Down-regulated TCF3 expression inhibits growth and migratory abilities of non-small cell lung cancer cells / 中国病理生理杂志

ABSTRACT

AIM:To investigate the effects of T-cell factor 3 (TCF3) expression on the growth and migratory abilities of the non-small cell lung cancer cells ( NSCLC) and the underlying mechanisms .METHODS: The non-small cell lung cancer cells A549 and H1299 were transfected with siTCF3 or negative control siRNA ( NCsiRNA) using Lipo-fectamine 2000.The expression of TCF3 at mRNA and protein levels was detected by real-time PCR and Western blot , re-spectively.The activity of TCF3 transcription was measured using luciferase reporter gene assay .The cell viability, colony formation ability, migratory ability and apoptotic rate were monitored by MTT assay , colony formation assay, Transwell method and flow cytometry with Annexin V-FITC/PI double staining , respectively .The protein expression levels of Wnt , c-Myc, matrix metalloproteinase (MMP)-9, MMP-13 and tissue inhibitor of metalloproteinase-1 (TIMP-1) were detected by Western blot.RESULTS:Compared with A549-NCsiRNA and H1299-NCsiRNA cells, the mRNA and protein levels of TCF3 were significantly inhibited in A549-siTCF3 and H1299-siTCF3 cells (P<0.01).The activity of TCF3 transcription and levels of c-Myc protein expression remarkably decreased as compared with NCsiRNA cells (P<0.05).The viability of A549-siTCF3 cells and H1299-siTCF3 cells cultured for 24 h, 48 h, 72 h and 96 h were notably lower than that of NCsi-RNA cells (P<0.05).The colony formation ability was significantly inhibited by siTCF 3 compared with NCsiRNA cells (P<0.01).The numbers of migratory A549-siTCF3 and H1299-siTCF3 cells were significantly lower than those of A549-NCsiRNA and H1299-NCsiRNA cells (P<0.05).The apoptotic rates of A549-siTCF3 cells and H1299-siTCF3 cells were notably higher than those of A549-NCsiRNA cells and H1299-NCsiRNA cells (P<0.01).Down-regulated TCF3 expres-sion inhibited the protein expression of Wnt , decreased the protein levels of MMP-9 and MMP-13 and enhanced the protein level of TCF3.CONCLUSION:siTCF3 suppresses the abilities of growth and migration , and induces apoptosis in A 549 cells and H1299 cells by down-regulating Wnt pathway and regulating expression of key MMP family genes .