Macrophage Polarization: Anti-Cancer Strategies to Target Tumor-Associated Macrophage in Breast Cancer

Tumor-associated macrophages (TAMs) are the most abundant inflammatory cells and orchestrate different stages of breast cancer development. TAMs participate in the tumor angiogenesis, matrix remodeling, invasion, immunosuppression, metastasis, and chemoresistance in breast cancer. Several clinical studies indicate the association between the high influx of TAMs in tumor with poor prognosis in hepatocellular, ovarian, cervical, and breast cancer. Previously developed hypotheses have proposed that TAMs participate in antitumor responses of the body, while recently many clinical and experimental studies have revealed that TAMs in tumor microenvironment predominantly resemble with M2-like polarized macrophages and produce a high amount of anti-inflammatory factors which are directly responsible for the development of tumor. Various studies have shown that TAMs in tumor either enhance or antagonize the anti-tumor efficacy of cytotoxic agents, antibodies-targeting cancer cells, and therapeutic agents depending on the nature of treatment. Thereby, multiple roles of TAMs suggests that it is very important to develop novel therapeutic strategies to target TAMs in breast tumor. In this review, we have discussed the functional role of TAMs in breast cancer and summarized available recent advances potential therapeutic strategies that effectively target to TAMs cells. J. Cell. Biochem. 118: 2484-2501, 2017. © 2017 Wiley Periodicals, Inc.