RESUMO
Actin-binding proteins (ABPs) are important components of the F-actin cytoskeleton and affect the dynamics of F-actin by promoting the polymerization and depolymerization of actin. Numerous studies have shown that F-actin and actin-binding proteins are involved in all stages of carcinogenesis. Our analysis of esophageal carcinoma proteomic data showed that the actin-binding protein EHD2 (E p s l 5 homology domain-containing protein 2) is expressed at low levels in esophageal squamous cell carcinoma tissues and patients with lower EHD2 expression had poorer prognosis. Previous studies have revealed that EHD2 is involved in the regulation of glucose metabolism, autophagy and tumor cell migration. However, the role and mechanism of EHD2 in esophageal squamous cell carcinoma progression remain unclear. This study aimed to explore the effect of EHD2 on the proliferation of esophageal squamous cell carcinoma. Immunofluorescence and cell fractionation analysis showed that EHD2 was not only localized in the cell membrane and cytoplasm, but also in the nucleus. Colony formation, EdU labeling and flow cytometry were used to determine the effect of EHD2 on the proliferation of esophageal squamous cell carcinoma. The results showed that overexpression of EHD2 and EHD2-3×NLS (nuclear localization signal) inhibited proliferation, cell cycle G
RESUMO
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 .