Enotypes present 0 1 2 P-trend135 45112 84143 1350.1.00 1.77 (0.95?.27) 13.7 (3.60?2.4) 2.24 (1.20?.18) 0.070 ,0.001 0.Abbreviations: ADT, androgen-deprivation therapy; HR, hazard ratio; 95 CI, 95 confidence interval; PSA, prostate-specific antigen. *P values were calculated using the log-rank test. { HRs were adjusted for age, clinical stage, Gleason score, PSA at ADT initiation, PSA nadir, time to PSA nadir, and treatment modality. { Unfavorable genotypes refer to CC in AKR1C3 rs12529 and longer AR CAG lengths 21 repeats. P#0.05 are in boldface. doi:10.1371/journal.pone.0054627.texpressed in prostate cancer and its expression increases with the disease progression [22,23]. AKR1C3 has also been suggested to contribute to the development of CRPC through the intratumoral formation of the active androgens [24]. Therefore, a specific inhibitor of AKR1C3 might have the potential to impact both hormone-sensitive prostate cancer and CRPC. Although the nonsynonymous polymorphism rs12529 causes a histidine to glutamine substitution at position 5 of AKR1C3, the amino acid is replaced by an amino acid of very similar chemical properties, leading to a conservative change. Nonetheless, rs12529 alters a putative exonic splicing enhancer motif that may cause alternative splicing regulatory effects, according to the prediction of FASTSNP [25]. Alternative splicing of AKR1C3 might regulate gene function and Title Loaded From File influence the efficacy of ADT. Moreover, AKR1C3 rs12529 has also been associated with lung and bladder cancer risk [26,27]. AR plays a pivotal role in prostate cancer development and progression. The factors that modify the function of AR might influence the progression of tumor to a castration-resistant state during ADT. The N-terminal transcriptional activation domain of the AR protein contains a CAG repeat, highly polymorphic in length, that affects the transactivation function of AR. Prior studies have shown an inverse relationship between CAG repeat lengthand AR transcriptional activation ability [28], and short CAG repeat lengths correlate with an increased risk of developing prostate cancer [29]. Although several studies have attempted to determine the role of AR-CAG repeat length on the outcomes of ADT, the results remain uncertain. Some studies showed that shorter CAG repeat length was correlated with better responses to hormonal therapy [30,31], an observation consistent with the present study. On the other hand, other studies found that patients with better clinical responses to ADT had a longer CAG repeat length [32,33], or in some cases, no correlation was found [34?7]. There are several possible explanations for the discrepancies in the literature. First, the measures of disease progression and the ethnic of study cohorts were different. It has been found that the prevalence of short CAG alleles was high in African-American men, intermediate in non-Hispanic whites, and low in Asians, suggesting racial differences in CAG repeat alleles. Two studies showing significantly improved responses to hormonal therapy for patients with shorter CAG repeat lengths were in Asians, Japanese [31] and Chinese (this study). Title Loaded From File Second, the contraction of CAG repeat lengths occur frequently within prostate tumors, and the lengths differ from those found in the germline samples [38]. The present and several previous studies evaluated germline AR-CAG repeat lengths in peripheral blood samples, but the actual repeatTable 4. Genotyping frequencies and the ass.Enotypes present 0 1 2 P-trend135 45112 84143 1350.1.00 1.77 (0.95?.27) 13.7 (3.60?2.4) 2.24 (1.20?.18) 0.070 ,0.001 0.Abbreviations: ADT, androgen-deprivation therapy; HR, hazard ratio; 95 CI, 95 confidence interval; PSA, prostate-specific antigen. *P values were calculated using the log-rank test. { HRs were adjusted for age, clinical stage, Gleason score, PSA at ADT initiation, PSA nadir, time to PSA nadir, and treatment modality. { Unfavorable genotypes refer to CC in AKR1C3 rs12529 and longer AR CAG lengths 21 repeats. P#0.05 are in boldface. doi:10.1371/journal.pone.0054627.texpressed in prostate cancer and its expression increases with the disease progression [22,23]. AKR1C3 has also been suggested to contribute to the development of CRPC through the intratumoral formation of the active androgens [24]. Therefore, a specific inhibitor of AKR1C3 might have the potential to impact both hormone-sensitive prostate cancer and CRPC. Although the nonsynonymous polymorphism rs12529 causes a histidine to glutamine substitution at position 5 of AKR1C3, the amino acid is replaced by an amino acid of very similar chemical properties, leading to a conservative change. Nonetheless, rs12529 alters a putative exonic splicing enhancer motif that may cause alternative splicing regulatory effects, according to the prediction of FASTSNP [25]. Alternative splicing of AKR1C3 might regulate gene function and influence the efficacy of ADT. Moreover, AKR1C3 rs12529 has also been associated with lung and bladder cancer risk [26,27]. AR plays a pivotal role in prostate cancer development and progression. The factors that modify the function of AR might influence the progression of tumor to a castration-resistant state during ADT. The N-terminal transcriptional activation domain of the AR protein contains a CAG repeat, highly polymorphic in length, that affects the transactivation function of AR. Prior studies have shown an inverse relationship between CAG repeat lengthand AR transcriptional activation ability [28], and short CAG repeat lengths correlate with an increased risk of developing prostate cancer [29]. Although several studies have attempted to determine the role of AR-CAG repeat length on the outcomes of ADT, the results remain uncertain. Some studies showed that shorter CAG repeat length was correlated with better responses to hormonal therapy [30,31], an observation consistent with the present study. On the other hand, other studies found that patients with better clinical responses to ADT had a longer CAG repeat length [32,33], or in some cases, no correlation was found [34?7]. There are several possible explanations for the discrepancies in the literature. First, the measures of disease progression and the ethnic of study cohorts were different. It has been found that the prevalence of short CAG alleles was high in African-American men, intermediate in non-Hispanic whites, and low in Asians, suggesting racial differences in CAG repeat alleles. Two studies showing significantly improved responses to hormonal therapy for patients with shorter CAG repeat lengths were in Asians, Japanese [31] and Chinese (this study). Second, the contraction of CAG repeat lengths occur frequently within prostate tumors, and the lengths differ from those found in the germline samples [38]. The present and several previous studies evaluated germline AR-CAG repeat lengths in peripheral blood samples, but the actual repeatTable 4. Genotyping frequencies and the ass.