The Effects Of Rosiglitazone On Rac1-Rock/Pak1-LIMK1-Cofilin-1 Pathway In Human Gastric Cancer MGC803 Cells

Objective:To explore the molecular mechanisms of Rosiglitazone inhibiting tumor migration and invasion, we investigated the expressions' effects of rosiglitazone on Rac1-Rock/Pak1-LIMK1-cofilin-1 molecular pathways in human gastric cancer MGC803 cells.Methods: The effects of m RNA expression leve of Rac1,Rock, Pak1,LIMK1 and Cofilin-1 of rosiglitazone in human gastric cancer MGC803 cells were detected by quantitative reverse transcription polymerase chain reaction.The effects of protein expression leve of Rac1,Rock, Pak1, LIMK1 and Cofilin-1 of rosiglitazone in human gastric cancer MGC803 cells were detected by western blot.Results:1.Rosiglitazone inhibited the expression of Rac1 in human gastric cancer MGC803 cellsqRT-PCR showed that the tratements with rosiglitazone for 6h and 12 h reduced the level of Rac1 m RNA in MGC803 cells,which difference was statistically significant(p<0.05).Western blot demonstrated that when MGC803 cells were exposed to rosiglitazone for 6h,12 h and 24 h, the level of its Rac1 protein was reduced,which difference was statistically significant(p<0.05).2.Rosiglitazone inhibited the expression of Rock in human gastric cancer MGC803 cellsqRT-PCR showed that the tratements with rosiglitazone for 6h and 12 h reduced the level of Rock m RNA in MGC803 cells,which difference was statistically significant(p<0.05).Western blot demonstrated that when MGC803 cells were exposed to rosiglitazone for 6h,12 h and 24 h, the level of its Rock protein was reduced,which difference was statistically significant(p<0.05).3.Rosiglitazone inhibited the expression of Pak1 in human gastric cancer MGC803 cellsqRT-PCR showed that the tratements with rosiglitazone for 6h and 12 h reduced the level of Pak1 m RNA in MGC803 cells,which difference was statistically significant(p<0.05).Western blot demonstrated that when MGC803 cells were exposed to rosiglitazone for 6h,12 h and 24 h, the level of its Pak1 protein was reduced,which difference was statistically significant(p<0.05).4.Rosiglitazone inhibited the expression of LIMK1 in human gastric cancer MGC803 cellsqRT-PCR showed that the tratements with rosiglitazone for 6h and 12h reduced the level of LIMK1 m RNA in MGC803 cells,which difference was statistically significant(p<0.05).Western blot demonstrated that when MGC803 cells were exposed to rosiglitazone for 6h,12 h and 24 h, the level of its LIMK1 protein was reduced,which difference was statistically significant(p<0.05).5.Rosiglitazone inhibited the phosphorylation of cofilin-1 in human gastric cancer MGC803 cellsqRT-PCR showed that the tratements with rosiglitazone for 6h and 12 h in MGC803 cells, compared with control group the expression level of Cofilin-1 m RNA did not change,which difference was not statistically significant(p>0.05).Western blot showed that the tratements with rosiglitazone for 6h,12 h and 24 h in cells, compared with control group the expression level of Cofilin-1 protein had not significant change,which difference was not statistically significant(p>0.05).But the protein level of P-cofilin-1was reduced, indicating rosiglitazone inhibited the phosphorylation of cofilin-1, which difference was statistically significant(p<0.05).Conclusions:1. Rosiglitazone can down-regulate Rac1, inhibite the expression of Rock, Pak1,and LIMK1.2. Rosiglitazone has no significant effects on the expressions of Cofilin-1, but it can reduce its level of phosphorylation.3. Rosiglitazone inhibiting tumor migration and invasion may be through the signaling pathway of Rac1-Rock/ Pak1-LIMK1-Cofilin-1.