Prediction of genetic polymorphisms of DNA repair genes XRCC1 and XRCC3 in the survival of colorectal cancer receiving chemotherapy in the Chinese population.

Abstract

We aimed to detect the distribution of DNA repair genes XRCC1 and XRCC3 genotypes in the survival of colorectal cancer patients receiving chemotherapy in the Chinese population. The prospective study was conducted with 432 cases treated with 5-FU and oxaliplatin as first-line chemotherapy. All the patients were followed-up from May 2006 to May 2011 and 168 patients died during follow-up. XRCC1 and XRCC3 genotype polymorphisms were based upon the PCR-CTPP method. It was shown that the XRCC1 Arg399Gln and XRCC3 Thr241Met gene polymorphisms were associated with increased death risk of colorectal cancer. Individuals carrying XRCC1 Gln/Gln, Thr/Met and Met/Met genotypes positively associated with 2.78-, 2.86- and 3.0-fold death risk of colorectal cancer. Moreover, the combination of XRCC1 399Gln allele and XRCC3 241Met allele showed a significantly strong association with death risk of colorectal cancer (OR=3.46, 95%CI=1.65- 5.48). This study is first to report that the XRCC1 and XRCC3 gene polymorphisms are useful as a surrogate marker of clinical outcome in colorectal cancer with 5-FU/oxaliplatin combination chemotherapy in the Chinese population.