High expression of microRNA-454 is associated with poor prognosis in triple-negative breast cancer

// Zhi-Gang Cao 1,* , Jun-Jing Li 2,* , Ling Yao 1,* , Yan-Ni Huang 1 , Yi-Rong Liu 1 , Xin Hu 1 , Chuan-Gui Song 2 and Zhi-Ming Shao 1 1 Department of Breast Surgery, Key Laboratory of Breast Cancer in Shanghai, Fudan University Shanghai Cancer Center, Shanghai, China 2 Department of Breast Surgery, Affiliated Union Hospital, Fujian Medical University, Fuzhou, China * These authors have contributed equally to this work Correspondence to: Zhi-Ming Shao, email: // Chuan-Gui Song, email: // Keywords : microRNA-454; triple-negative breast cancer; disease-free survival; chemotherapy; in situ hybridization Received : June 21, 2016 Accepted : August 26, 2016 Published : August 31, 2016 Abstract MicroRNA-454 (miR-454) has been reported to play an oncogenic or tumor suppressor role in most cancers. However, the clinical relevance of miR-454 in breast cancer remains unclear. We examined the expression of miR-454 in a tissue microarray containing 534 breast cancer specimens from female patients at Fudan University Shanghai Cancer Center using in situ hybridization (ISH). Of these, 250 patients formed the training set and the other 284 were the validation set. The relationship between miR-454 and clinical outcome was analyzed by the Kaplan-Meier method. High expression of miR-454 indicated worse disease-free survival (DFS) in both cohorts ( P = 0.006 for training set; P = 0.010 for validation set). Furthermore, in the triple-negative breast cancer (TNBC) subtype, miR-454 was positively correlated with worse clinical outcome ( P = 0.013 for training set, P = 0.014 for validation set). In addition, patients in the low miR-454 expression cohort had better response to anthracycline compared to non-anthracycline chemotherapy ( P = 0.056), but this difference was not observed in the high miR-454 expression cohort. Our findings indicated that miR-454 is a potential predictor of prognosis and chemotherapy response in TNBC.