ABSTRACT
Aim To investigate the effect of Rhein on the movement and invasiveness of human ovarian carci-noma cells with directional high lymphatic metastasis SKOV3-PM4 cells and explore the role of Rac1/LIMK1/cofilin signaling pathway. Methods Migration assay and invasion assay were used to observe the effect of Rhein on the metastatic and invasive ability of SK-OV3-PM4 cells in vitro. The effect of Rhein on the morphology and cytoskeleton ultrastructure of ovarian cancer cells was observed by laser scanning confocal microscope and scanning electron microscope. The protein expression level of Rac1,LIMK1,PAK1 and co-filin were detected by Western blot, respectively. Re-sults Rhein inhibited the abilities of cell invasion and migration of SKOV3-PM4 cells,and the inhibitory rate increased along with the increase of the concentration and treatment duration. After treated with 8. 80 μmol· L-1 ,17. 60 μmol · L-1 , 26. 40 μmol · L-1 of Rhein for 24 h,the abilities of migration and invasion of SK-OV3-PM4 cells were inhibited ( P <0. 05 ); the mor-phology and cytoskeleton ultrastructure of SKOV3-PM4 cells were changed, cellular pseudopod reduced, cell microfilament fractured and its distribution disordered, plasma membrane was uneven and cell gap widened . After treatment of Rhein and Rac1 inhibitor , Rac1 protein expression and the expression of P-LIMK1 , P-PAK1 and P-cofilin notably decreased in a dose-de-pendent manner compared with the control group ( P<0. 05 ) . After Rhein and Rhein plus Rac1 inhibitor treatment ,P-LIMK1, P-cofilin, P-PAK1 protein levels of SKOV3-PM4 cells significantly decreased compared with the control group , and the group of Rac1 inhibi-tor plus Rhein treatment, the phosphorylated protein decreased more significantly ( P <0. 05 ) . After Rac1 activator plus Rhein treatment, phosphorylated protein expression of P-LIMK1 ,P-PAK1 and P-cofilin upregu-lated significantly ( P <0. 05 ) . Conclusions Rhein may be a potential inhibitor of Rac1 and can inhibit the migrating and invasive capabilities of directional high lymphatic metastasis SKOV3-PM4 cells through down-regulating the phosphorylation of Rac1/LIMK1 /cofilin pathway associated protein.