The Research Helicobacter Pylori Leading Gastriccancer Cell Line SGC7901 Cells To Multi Drug Resistance

Objective:To explore if helicobacter pylori could lead the gastric cancer cell to multi drug resistance(MDR).Method:The experiment is divided into two parts,Part one: Chose the best concentration of Helicobactor pylori(H.pylori) lysate and confirm the50% inhibiting concentration(IC50concentration) of the paclitaxel,Cisplatin and 5-fluorouracil.Part two:To make sure the relationship of H.pylori lysate with the multi drug resistance. After the hungering SGC7901 cells which added the H.p lysate. Using the MTT assay to get the value of OD570 of up four groups,and draw the growth curve of SGC7901 cell. Picking out the group which growth tendency is similar with the Blank group. According to the best of plasma concentration,the concentration of paclitaxel is divided into six gradient.Co-culture with SGC7901 and six concentration of three drugs.Using the MTT assay to get the value of OD570 of the up groups,get the inhibition ratio of the three drugs in different concentration to the SGC7901 cell. And compute the IC50 concentration of the up three drugs by regression analysis.The experiment is divided into Blankgroup:SGC7901;Control group: SGC7901+IC50 paclitaxel, SGC7901+IC50cisplatin, SGC7901+IC50 5-fluo-rouracil; H.p Group:SGC7901+H.p lysate+IC50 paclitaxel, SGC7901+H.p lysate+IC50, SGC7901+H.p lysate+IC505-fluorouracil.Blank group, Control group and H.p group are added the drug and H.p lysate after hungering the SGC7901 cells. Then get the value of OD570 of each group at 24h、48h、72h after hungering the SGC7901 cells.Using the MTT assay to get the value of OD570 of the up groups, and compute the inhibition ratio of each drug in IC50 concentration at each time.Using Western-Blotting experiment to measure the expression quantity of P-gp protein of SGC7901 cells in blank groups, control groups and H.p groups, then compute the value of relative gray.Using the t-test of SPSS19.0 to analyze if H.p lysate could effect the sensibility of the SGC7901 cell to drugs and the expression quantity of multi drug resistance in SGC7901 cells.Result:1.SGC7901 cells is proliferating changed to apoptosis with the concentration of the H.pylori lysate. The curve of OD570 value-time with added 5 ug/ml H.p lysate to SGC7901 cells is similar to the SGC7901 cells without H.p lysate. So choosing 5 ug/ml concentration of H.p lysate to do the experiment 2.Inhibition ratio of three groups is rise with the concentration of each drug. The value of IC50 concentration of paclitaxel,cisplatin and5-fluorouracil respectively are 5.863ug/ml、10.691ug/ml、36.375ug/ml. 3.With the IC50 concentration of paclitaxel, cisplatin, 5-fluorouracil and the H.p lysate,the inhibition ratio is rising with the concentration of the three drugs.Theinhibition ratio of three drugs to SGC7901 cells in H.p groups is lower than control groups,P<0.05, the result have statistical significance.H.p lysate can reduce the sensibility of SGC7901 cells to the paclitaxel, cisplatin,5-fluorouracil. 4.The 48 th hour after the hungering the SGC7901 cells,the expression quantity of P-gp protein of SGC7901 cells in control groups is similar with it in blank groups, P>0.05,no statistical significance.Compare the control groups and H.p groups in the same drug, the expression quantity of P-gp protein of SGC7901 cells in H.p groups is higher than the control groups,P<0.05, the the result have statistical significance. H.p lysate leading to the expression of multi drug resistance protein.Conclusion:H.p can lead gastric cancer to the expression of multi drug resistance, and reduce the sensibility of the SGC7901 cells to the drugs.