Suppression of hypoxia and inflammatory pathways by Phyllanthus niruri extract inhibits angiogenesis in DMBA-induced breast cancer mice

Abstract

BACKGROUND AND PURPOSE: extract (PNE) was reported to inhibit angiogenesis by decreasing the levels of vascular endothelial growth factor (VEGF) and hypoxia-inducible factor-1α (HIF-1α) in breast cancer. However, the experimental results were confirmed in cancer cell lines only, whereas the anti-angiogenic activity in animal models has not been demonstrated. In this study, we tried to examine the anti-angiogenic activity of PNE on BALB/c strain mice models that were induced for breast cancer using the carcinogenic substance 7,12- dimethylbenz[a]anthracene (DMBA). EXPERIMENTAL APPROACH: Experimental animals were divided into five different groups; vehicle, DMBA, PNE 500 mg/kg, PNE 1000 mg/kg; and PNE 2000 mg/kg. Mammary carcinogenesis was induced using a subcutaneous injection of 15 mg/kg of DMBA for 12 weeks. Afterward, oral PNE treatment was given for the following 5 weeks. VEGFA and HIF-1α were observed using immunohistochemistry. Endothelial cell markers CD31, CD146, and CD34 were observed using the fluorescent immunohistochemistry method. The levels of interleukin-6 (IL-6), IL-17, and C-X-C motif chemokine (CXCL12) were measured using flow cytometry. FINDINGS/RESULTS: = 0.043, log-rank test) at all doses. The PNE treatment decreased the immunoreactive score of angiogenic factors (VEGF and HIF-1α), as well as the endothelial cell markers (CD31, CD146, and CD34). The PNE- treated groups also decreased the levels of inflammatory cytokines (IL-6, IL-17, and CXCL12) at all doses. CONCLUSION AND IMPLICATIONS: This finding suggests that PNE may inhibit the progression of angiogenesis in breast cancer mice by targeting the hypoxia and inflammatory pathways.