The Significance Of Non-Receptor Tyrosine Kinase Src In Metastasis Of Hepatocellular Carcinoma

Hepatocellular carcinoma(HCC) is one of the leading malignant desease in the world, ranks in three in cause of cancer death worldwide. Early-stage diagnosis and curative therapy are benificial to parts of patients, recurrence and metastasis of HCC has been the main obstacle for long-term survival. Although surgical resection could achive a5-year survival rate of50%, the postoperative recurrence is high as much as50%-80%. Therefore, effective intervention of HCC metastasis is unmet need for futher imporving porgosis. Unfortunately, there is no available effective modilites to prevent HCC metastasis though much effort has been made to explore the target moleclues involving metastasis process in wide ranges of cancer.Src kinase, one of the most ancient proto-oncogene, has been studiedits role in tumorgenesisfor many years. Recently, the much attention was focused on the Src kinase again for its novel roles in tumor recurrence and metastasis, and searched for some specific target inhibitor for Src. However, the detailed mechanism of metastasis in HCC had not been elucidated.In the present research, westudied the expression of Src kinase and its relationship with metastatic potential in HCC cell and HCC samples, and further to study the pro-metastasis role of Src kinses in HCC andunderlying machnisms. Moreover,we try to uncover the role of src kinses in chemotherapy induced deteriation of biological behavior of HCC. Our results revealed Src kinase has a important role in HCC metastasis and is a protential target to invention for reducing the metastasis of HCC and further studies are encourage to explore the Src kinase inhibitor in combination with chemotherapy or other available anti-cancer modilities.PART ONE Expression of Src kinase and its role in predicting the prognosis of HCCPurpose:To evaluate the prognostic value of Src kinase expression in recurrence and survival ofHCC patients after curative hepatectomy.Material and methods:The expression of Src,p-Src, and CD44v6were assessed by immunohistochemistry in HCC tissure microarrays from153patients, and their prognostic significance were studied with comparing their overexpression with clinicopathological data and long-term outcomes of HCC patents, patients were followed up to March.2012.Results:Univariate analysis demonstrated that p-Src expression was associated with poor overall survival (OS), time to recurrenc (TTR). However, Src or CD44v6expression had no close relationwith OS and TTR. Furthermore, multivariate analysis confirmed that dual p-Src and CD44v6overexpression was an independent predictor for OS and TTR.ConclusionThe p-Src could be a promising predictor of postoperative survival and recurrence in HCC.The p-Src combined with CD44v6could improveits diagnostic role for HCC.PART TWOThe effect of Src kinase and its mechanism in metastasis of HCCPurpose:The purpose of this study is to explore the effect the Src kinase in HCC with metastsis, and to uncover the potential mechanism through studying the expression of Src kinase in HCC cell line and in animal model of HCC with lung metastasis.Methods:We tested the function of HCC cells involving in proliferation, migration, invision, clony forming processes invitro and the expression of p-Src、p-FAK、p-Stat3using Src kinase inhibitor-Saracatinib, we compared the tumor size and lung metastasis in MHCC97H inoculated xenograft nude modle of HCC.Reslults:The expressions of Src kinase were different in these three cells. The highest in MHCC97H cells, the lowest in L02cells. The function of cell proliferation, migration, invision, clony forming processes were inhibited in vivousing inhibitor of Src kinase. Inhibition of Src kinase can suppress the lung metastasis in nude model. While the inhibition of p-Src kinase,the expressions of p-FAK and p-Stat3were decreased spontaneously.Conclusion:The expression of Src kinase was associated with the metastasis potential of HCC cells. Inhibition of Src activity can suppress lung metastasis of HCC. Src kinase regulated the metastasis of HCC through the p-Src-p-FAK-p-Stat3axis.PART THREEThe effect and mechanism of Src kinase in regulating the increasing metastatic potential induced by oxaliplation in HCC Oxaliplatin induced the metastatic potential in HCC cells Purpose:To evaluate the metastatic potential of HCC after treatment of oxaliplatin and elucidate the underlying machenisms.Methods:MHCC-97H and Hep3B cells were treated with stemwiseincreased the concentration of oxaliplatin and established descendant cell lines of FD-MHCC-97H-OXA and FD-Hep3B-OXA. The metastatic potential of cells was evaluated for proliferation, migration and invasion in vitro and in vivo.Results:HCC cells treated with oxaliplatin showed morphologicalchanges from epithelial-like to mensenchyma-like with enhanced metastatic potential. Comparing with parent cells phosphor-Src, phosphor-FAK, phosphor-Stat3and epithelial mesenchymal transition (EMT) markers were significantely induced. In nude models, oxaliplatin induced HCC cells FD-MHCC-97H-OXA tumor was much large and with significantely increased lung metastasis potential than parent cell MHCC-97H.Conclusion:Oxaliplatin can induce the increasing metastatic potential in HCC cells via the overexpression of p-Src, p-FAK and p-Stat3signal pathway through induction of EMT.Inhibition of Src kinase can reverse the increasing metastatic potential in HCC cells induced by oxaliplatinObjective:The aim of this study is to clarify whether the inhibition of Src kinase can reverse the enhanced metastatic potential induced by oxaliplatin.Methods:we used the inhibitor of Src kinase to suppress the activation of Src kinase, and then tested the expression of p-Src, p-FAK, p-Stat3, E-cadherin, and Vimentin by westerblotting. Also, we treated the nude modle inoculated by oxaliplatin-induced HCC cells with inhibitor of Src kinase to observe the tumor size and lung metastasis in vivo.Results:The inhibitor of Src kinase can suppress the expression of p-src, p-FAK and p-Stat3; reversed the EMT and inhibited the lung metastasis of oxaliplatin induced FD-MHCC-97H-OXA in nude mice. The results revealed that Src kinase involved oxaliplatin induced deterioration of metastasis potential in HCC.Conclusion:The inhibition of Src kinase can reverse the enhanced metastatic potential induced by oxaliplatin. It is suggested that suppression of activation p-Src could reverse EMT process to decrease the metastatic potential induced by chemotherapy.