An Experimental Study Of The Effect Of Potassium Iodate On The Cell Cycle Of Human Thyroid Cancer Cell

Objective: To explore the effects of potassium iodate(KIO3)with different concentrations on the cell cycle of SW579 cell,a human thyroid squamous carcinoma cell line.Methods: Proliferation and inhibition test was carried to determine the idea concentration of KIO3 to use in this study.Following 48 h co-incubation of SW579 cells with different concentrations(0,10-6,10-5,10-4,10-3,10-2? 10-1 mol/L)of KIO3,Cell counting Kit 8(CCK-8)was applied to detect the cellular proliferation activity.The cells were separated into the control group and the experimental group respectively based on experimental results.The control group(control group)was not treated with KIO3,and the group with the highest cellular metabolic activity(10-6mol/L)and the one with the declined cellular metabolic activity after administration of KIO3(10-2mol/L)were selected as experimental groups.48 h after the treatment of SW579 cells,propidium iodide(PI)single-staining flow cytometry was adopted to analyze changes of cell cycle;real-time quantitative PCR(RQ-PCR)and Western Blot method were used to detect the expression levels of messenger RNA(mRNA)and proteins in cyclin D1 and proliferating cell nuclear antigen(Ki67).Results: 1.Cellular metabolic activities of 10-6 and 10-5mol/L groups significantly enhanced,and the cellular metabolic activity of 10-6mol/L group improved relatively higher,the difference being statistically significant(P < 0.05)compared with the control group.There was no significant difference between 10-4 and 10-3mol/L groups in cellular metabolic activities,and the difference between the two groups with the control group was not statistically significant(P > 0.05).Cellular metabolic activities of 10-2 and 10-1 mol/L groups decreased(P < 0.05).2.G1 phase of cells in 10-2 group prolonged significantly(P < 0.05),and S phase shortened significantly(P < 0.05);while each phase of cells in 10-6 mol/L group changed in the opposite way(P < 0.05).3.The expression levels of cyclin and Ki67 mRNA in cells of 10-6 mol/L group were up-regulated significantly(P < 0.05),while the expression levels of cyclin and Ki67 mRNA in cells of 10-2mol/L group were down-regulated significantly(P < 0.05).4.The expression level of cyclin D1 protein in cells of 10-6mol/L group increased significantly(P < 0.05),but the increase in the expression level of intracellular Ki67 protein regulation was not statistically significant(P > 0.05);while the expression levels of intracellular cyclin D1 and Ki67 protein in 10-2mol/L group reduced significantly(P < 0.05).Conclusions: Different concentration of KIO3 have bi-direction regulation on the cell cycle of thyroid cancer cell line.Further investigation indicated that the possible mechanism maybe the regulation effect of KIO3 on cell circle protein cyclin D1.