Abstract

In this investigation, the role of autophagy and apoptosis in Solanum nigrum fruit extract-induced cytotoxicity in MDA-MB-468, a triple negative breast cancer cell line was studied. Breast cancer cells were treated with varying concentrations (1 to 5 mg/ml) of Solanum nigrum extract for 24 and 48 h. Autophagy was detected using acridine orange staining and real-time PCR for Lc3 and Beclin1 genes expression. In addition, cell apoptosis was measured by double staining, DNA fragmentation and annexin V-fluorescein isothiocyanate binding assays. The expression levels of apoptosis-related genes Bcl2 and Bax were determined by real-time PCR. Different concentrations of Solanum nigrum extract showed cytotoxic effect on MDA-MB-468 cells. The expression levels of autophagy-related genes, Lc3 and Beclin1 increased in cells treated with 1.5 mg/ml of Solanum nigrum extract. Upregulation of Bax and downregulation of Bcl2 was detected after treatment with 5 mg/ml of Solanum nigrum extract. These findings indicated that Solanum nigrum extract induced cell death in MDA-MB-468 cells by two distinct mechanisms, apoptosis and autophagy, and these findings further suggest a possibility that this extract could be used to treat triple negative breast cancer.