Aim
To evaluate the effects of OGG1 (Ser326Cys, 11657A/G, and Arg154His) and APE1 (Asp148Glu, and T-656G) polymorphisms on colorectal cancer (CRC) risk.
Conclusion
OGG1 and APE1 polymorphisms are associated with stage- and sex-specific risk of CRC in the Taiwanese population.
Methods
We enrolled 727 cases newly diagnosed with colorectal adenocarcinoma and 736 age- and sex-matched healthy controls from a medical center in Taiwan. Genomic DNA isolated from the buffy coat was used for genotyping through polymerase chain reaction. Unconditional logistic regressions were used for calculating ORs and 95%CIs to determine the association between the genetic polymorphisms and CRC risk. Haplotype frequencies were estimated using PHASE software. Moreover, stratification analyses on the basis of sex, age at diagnosis, and tumor subsite and stage were performed.
Results
The CRC risk was higher in patients with the OGG1 326Ser/Cys + Cys/Cys genotype (OR = 1.38, 95%CI: 1.03-1.85, P = 0.030), particularly high in patients with stage III + IV cancer (OR = 1.48, 95%CI: 1.03-2.13) compared with patients with the Ser/Ser genotype. In addition, OGG1 11657G allele carriers had a 41% reduced CRC risk among stage 0-II patients (OR = 0.59, 95%CI: 0.35-0.98). The CRC risk was significantly higher among females with the APE1 Glu allele (OR = 1.41, 95%CI: 1.02-1.96). The APE1 148Glu/-656G haplotype was also associated with a significant CRC risk in females (OR = 1.36, 95%CI: 1.03-1.78).