Abstract
Objective: To explore the mechanism of Wenshen Zhuanggu Fang (, WSZG) against breast cancer bone metastasis from the perspective of macrophage polarization through bioinformatics and experiments. Methods: Bioinformatics study was used to explore the mechanism underlying the effect of WSZG on breast cancer bone metastasis. Cell viability, migration, invasion and apoptosis assays were performed to detect the influence of WSZG on breast cancer cell MDA-MB-231BO promoted by macrophages. The protein expression level and cytokine content were detected by western blot and enzyme-linked immunosorbent assay kit in vitro. Tumor growth in vivo were performed to evaluate the effects of WSZG on breast cancer bone metastasis. M2/M1 ratio and the maker protein expression were detected by flow cytometry analysis, immun-ohistochemistry and immunofluorescence double staining. Results: M2 macrophages associated with poor prognosis and may lead to secondary bone metastasis in patients with triple-negative breast cancer. WSZG could treat breast cancer bone metastasis through regulating macrophage polarization by signal transducers and transcription signaling activators (STAT) signaling pathway. WSZG downregulated STAT6, CD206 and Arginase-1, while upregulated STAT1 and Inducible Nitric Oxide Synthase, thus inhibited the M2 macrophage-promoted invasion and migration capabilities of MDA-MB-231BO cells. WSZG treatment suppressed the bone metastasis of breast cancer, and the M2/M1 ratio was reduced by regulating STAT expression in bone metastatic tissue. Conclusion: WSZG inhibited breast cancer bone metastasis by adjusting the promoting effect of macrophages on MDA-MB-231BO breast cancer cells and decreasing M2 polarization by downregulating STAT signaling.