MicroRNAs: As Critical Regulators of Tumor- Associated Macrophages

Int J Mol Sci. 2020 Sep 27;21(19):7117. doi: 10.3390/ijms21197117.

Abstract

Emerging shreds of evidence suggest that tumor-associated macrophages (TAMs) modulate various hallmarks of cancer during tumor progression. Tumor microenvironment (TME) prime TAMs to execute important roles in cancer development and progression, including angiogenesis, matrix metalloproteinases (MMPs) secretion, and extracellular matrix (ECM) disruption. MicroRNAs (miRNAs) are critical epigenetic regulators, which modulate various functions in diverse types of cells, including macrophages associated with TME. In this review article, we provide an update on miRNAs regulating differentiation, maturation, activation, polarization, and recruitment of macrophages in the TME. Furthermore, extracellular miRNAs are secreted from cancerous cells, which control macrophages phenotypic plasticity to support tumor growth. In return, TAMs also secrete various miRNAs that regulate tumor growth. Herein, we also describe the recent updates on the molecular connection between tumor cells and macrophages. A better understanding of the interaction between miRNAs and TAMs will provide new pharmacological targets to combat cancer.

Keywords: dendritic cells (DCs); interleukins (ILs); microRNA (miRNA); tumor microenvironment (TME); tumor-associated macrophages (TAMs); tumor-necrosis factor-α (TNF-α).

Publication types

  • Review

MeSH terms

  • Animals
  • Cell Differentiation / genetics
  • Cell Differentiation / immunology
  • Cell Polarity / genetics
  • Cell Polarity / immunology
  • Disease Progression
  • Gene Expression Regulation, Neoplastic / immunology
  • Humans
  • Macrophage Activation / genetics
  • Macrophage Activation / immunology
  • MicroRNAs / genetics
  • MicroRNAs / metabolism*
  • Neoplasms / genetics
  • Neoplasms / immunology*
  • Neoplasms / metabolism*
  • Tumor Microenvironment / immunology*
  • Tumor-Associated Macrophages / immunology*
  • Tumor-Associated Macrophages / metabolism*

Substances

  • MicroRNAs