Anti-cancer Drug Anlotinib Promotes Autophagy and Apoptosis in Breast Cancer

Anlotinib, a multi-target tyrosine kinase inhibitor, has significant anti-cancer effects on breast cancer (BC), lung cancer, colon cancer and ovarian cancer, but its mechanism has not been investigated in BC.The cell viability and growth of human non-triple negative BC cell line MCF-7 and triple negative BC cell line MDA-MB-231 with the treatment of anlotinib were tested by Cell Counting Kit-8 (CCK-8) assay and Ki67 staining. The alteration of genes related to apoptosis and autophagy were investigated by quantitative real-time reverse-transcription polymerase chain reaction (qRT-PCR), western blots and immunocytochemistry (ICC). Cell apoptosis was valued by TUNEL staining and flow cytometry. Further, mouse breast tumour cell lines AT-3 cells were subcutaneously injected into C57BL/6 mice, and the effect of anlotinib intragastrically on tumour growth in vivo was examined.We found that anlotinib suppressed the cell viability and depressed Ki67 staining in MCF-7 and MDA-MB-231 cell lines. Besides, the drug also enhanced cell autophagy and apoptosis of MCF-7 and MDA-MB-231 cell lines, which could be rescued by autophagy inhibitors wortmannin (wort) and 3-methyladenine (3-MA), and BECN1 knockdown. Furthermore, Akt/GSK-3α pathway was inactivated by anlotinib treatment, while rescued by wort, 3-MA and silencing of BECN1 in the MCF-7 or MDA-MB-231 cells. We also found that anlotinib inhibited implanted tumour growth of BC in syngeneic mice.Our study demonstrated that anlotinib inhibited breast cancer cell growth in vitro and in vivo. Anlotinib promoted cell apoptosis and inactivated Akt/GSK-3α pathway of BC cells by inducing cell autophagy. It indicated that anlotinib may be an effective new drug for BC treatment.