Regulation of Ras homolog family member G by microRNA-124 regulates proliferation and migration of human retinal pigment epithelial cells

Sci Rep. 2020 Sep 22;10(1):15420. doi: 10.1038/s41598-020-72360-5.

Abstract

Uncontrolled retinal pigment epithelial (RPE) cell proliferation/migration contribute to the pathological tractional membrane development in proliferative vitreoretinopathy. Recent studies reported that microRNA (miR)-124 controls various cellular functions via the direct targeting of small Ras homolog family member G (RHOG). Therefore, we investigated the role of the neuron-specific miR-124 and RHOG in RPE cell proliferation/migration. Alterations in miR-124 and RhoG expression, as per cell confluence were evaluated through quantitative real-time PCR and western blotting, respectively. After transfection with miR-124, we quantified RPE cell viability and migration and observed cell polarization and lamellipodia protrusions. We evaluated the expression of RHOG/RAC1 pathway molecules in miR-124-transfected RPE cells. Endogenous miR-124 expression increased proportionally to RPE cell density, but decreased after 100% confluence. Overexpression of miR-124 decreased cell viability and migration, BrdU incorporation, and Ki-67 expression. Inhibition of endogenous miR-124 expression promoted RPE cell migration. Transfection with miR-124 reduced cell polarization, lamellipodia protrusion, and RHOG mRNA 3' untranslated region luciferase activity. Like miR-124 overexpression, RhoG knockdown decreased RPE cell viability, wound healing, and migration, and altered the expression of cell cycle regulators. These results suggest that miR-124 could be a therapeutic target to alleviate fibrovascular proliferation in retinal diseases by regulating RPE proliferation/migration via RHOG.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Movement / genetics*
  • Cell Proliferation / genetics*
  • Cells, Cultured
  • Down-Regulation / genetics
  • Epithelial Cells / pathology*
  • Humans
  • MicroRNAs / genetics*
  • Neurons / pathology
  • RNA, Messenger / genetics
  • Retinal Pigment Epithelium / pathology*
  • Retinal Pigments / genetics*
  • Vitreoretinopathy, Proliferative / genetics
  • Vitreoretinopathy, Proliferative / pathology
  • rho GTP-Binding Proteins / genetics*

Substances

  • MIRN124 microRNA, human
  • MicroRNAs
  • RNA, Messenger
  • Retinal Pigments
  • RHOG protein, human
  • rho GTP-Binding Proteins