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To construct recombinant plasmid and adenovirus harboring MDA-7 gene, and to investigate its biological function on the proliferation of human hepatocellular carcinoma cells.The MDA-7 fragments from the T vectors were inserted into pCDNA-3 vector to construct expression plasmids named pCDNA3-MDA-7. To determine its effects on the proliferation of HCC cells, transfected the expression vector into cells and tested the ability of colony formation in cancer cells. Simultaneously, constructed recombinant adenovirus expressing MDA-7, and detected its effect on the proliferation of HCC cells by using MTT assay.Successfully constructed plasmid- and adenovirus-based system to express MDA-7. The data of colony formation assay and M'T test showed that MDA-7 can obviously suppress cell growth in HCC cells.MDA-7 may function as tumor suppressor in HCC cells, and the adenovirus-mediated MDA-7 can be a novel strategy for the anti-HCC therapy. Our study established the foundation for future research on the effect of MDA-7 in HCC.

To construct, express and purify a human fusion protein, which is composed of a single-chain antibody fragment scFv that recognizes HER2 protein and an oligo-9-arginine, and to analyze the binding activity of the expressed fusion protein.Pairs of oligonucleotide primers were designed and used to amplify the scFv-9R. The fusion protein gene scFv-9R was then cloned into expression vector pQE30 and expressed in E.coli M15.Expressed protein was detected by SDS-PAGE and Western blot and purified by Ni-NTA chelating agarose. Then, the purified protein was refolded by dialysis and concentrated by ultrafiltration. The antigen-binding activity of the scFv-9R fusion protein was confirmed by ELISA, and the siRNA binding ability was confirmed by electrophoretic mobility shift assay (EMSA).HER2 scFv-9R encoding sequence was correctly cloned into the expression vector. The recombinant protein was insolubly expressed in E.coli M15 induced by IPTG. ELISA confirmed that it had specific antigen binding activity; EMSA assured that it had siRNA binding activity.The scFv-9R fusion protein can specially bind with both HER2 antigen and siRNA.

To construct the eukaryotic expression vector harboring transcriptional factor JunB and to observe the expression, localization and biological function of JunB in hepatic cancer cells.The JunB gene was amplified by PCR from the human liver tissue cDNA library. After confirmed by DNA sequencing in the T-vector, the JunB gene was subcloned into pcDNA3.1(-) and pEGFP-C3 vectors, respectively. The recombinant vectors pcDNA-JunB and pEGFP-JunB were confirmed by Kpn I and BamH I restriction enzyme digestion. The recombinant vectors were transiently transfected into the hepatic cancer cells HepG2 using Lipofectamin2000. Western blotting was used to detect the expression of exogenous JunB and fluorescence microscopy was applied to observe the localization of JunB protein coupled with enhanced green fluorescent protein (EGFP) in hepatic cancer cells. Double luciferase reporter assay was performed to determine the effect of JunB on the transcriptional regulation of target genes.The recombinant eukaryotic expression vector carrying JunB or JunB-EGFP fusion gene was constructed and transiently transfected into HepG2 cells. Western blot analysis confirmed the exogenous expression of JunB. JunB-EGFP was observed uniquely in the nuclei. Double luciferase assay showed the transcriptional up-regulation of the VEGF in the presence of JunB.We constructed the recombinant eukaryotic expression vectors harboring JunB and JunB-EGFP successfully. The exogenous JunB is localized in the nuclei of transiently transfected HepG2 cells, suggesting JunB may function as a transcriptional factor. The result of reporter assay showed that JunB up-regulates the expression of VEGF, a tumor-angiogenesis associated molecule, at a transcriptional level. These demonstrate that JunB might be a novel target for an anti-angiogenesis treatment for hepatic cancers.

To construct the replicative deficient adenovirus Ad-Runx3 expressing Runx3, and to express it in U251 malignant glioblastoma cells.The runx3 gene with a flag tag was amplified by PCR using pCMV5-AML2 as a template, and was confirmed by DNA sequencing. The adenovirus shuttle vector pShuttle-CMV-Runx3 was constructed by introducing runx3 DNA fragment into the sites of Kpn I and Xho I of pShuttle-CMV vector. This recombinant plasmid was linearized by PmeI and electronically transfected into BJ5183 cells to get the recombinant adenovirus vector Ad-Runx3. The recombinant adenovirus expressing Runx3 was infected into U251 malignant glioblastoma cells. The expression of exogenous Runx3 was observed by immonoblotting and its localization was detected by immunostaining using anti-Flag tag antibody.The recombinant adenovirus expressing Runx3 with a Flag tag was constructed and infected into U251 glioblastoma cells. The exogenous Runx3 protein was detected only in the nuclei.The recombinant adenovirus expressing Runx3 with a Flag tag is constructed successfully, and the Runx3 protein expressed in the nuclei of infected cells. The study laid a foundation for further research of the function of Runx3 in gliocarcinogenesis.

To explore the expression of the truncated bid gene and its pro-apoptotic effect on Hela cells.A full-length human bid gene was cloned by RT-PCR and confirmed by sequence analysis. By deleting the 60 amino acids of N-terminal the truncated bid (tbid) gene was obtained and then inserted into the eukaryotic expression vector pIRES2-EGFP. After the tbid gene was transfected into Hela cells under lipofectamine mediation, the effect of target gene expression on morphology and growth of Hela cells were observed under fluorescence and electron microscopes and analysed by TUNEL staining.pIRES2-EGFP containing tbid gene was constructed successfully. After Hela cells were transfected with GFP expression vector of tbid gene, tbid was expressed which was followed by decreased cell fluorescence intensity, poor cell growth, and cell death. Cell shrinkage and nuclear condensation, typical apoptotic characteristics, were observed by electron microscope observation and Tunel staining.The expression of tbid can effectively induce apoptosis of Hela cells.