Published online Mar 28, 2016. doi: 10.3748/wjg.v22.i12.3372
Peer-review started: July 4, 2015
First decision: October 15, 2015
Revised: November 8, 2015
Accepted: January 17, 2016
Article in press: January 18, 2016
Published online: March 28, 2016
Processing time: 266 Days and 16.5 Hours
AIM: To evaluate the effects of OGG1 (Ser326Cys, 11657A/G, and Arg154His) and APE1 (Asp148Glu, and T-656G) polymorphisms on colorectal cancer (CRC) risk.
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).
CONCLUSION: OGG1 and APE1 polymorphisms are associated with stage- and sex-specific risk of CRC in the Taiwanese population.
Core tip: The associations between base excision repair DNA polymorphisms and colorectal cancer (CRC) risk is controversial. The present study examined the effects of OGG1 and APE1 polymorphisms on the CRC risk by using a large-scale sample of 727 CRC cases and 736 healthy controls. Results demonstrated that OGG1 326Cys and APE1 148Glu alleles were significantly associated with an increased CRC risk in patients with stage III + IV cancer (OR = 1.48) and females (OR = 1.41). Females carrying the APE1 148Glu/-656G haplotype also exhibited a 36% increased CRC risk. These findings suggest that OGG1 and APE1 polymorphisms are associated with stage- and sex-specific risk of CRC.