Predictive Impact of Common Variations in DNA Repair Genes on Clinical Outcome of Osteosarcoma

We aimed to assess the role of XPG, XPC and MMS19L polymorphisms on response to chemotherapyin osteosarcomas, and the clinical outcomes. One hundred and eighty five osteosarcoma patients who werehistologically confirmed were enrolled in our study between January 2007 and December 2009. Genotyping ofXPG, XPC and MMS19L was performed in a 384-well plate format on the MassARRAY® platform. Individualswith XPG TT genotype and T allele were more likely to be better response to chemotherapy than CC genotype,with the OR (95% CI) of 4.17 (1.64-11.54) and 2.66 (1.39-5.11), respectively. Those carrying MMS19L TT genotypeand T allele showed better response to chemotherapy, with ORs (95% CI) of 4.8 (1.56-17.7) and 2.3 (1.22-4.36),respectively. Patients carrying TT genotype of XPG and MMS19L showed a significantly longer overall survivalthan CC genotype, with a 0.47 and 0.30-fold risk of death when compared with the wild-type of the gene. XPGand MMS19L are correlated with response to chemotherapy and prognosis of osteosarcoma, so that they couldbe used as predictive markers for prognosis.