Expression of microRNA-96 and its potential functions by targeting FOXO3 in non-small cell lung cancer

Tumour Biol. 2015 Feb;36(2):685-92. doi: 10.1007/s13277-014-2698-y. Epub 2014 Oct 7.

Abstract

MicroRNAs are implicated in the regulation of various cellular processes, including proliferation, differentiation, cell death, and cell mobility, and can function either as oncogenes or tumor suppressors in tumor progression. The effects of the expression of miR-96 in non-small cell lung cancer (NSCLC) remain unclear. In our study, qRT-PCR (quantitative reverse transcription PCR) was performed to identify the miR-96 expression level in 68 paired NSCLC and adjacent normal lung tissues. Trans-well, cell counting kit-8, and apoptosis assays were used to evaluate the effects of miR-96 expression on cell invasion, proliferation, and apoptosis. Dual-luciferase reporter assay and Western blotting were used to verify whether FOXO3 was a potential major target gene of miR-96. Finally, the effect of FOXO3 on miR-96-induced cell survival was determined by transfection of the genes expressing FOXO3 lacking 3'UTR and miR-96. The expression level of miR-96 in NSCLC tissues was higher than that in adjacent normal lung tissues, and this increased expression was significantly associated with lymph node metastasis. In contrast to the cells in the blank and negative control groups, the number of cells migrating through the matrigel was significantly lower and the incidence of apoptosis was significantly higher in cells transfected with a miR-96 inhibitor. Western blotting and dual-luciferase reporter assays demonstrated that miR-96 can bind to the putative seed region in FOXO3 mRNA 3'UTR, and can significantly lower the expression of FOXO3. The introduction of FOXO3 cDNA without 3'UTR restored miR-96 induced cell apoptosis and invasion. MiR-96 is up-regulated in NSCLC tissues. Downregulation of miR-96 inhibits invasion and promotes apoptosis in NSCLC cells A549 and SPC-A-1 by targeting FOXO3. Therefore, our study improves our understanding of the mechanisms underlying NSCLC pathogenesis and may promote the development of novel targeted therapies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoptosis / genetics
  • Biomarkers, Tumor / biosynthesis*
  • Biomarkers, Tumor / genetics
  • Carcinoma, Non-Small-Cell Lung / genetics*
  • Carcinoma, Non-Small-Cell Lung / pathology
  • Cell Line, Tumor
  • Cell Proliferation / genetics*
  • Forkhead Box Protein O3
  • Forkhead Transcription Factors / biosynthesis*
  • Forkhead Transcription Factors / genetics
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Lymphatic Metastasis / pathology
  • MicroRNAs / biosynthesis*
  • MicroRNAs / genetics
  • Neoplasm Invasiveness / genetics

Substances

  • Biomarkers, Tumor
  • FOXO3 protein, human
  • Forkhead Box Protein O3
  • Forkhead Transcription Factors
  • MIRN96 microRNA, human
  • MicroRNAs