Genetic polymorphism of GSTP1 and ERCC1 correlated with response to platinum-based chemotherapy in non-small cell lung cancer.

The study aims to investigate whether the glutathione S transferase P1 (GSTP1) and excision repair cross-complementing group 1 (ERCC1) polymorphism influence the response to treatment with platinum-based chemotherapy in Chinese patients with non-small cell lung cancer. Ninety-one patients with metastatic non-small lung cancer were evaluated. Blood samples were obtained from each patient before chemotherapy. They are all administered modified TP, GP, NP regimens. Curative effects in patients were evaluated after at least two cycles of treatment. TTP was calculated. The response rate of GSTP1 with G/G + G/A group and A/A group is 54.55 % (24/44) and 21.28 % (10/47) (P = 0.001), respectively. The response rate of ERCC1 with C/C group and C/T + T/T group is 51.11 % (23/45) and 23.91 % (11/46) (P = 0.007), respectively. Patients with both G/G + G/A and C/C has the response rate of 64.52 % (20/31) (P = 0.000). Logistic regression analysis shows a significant increased chance of treatment response in patients with G/G + G/A genotype versus A/A genotype (P = 0.008) and with T/T + C/T genotype versus C/C genotype (P = 0.001). The median TTP of all patients is 7.32 months. The TTP of individuals with G/G + G/A genotype is 9.56 months, and those with A/A genotype had an TTP of 5.23 months. The TTP of individuals with C/C genotype is 9.16 months, and those with T/T + C/T genotype is 5.53 months. Kaplan-Meier analysis shows that ERCC1 and GSTP1 polymorphisms are correlated with TTP. The log-rank test is was marginally significant (P < 0.01). GSTP1 and ERCC1 polymorphism are correlated with response to platinum-based chemotherapy and have prognostic value for TTP.