Prognostic significance of GSTP1 in patients with triple negative breast cancer

// Guanglei Chen 1, * , Hao Zhang 1, * , Lisha Sun 2, * , Yanlin Jiang 1 , Zhen Xu 1 , Huizi Gu 3 , Hong Xu 4, 5 , Jie Yang 1 , Yining Wang 1 , Tiantian Xu 1 , Yingchao Zhang 6 and Caigang Liu 1 1 Department of Breast Surgery, Shengjing Hospital of China Medical University, Shenyang 110004, China 2 Department of Surgical Oncology, The First Hospital of China Medical University, Shenyang 110013, China 3 Department of Internal Neurology, The Second Hospital of Dalian Medical University, Dalian 116027, China 4 Cancer Hospital of China Medical University, Shenyang 110042, China 5 Liaoning Cancer Hospital & Institute, Shenyang 110042, China 6 Department of Breast Surgery, The Second Hospital of JiLin University, Changchun 130041, China * Co-first authors Correspondence to: Caigang Liu, email: angel-s205@163.com Yingchao Zhang, email: Yingchaozhang770330@aliyun.com Keywords: breast cancer, GSTP1, prognosis Received: April 18, 2017     Accepted: June 28, 2017     Published: August 02, 2017 ABSTRACT Background : Previous studies showed that glutathione S-transferase Pi 1 (GSTP1) is a critical metabolic driver that is heightened specifically in triple negative breast cancer (TNBC) and drives breast cancer pathogenicity. This study focuses on investigating the relationship between the expression of the GSTP1 protein and TNBC metastasis and prognosis in China. Results: Chi-square and Fisher’s exact tests showed that tumor size (P=0.023) and clinical stage (P=0.049) were significantly associated with GSTP1 expression. Patients with high GSTP1 expression exhibited an improved survival rate compared with patients with low GSTP1 expression, but the difference was not statistically significant (P=0.437). On multivariate analysis, clinical stage proved to be an independent prognostic factor for survival in breast cancer. Materials and methods : A total of 175 patients with histologically confirmed TNBC, who also underwent radical surgery between January 2008 and November 2011 at the Liaoning Cancer Hospital, were enrolled. Immunohistochemistry was used to detect GSTP1 expression in breast cancer tissue from 175 patients. The correlations between GSTP1 expression and other parameters were evaluated using the Chi-square and Fisher’s exact tests. Univariate and multivariate Cox regression analyses were performed to assess independent prognostic factors for survival. Associations of GSTP1 expression with clinical stage and prognosis were analyzed using Kaplan–Meier survival curves. Conclusions: Tumors with high GSTP1 protein expression were independently associated with low clinical stages in TNBC patients in China. The expression of the GSTP1 protein may be a novel prognosis marker for TNBC patients in China.