ABSTRACT
BACKGROUND: Resveratrol, a naturally occurring polyphenolic compound, has been shown to inhibit cancer growth by targeting several cancer-related signalling pathways. In the tumor microenvironment (TME), tumor-associated macrophages (TAMs) are the most abundant leukocyte population that are associated with poor prognosis in over 80% of breast cancer cases. However, little is known about the effect of resveratrol in the TME. METHODS: In this study, MDA-MB-231(MB231), cisplatin resistance MDA-MB-231 (cisR), and T47D were used to examine the antitumor effect of resveratrol. The effectiveness of resveratrol, together with cisplatin as breast cancer treatment was investigated in vivo. Gene expressions of M1 (iNOS and CXCL10) and M2 (ARG1, CD163 and MRC1) markers in differentiated macrophages derived from THP-1 cells were examined to investigate the effect of resveratrol on TAM polarization in breast cancer progression. RESULTS: Our results demonstrated that resveratrol significantly reduced cell proliferation and enhanced chemosensitivity in breast cancer cells by inhibiting production of IL-6 and STAT3 activation. Treatment of resveratrol increased CXCL10 (M1 marker) expression. Further, resveratrol decreased IL-6 levels in LPS-treated differentiated macrophages. The use of resveratrol with cisplatin inhibited suppressed tumor growth when compared with cisplatin alone. CONCLUSION: This study revealed that resveratrol inhibited breast cancer cell proliferation by promoting M1/M2 macrophage polarization ratio and suppressing IL-6/pSTAT3 pathway.