TMTP1 Bands Its Receptor XPNPEP2 And Selectively Induces The Apoptosis Of Cancer Cell

Objective:To capture and verify the receptor of a tumor homing peptide TMTP1 is helpfulto know about the mechanism of tumor homing effect.The receptor may be a potentialtherapeutic target.Methods:The motheds of pull-down (affinity chromatography)method were used toseparate the membrane protein molecules interacting with TMTP1 and indetify the somekind(s)of protein(s)using the Spectral analysis from the mixture of proteins.The validationof receptor including following aspect:the subcellular localization,the distribution,thebinding and the functional testing.We also used MTT assay,FCM,western-blot to verifythe inhibiton on tumor cell proliferation induced by TMTP1 and to investigate themechanism.Results:XPNPEP2 and Hsp27 are candidate receptor captured by pull-down.XPNPEP2expresses in the cellular surface,it can bind TMTP1 strongly and shows a good results inthe functional test.Its distribution also coincides with the rules which we screens theTMTP1 by phage display.Hsp27 is a intracellular binding protein of TMTP1,it negativelyregulate the apoptosis induced by TMTP1 through the PI3K/Hsp27 pathway.Conclusions:XPNPEP2 is a cellular surface receptor of TMTP1 and mediate theendocytosis of TMTP1.Hsp27 is a intracellular binding protein of TMTP 1,it plays a keyrole in the apoptosis induced by TMTP 1.