波形蛋白真核表达质粒载体的构建及其在HepG2细胞中的表达

目的构建重组人波形蛋白中间丝真核表达质粒载体pcDNA3.1-VIM并检测波形蛋白在肝癌HepG2细胞中的稳定表达。方法通过RT-PCR技术从人胎盘组织总RNA中扩增波形蛋白基因,经限制性核酸内切酶BamHⅠ-EcoRⅠ消化,然后插入pcDNA3.1(+)载体,脂质体介导重组质粒和空质粒分别转染HepG2细胞,G418筛选稳定表达细胞株,采用免疫细胞化学技术检测目的基因的表达。结果经DNA序列分析和限制性核酸内切酶消化,证实重组载体pcDNA3.1-VIM已正确克隆,建立的稳定细胞株高表达波形蛋白。结论成功地构建了重组质粒pcDNA3.1-VIM载体和建立了稳定表达波形蛋白的人肝细胞癌细胞株,为进一步研究波形蛋白与癌细胞生物学行为之间的相互关系奠定了基础。

Effects of monoclonal antibodies against human stathmin 1 combined paclitaxel on proliferation of human hepatocellular carcinoma cell lines

Objective： We investigated the effects of monoclonal antibodies against stathmin 1 combined paclitaxel on the proliferation of HCC cells. Methods： HepG2 cells were treated with monoclonal antibodies against stathmin 1, paclitaxel alone or their combination, with the untreated cells used as the control, 24, 48, 72, 96 h later, the cell growth condition was observed by invert microscope and inhabitation rate was studied by MTT assay; The apoptosis was analyzed by flow cytometry with Annexin V/PI. Results： The population decreased and shape, size changed after treating with different concentration of experimental groups. Monoclonal antibodies against stathmin 1 and paclitaxel used alone or in combination both inhibited the proliferation of HepG2 cells, the inhibition ratio of their combination was more higher （P 〈 0.05）, and a synergistic effect of the two agents was noted in their combined action （P 〈 0.05）. Combined treatment of the cells resulted in significantly higher apoptosis rate than that in the other groups （P 〈 0.05）. Conclusion： Monoclonal antibodies against stathmin 1 and paclitaxel used alone or in combination both can inhibit proliferation of HepG2 cells and induce apoptosis. A synergistic effect is obsewed between the monoclonal antibodies against stathmin 1 and paclitaxel in their inhibition of HepG2 cell proliferation.

Growth-inhibitory effects of MOB2 on human hepatic carcinoma cell line SMMC-7721

AIM:To investigate the growth-inhibiting and apoptosis-inducing effects of the gene MOB2 on human hepatic carcinoma cell line SMMC-7721.METHODS:The full-length cDNA of the MOB2 gene was amplified from human umbilical vein endothelial cells.The correct full-length MOB2 cDNA was subcloned into the eukaryotic expression vector pEGFP-C1.After lipofection of the MOB2 gene into cancer cells,the levels of MOB2 protein in the cancer cells were detected by immunoblotting.To transfect the recombined plasmid vector pEGFP-CI-MOB2 into SMMC-7721 cells,the cells were cultured in Dulbecco's Modified Eagle'sMedium with 10% fetal calf serum and glutamine,and then mixed with liposomes,Lipofectamine 2000 and the plasmid vector pEGFP-CI-MOB2.RESULTS:We observed the growth and proliferation of SMMC-7721 cells containing pEGFP-CI-MOB2 and analyzed their apoptosis and growth cycle phases by flow cytometry.We successfully transfected the recombined plasmid vector pEGFP-CI-MOB2 into SMMC-7721 cells and screened for a single clone cell containing MOB2.After transfection,MOB2 enhanced growth suppression,induced apoptosis,increased the ratio of G0/G1,significantly inhibited the advance of cell cycle phase,and arrested cells in G0/G1 phase.CONCLUSION:MOB2 overexpression induces apoptosis and inhibits the growth of human hepatic cancer cells,which may be useful in gene therapy for hepatic carcinoma.

Celastrus orbiculatus extract induces mitochondrial-mediated apoptosis in human hepatocellular carcinoma cells

OBJECTIVE： To investigate the apoptotic effects and underlying molecular mechanisms of Celastrus orbiculatus （C. orbiculatus） extract in human hepa- tocellular carcinoma cells. METHODS： Human hepatocellular carcinoma cells （HCCLM6） were treated with C. orbiculatus extract （COE） at different nontoxic concentrations （10, 20, 40, 80, and 160 IJg/mL）. The effect of COE on HC-CLM6 viability was examined using 3-（4,5-dimethyl- thiazol-2-yl）-2,5-diphenyl tetrazolium bromide （MTT） assays. Cellular apoptosis following COE treatment was assessed by flow cytometry and western blot analysis. RESULTS： COE significantly inhibited cell viability and induced apoptosis of HCCLM6 cells in a dose-dependent manner. Apoptosis was accompa- nied by increased Bax expression and decreased Bcl-2 expression. In addition, COE treatment led to the release of cytochrome c, activation of cas- pase-3, and cleavage of poly （ADP-ribose） poly- merase （PARP）. Furthermore, activation of extracel- lular signal-regulated kinase （ERK）, p38 kinase, and c-Jun N-terminal kinase （JNK） phosphorylation, and down-regulation of Akt phosphorylation was ob- served. CONCLUSION： COE induces mitochondrial-mediat- ed, caspase-dependent apoptosis in HCCLM6 cells, which might be attributed to the activation of mito- gen-activated protein kinase （MAPK） and inhibition of Akt signaling pathways. These data suggest that COE may be a potential treatment for human hepa- tocellular carcinoma.