Increased risk of prostate cancer and benign prostatic hyperplasia associated with transforming growth factor-beta 1 gene polymorphism at codon10.

Transforming growth factor-beta 1 (TGF-beta1) plays a significant role in regulating the proliferation and apoptosis of prostate epithelial and stromal cells. We explored the association between the T (Leu) to C (Pro) polymorphism at codon10 of the TGF-beta1 gene (TGFB1) and the risk of prostate cancer (PCa) or benign prostatic hyperplasia (BPH) in 351 PCa patients, 221 BPH patients and 303 male controls in Japan. There were significant differences in the CC versus TC + TT genotype distribution between PCa patients and male controls (P=0.008), and between BPH patients and male controls (P=0.041). Males with the TC or TT genotype had a 1.62-fold increased risk of PCa [95% confidence interval (95% CI)=1.14-2.30, P=0.007] and a 1.51-fold increased risk of BPH (95% CI=1.02-2.24, P=0.041) compared with those with the CC genotype, therefore suggesting the dominant effect of the TGFB1 T allele on development of PCa and BPH. There were no significant differences in the TGFB1 genotype distribution between different groups of tumor grades and stages in the PCa patients and no significant differences when PCa patients were stratified by the age of onset. The results suggest that the codon10 polymorphism in TGFB1 may have a significant influence on the development of PCa and BPH, therefore underscoring the importance of the TGF pathway in the development of these prostatic diseases. However, it appeared to have no impact on the disease status or age of onset of PCa.