Effects Of Cisplatin And Povidone-iodine On Human Gastric Cancer Cell SGC-7901 Proliferation In Vitro

Objective: Cisplatin has a special mechanism on the treatment of a variety of malignant solid tumors and the price is low, thus cisplatin in clinical applications has been greatly promoted. However, part of patients exhibit congenital or acquired cisplatin resistance and cross-resistance in cancer treatment process, combined with dose-related toxicity adverse reactions and other problems. All these problems have hindered the development of cisplatin in clinical application. Povidone-iodine is mainly used for clinical disinfection preparations, and its application value remains to be further developed. In order to further broaden the clinical application of cisplatin and to further explore the clinical value of povidone-iodine,the aim of this comparative study intended to investigate the inhibition effect of DDP and in combination with povidone-iodine on human gastric cancer SGC-7901 cells proliferation in vitro. Furthermore, this experiment also intented to preliminary analyze the possible mechanisms of DDP and in combination with povidone-iodine on cell proliferation.Methods: The experiment selected human gastric cancer SGC-7901 cells as the research object, and MTT assay was used to detect the inhibition rate of different concentrations of DDP and in combination with povidone-iodine on human gastric cancer SGC-7901 cells proliferation at different times(24, 48, 72 h). Inverted phase-contrast microscope was used for preliminary observing cells morphological changes; Fluorescence microscope was used for observing cells apoptosis morphological changes by AO / EB staining; Flow cytometry was used for analyzing the changes of cell cycle and cell apoptosis rate; Western blot was used for detecting the expression of Caspase-3; Double antibody sandwich enzyme-linked immunosorbent assay(ELISA)–VI–was used for detecting the content of IL-8 in cell supernatant.Results:1 、 MTT results showed that povidone-iodine could inhibit the proliferation of human gastric cancer SGC-7901 cells and in a certain concentration range the effect became stronger with the drug concentration increased(1, 3, 6, 9 ?g/ml) and the time prolonged( 24 、 48 、 72 h). The inhibitory effect was both time dependence and concentration dependence(P<0.05); It was also found that the poliferation inhibition of DDP on human gastric cancer SGC-7901 cells showed both time dependence and concentration dependence(P<0.05). DDP at 1, 2, 4 ?g/ml combined with 3 ?g/ml povidone-iodine could synergistic inhibit the proliferation of human gastric cancer SGC-7901 cells, and the inhibition effect significantly stronger than that were treated with either of the two drugs respectively corresponding action time(24, 48, 72 h)(P<0.05). It is prompted that povidone-iodine could increase the sensitivity of gastric cancer cells to DDP.2、 The morphological changes and the emergence of apoptosis could be seen under the inverted phase-contrast microscope and fluorescence microscope.3、 Flow cytometric was used for ananlyzing cell cycle distribution. The results showed that DDP and povidone-iodine blocked cells in S phase. The proportion of cells in S phase were 28.32% 、 37.12% 、 45.06% and 25.63% separately, which were significantly higher than 21.01% in control group with a statistically difference(P < 0.05).The combination of cisplatin(2 ?g/ml) and povidone-iodine(3 ?g/ml) could also block cells in S phase. The proportion of cells in co-administration in S phase was 43.89%,significantly higher than control group and single medication group with a statistically significant difference(P < 0.05).4、 Flow cytometric was used for detecting cell apoptosis. The results showed that Cisplatin(1、2、4 ?g/ml) and povidone-iodine(3 ?g/ml) could induce cell apoptosis, and the apoptosis rates were 8.25%, 16.51%, 29.02%, 7.62% separately, which were significantly higher than 3.22% in control group. There was a statistically difference among them(P < 0.05). Apoptosis rate in co-administration was 27.28%, significantlyhigher than that of single medication group. And there also exhibited a statistically significant difference between them(P < 0.05).5 、 Western blot assay showed that cisplatin and povidone-iodine alone could increase the expression of Caspase-3, and the expression of Caspase-3 in combined-medication group was higher than that in cisplatin group and povidone-iodine group.6、 Double antibody sandwich enzyme-linked immunosorbent assay(Elisa) was used for detecting the expression of IL-8. Results showed that After treatment by cisplatin for48 h the IL-8 concentrations in the culture medium were 274.54 pg/ml、190.92 pg/ml、115.20 pg/ml and 293.48 pg/ml for povidone-iodine which were significantly reduced and the difference was statistically significant, compared with the control group 331.34pg/ml(P <0.05). Significantly lower expression in combination group 138.72 pg/ml compared with the control group and the single medication group and the difference was statistically significant(P <0.05).Conclusion:1、 Cisplatin and povidone-iodine, used alone or in combination, could inhibite the proliferation of gastric cancer cells. And the inhibition effect was more obvious along with drug concentration increased and time prolonged.2 、 Cisplatin and povidone-iodine, used alone or in combination, could down-regulate the expression of cytokine IL-8,and the mechanism might be related to drugs that inhibited cell proliferation.3 、 Cisplatin and povidone-iodine, used alone or in combination, could induce gastric cancer cells apoptosis, and the mechanism might be related to the upregulation of Caspase-3 in intracellular.