Predictive potential role of glutathione S-transferases polymorphisms on prognosis of breast cancer.

The aim of this study was to evaluate the clinical response to chemotherapy and treatment outcome of breast cancers patients in the presence of the GSTM1 null/present, GSTT1 null/present, and GSTP1 IIe105Val polymorphisms. Genotyping of GSTP1 rs1695, GSTT1 deletion and GSTM1 deletion was carried out on a 384-well plate format on the Sequenom MassARRAY platform. Of 382 patients, 202 patients showed good response to chemotherapy, 51 died, and 155 showed progression at the end of the study. Patients carrying GG genotype and G allele of GSTP1 rs1695 were associated with poor response to chemotherapy. In the Cox proportional hazards model, after adjusting for potential confounding factors, patients carrying GG genotype and G allele of GSTP1 rs1695 were correlated with a shorter overall survival (OS). Variants of GSTP1 rs1695 are associated with response to chemotherapy and PFS and OS of breast cancer patients, and this gene polymorphism could help in the design of individualized therapy.