Study On The Activation Of PAR2 And The Mechanisms Of SW620 Cell Proliferation And Migration Induced By TF-VIIa

Objective:To investigate the effects of coagulation factorâ…¦a,â…©andâ…¡a in the activation of protease-activated receptor-2(PAR2) and the mechanisms of colon cancer cell line SW620 proliferation and migration induced by TF-â…¦a,as well as the signal transduction pathway involved in the process.Methods:SW620 cells were treated with different stimulants including PAR2 agonist(PAR2-AP),factorâ…¦a,â…©,â…¡a and anti-TF(tissue factor) or anti-PAR2 antibodies,then the interleukin 8(IL-8) secreted by cells was detected by the method of ELISA.The effects of PAR2 activation by different coagulation factors were evaluated according to the levels of IL-8 expression.Futhermore,the expression of IL-8,TF and caspase-7 in SW620 cells induced by TF-â…¦a was analyzed using Q-PCR(for mRNA level),ELISA(for protein level) and TF activity kits(for TF activity). Finally,the level of p-p38 MAPK with different stimulation was detected by Western-blotting.The mechanisms of SW620 cell proliferation and migration induced by TF-â…¦a were primarily evaluated accordong to the changes of IL-8,TF and caspase-7 expressiom,as well as p38 MAPK phosphorylation.Results:(1) Factorâ…¦a,at plasma concentration of 100 pM, combined with factorâ…©(100 nM) could induce IL-8 secretion in SW620 cells.Such effects of TF-â…¦a-â…©could be blocked by anti-TF and anti-PAR2 antibodies.(2) Factorâ…¦a alone,at high concentration of 10 nM,could induce IL-8 release in SW620 cells.(3) Factorâ…¡a showed slightly down-regulation on IL-8 expression,and could be attenuated with Hirudin, anti-PAR1 or anti-PAR2 antibodies.(4) Factorâ…¦a and PAR2-AP could induce IL-8 expression both at mRNA and protein levels,up-regulate TF mRNA expression and TF activity,meanwhile,down-regulate caspase-7 mRNA expression and p-p38 MAPK levels in SW620 cells.All the effects of factorâ…¦a were inhibited not only by anti-TF but also by anti-PAR2 antibodies.Conclusion:The TF-â…¦a and TF-â…¦a-â…©a complex,but notâ…¡a,can activate PAR2 on SW620 cells.Factorâ…¦a binds to TF on cell surface, forming a complex that can activate PAR2,and provoke IL-8 and TF expression,suppress caspase-7 expression,which are contributated to SW620 cell proliferation and migration.The p38 MAPK of the signal transduction pathway may negatively regulate the process.