RESUMO
BACKGROUND: Epithelial-mesenchymal transition (EMT) is believed to be the critical process in malignant tumor invasion and metastases, and has a great influence on improving the survival rate in non-small-cell lung cancer (NSCLC) patients. Recent studies suggested that eukaryotic initiation factor 5A-2 (eIF5A-2) might serve as an adverse prognostic marker of survival. We detected eIF5A-2 in NSCLC A549 cells, and found that the invasive capability correlates with the eIF5A-2 expression. METHODS: Transforming growth factor (TGF)-ß1 was used to induce EMT in A549 cells. Western blotting, immunofluorescence, wound healing assay, and transwell-matrigel invasion chambers were used to identify phenotype changes. Western blotting was also used to observe changes of the expression of eIF5A-2. We down-regulated the eIF5A-2 expression using an eIF5A-2 siRNA and identified the phenotype changes by western blotting and immunofluorescence. We tested the change of migration and invasion capabilities of A549 cells by the wound healing assay and transwell-matrigel invasion chambers. RESULTS: After stimulating with TGF-ß1, almost all A549 cells changed to the mesenchymal phenotype and acquired more migration and invasion capabilities. These cells also had higher eIF5A-2 protein expression. Down-regulation of eIF5A-2 expression with eIF5A-2 siRNA transfection could change the cells from mesenchymal to epithelial phenotype and decrease tumor cell migration and invasive capabilities significantly. CONCLUSIONS: The expression of eIF5A-2 was up-regulated following EMT phenotype changes in A549 cells, which correlated with enhanced tumor invasion and metastatic capabilities. Furthermore, in the A549 cell line, the process of EMT phenotype change could be reversed by eIF5A-2 siRNA, with a consequent weakening of both invasive and metastatic capabilities.
Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/fisiopatologia , Regulação para Baixo/genética , Transição Epitelial-Mesenquimal/genética , Técnicas de Silenciamento de Genes/métodos , Fatores de Iniciação de Peptídeos/genética , Proteínas de Ligação a RNA/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Sobrevivência Celular/genética , Humanos , Fator de Iniciação de Tradução Eucariótico 5ARESUMO
<p><b>OBJECTIVE</b>To compare the long-term influence of vertebral fixation through or across the affected vertebra on vertebral morphology.</p><p><b>METHODS</b>Clinical data of 48 patients with simple thoracic and lumbar spinal fractures who were admitted between Jan. 2008 and Dec. 2010 were analyzed retrospectively. Among them 36 cases (28 males and 8 females) were fixed through the injured vertebra (group A) and 12 cases (8 males and 4 females) were fixed across the injured vertebra (group B). All patients were followed up for 6-36 months (mean 11.5 months). The vertebral body height, endplate angle and neurofunction were compared between the two groups before surgery, a week after surgery and at the end of the follow-up period.</p><p><b>RESULTS</b>There was no statistically significant difference in vertebral body height,endplate angle and neurofunction before operation between group A and B (P > 0.05). Vertebral body height and endplate angle improved in both groups a week after operation and at the end of the follow-up period as compared with those before operation (P < 0.05), and the efficacy in group B was significantly better than that in group A (P < 0.05). There was no significant difference in neurofunction between the two groups (P > 0.05).</p><p><b>CONCLUSION</b>The fixation method through the injured vertebra had a better reduction effect, more stable fixation, and a better long-term effect on vertebral morphology than that across the injured vertebra in the treatment of thoracolumbar vertebral fractures.</p>
