To investigate the modulating effects of survivn antisense oligonucletode (ASODN) on the cell cycle and apoptosis of human hepatocellular carcinoma (HCC) cell line SMMC-7721 and explore its mechanism.Methods Survivin ...To investigate the modulating effects of survivn antisense oligonucletode (ASODN) on the cell cycle and apoptosis of human hepatocellular carcinoma (HCC) cell line SMMC-7721 and explore its mechanism.Methods Survivin ASODN was transfected into SMMC-7721 cells mediated by DOTAP liposomal reagent.Electron microscopy,flow cytometry and RT-PCR were used to detect the changes in cell ultrastructure,apoptosis,cell cycle and the expression of cyclinB1 mRNA,respectively.Results After transfection of survivin ASODN,the expression of cyclinB1 mRNA in the cells significantly increased and increase in G2-M arrest and apoptosis appeared.Meanwhile,the cell ultrastructure had apoptotic changes such as chromatin condensation and apoptotic body formation.Conclusion Survivin ASODN can induce the expression of cyclinB1 that may result in G2-M arrest.Consequently,apoptosis is triggered.Survivin ASODN transfection might be an improtant new treatment for HCC.14 refs,2 figs,1 tab.展开更多
Objective： To assess the anti-invasive effect of DDB and its possible active mechanism in human hepatocellular carcinoma MHCC97-H with high metastasis potential. Methods： MTT assay was used to evaluate the cytotoxic...Objective： To assess the anti-invasive effect of DDB and its possible active mechanism in human hepatocellular carcinoma MHCC97-H with high metastasis potential. Methods： MTT assay was used to evaluate the cytotoxicity of DDB to MHCC97-H cells and the anti-adhesion of DDB on MHCC97-H cells to laminin （LN） and fibronectin （FN）. The anti-invasive effect of DDB was detected by the transwell chamber experiment. VEGF, nm23-H1 and uPAR mRNA transcriptions were determined by RT-PCR assay. The secretion and expression of a-fetal protein （AFP） were analyzed by ELISA and flow cytometry, respectively. Results： DDB at non-cytotoxic concentrations （10, 50 and 100 μmol/L） obviously inhibited the adhesion of MHCC97-H on LN and FN. In the transwell chamber experiment, the inhibition rates of the invasion of DDB 50 and 100 μmol/L on MHCC97-H cells were 25.8% and 32.3%, respectively. By RT-PCR assay, DDB 50 and 100 μmol/L decreased VEGF, nm23-H1 and uPAR mRNA expressions in MHCC97-H cells. The ELISA assay showed that 50, 100 and 200 μmol/L DDB decreased the AFP secretion of MHCC97-H cells, the inhibitory rates were 16.5%, 17.5% and 48.5%, respectively. DDB also decreased the expression of AFP in MHCC97-H cells by flow cytometry assay. Conclusion： DDB, an anti-hepatitis drug, at non-cytotoxic concentrations showed significant anti-invasion effect in human hepatocellular carcinoma MHCC97-H cells, and the inhibition of VEGF, nm23-H1 and uPAR expression should contribute to the anti-invasion property of DDB.展开更多
We report the cloning and functional characterization of human cyclin L2, a novel member of the cyclin family. Human cyclin L2 shares significant homology to cyclin L1, K, T1, T2, and C, which are involved in transcri...We report the cloning and functional characterization of human cyclin L2, a novel member of the cyclin family. Human cyclin L2 shares significant homology to cyclin L1, K, T1, T2, and C, which are involved in transcriptional regulation via phosphorylation of the C-terminal domain of RNA polymerase Ⅱ. The cyclin L2 protein contains an N-terminal "cyclin box" and C-terminal dipeptide repeats of alternating arginines and serines, a hallmark of the SR family of splicing factors. A new isoform and the mouse homologue of human cyclin L2 have also been cloned in this study. Human cyclin L2 is expressed ubiquitously in normal human tissues and tumor cells. We show here that cyclin L2 co-localizes with splicing factors SC-35 and 9G8 within nuclear speckles and that it associates with hyperphosphorylated, but not hypophosphorylated, RNA polymerase Ⅱ and CDK p110 PITSLRE kinase via its N-terminal cyclin domains. It can also associate with the SC-35 and 9G8 through its RS repeat region. Recombinant cyclin L2 protein can stimulate in vitro mRNA splicing. Overexpression of human cyclin L2 suppresses the growth of human hepatocellular carcinoma SMMC 7721 cells both in vitro and in vivo, inducing cellular apoptosis. This process involves up-regulation of p53 and Bax and decreased expression of Bcl-2. The data suggest that cyclin L2 represents a new member of the cyclin family, which might regulate the transcription and RNA processing of certain apoptosis-related factors, resulting in tumor cell growth inhibition and apoptosis.展开更多
Objective： This work aimed to study the inhibitory effect and the related mechanism of metformin （MET） on the proliferation of human hepatoma HepG2 cells. Methods： Human hepatoma HepG2 cells were treated with MET ...Objective： This work aimed to study the inhibitory effect and the related mechanism of metformin （MET） on the proliferation of human hepatoma HepG2 cells. Methods： Human hepatoma HepG2 cells were treated with MET （0, 2, 10, and 50 mM）. The inhibitory effect of MET on the proliferation of HepG2 cells was determined by MTT method. The apoptosis of HepG2 cells was detected by flow cytornetry. The expression of cyclin D1 in HepG2 cells was examined by Western blot. ROS-DHE fluorescence probe was used to stain the reactive oxygen species （ROS） generated by HepG2 cells after treat- ment. Results： MET could inhibit the proliferation of HepG2 cells in a dose and time dependent manner. MET promoted the apoptosis of HepG2 cells. In addition, MET suppressed the expression of cell cycle protein cyclin D1 and induced the produc- tion of ROS in HepG2 cells. Conclusion： MET can inhibit the proliferation of human hepatoma HepG2 cells and induce cell apoptosis. Meanwhile, MET has the ability to decrease the expression of cyclin D1 and induce ROS generation, which may be involved in the mechanism of inhibiting hepatoma cells proliferation.展开更多
文摘To investigate the modulating effects of survivn antisense oligonucletode (ASODN) on the cell cycle and apoptosis of human hepatocellular carcinoma (HCC) cell line SMMC-7721 and explore its mechanism.Methods Survivin ASODN was transfected into SMMC-7721 cells mediated by DOTAP liposomal reagent.Electron microscopy,flow cytometry and RT-PCR were used to detect the changes in cell ultrastructure,apoptosis,cell cycle and the expression of cyclinB1 mRNA,respectively.Results After transfection of survivin ASODN,the expression of cyclinB1 mRNA in the cells significantly increased and increase in G2-M arrest and apoptosis appeared.Meanwhile,the cell ultrastructure had apoptotic changes such as chromatin condensation and apoptotic body formation.Conclusion Survivin ASODN can induce the expression of cyclinB1 that may result in G2-M arrest.Consequently,apoptosis is triggered.Survivin ASODN transfection might be an improtant new treatment for HCC.14 refs,2 figs,1 tab.
文摘Objective： To assess the anti-invasive effect of DDB and its possible active mechanism in human hepatocellular carcinoma MHCC97-H with high metastasis potential. Methods： MTT assay was used to evaluate the cytotoxicity of DDB to MHCC97-H cells and the anti-adhesion of DDB on MHCC97-H cells to laminin （LN） and fibronectin （FN）. The anti-invasive effect of DDB was detected by the transwell chamber experiment. VEGF, nm23-H1 and uPAR mRNA transcriptions were determined by RT-PCR assay. The secretion and expression of a-fetal protein （AFP） were analyzed by ELISA and flow cytometry, respectively. Results： DDB at non-cytotoxic concentrations （10, 50 and 100 μmol/L） obviously inhibited the adhesion of MHCC97-H on LN and FN. In the transwell chamber experiment, the inhibition rates of the invasion of DDB 50 and 100 μmol/L on MHCC97-H cells were 25.8% and 32.3%, respectively. By RT-PCR assay, DDB 50 and 100 μmol/L decreased VEGF, nm23-H1 and uPAR mRNA expressions in MHCC97-H cells. The ELISA assay showed that 50, 100 and 200 μmol/L DDB decreased the AFP secretion of MHCC97-H cells, the inhibitory rates were 16.5%, 17.5% and 48.5%, respectively. DDB also decreased the expression of AFP in MHCC97-H cells by flow cytometry assay. Conclusion： DDB, an anti-hepatitis drug, at non-cytotoxic concentrations showed significant anti-invasion effect in human hepatocellular carcinoma MHCC97-H cells, and the inhibition of VEGF, nm23-H1 and uPAR expression should contribute to the anti-invasion property of DDB.
文摘We report the cloning and functional characterization of human cyclin L2, a novel member of the cyclin family. Human cyclin L2 shares significant homology to cyclin L1, K, T1, T2, and C, which are involved in transcriptional regulation via phosphorylation of the C-terminal domain of RNA polymerase Ⅱ. The cyclin L2 protein contains an N-terminal "cyclin box" and C-terminal dipeptide repeats of alternating arginines and serines, a hallmark of the SR family of splicing factors. A new isoform and the mouse homologue of human cyclin L2 have also been cloned in this study. Human cyclin L2 is expressed ubiquitously in normal human tissues and tumor cells. We show here that cyclin L2 co-localizes with splicing factors SC-35 and 9G8 within nuclear speckles and that it associates with hyperphosphorylated, but not hypophosphorylated, RNA polymerase Ⅱ and CDK p110 PITSLRE kinase via its N-terminal cyclin domains. It can also associate with the SC-35 and 9G8 through its RS repeat region. Recombinant cyclin L2 protein can stimulate in vitro mRNA splicing. Overexpression of human cyclin L2 suppresses the growth of human hepatocellular carcinoma SMMC 7721 cells both in vitro and in vivo, inducing cellular apoptosis. This process involves up-regulation of p53 and Bax and decreased expression of Bcl-2. The data suggest that cyclin L2 represents a new member of the cyclin family, which might regulate the transcription and RNA processing of certain apoptosis-related factors, resulting in tumor cell growth inhibition and apoptosis.
文摘Objective： This work aimed to study the inhibitory effect and the related mechanism of metformin （MET） on the proliferation of human hepatoma HepG2 cells. Methods： Human hepatoma HepG2 cells were treated with MET （0, 2, 10, and 50 mM）. The inhibitory effect of MET on the proliferation of HepG2 cells was determined by MTT method. The apoptosis of HepG2 cells was detected by flow cytornetry. The expression of cyclin D1 in HepG2 cells was examined by Western blot. ROS-DHE fluorescence probe was used to stain the reactive oxygen species （ROS） generated by HepG2 cells after treat- ment. Results： MET could inhibit the proliferation of HepG2 cells in a dose and time dependent manner. MET promoted the apoptosis of HepG2 cells. In addition, MET suppressed the expression of cell cycle protein cyclin D1 and induced the produc- tion of ROS in HepG2 cells. Conclusion： MET can inhibit the proliferation of human hepatoma HepG2 cells and induce cell apoptosis. Meanwhile, MET has the ability to decrease the expression of cyclin D1 and induce ROS generation, which may be involved in the mechanism of inhibiting hepatoma cells proliferation.
