BCL2 and ovarian cancer: In ovarian cancer cells, TAT-fused inositol 1,4,5-trisphosphate receptor-derived peptide (TAT-IDPS), which targets the BH4 domain of Bcl-2, enhances the cytotoxicity of cisplatin by stimulating Ca2+ efflux from the endoplasmic reticulum (ER) into the cytosol and the mitochondria, which further increased cisplatin-induced ER stress-mediated apoptosis by enhancing calpain-1 expression and by activating the mitochondrial apoptotic pathway [88].