Black Rice Anthocyanins Inhibit HER-2-Positive Breast Cancer Epithelial–Mesenchymal Transition And Cell Metastasis Via FAK Signaling In Vitro

It has been reported that BRACs exert an anti-metastasis effect on HER-2 positive breast cancer cells, but there is little known about its molecular mechanism related to its anti-metastasis effects. The epithelial-mesenchymal transition(EMT) is a vital biological process which has been associated with migration and metastasis of malignant tumor cells derived from epirhelial cells. FAK, an overexpressed nonrecepter kinase in human breast cancer cells, plays a vital role in various biological processes, including adhesion, migration and invasion. FAK signaling pathway and EMT exert key function in the metastasis of carcinomas. ObjectiveThe experiment aims to investigate effects BRACs play on the metastasis and EMT of HER-2 positive breast cancer MDA-MB-453 cells. Then explore the function of FAK signaling pathway on the anticancer activity. Materials and MethodsBRACs(200μg/m L) and a FAK inhibitor Y15(10μM) were used to intervent MDA-MB-453 cells.(1) The effect of BRACs on the proliferation of MDA-MB-453 cells was tested by the Cell Counting Kit-8 method.(2) The adhesion of MDA-MB-453 cells was detected by cell adhesion assay.(3) A wound-healing assay and Transwell experiment were chose to examine migration and invasion respectively.(4) Changes of cellular morphology were observed by a phase contrast microscope.(5) Western Blot was used to reflect expression level of proteins related to EMT.(6) The expression and phosphorylation of FAK signaling pathway were tested by Western Blot.(7) Association between HER-2 receptor and FAK signaling pathway was shown by immunoprecipitation. Results(1) BRACs inhibited the viability of MDA-MB-453 cells in a dose-dependent manner.(2) The adhesion of MDA-MB-453 cells was reduced by BRACs or Y15 in a dose-dependent manner.(3) BRACs or Y15 decreased the migration and invasion of MDA-MB-453 cells.(4) The morphology of MDA-MB-453 cells significantly changed from fibroblast-like to the cobblestone-like after treating with BRACs or Y15.(5) BRACs increased the expression of epithelial marker E-cadherin and decreased the expression of mesenchymal markers fibronectin and vimentin in MDA-MB-453 cells.(6) The total protein expression but the phosphorylation of cSrc, FAK, and p130 Cas have been decreased by BRACs or Y15 significantly.(7) BRACs treatment inhibited the association among HER-2, FAK, cSrc and p130 Cas.ConclusionBRACs suppress the metastasis and EMT of HER-2-positive breast cancer cells in vitro, and BRACs inhibit HER-2-positive breast cancer epithelial–mesenchymal transition and cell metastasis in vitro via FAK/cSrc/p130 Cas signaling.