Genetic Variations in a PTEN/AKT/mTOR Axis and Prostate Cancer Risk in a Chinese Population

Backgroud: Genetic variations in a PTEN/AKT/mTOR signaling axis may influence cellular functions including cell growth, proliferation and apoptosis, and then increase the individual's risk of cancer. Accordingly, we explore the association between single nucleotide polymorphisms (SNPs) of these genes and prostate cancer (PCa) in our Chinese population. Methods: Subjects were recruited from 666 PCa patients and 708 cancer-free controls, and eight SNPs in the PTEN/AKT/mTOR axis were determined by the TaqMan assay. Odds ratios (OR) and 95% confidence intervals (95% CI) were evaluated by logistic regression. Results: We observed significant associations between PCa risk and mTOR rs2295080 [P = 0.027, OR = 0.85, 95% CI = 0.74-0.98], and AKT2 rs7254617 (P = 0.003, OR = 1.35, 95% CI = 1.11-1.64). When estimated these two SNPs together, the combined genotypes with 2-4 risk alleles (rs2295080 T and rs7254617 A alleles) were associated with an increased risk of PCa compared with 0-1 risk alleles, which was more pronounced among subgroups of age >71 years, smokers, drinkers and no family history of cancer. Results of stratified analyses by cliniopathological parameters revealed that the frequencies of the combined genotypes with 2-4 risk alleles in advanced stage were significantly higher than in localized stage(P = 0.022), but there was no significant association in Gleason score and PSA level. Conclusion: Our results indicate, for the first time that the two variants in AKT2 and mTOR, particularly the joint genotypes with 2-4 risk alleles may influence PCa susceptibility and progression in Chinese, and the association appeared to be more strong in the subgroup of smokers and drinkers.