Genetic Polymorphism Of GSTP1 In Relation To Response To Oxaliplatin Based Chemotherapy And Survival In Advanced Colorectal Cancer

OBJECTIVE:To determine whether genetic polymorphism of GSTP1 Ile105Val(A→G) predict clinical outcome in Chinese patients with advanced colorectal cancer treated with oxaliplatin-based as first-line chemotherapy.METHODS:The study population consisted of 102 colorectal cancer patients in stageⅣ,DNA was extracted from peripheral venous blood before chemotherapy for every patients.GSTP1 genotypes were detected by TaqMan-MGB probe methods.Patients were treated with oxaliplatin-based chemotherapy,all patients were evaluated disease control rate(DCR) and progression free surial(PFS).RESULTS:54(52.94%)were A/A genotype,10(9.80%)were G/G genotype, and 38(37.25%)were G/A genotype.Patients possessing the G/G+G/A genotype showed a distinctly preponderance rate of 70.83%compared to 38.89%in patients harbouring A/A genotype,(χ~2=10.654,P=0.001;OR=3.816,95%CI=1.339～10.034).The median PFS of all patients was 8.3 months;G/G and G/A genotype was 10.1 months;A/A was 6.6 months.There was a significant difference between them,(χ~2=33.389,OR=3.562,P＜0.01).CONCLUSION:The GSTP1 Ile105Val polymorphism is associated with clinical outcomes of Chinese patients with advanced colorectal cancer receiving oxaliplatin-based chemotherapy as first-line.