The Impact Of Silencing Of Sorcin Expression On Human Glioma Cell Sensitivity To Cisplatin

Glioma is a common central nervous system tumors of human, and whit high incidence.Most treatment of operation can not curable and drug-resistance is the key reason for the ineffectiveness of chemotherapy in gliomas.So resolve the mechanisms of glioma resistance is the key to improving the chemotherapy and it is the most important.Sorcin, soluble Resistance-related Calcium Binding Protein . Domestic and foreign studies have confirmed that sorcin can express in many MDR cells. It can combine calcium in cells, and make the intracellular calcium concentration decreased.Objective:To observe the effects of low expression of sorcin in U251 cells,the sensitivity to cisplatin.And the resistance mechanism of glioma cell.Method:1. Cell culture of U251 cells.2. Construction of a recombinant plasmid pSilencerTMneo 3.1-H1-sorcin siRNA.3. Transfection pSilencerTMneo 3.1-H1-sorcin siRNA into U251 cells.4. MTT to detected the change of the sensitivity to cisplatin in U251 cells.5. RT-PCR was used to detected the genen srocin on mRNA level and semi-quantitative Analysis.6. Western blotting was used to analyze the expression the protein of sorcin, P-gp, MRP1,Bax, Bcl-2 and caspase-3 in each group. Results:1. The plasmids pSilencerTM 3.1-H1-sorcin siRNA containing siRNA-sorcin were constructed, and confirmed by restriction enzyme digest and sequence analysis.2. Transfection with pSH1Si-sorcin into U251 cells. RT-PCR and Western blot analyses for the samples from U251 cells after transfection,the leverls of sorcin expression in U251 has been reduced.3. MTT assay indicated that that low expression of sorcin can increase the sensitivity to DDP of U251 cells and the IC50 decreased.4. Western blotting shows the result that inhibition of sorcin expression can reduce drug resistance protein P-gp and MRP1,and increase the protein of Bax/Bcl-2 and caspase3.Conclusion:Inhibited the expression of sorcin in U251 cells can increased the sensitivity to cisplatin,and sorcin is an important gene for drug resistance.The main mechanisms may be change P-gp and MRP1 gene and increase apoptosis of tumor cells.