The identification of caveolin and C-met interaction in hepatocellular carcinoma cell lines and tissues

ABSTRACTThe Identification of Caveolin and c-Met Interaction in HepatocellularCarcinoma Cell Lines and TissuesMurat COKAKLI, Dokuz Eylul University, School of Medicine, Department ofMedical Biology and Genetics, 35340, Balcova-Izmir, TurkeyCaveolin which is the main protein component of caveolae, interacts with severalsignaling molecules such as Ras, Epidermal Growth Factor Receptor (EGFR), and PlateletDerived Growth Factor Receptor (PDGFR). Moreover, caveolin plays important roles withdifferent expression profiles in various cancers . Many cancers are correlated with caveolin,but there is no data about the role of caveolin in Hepatocellular Carcinoma (HCC). Because ofcaveolae are an appropriate location for the signaling cascades, it is also possible that caveolininteracts with c-Met, which is Hepatocyte Growth Factor (HGF) receptor. In this study, weinvestigated the expression and interaction of caveolin and c-Met in HCC cells. Firstly, c-Metand caveolin expression levels were analyzed in several HCC cell lines. Although caveolinexpressions were only found in poorly-diferantiated cell lines but not well-differentiatedcells, c-Met expressions were found positive in all cell lines except for SNU-398. Secondly,we showed that c-met coimmunoprecipitated with caveolin under HGF induction on SNU475. Additionaly, caveolin and c-Met expressions were determined in parafin-embeddedarchive materials by immunohistochemistry, and a strong correlation was found betweencaveolin and c-Met expressions in HCC tissues.As a conclusion, it was demostrated firstly in this study that c-met interacts withcaveolin under HGF induction. Since this migth have a role in the regulation of c-Metsignalling during hepatocarcinogenesis, this study opens new insigths in the determination ofmolecular pathogenesis of disease.Key Words: caveolin, caveolae, c-Met, HGF, HCC