LBX2-AS1/miR-219a-2-3p/FUS/LBX2 positive feedback loop contributes to the proliferation of gastric cancer

Gastric Cancer. 2020 May;23(3):449-463. doi: 10.1007/s10120-019-01019-6. Epub 2019 Oct 31.

Abstract

Background: Long non-coding RNAs (lncRNAs) are increasingly investigated in numerous carcinomas containing gastric cancer (GC). The aim of our research is to inquire about the expression profile and role of LBX2-AS1 in GC.

Methods: The expressions of LBX2-AS1, miR-219a-2-3p, FUS and LBX2 were measured by qRT-PCR. Western blot evaluated FUS and LBX2 protein levels. Cell proliferation and apoptosis were, respectively, evaluated by CCK-8, colony formation, EdU, flow cytometry and TUNEL assays. FISH and subcellular fractionation assays examined the position of LBX2-AS1. The binding between genes were certified by RIP, RNA pull-down, ChIP and luciferase reporter assays. Pearson correlation analysis analyzed the association of genes. Kaplan-Meier method detected the relationship of LBX2-AS1 expression with overall survival.

Results: The up-regulation of LBX2-AS1 in GC tissues and cells was verified. Function assays proved that LBX2-AS1 down-regulation restricted the proliferation ability. Then, we unveiled the LBX2-AS1/miR-219a-2-3p/FUS axis. Additionally, LBX2-AS1 positively regulated LBX2 mRNA stability via FUS. LBX2 transcriptionally modulated LBX2-AS1. In the end, rescue and in vivo experiments validated the whole regulatory mechanism.

Conclusion: LBX2-AS1/miR-219a-2-3p/FUS/LBX2 positive feedback loop mainly affected the proliferation and apoptosis abilities of GC cells, offering novel therapeutic targets for the treatment of patients with GC.

Keywords: Fused in sarcoma (FUS); Gastric cancer (GC); LBX2 antisense RNA 1 (LBX2-AS1); Ladybird homeobox 2 (LBX2); miR-219a-2-3p.

MeSH terms

  • Animals
  • Apoptosis
  • Biomarkers, Tumor / genetics
  • Biomarkers, Tumor / metabolism*
  • Cell Proliferation
  • Feedback, Physiological
  • Gene Expression Regulation, Neoplastic*
  • Homeodomain Proteins / genetics
  • Homeodomain Proteins / metabolism*
  • Humans
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Mice, Nude
  • MicroRNAs / genetics*
  • Prognosis
  • RNA, Antisense / genetics
  • RNA, Long Noncoding / genetics*
  • RNA-Binding Protein FUS / genetics
  • RNA-Binding Protein FUS / metabolism*
  • Stomach Neoplasms / genetics
  • Stomach Neoplasms / metabolism
  • Stomach Neoplasms / pathology*
  • Survival Rate
  • Tumor Cells, Cultured
  • Xenograft Model Antitumor Assays

Substances

  • Biomarkers, Tumor
  • FUS protein, human
  • Homeodomain Proteins
  • LBX2 protein, human
  • MIRN219 microRNA, human
  • MicroRNAs
  • RNA, Antisense
  • RNA, Long Noncoding
  • RNA-Binding Protein FUS