Susceptibility of the human LNCaP prostate cancer cells to the apoptotic effect of marina crystal minerals (MCM) in vitro

Prostate cancer is one of the most frequent cancers among men in the United States. In the current study, we examined the susceptibility of the human LNCaP prostate cancer cells to the apoptotic effect of marina crystal minerals (MCM), a crystallized mixture of minerals and trace elements from sea water, in vitro. Cancer cells were cultured with MCM at different concentrations (0-1000 mu g/ml). At day 3, MCM exhibited a marked apoptotic effect on LNCaP cells as measured by propidium iodide (PI) and Giemsastained cytospin preparations. The apoptotic effect was dose-dependent: a 2-fold increase in the level of apoptosis over the control cells was observed at low concentrations of 50 mu g/ml, maximial (3-fold) at a concentration of 500-1000 mu g/ml. The mechanism by which MCM induces apoptosis was examined. Flow cytometery analysis demonstrated that mitochondrial membrane potential was significantly decreased post-treatment with MCM at low concentrations of 100 mu g/ml. In addition, Western blot analysis showed that the level of anti-apoptotic molecule Bcl-2 in LNCaP cells decreased upon treatment with MCM. We conclude that MCM has an apoptotic effect toward human prostate cancer cells, which may suggest its broader potential as an innovative, non-toxic anti-cancer agent.