ABSTRACT
<p><b>OBJECTIVE</b>To investigate the effect of epithelial-mesenchymal transition (EMT) on the expression of microRNAs (miRNAs) in lung cancer A549 cells.</p><p><b>METHODS</b>Transforming growth factor beta-1 (TGF-beta 1) in different concentrations was used to induce EMT in lung cancer A549 cells. The morphological changes were observed under phase-contrast microscope. The changes of EMT-related proteins were analyzed by Western blot. The changes of miRNAs expression after EMT were detected by microRNA (miRNA) array. Real time quantitative RT-PCR was applied to verify the reliability of miRNA array results.</p><p><b>RESULTS</b>The lung cancer A549 cells became elongated and the cell-cell junction became loose after EMT. The epithelial protein marker E-cadherin was down-regulated and the mesenchymal protein markers vimentin and fibronectin up-regulated. There were 51 miRNAs showing statistically significant changes of expression more than double (P<0.05) after EMT. Among them 18 were up-regulated and 33 down-regulated. Of them, mir-33a was down-regulated by 92.8% and mir-193a-3p by 86.5%. Real time quantitative RT-PCR showed that mir-33a was down-regulated by 73.1% and mir-193a-3p by 56.6%.</p><p><b>CONCLUSION</b>Epithelial-mesenchymal transition has effects on the expression of miRNAs, and miRNAs may regulate the invasion and metastasis of lung cancer cells via EMT.</p>
Subject(s)
Humans , Adenocarcinoma , Genetics , Metabolism , Pathology , Cadherins , Metabolism , Cell Line, Tumor , Epithelial-Mesenchymal Transition , Fibronectins , Metabolism , Gene Expression Profiling , Lung Neoplasms , Genetics , Metabolism , Pathology , MicroRNAs , Genetics , Metabolism , Transforming Growth Factor beta1 , Pharmacology , Vimentin , MetabolismABSTRACT
<p><b>OBJECTIVE</b>To investigate the mutations in exon 19 of epidermal growth factor receptor (EGFR) gene in non-small cell lung cancer from Chinese patients.</p><p><b>METHODS</b>Genomic DNA was extracted from 72 lung cancer tissues. Then the exon 19 of EGFR gene was amplified by nested PCR and sequenced.</p><p><b>RESULTS</b>In 13 tumor tissues, multi-nucleotide in-frame deletion mutations at the exon 19 of EGFR gene, had been detected. There were 4 mutation types. The mutation rate was 18.1%. The mutations were all heterozygous. There was association of the exon 19 mutation of EGFR gene with adenocarcinoma, female patients and non-smokers.</p><p><b>CONCLUSION</b>There were multi-nucleotide in-frame deletion mutations in exon 19 of EGFR gene. Mutations of the exon 19 of EGFR gene were higher in female, non-smoking and adenocarcinoma patients.</p>