Alpha B-crystallin C-802G polymorphism and colorectal cancer susceptibility and clinical outcome in Chinese population

Colorectal cancer (CRC) is one of the most prevalent cancers worldwide and Alpha B-crystallin (CRYAB) protein has been identified as a prognostic biomarker for CRC. We evaluated CRYAB C-802G (rs14133)polymorphism in association with CRC risk and survival in Chinese population. We genotyped for CRYAB C-802G (rs14133), A-1215G (rs2228387) and intron 2 (rs2070894), and assessed their associations with CRC in a case-control study of 441 CRC cases and 500 healthy controls. We also analyzed this polymorphism in relation to overall survival in CRC patients. A significantly different frequency distribution was found in CRYAB C-802G genotypes, but not in A-1215G and intron2 genotypes, between the cases and the controls. Under multivariable logistic regression adjusted for age and gender, CG/GG genotype carriers were associated with increased risk of CRC (OR 1.754, 95% CI 1.338–2.301, P < 0.001) when compared with CC genotype carriers. Multivariate Cox proportional hazards model showed that patients with CG/GG genotype had significant shorter survival time than those with CC genotype, after adjustment for gender and TNM stage (HR 2.347, 95% CI 1.719–3.204, P < 0.001), and after adjustment for gender and tumor grade (HR 2.871, 95% CI 2.121–3.887, P < 0.001), respectively. Our results demonstrated that CG/GG at CRYAB C-802G is correlated with CRC susceptibility and this polymorphism may be an useful marker for clinical outcome of CRC.