Delphinidin induces autophagy in HER-2+ breast cancer cells via inhibition of AKT/mTOR pathway

Abstract

To explore the effect of delphinidin on breast cancer and the underlying mechanisms. Methods: Human epidermal growth factor receptor-2 (HER-2) positive breast cancer cells MDA-MB-453 were treated by delphinidin. Proliferation of MDA-MB-453 cells was detected by CCK-8 after 48 h. TdT-mediated dUTP nick end labeling (TUNEL) assay and Western blot were used to explore apoptotic status for MDA-MB-453 cells. Fluorescence dot assay, immunofluorescence, and Western blot were used to identify autophagy in breast cancer cells. Results: Delphinidin suppressed proliferation of MDA-MB-453 cells. Delphinidin increased the number of TUNEL positive cells. Delphinidin downregulated the expression of caspase-3 and caspase-9, while upregulated the expression of cleaved caspase-3 and cleaved caspase-9 in a dose-dependent manner. Delphinidin enhanced the number of GFP-LC3 punctate dots, LC3 immunofluorescence dots and the expression of LC3-II and ATG5. Delphinidin inhibited the expression of proteins in mTOR signaling pathway, including AKT, mTOR, eIF4E and p70s6k. Conclusion: Delphinidin induced apoptosis and autophagy by inhibition of AKT/mTOR pathway in HER positive breast cancer cells.