Compound Astragalus and Salvia miltiorrhiza extract exerts anti-tumor activity by intervening the interaction of microRNA-145/microRNA-21 and Smad3C/3L phos-phorylation in hepatocellular carcinoma

OBJECTIVBE To investigate the intervention of compound Astragalus and Salvia miltiorrhiza extract(CASE) consisted of astragalosides,astragalus polysaccharides and salvianolic acids on the interaction of microRNA-145/microRNA-21(miR-145/miR-21) and Smad3 C/3 L phosphorylation(pSmad3 C/pSmad3 L) down-stream of transforming growth factor-β(TGF-β)/mitogen activated protein kinase(MAPK) signaling in hepatocellular carcinoma(HCC) progression by in vitro and in vivo experi.ments.METHODS In HepG2 cells and xenografts of nude mice,antagomir/agomir and plasmids of Smad3 C/3 L phosphorylation site mutation(Smad3 3 S-A/Smad3 EPSM) were used to intervene miR-145/miR-21 and pSmad3 C/pSmad3 L expression respectively,then incorporative CASE treatment.Cell proliferation,migration,apoptosis,tumor growth and histopathologic characteristics of xenografts,relevant proteins of TGF-β/Smad pathway and miR-145/miR-21 were evaluated.RESULTS CASE up-regulated miR-145 while down-regulated miR-21,inhibited cell proliferation,migration and tumor growth,accelerated cell apoptosis in HepG2 cells respectively transfected with Smad3 WT,Smad3 EPSM,Smad3 3 S-A plasmids in cultured dishes and xenografts of nude mice,the above effects were more evident in HepG2 cells with increased pSmad3 C.In TGF-β1-stimulated HepG2 cells and xenografts of nude mice,CASE antagonized the facilitating effects of miR-145 antagomir/miR-21 agomir on cell migration,proliferation,tumor growth and inhibiting effects of miR-145 antagomir/miR-21 agomir on cell apoptosis;CASE increased miR-145 down-regulated by miR-145 antagomir and decreased miR-21 up-regulated by miR-21 agomir,reduced protein level of pSmad3 L and their proteins including TβRⅡ,pERK1/2,pJNK1/2 and pp38 while elevated pSmad3 C expression.CONCLUSION These results suggest that pSmad3 C/pSmad3 L maybe interact with miR-145/miR-21 in HCC progression,which may be one of important molecular mechanisms of CASE's anti-HCC effects.