MiR-106b-5p Promotes Proliferation and Inhibits Apoptosis by Regulating BTG3 in Non-Small Cell Lung Cancer

Cell Physiol Biochem. 2017;44(4):1545-1558. doi: 10.1159/000485650. Epub 2017 Dec 4.

Abstract

Background/aims: MicroRNAs have been validated to play a crucial role in tumorigenesis of non-small cell lung cancer (NSCLC). Although miR-106b-5p has been reported to play a vital role in various malignancies the physiological function of miR-106b-5p in NSCLC still remain unknown. In this study, we investigated the role of miR-106b-5p in NSCLC.

Methods: Quantitative real-time polymerase chain reaction was conducted to estimate the expression of miR-106b-5p and BTG3 in both NSCLC tissues and cell lines. The effects of miR-106b-5p on proliferation were determined in vitro using CCK-8 proliferation assays, 5-ethynyl-2'-deoxyuridine (EdU) incorporation, colony formation assays and cell-cycle assays and the in vivo effects were evaluated by a mouse tumorigenicity model. Cell apoptosis and cell cycle was investigated by flow cytometric analysis in vitro. The molecular mechanism underlying the relevance between miR-106b-5p and BTG3 was confirmed by luciferase assay and western blot.

Results: In current study, we found a relatively higher miR-106b-5p and lower BTG3 expression in NSCLC specimens and cell lines. BTG3 was verified as a direct target of miR-106b-5p by luciferase assay. In vitro, over-expression of miR-106b-5p promoted proliferation and inhibited apoptosis by down-regulating BTG3 expression. In vivo, miR-106b-5p promoted xenograft tumor formation.

Conclusion: Our findings revealed for the first time that miR-106b-5p plays a tumorigenesis role in NSCLC progression by down-regulating BTG3 expression, which may lead to a novel insight to the potential biomarker and novel therapeutic strategies for NSCLC patients.

Keywords: Apoptosis; BTG3; Microrna-106b-5p; Non-small-cell lung cancer; Proliferation.

MeSH terms

  • 3' Untranslated Regions
  • Aged
  • Animals
  • Antagomirs / metabolism
  • Apoptosis
  • Base Sequence
  • Carcinoma, Non-Small-Cell Lung / genetics
  • Carcinoma, Non-Small-Cell Lung / pathology*
  • Cell Cycle Proteins
  • Cell Line, Tumor
  • Cell Proliferation
  • Female
  • Humans
  • Lung Neoplasms / genetics
  • Lung Neoplasms / pathology*
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Mice, Nude
  • MicroRNAs / antagonists & inhibitors
  • MicroRNAs / genetics
  • MicroRNAs / metabolism*
  • Middle Aged
  • Proteins / antagonists & inhibitors
  • Proteins / genetics
  • Proteins / metabolism*
  • RNA Interference
  • RNA, Small Interfering / metabolism
  • Sequence Alignment
  • Transplantation, Heterologous

Substances

  • 3' Untranslated Regions
  • Antagomirs
  • BTG3 protein, human
  • Cell Cycle Proteins
  • MIRN106 microRNA, human
  • MicroRNAs
  • Proteins
  • RNA, Small Interfering