The Role Of Tec Acting In Signal Transduction Of Hepatoma Cell Adhesiveness Mediated By Integrinβ1

Background and objective In China,Hepatocellular carcinoma is one of the most common malignant tumor with low surgical resection and high recurrence rate,which occur latently,invase and metastasize early.Meanwhile,it is not sensitive to radiotherapy and chemotherapy,the therapeutic efficacy of liver transplantation,immunotherapy and interventional therapy is also not ideal.Nowadays,molecular biology develops rapidly, with more and more molecular mechanism on hepatic carcinoma are uncovered,molecule target therapy becomes a hopeful therapeusis to improve patient outcome Consequently,the study of molecular machanism of signal transduction in hepatic carcinoma becomes a key point.With investigating deeply on the interaction of signal protein molecule concerned with occurrence,adhesiveness,invasiveness,diffusion and metastasis of hepatic carcinoma,it becomes meaning for us to illuminate the molecule mechanism of hepatic carcinoma and discover the candidate molecular target of the capital signal protein.The adhesiveness of hepatic carcinoma cell is initial factor in the course of invasiveness and metastasis of hepatoma cell,which is the base of invasiveness and metastasis.Cell adhesiveness is mediated by a series of adhesive molecules,integrin family is a common important part of cell adhesiveness molecules.Integrin family is a heterodimers transmembrane glycoprotein, composed of aαsubunit and aβsubunit by noncovalent bond joint,and integrinβ1 subunit is the most important one in integrin family,which mainly mediate the adhesiveness of cells on ECM,accept and transconduct cascade signal to regulate vital phenomena such as survival,apoptosis and adhesiveness.There are many signal pathways and molecules in the course of adhesiveness and metastasis mediated by integrinβ1 in hepatic carcinoma,it is unknown whether Tec participate in those at present.Tec is non-receptor tyrosine protein kinase in cytoplasm,which was screened firstly from hepatic carcinoma tissue.It was confirmed that Tec is an important joint molecule of many cytokine,assistant molecule and receptor tyrosine protein kinase in the signal transduction.Tec acts with downstream substance such as Fak,Src and Erk to phosphorylate and conduct signal molecule activated by the upper stream molecule,meanwhile it takes part in and regulates many biology effect.So,we intend to confirm Tec is involved in the course of adhesiveness of hepatoma cell and to reveal the concrete molecular mechanisms by investigating the action which Tec does in the signal transduction course of hepatic carcinoma cell adhesiveness mediated by integrinβ1,and the contact between Tec and other capital adhesiveness protein,to enrich and consummate the molecular mechanism of adhesiveness in hepatoma cell.Methods1.By the method of immunocytochemistry,to detect expression of integrinβ1, Tec,Fak,Src and Erk in HepG2 hepatoma cell.2.By the method of RT-PCR and Western Blot,to detect the mRNA and protein expression of Tec,Fak,Src and Erk in HepG2 cell,before and after dealing with integrinβ1 monoclonal antibody,PP2,the inhibitor of Src,PD98059,the inhibitor of Erk.3.With the method of cell adhesiveness,MTT and siRNA interference experiment,to detect the change of hepatic carcinoma cell adhesiveness after dealing with integrinβ1 monoclonal antibody,PP2,the inhibitor of Src,PD98059,the inhibitor of Erk and TecsiRNA.Results1.Integrinβ1,Tec,Fak,Src and Erk express obviously in human HepG2 hepatoma cell.2.After dealing with different antibody,inhibitor and TecsiRNA,with the method of MTT,we find that the adhesiveness and growth of HepG2 cell is inhibited obviously with dosage dependence.3.The mRNA and protein expression of integrinβ1,Tec,Fak,Src and Erk differ obviously and appear dosage dependence in HepG2 cell after blocking with different antibody and inhibitor.Conclusion1.Tec was confirmed firstly to participate signal transduction in hepatic carcinoma cell adhesiveness.2.Tec is an important signal joint and regulation molecule in hepatic carcinoma cell adhesiveness signal transduction. 3.In the course of cell adhesiveness signal transduction mediated by integrinβ1 in hepatic carcinoma cell,Tec talks cross with other signal molecule such as Fak,Src and Erk,also it can regulate the course of hepatic carcinoma cell adhesiveness by different signal transduction molecules and signal pathways.