Genetic polymorphisms in glutathione‐S‐transferase genes (<i>GSTM1</i>, <i>GSTT1</i>, <i>GSTP1</i>) and survival after chemotherapy for invasive breast carcinoma

<jats:title>Abstract</jats:title><jats:sec><jats:title>BACKGROUND</jats:title><jats:p>It has been suggested that genetic polymorphisms in certain glutathione‐S‐transferase (GST) genes reduce the effectiveness of detoxifying cytotoxins generated by chemotherapeutic agents, potentially resulting in enhanced clinical responses to chemotherapy.</jats:p></jats:sec><jats:sec><jats:title>METHODS</jats:title><jats:p>The authors evaluated common polymorphisms in the <jats:italic>GSTM1</jats:italic>, <jats:italic>GSTT1</jats:italic>, and <jats:italic>GSTP1</jats:italic> genes for associations with overall survival in 1034 patients with invasive breast carcinoma who were recruited into the Shanghai Breast Cancer Study between 1996 and 1998, treated with chemotherapy, and followed for a median of 5.3 years.</jats:p></jats:sec><jats:sec><jats:title>RESULTS</jats:title><jats:p>After adjusting for age, tumor stage, and the use of radiotherapy and tamoxifen, women who were homozygous for the variant <jats:italic>GSTP1</jats:italic> <jats:sup>105</jats:sup><jats:italic>Val</jats:italic> allele had a 60% reduction in mortality risk compared with women who were homozygous for the <jats:italic>Ile</jats:italic> allele (hazard ratio, 0.4; 95% confidence interval, 0.2–0.8). No association was found with respect to any of the <jats:italic>GSTM1</jats:italic> or <jats:italic>GSTT1</jats:italic> genotypes.</jats:p></jats:sec><jats:sec><jats:title>CONCLUSIONS</jats:title><jats:p>The results of the current study indicate a potential role for <jats:italic>GSTP1</jats:italic> polymorphism in predicting the clinical outcomes of patients with breast carcinoma who are treated with chemotherapy. Cancer 2005. © 2004 American Cancer Society.</jats:p></jats:sec>