miR-106b Promotes Metastasis of Early Gastric Cancer by Targeting ALEX1 in Vitro and in Vivo

Cell Physiol Biochem. 2019;52(3):606-616. doi: 10.33594/000000043.

Abstract

Background/aims: Aberrant expression of miR-106b is a specific symptom of many solid carcinomas. Overexpression of miR-106b has been observed in gastric cancer. The effect of miR-106b on gastric cancer has been investigated in different cell culture models. However, the effect of miR-106b on metastasis of early gastric cancer (EGC) remains unknown.

Methods: In the study, qRT-PCR, FISH, western blot, luciferase reporter assay, migration and invasion assays, flow cytometry and TUNEL staining were used to investigate the effect of miR-106b on metastasis of EGC.

Results: To explore the function of miR-106b in EGC, we investigated the downstream signaling of miR-106b and found that ALEX1 was a direct target of miR-106 in gastric cancer cells. Up-regulation of ALEX1 effectively rescued the cell apoptosis induced by miR-106b inhibitor and promoted the expression levels of phosphorylation of JAK1 and STAT3. Moreover, overexpression of JAK1 reduced the cell apoptosis induced by miR-106b inhibitor and decreased the expression levels of the apoptotic proteins in gastric cancer cells. Furthermore, down-regulation of miR-106b promoted apoptosis of gastric cancer cells via inhibiting JAK1/STAT3 signaling pathway in vitro and in vivo. In addition, GLPG0643, a JAK1 inhibitor, enhanced the inhibitory effect of miR-106b inhibitor on gastric cancer growth in vivo.

Conclusion: These findings provided a potential therapeutic manner for the treatment of metastasis of EGC in clinic.

Keywords: ALEX1; EGC; GLPG0643; JAK1/STAT3 signaling pathway; Metastasis; miR-106b.

MeSH terms

  • Animals
  • Antagomirs / metabolism
  • Apoptosis
  • Armadillo Domain Proteins / chemistry
  • Armadillo Domain Proteins / genetics
  • Armadillo Domain Proteins / metabolism*
  • Cell Line, Tumor
  • Cell Movement / drug effects
  • Cell Proliferation / drug effects
  • Down-Regulation
  • Humans
  • Janus Kinase 1 / antagonists & inhibitors
  • Janus Kinase 1 / metabolism
  • Mice
  • Mice, Inbred BALB C
  • Mice, Nude
  • MicroRNAs / antagonists & inhibitors
  • MicroRNAs / genetics
  • MicroRNAs / metabolism*
  • Neoplasm Metastasis
  • Oncogene Proteins / chemistry
  • Oncogene Proteins / genetics
  • Oncogene Proteins / metabolism*
  • Protein Kinase Inhibitors / pharmacology
  • STAT3 Transcription Factor / metabolism
  • Signal Transduction / drug effects
  • Stomach Neoplasms / metabolism
  • Stomach Neoplasms / pathology*
  • Up-Regulation

Substances

  • ARMCX1 protein, human
  • Antagomirs
  • Armadillo Domain Proteins
  • MIRN106 microRNA, human
  • MicroRNAs
  • Oncogene Proteins
  • Protein Kinase Inhibitors
  • STAT3 Transcription Factor
  • Janus Kinase 1