• Journal of Life Science
• /
• v.22 no.1
• /
• pp.55-61
• /
• 2012

Akt is known to play an important role in cell proliferation and differentiation, and is also over-expressed in several types of cancer cells. In this study, we explored the anti-proliferative effects of selenium in HT-29 colon cancer cells, mediated through effects on Akt and COX-2. Selenium treatments at different concentrations and for different durations inhibited proliferation of HT-29 colon cancer cells and increased apoptotic cell death. Selenium treatment decreased Akt phosphorylation and COX-2 expression. Treatment with LY294002 (an Akt inhibitor) decreased proliferation of HT-29 cells, while a combined treatment with LY294002 and selenium resulted in even further decreases in cell proliferation. Inactivation of Akt by Akt siRNA treatment abolished these inhibitory effects on cell growth. COX-2 expression decreased in Akt transfected cells compared to non-transfected cells. These results suggest that selenium induced both anti-proliferative and apoptotic effects by inhibiting Akt phosphorylation and COX-2 expression. Selenium treatment also appeared to induce synergistic anti-proliferative effects by inhibition of Akt in HT-29 colon cancer cells.