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.

Objective:This study aimed to investigate the effect of human lymphatic endothelial cells (HLECs) on proteins secreted by epithelial ovarian cancer (EOC) cells SKOV3-pm4 with highly directional lymphatic metastasis. Methods:The supernatants of the four groups of cultured cells (A, SKOV3;B, SKOV3+HLEC;C, SKOV3-PM4;and D, SKOV3-PM4+HLEC) were collected. The proteins of these cells were detected by antibody arrays and iTRAQ-2D-LC-MALDI-TOF/TOF/MS. The screened significantly differential proteins were further analyzed by bioinformatics and validated in the human serum and cell culture medium by ELISA. Results:Progranulin (GRN) and vascular endothelial growth factor A (VEGF-A) were upregulated between groups C and A. In addition, insulin-like growth factor binding protein-7 (IGFBP-7) and secreted protein acid rich in cysteine (SPARC) were downregulated between groups D and C. Comprehensive bioinformatics analysis revealed that IGFBP7 interacted with VEGFA. VEGF exhibited the highest expression in ovarian cancer and IGFBP7 exhibited the lowest expression compared with the serum of the normal control group. Statistically significant differences were observed between the two substances. Conclusion:The HLEC microenvironment is closely associated with directional metastasis in lymph nodes with differential proteins, including matricellular proteins and adhesion factors. In particular, the upregulation of VEGFA and GRN and the downregulation of SPARC and IGFBP7 were closely associated with the directional metastasis of EOC cells in lymph nodes.

Objective To establish the condition cultrue cell system and co-culture cell system with SKOV3/PM4,HUVEC and to study the changes of their biological characteristics. Methods The cells of SKOV3/PM4 and HUVEC were labeled with green and red fluorescent respectively. The cell supernatant of SKOV3/PM4 and HUVEC were collected respectively as the condition medium(e.g:the cell supernatant of HUVEC cells was used as SKOV3/PM4 condition medium)and to establish the condition cultrue cell system and the co-culture cell system of the two cell lines. In the condition cultrue cell system, The morphological changes of cells were observed by HE staining to calculate the mitotic index. The ultrastructural changes of the two cells were observed by transmission electron microscopy(TEM). The growth curve of the cells was determined by methyl thiazolyl tetrazolium (MTT) assay and flow cytometry was used to analyzed the cell cycles.In the co-culture cell system, the interaction of the two cells were detected by laser scanning confocal microscope(LSCM). The expression of matrix metalloproteinase-2(MMP-2) and matrix metalloproteinase-9 (MMP-9) were detected by gelatin zymography. Results Compared with the single culture SKOV3/PM4, the cells which cultured in HUVEC condition medium showed the increase of pseudopodia and nuclear division,the mitotic index respectively were [(4.8 ± 0.8)%,(11.2 ± 0.3)%;P<0.05]. The growth rate was significantly increased. In cell cycles, it showed the declined cell ratio of G0/G1 phase, respectively[(69.4±3.6)%, (48.4±4.6)%;P<0.05] and the raised cell ratio of G2/M phase, respectively [(5.2±1.6)%, (24.9±2.2)%;P<0.05]. Compared with the single culture HUVEC,the cells which cultured in SKOV3/PM4 condition medium showed the significant morphological change and vacuolization in the cytoplasm, Nuclear division was increased and the mitotic index respectively were [(2.7±0.5)%, (5.7±0.6)%;P<0.05]. The growth rate was slightly declined. In cell cycles, it showed the raised cell ratio in G0/G1 phase, respectively [(51.4 ± 2.2)%,(79.0 ± 4.1)%;P<0.05] and the declined cell ratio in G2/M phase, respectively [(19.1±1.2)%, (3.3±0.5)%;P<0.05]. After co-culture for 48 hours, spontaneous fusion between SKOV3/PM4 and HUVEC cell was observed by the laser confocal microscope. Gelatin zymography assay showed that MMP-2 was not expressed in HUVEC cells, low-expressed in SKOV3/PM4 cells and high-expressed in the co-culture SKOV3/PM4+HUVEC cells. The expression of MMP-2 in co-culture SKOV3/PM4+HUVEC cells and SKOV3/PM4 cells respectively were 1 885 ± 84 and 1 209 ± 114 (P<0.05). But there were no MMP-9 expression in HUVEC cells, SKOV3/PM4 cells, and the co-culture SKOV3/PM4+HUVEC. Conclusion The characteristics of SKOV3/PM4 and HUVEC show significant changes after condition culture and co-culture, it may involve in the microenvironment of the cells and the intercellular crosstalk pathway.