Activation of Notch1 Signaling Inhibits Proliferation of Human Colon Carcinoma Cells via Down-regulation of Wnt / 医学研究杂志

ABSTRACT

Objective To construct the recombinant retroviruses vector PCLNRX-ICN and to explore over-activation Notch1 on the growth of human colon carcinoma cells HT-29.MethodsICN(intracellular domain of Noctch1) genes were inserted into retrovirus expression vector pCLNRX.The expression vector pCLNRX-ICN and packaging vector pCL-10A1 were co-transfected into 293 package cells.The recombinant retroviruses were used to infect HT-29 cells.After being infected,proliferation of HT-29 cells was observed by MTT assay.The expression of c-Myc and ?-catenin detected by RT-PCR and Western Blot.ResultsRecombinant retrovirus vector pCLNRX-ICN was successfully constructed.Overactivation of Notch1 by over-expressing exogenous ICN significantly inhibited the growth of HT-29 cells,and down-regulated ?-catenin,a key regulator of Wnt signaling,in protein level but not in mRNA levels.However,the mRNA or protein levels of c-Myc were not affected by overactivation of Notch1.ConclusionOver-activated Notch1 signaling could inhibit the growth of HT-29 cells partly through down-regulation of Wnt signaling independent of c-Myc inhibition.