Specific interaction between Ca2+ and anionic lipids in cancer cells along with apoptosis

Abstract

Markedly inhibitory effects of Ca(2+) on the growth of human tumor cells were attained through the induction of apoptosis in vitro. On the other hand, a good correlation between the growth inhibition effects of Ca(2+) and the amounts of phosphatidylserines (PS) in the cell membranes (plasma membranes) was obtained. Furthermore, the decrease of membrane fluidity and the localization of lipid microdomains "lipid rafts" in the cell membranes were observed in the presence of Ca(2+). The findings in this study suggest that Ca(2+) could induce apoptosis toward tumor cells through the localization of lipid rafts in plasma membranes by the specific interactions between extracellular Ca(2+) and PS.