The Role Of Hsulf-1with The STAT3Signaling In Hepatocellular Cancer Cell

Objective Hepatocellular carcinoma is one of most common cancers resultting in people death in the world, and it has increased year by year in the recent year. At present, it was cured by operation for the most part, but the treatment effect is not very ideal, so the development of new treatments is very urgent. Improvement in survival will be more dependent on better understanding of the molecular alterations related with tumorigenesis and metastasis of hepatocellular carcinoma, which is the international mainstream.The human sulfatase1(Hsulf-1), recently characterized as a heparin-degrading endosulfatase, can negatively regulate growth factor and cytokine signaling and proteolysis by way of desulfate cell surface heparan sulfate proteoglycans (HSPGs) that is the major constituent of the extracellular matrix. Heparan sulphate proteoglycans (HSPGS) can regulate several signaling pathways due to stabilizing, protectting and tansportting ligand and promotting the interactions between the receptor and the ligand, which mediates cells and microenvironment components, controls the formation, adhesion, cell proliferation and differentiation.The previous studies showed that re-expression of Hsulf-1in an ovarian cell line diminishes fibroblast growth factor (FGF-2) and heparin-binding epidermal growth factor (HB-EGF) signaling and inhibits cell proliferation and invasion in vitro. Further study of the role of Hsulf-1in tumorigenesis and progression was also found that expression of Hsulf-1inhibits the activity of HGF signaling and vascular endothelial growth factor (VEGF) signaling. Evidence indicated that STAT3signaling pathway can be actived by several growth factor receptors, such as EGFR and PDGFR, which plays a important role in cell proliferation, migration, apoptosis and angiogenesis. However, there is no report on the role of Hsulf-1in regulating the STAT3signaling pathway. This paper explored the role of Hsulf-1gene STAT3signaling pathway in hepatocellular carcinoma cells and the effect on cell growth, metastasis and apoptosis through STAT3signaling pathway that the influence of Hsulf-1on hepatocellular carcinoma development was further explored. This study certified the effect of Hsulf-1gene on STAT3signaling pathway in hepatocellular carcinoma and then explored the role of Hsulf-1on cell growth,metastasis and apoptosis through STAT3signaling pathway in hepatocellular carcinoma. Methods Hsulf-1expression was examined by RT-PCR method in hepatocellular cancer cells, and also after treated with a series of concertration of5-aza-dC and TSA in HepG2cells. In this study, We constructed the Hsulf-1expression plasmid vector and STAT3siRNA that the HepG2cells were divided into five groups, include Hsulf-1expression+STAT3siRNA transfection group, Hsulf-1expression+control siRNA group, STAT3siRNA+empty vector transfection group, control siRNA+empty vector group and untreated group. The transfected result was examined by western blotting assay. After trsnsfectting Huslf-1, the STAT3phosphorylation (p-STAT3) expression level and the content of the downstream proteins dereased. We also examined the extent of cell growth and cell metastasis by MTT method and Transwell chamber method in hepatocellular cancer cells. After cisplatin treatment, the effect of Hsulf-1on cell cycle and cell apoptosis was observed through flow cytometry instrument. Our study showed that Hsulf-1inhibited cell growth and cell metastasis and promoted cell apoptosis through STAT3signaling pathway in hepatocellular cancer cells.Results The expression level of Hsulf-1in hepatocellular carcinoma cell line (HepG2, Hep3B, Huh-7, SMMC-7221) decreased, and when HepG2cells was treated by5-aza-dC or/and TSA, the expression of Hsulf-1increased. We found that the expression level of p-STAT3significantly increased as the increac-met expression under the HGF stimulation, but after transfectting Hsulf-1expression plasmid vector, the expression level of p-STAT3decreased and also the downstream protein expression include cyclinD1and Bcl-2.We found that Hsulf-1can obviously inhibit the growth and migration of HepG2cells, blocked the GO/Gl and G2/M phase and promoted cell apoptosis comparing with the control group, and after transfectting STAT3siRNA, its effect is more obvious. It has statistical significance (p<0.01), but the STAT3does not affect Hsulf-1in HepG2blocking the G2/M phase.Conclusion1.The expression of Hsulf-1decreased in HCC cells;2. Hsulf-1can inhibit the expression of p-STAT3and downstream protein level by stimulation of HGF in hepatocellular cancer cells;3. Hsulf-1inhibited cell proliferation and metastasis in hepatocellular carcinoma cells, and at the same time whose antiproliferative effect partly due to STAT3signaling pathway mediatting by blocking the GO/G1and G2/M phase and induce cell apoptosis. but STATS signaling pathway does not affect Hsulf-1on the role of G2/M phase blocking in HepG2cells.