Silencing of lncRNA KLF3-AS1 represses cell growth in osteosarcoma via miR-338-3p/MEF2C axis

J Clin Lab Anal. 2022 Nov;36(11):e24698. doi: 10.1002/jcla.24698. Epub 2022 Oct 17.

Abstract

Background: Osteosarcoma (OS) is a highly recurrent malignancy occurring among adolescents. The goal of this research was to scrutinize the role and action mechanism of KLF3-AS1 in OS.

Methods: Western blotting and quantitative reverse transcription real-time PCR were conducted to ascertain the mRNA expressions of miR-338-3p, KLF3-AS1, and MEF2C in OS cell lines and tissue samples. Colony formation and CCK-8 experiments were done to evaluate the proliferative capacity of the cells. Western blotting was also executed to measure the relative expressions of the proteins Bcl-2 and Bax. RNA immunoprecipitation and dual luciferase reporter experiments were carried out to validate the target relationships among MEF2C, KLF3-AS1, and miR-338-3p. Mouse xenograft models were created to assess the influences of KLF3-AS1 on the growth of tumors in vivo.

Results: Elevated levels of KLF3-AS1 and MEF2C and reduced amounts of miR-338-3p were identified in OS. KLF3-AS1 targeted miR-338-3p, and miR-338-3p further targeted MEF2C. Silencing KLF3-AS1 induced apoptosis and attenuated proliferation in vitro and repressed the tumor growth in vivo. Inhibiting miR-338-3p inverted the cancer-suppressing effects of KLF3-AS1 silencing. Meanwhile, loss of MEF2C partially eliminated the effects brought about by miR-338-3p downregulation, namely the stimulation of cell growth and suppression of apoptosis.

Conclusions: Silencing of KLF3-AS1 could repress the growth of cells and induce apoptosis by regulating miR-338-3p/MEF2C in OS. This suggests that the regulatory axis KLF3-AS1/miR-338-3p/MEF2C is a prospective target for OS treatment.

Keywords: KLF3-AS1; MEF2C; apoptosis; miR-338-3p; osteosarcoma; proliferation.

MeSH terms

  • Animals
  • Bone Neoplasms* / genetics
  • Bone Neoplasms* / pathology
  • Cell Line, Tumor
  • Cell Proliferation / genetics
  • Humans
  • Kruppel-Like Transcription Factors / genetics
  • MEF2 Transcription Factors* / genetics
  • Mice
  • MicroRNAs* / genetics
  • MicroRNAs* / metabolism
  • Neoplasm Recurrence, Local
  • Osteosarcoma* / genetics
  • Osteosarcoma* / pathology
  • RNA, Long Noncoding* / genetics
  • RNA, Long Noncoding* / metabolism

Substances

  • KLF3 protein, human
  • Kruppel-Like Transcription Factors
  • MEF2 Transcription Factors
  • MEF2C protein, human
  • MicroRNAs
  • MIRN338 microRNA, human
  • RNA, Long Noncoding