Stabilization Of Mismatch Repair Gene PMS2 By Glycogen Synthase Kinase -3β Is Implicated In Ovarian Cancer

Objective The aim of the study was to investigate the expression of PMS2 and GSK-3βmRNA in human ovarian cancer cell lines.To examine the expression of PMS2, GSK-3βand p-GSK-3βprotein in human ovarian cancer cell lines and to analyze the correlation between PMS2 and GSK-3β. To explore the roles of GSK-3βand PMS2 in human ovarian cancer cell lines.Methods The expression of PMS2 and GSK-3βmRNA was detected by realtime reverse transcription polymerase chain reaction (realtime RT-PCR), the protein level of PMS2, GSK-3βand p-GSK-3βin human ovarain cancer cell lines A2780, Angle, NIH: OVCAR-3, Caov3 and SKOV3 was measured by Western blot. We examined PMS2, GSK-3βand phosphorylated GSK-3β(s9) (p-GSK-3β) expression in ovarian tumor tissues using immunohistochemical double staining. Human ovarain cancer cell lines were treated with LiCl for different time (0h, 12h, 24h, and 36h) and concentration (0mM, 10mM, 20mM, 40mM, and 80mM), then the cell proliferation was detected by MTT.Results PMS2 and GSK-3βmRNA were expressed in human ovarain cancer cell lines A2780, Angle, NIH: OVCAR-3, Caov3 and SKOV3, and the expression of PMS2, GSK-3βand p-GSK-3βprotein were detected in these cells. The expression of PMS2 was negatively associated with p-GSK-3β, while its mRNA level was positively correlated with GSK-3β. LiCl could suppress the proliferation of human ovarian cancer cells and showing the dose and time dependent correlation.Conclusion GSK-3βcan control the expression of PMS2, and they have roles in cancer cells survive. Objective To explore whether GSK-3βcould stabilize the expression of PMS2 in human ovarian cancer cell lines.Methods We detected PMS2 expression in five ovarian cancer cells when treated with different concentrations of LiCl and inhibited the synthesis of protein using the translational inhibitor CHX to evaluate its half-live by Western blotting. The binding of GSK-3βto PMS2 was assessed by co-immunoprecipitation (CO-IP) and immunoblotting.Results We observed that PMS2 protein levels were down-regulated significantly compared to the control (P < 0.05), showing a dose-dependent correlation. There was no evidence of cytotoxicity in either cell line after 2.5 h of treatment with 20ug/ml CHX. The half-life of PMS2 was approximately 2h in GSK-3βinhibited cells, while it did not significantly decay over a 2.5h period in HeLa cells untreated with CHX. We detected the PMS2 production in the IP complex by GSK-3β, and the GSK-3βproduction in the IP complex by PMS2, indicating a combination between GSK-3βand PMS2.Conclusion GSK-3βcan bind to the PMS2 and stabilize the expression of PMS2. Objective To investigate the role of LPS in the proliferation and migration of human ovarian cancer cell lines. To explore the roles of PMS2 and the mechanism in LPS Induced the Proliferation and Migration of Human Ovarain cancer Cell lines.Methods Human ovarain cancer cell lines treated with siTLR4 or not were incubated with LPS for different time and concentration, then the cell proliferation was examined by MTT and the migration was detected by transwell. The protein level of PMS2, p-GSK-3β, TLR4, MyD88, NFκB and IκB in LPS treated human ovarain cancer cell lines were measured by Western blot.Results We observed that LPS could augment the proliferation and encourage the migration of human ovarian cancer cell lines. When the TLR4 was interfered with siTLR4, the proliferation and migration induced by LPS were inhibited. The expression of TLR4,MyD88 and NFκB were up-regulated in LPS incubated cells, while PMS2,IκB protein levels were down-regulated compared to the control.Conclusion PMS2 maybe implicate in the proliferation and migration of human ovarain cancer cell lines induced by LPS.