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

BACKGROUND/AIMS: 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.
METHODOLOGY: 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.
RESULTS: 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).
CONCLUSIONS: 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.