Chia‑Cheng Yu · Ta‑Yuan Chang · Te‑Ling Lu · Shu‑Pin Huang · Bo‑Ying Bao
Received: 26 November 2013 / Accepted: 9 January 2014 © Springer-Verlag Berlin Heidelberg 2014
Abstract Since the tumor protein p53 (TP53), a transcription factor, plays a crucial role in prostate cancer development and progression, we hypothesized that sequence variants in TP53 binding sites might affect clinical outcomes in patients with prostate cancer. We systematically evaluated 41 single nucleotide polymorphisms (SNPs) within genome-wide predicted TP53 binding sites in a cohort of 1,024 prostate cancer patients. The associations of these SNPs with prostate cancer characteristics and clinical outcomes after radical prostatectomy for localized disease and Victor C. Lin and Chao-Yuan Huang contributed equally to this work. Electronic supplementary material The online version of this article (doi:10.1007/s00204-014-1196-8) contains supplementary material, which is available to authorized users. V. C. Lin Department of Urology, E-Da Hospital, Kaohsiung, Taiwan V. C. Lin Department of Nursing, I-Shou University, Kaohsiung, Taiwan C.-Y. Huang Department of Urology, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan Y.-C. Lee · S.-P. Huang (*) Department of Urology, Kaohsiung Medical University Hospital, 100 Ziyou 1st Road, Kaohsiung 807, Taiwan e-mail: [email protected] Y.-C. Lee · S.-P. Huang Department of Urology, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
after androgen-deprivation therapy (ADT) for advanced disease were assessed by Kaplan–Meier analysis and Cox regression model. ARAP2 rs1444377 and TRPS1 rs722740 were associated with advanced stage prostate cancer. FRK rs171866 remained as a significant predictor for disease progression; DAB2 rs268091 and EXOC4 rs1149558 remained as significant predictors for prostate cancer-specific mortality (PCSM); and EXOC4 rs1149558 remained as a significant predictor for all-cause mortality after ADT in multivariate models that included clinicopathologic predictors. In addition, the numbers of protective genotypes at DAB2 rs268091 and EXOC4 rs1149558 showed a cumulative effect on PCSM (P for trend = 0.002). Our results suggested that SNPs within TP53 binding sites might be valuable biomarkers for prostate cancer outcome prediction.
C.-C. Yu Department of Urology, School of Medicine, National YangMing University, Taipei, Taiwan C.-C. Yu Department of Pharmacy, Tajen University, Pingtung, Taiwan T.-Y. Chang Department of Occupational Safety and Health, China Medical University, Taichung, Taiwan T.-L. Lu · B.-Y. Bao (*) Department of Pharmacy, China Medical University, 91 Xueshi Road, Taichung 404, Taiwan e-mail: [email protected] B.-Y. Bao Sex Hormone Research Center, China Medical University Hospital, Taichung, Taiwan
C.-C. Yu Division of Urology, Department of Surgery, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
13
Keywords Mortality · Prognosis · Prostate cancer · Single nucleotide polymorphism (SNP) · TP53 · Transcription factor binding sites Abbreviations SNP Single nucleotide polymorphism RP Radical prostatectomy ADT Androgen-deprivation therapy PCSM Prostate cancer-specific mortality ACM All-cause mortality PSA Prostate-specific antigen OR Odds ratio 95 % CI 95 % confidence interval HR Hazard ratio
Introduction Prostate cancer ranks third in cancer incidence and sixth in cancer mortality worldwide in men (Siegel et al. 2011). It has also become the fifth most common type of cancer and the seventh leading cause of cancer deaths among Taiwanese men in 2010. Although improved diagnostic techniques, such as serum prostate-specific antigen (PSA) test and digital rectal examination, appear to be effective, the detection and management of prostate cancer are still controversial (Andriole et al. 2009). The therapeutic success for prostate cancer depends heavily on the biomarkers for early detection of the presence and progression of the disease after clinical interventions. However, the most well-known clinical biomarkers for prostate cancer, including PSA level, Gleason score, and tumor-node-metastasis stage, are not ideal to distinguish patients who should be treated to stop disease progression and who should avoid overtreatment of the indolent form. Therefore, identification of novel biomarkers that could reveal further information to currently used clinical and pathological analysis is urgently needed. Tumor protein p53 (TP53), a tumor suppressor, functions as a transcription factor that tightly regulates a broad range of gene expression in response to various cellular stresses associated with carcinogenesis. Activated TP53 can elicit several cellular responses, including DNA repair, cell cycle arrest, senescence, and apoptosis (Amundson et al. 1998). For example, TP53 can cause cell cycle arrest by transcriptional activation of a cyclin-dependent kinase inhibitor, p21/Cip1, and induce apoptosis via activating the transcription of the pro-apoptotic Bcl-2 family genes, Bax, Puma, and Noxa. Loss of TP53 has been demonstrated to occur in 24 % of primary prostate tumors (Navone et al. 1993), and this alteration might contribute to aggressive tumor behavior and chemotherapy resistance (Ecke et al. 2007).
13
Arch Toxicol
Sequence variants, such as single nucleotide polymorphisms (SNPs), located in the TP53 binding sites have the potential to affect the TP53-DNA interaction, resulting in altered expression of target genes. Thus, we comprehensively searched for SNPs within genome-wide predicted TP53 binding sites and investigated their associations with prostate cancer characteristics and outcomes after clinical interventions.
Materials and methods Patient recruitment and data collection All patients seen at Kaohsiung Medical University Hospital, Kaohsiung Veterans General Hospital, and National Taiwan University Hospital with a diagnosis of prostate cancer are approached to participation. A total of 1,024 prostate cancer patients diagnosed between 1995 and 2009, who had provide information and had blood collected for research purposes, were included in this study (Supplementary Table 1). The clinical data and outcomes were obtained from patients’ clinical records and pathological reports. Within the entire cohort, 321 patients with localized prostate cancer who underwent radical prostatectomy (RP) as initial treatment and 605 patients with advanced prostate cancer on androgen-deprivation therapy (ADT) were followed prospectively and have been described previously (Bao et al. 2010a, b, 2011, 2012; Chang et al. 2013; Huang et al. 2009, 2010, 2011, 2012a, b; Pao et al. 2013; Yu et al. 2013a, b). Briefly, in the RP subcohort, PSA recurrence was defined as two consecutive PSA measurements of >0.2 ng/ mL at an interval of >3 months (Freedland et al. 2003), and the PSA level of >0.2 ng/mL at the first follow-up was considered the date of recurrence. No PSA recurrence was defined as PSA persistently below 0.2 ng/mL during the post-operative follow-up period. One hundred nineteen (37.1 %) patients experienced PSA recurrence during the mean follow-up of 38.5 months (range 1–120 months). High pre-operative PSA level (>20 ng/mL), high pathologic Gleason score (8–10), locally advanced pathologic stage (T3/T4/N1), and positive surgical margin were significantly associated with shorter time to PSA recurrence after RP (data not shown). In the ADT subcohort, disease progression was defined as a serial rise in PSA, at least two rises in PSA (>1 week apart), greater than the PSA nadir (Ross et al. 2008). Initiation of secondary hormone treatment for rising PSA was also considered as a progression event. Time to progression was defined as the interval in months between the initiation of ADT and progression. Prostate cancer-specific mortality (PCSM) was defined as the interval from the initiation of ADT to death from prostate cancer. The all-cause mortality (ACM) was defined as the
Arch Toxicol Table 1 Genotyping frequencies and the association of genotype with clinical characteristics
SNP single nucleotide polymorphism, OR odds ratio, 95 % CI 95 % confidence interval P
