Diospyrin derivative, an anticancer quinonoid, regulates apoptosis at endoplasmic reticulum as well as mitochondria by modulating cytosolic calcium in human breast carcinoma cells

► Diospyrin diethylether (D7) caused oxidative stress-dependent activation of PC-PLC. ► Activated PC-PLC induced a sustained-release of Ca2+ from endoplasmic reticulum. ► The elevated cytosolic Ca+2 led to the calpain-caspase12 dependent apoptosis. ► D7-Induced Ca+2 also found to accentuate the mitochondrial pathway of apoptosis.