Objective According to heparanase’s gene sequence of GenBank, to construct heparanase gene-targeted small interfering RNA (siRNA) and its expression vector and to observe its interference effect on the expression of heparanase gene in human malignant breast cancer MDA-MB-231 cell. Methods Heparanase gene-targeted hairpin siRNA was designed, two complementary oligonucleotide strands were synthesized and inserted into pGPU6/GFP/Neo vector, which was identified by sequence identify. Human malignant breast cancer MDA-MB-231 cell was transfected with the constructed vector with lipofectamine method. Fluorescence photograph was taken. Real-time PCR (RT-PCR) was performed to evaluate the level of heparanase mRNA expression. Results Four kinds of heparanase gene-targeted hairpin siRNA were designed, then were inserted into pGPU6/GFP/Neo vector after annealing. Sequencing indicated the construction was successful. Fluorescence photographs showed MDA-MB-231 cells were transfected successfully. RT-PCR showed that heparanase mRNA expression levels were inhibited significantly （Plt;0.05）. Conclusion The heparanase gene-targeted siRNA and its vector are successfully constructed and MDA-MB-231 cells are transfected successfully. Heparanase mRNA expression levels are significantly inhibited by siRNA vector, which provide a new method for the treatment of cancer.
Objective To observe the effect of gefitinib on expression of epidermal growth factor receptor (EGFR) in bile duct epithelial cells, and the feasibility of inhibiting hyperplasia of bile duct epithelial cells with gefitinib. Methods Sixty-one patients with hepatolithiasis having to be in hospital for surgery from the First People’s Hospital of Shuangliu county were selected, with 25-65 years old, average 46.92 years. The patients were randomly divided into therapy group and control group. There were 30 cases in therapy group, in which fine duct was placed on lesion bile duct during operation, and through whom gefitinib solution was perfused after operation. There were 31 cases in control group with only T tube drainage after operation. The bile duct sample was obtained respectively during the operation and 6 weeks and 12 weeks after operation. The histology and expression change of EGFR were observed by HE staining, immunohistochemistry and RT-PCR method respectively. Results There were no significant differences in pathohistology changes of bile duct and the EGFR protein and mRNA expression between therapy group and control group during operation. The hyperplasia of epithelium mucosae and submucosal gland in the therapy group were obviously decreased as compared with those in control group, the EGFR mRNA and protein expression in therapy group were weaker than those of control group （Plt;0.05） 6 weeks and 12 weeks after gefitinib treatment. Conclusion EGFR is overexpressed in the chronic proliferative cholangitis, and continuously local application of gefitinib after operation can specifically interrupt the activation and expression of EFGR and then effectively inhibit the hyperplasia of bile duct epithelial cells.