Signaling and regulatory mechanisms of integrin ανβ6 on the apoptosis of colon cancer cells

Considerable researches have been done about integrin alpha nu beta 6 and carcinomas, but little information has been shown about the relationship between integrin alpha nu beta 6 nd apoptosis. In this study, we investigated the apoptosis and its related signal pathways to integrin alpha nu beta 6 in colon cancer cells. After we blocked the function of integrin alpha nu beta 6 in HT29 cells used the monoclonal antibody, the apoptotic cells increased markedly. Meanwhile, cytochrome C released from mitochondria into cytosol, Bcl-2 decreased while Bax increased significantly, and Fas and Fas-ligand had no change. The activities of caspase-3 and caspase-9 increased, while caspase-8 remained no change. Moreover, the expression of phosphorylated extracellular signal-related kinase (P-ERK) decreased. We confirmed that integrin alpha nu beta 6 acted as an important role in inhibiting apoptosis in colon cancer cells, and the signaling involved the mitochondrial pathway. (C) 2008 Elsevier Ireland Ltd. All rights reserved.