These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Transforming growth factor-beta 1-induced apoptosis is blocked by beta 1-integrin-mediated mitogen-activated protein kinase activation in human hepatoma cells.
    Author: Zhang H, Ozaki I, Mizuta T, Yoshimura T, Matsuhashi S, Eguchi Y, Yasutake T, Hisatomi A, Sakai T, Yamamoto K.
    Journal: Cancer Sci; 2004 Nov; 95(11):878-86. PubMed ID: 15546505.
    Abstract:
    Growth factors and extracellular matrices cooperatively regulate cellular behavior. However, the interactions between transforming growth factor-beta 1 (TGF-beta 1) and integrins in hepatic cells are not fully understood. We investigated the effects of beta 1-integrin on TGF-beta 1-regulated growth of hepatoma cells. Human hepatoma cell lines HepG2, Huh7, and Hep3B were stably transfected with beta 1-integrin, and the parental, and mock- and beta 1-integrin-transfected hepatoma cells were treated with TGF-beta 1. Modulation of apoptosis and pathways involved in the process were investigated. TGF-beta 1 suppressed the growth of hepatoma cells, and apoptosis was observed in Hep3B and Huh7. Hepatoma cells transfected with beta 1-integrin were protected from TGF-beta 1-induced apoptosis. Mitogen-activated protein (MAP) kinase inhibitors, PD98059, SB203580, and SP600125, abolished this protective effect of beta 1-integrin, but herbimycin A and wortmannin were ineffective. Hepatoma cells overexpressing beta 1-integrin showed increased activities of MAP kinases, and TGF-beta 1 induced sustained activation of MAP kinases in these cells, but only transient activation in mock-transfected cells. These data suggest that MAP kinases activated by beta 1-integrin provide a strong anti-apoptotic signal during TGF-beta 1-induced apoptosis in human hepatoma cells. Therefore beta 1-integrin-mediated signals may contribute to the development and progression of hepatocellular carcinoma.
    [Abstract] [Full Text] [Related] [New Search]