Combined high expression of CD47 and CD68 is a novel prognostic factor for breast cancer patients

Abstract

Abstract Background Avoiding the phagocytosis by tumor-associated macrophages (TAMs) is necessary for the growth and metastasis of solid tumors. CD47 binds to the receptor signal-regulatory protein-α (SIRP-α) on the macrophages to avoid normal phagocytosis. In this study, we evaluated the expression and prognostic significance of CD47 and CD68-labeled TAMs in breast cancer solid tumors. Methods Two hundred seventeen cases of breast cancer tissues and 40 cases of benign breast lesions were collected for immunohistochemical staining of CD47 and CD68. Results Both of the CD47 and CD68 expression were significantly higher in breast cancer tissues (P 0.05). Interestingly, combined high expression of CD47 and CD68 (CD47highCD68high) not only had a significant association with advanced TNM stage, histological grade, LNM, ER status, PR status and recurrence (P < 0.05), but also displayed a poorer 5-DFS (P = 0.011). Strikingly, CD47highCD68high served as a novel independent prognostic factor for poor DFS compared to the expression of CD47 or CD68 alone (P = 0.045). Furthermore, our study also showed for the first time that the prognostic significance of CD47highCD68high not only in breast cancer in general, but also in hormone receptor-negative breast cancer in particular. Conclusions Combined detection of CD47 and CD68 may provide guidance for the prognosis of breast cancer, especially hormone receptor-negative breast cancer.

Keywords

• Breast cancer
• Hormone receptor-negative breast cancer
• CD47
• CD68