ABSTRACT
OBJECTIVBE To investigate the intervention of compound Astragalus and Salvia milt-iorrhiza extract (CASE) consisted of astragalosides, astragalus polysaccharides and salvianolic acids on the interaction of microRNA-145/microRNA-21 (miR-145/miR-21) and Smad3C/3L phosphorylation (pSmad3C/pSmad3L) 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 Smad3C/3L phosphorylation site mutation (Smad3 3S-A/Smad3 EPSM) were used to intervene miR-145/miR-21 and pSmad3C/pSmad3L 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 3S-A plasmids in cultured dishes and xenografts of nude mice,the above effects were more evident in HepG2 cells with increased pSmad3C.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 pSmad3L and their proteins including TβRⅡ, pERK1/2, pJNK1/2 and pp38 while elevated pSmad3C expression. CONCLUSION These results suggest that pSmad3C/pSmad3L maybe interact with miR-145/miR-21 in HCC progression,which may be one of important molecular mechanisms of CASE's anti-HCC effects.
ABSTRACT
Aim To observe the effect of Salvianolic-aid B ( Sal B ) on the progression of hepatic fibrosis-carcinoma in mice induced by diethylnitrosamine ( DEN ) and investigate the mechanism of Sal B in-volved in the shift between pSmad 3 C/p21-mediated tumor suppressive signaling and pSmad 3L/PAI-1/c-Myc-mediated pro-fibrogenic/oncogenic signaling . Methods A total of 100 male Kunming mice were randomly grouped , DEN-induced hepatic fibrosis-car-cinoma model of mice was established , which was in-tragastrically treated by Sal B with two dosages ( 15 , 30 mg · kg -1 ) and colchicine with one dosage ( 0.2 mg· kg -1 ) , respectively.The mice were sacrificed at 12th week or 16th week after the start of DEN adminis-tration.Pathological changes of livers in each group were assessed by liver biopsy , hematoxylin-eosin ( HE ) staining and Van Gieson ( VG ) staining .The protein expressions of pSmad3C, pSmad3L, p21, plas-minogen activator inhibitor-1 ( PAI-1 ) and c-Myc in liver tissues were assayed by Western blot .Results In the normal control group , the surface of mouse liver was smooth and soft , and the structure of the hepatic lobule was intact.In the DEN alone group, at 12th week, the surface of mouse liver was rough and hard , the hepatic lobule was encysted or separated by colla-gen bundles, and pseudolobules emerged.At 16th week, the surface of mouse liver in the DEN alone group was rough with some nodules. HE and VG staining showed that the hepatocytes of nodules with obvious atypia and hyperchromatic nuclei were veri-fied.However, these pathological changes were evi-dently improved in Sal B treatment groups compared with the DEN group , which was proved by reductive cirrhotic nodules and alleviative fibrosis at 12th week, and decreasing cancerous nodes and ameliorative dif-ferentiation via Sal B treatment at 16th week.Western blot results showed that the protein expression of pS-mad3C, pSmad3L, PAI-1 were less, and c-Myc ex-pression was scarcely found in normal group; in DEN alone group, at 12th week, the protein expression of pSmad3C had no significant change , while the protein levels of pSmad3L, PAI-1, p21 were up-regulated, and at 16th week, the protein expressions of pS-mad3C, pSmad3L, p21, PAI-1 and c-Myc increased. In Sal B treatment group, the expressions of p21 and pSmad3C increased significantly , pSmad3L and PAI-1 protein levels markedly decreased at 12th week, the expression of pSmad3C increased obviously , p21 was almost unchanged , and the expression of pSmad 3L, PAI-1 and c-Myc were significantly reduced at 16th week .Conclusions Sal B could delay the progression of hepatic fibrosis-carcinoma in mice induced by DEN , and the mechanism may involve mediating the shift of pSmad3C/p21 and pSmad3L/PAI-1/c-Myc signaling.