Scheme for piperine-induced inhibition of TNBC cell growth and motility. Treatment of TNBC cells with piperine inhibits cell cycle progression and induces the mitochondrial pathway of caspase-dependent apoptosis, involving the release of mitochondrial SMAC/Diablo (suppresses the function of IAPs) and cytochrome c (promotes apoptosome formation) into the cytoplasm. Piperine-mediated inhibition of MMP-2 and MMP-9 gene expression may contribute to decreased TNBC migration, which is important for metastasis.