SPARC overexpression in primary tumors correlates with disease recurrence and overall survival in patients with triple negative breast cancer

// Anjie Zhu 1 , Peng Yuan 1 , Feng Du 1 , Ruoxi Hong 2 , Xiaoyan Ding 3 , Xiuqing Shi 4 , Ying Fan 1 , Jiayu Wang 1 , Yang Luo 1 , Fei Ma 1 , Pin Zhang 1 , Qing Li 1 , Binghe Xu 1 1 Department of Medical Oncology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College(CAMS&PUMC), Beijing, China 2 Department of Medical Oncology, Sun Yat-sen University Cancer center, The State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong, China 3 Department of Medical Oncology, Beijing Ditan Hospital, Capital Medical University, Beijing, China 4 Department of Medical Oncology, Yuhuangding Hospital, Yantai, Shandong, China Correspondence to: Peng Yuan, email: yuanpengyp01@163.com Binghe Xu, email: binghxu@gmail.com Keywords: SPARC, osteonectin, triple-negative breast cancer, prognosis Received: January 12, 2016     Accepted: May 02, 2016     Published: July 11, 2016 ABSTRACT SPARC/osteonectin expression is reportedly altered in various malignancies. However, little is known regarding to the prognostic value of SPARC in triple-negative breast cancer (TNBC) patients. In this study, immunohistochemistry and immunoreactive scores (IRSs) were used to evaluate SPARC protein expression in primary tumors from 211 TNBC patients with up to 10 years of clinical follow-up data. High SPARC expression (IRS ≥3) was detected in 52.1% of primary tumors. Patients expressing high SPARC levels had worse disease-free survival (DFS) (HR=1.58, 95% CI: 1.01-2.47, P=0.044) and overall survival (OS) (HR=1.74, 95% CI: 1.06-2.85, P=0.029) than patients with lower SPARC levels. Furthermore, high SPARC expression was an independent prognostic factor for both DFS (HR=1.73, 95% CI: 1.10-2.73, P=0.018) and OS (HR=1.90, 95% CI: 1.14-3.16, P=0.014) in TNBC patients. These results suggest that increased SPARC expression may be an indicator of greater aggressiveness, and may serve as a prognostic factor for triple-negative breast cancer.