RESUMEN
<p><b>OBJECTIVES</b>To unravel the molecular mechanism of proliferation inhibition induced by transfection of pemt2-cDNA into rat CBRH-7919 hepatoma cells.</p><p><b>METHODS</b>We started with the highly expressed PEMT2 clone. Cell culture and Western blotting techniques were used to examine the expression of cyclinD1/CDK4, cyclinE/CDK2, phospho-Rb, caspase-3, c-jun and caveolins.</p><p><b>RESULTS</b>Our results showed that CDK4, CDK2, phospho-Rb and c-jun were down regulated in the pemt2 highly expressed cell clone. The high expression clone of pemt2-transfected cells also showed over expression of caspase-3.</p><p><b>CONCLUSION</b>The reductions of proliferation and apoptosis of pemt2 transfected cells could be related to the G1 phase arrest induced by down-regulation of the cell cycle-associated proteins.</p>
Asunto(s)
Animales , Ratas , Apoptosis , Fisiología , Caspasa 3 , Genética , Quinasa 2 Dependiente de la Ciclina , Genética , Quinasa 4 Dependiente de la Ciclina , Genética , Quinasas Ciclina-Dependientes , Genética , Regulación hacia Abajo , Neoplasias Hepáticas Experimentales , Genética , Metabolismo , Fosfatidiletanolamina N-Metiltransferasa , Genética , Metabolismo , Transfección , Células Tumorales CultivadasRESUMEN
<p><b>OBJECTIVE</b>To explore the mechanism of cell proliferation inhibition by transfecting phosphatidylethanolamine N-methyltransferase 2 gene (PEMT2).</p><p><b>METHODS</b>The expression and translocation of different isoforms of protein kinase C (PKC) in cells were observed with immunocytochemistry and Western blot techniques. The content of diacylglycerol (DAG) was analyzed with high performance thin layer chromatography (HPTLC) technique.</p><p><b>RESULTS</b>Transfection of PEMT2 can inhibit the expression of cPKC alpha, but obviously promotes the expression and translocation from cytosol to plasma membrane of cPKC beta2. At the same time, the content of DAG was decreased in the transfected cells. Expression and translocation of other PKC isoforms were not changed by PEMT2 transfection.</p><p><b>CONCLUSION</b>Effects of overexpression of PEMT2 on the expression and translocation of different PKC isoforms might be related to the mechanism of cell proliferation inhibition and apoptosis induced by transfecting PEMT2.</p>