Gold‑manganese oxide nanocomposite suppresses hypoxia and augments pro-inflammatory cytokines in tumor associated macrophages

Int Immunopharmacol. 2018 Apr:57:157-164. doi: 10.1016/j.intimp.2018.02.021. Epub 2018 Feb 28.

Abstract

The tumor microenvironment, essentially hypoxic, is sustained by the hypoxia inducing factor (HIF), released from the pro-tumorigenic tumor associated macrophages (TAMs), functionally identical to the M2 phenotype macrophages. Stability of HIF mainly depends on molecular oxygen and an iron-dependent enzyme prolyl hydroxylase, while its activity may be inhibited by high levels of reactive oxygen species and nitric oxide. The present work showcases a novel approach utilizing the anti-tumorigenic potential of a gold-manganese oxide nanocomposite material in the tumor microenvironment that affects tumor hypoxia, exploring the possibility of restoring the immunoregulatory nature of TAMs from their pro-tumorigenic state. Along with the biochemical markers, ELISA and FACS analyses have also confirmed the potential of these nanoparticles in reverting back the M2 phenotype of TAMs to their classically activated M1 phenotype.

Keywords: Hypoxia; In vitro murine model; M1 and M2 macrophages; Metal nanocomposite; Pro and anti-tumorigenic cytokines.

MeSH terms

  • Animals
  • Cell Differentiation / drug effects
  • Cells, Cultured
  • Cytokines / metabolism
  • Fibrosarcoma / immunology
  • Fibrosarcoma / therapy*
  • Gold / chemistry
  • Gold / therapeutic use*
  • Hypoxia / immunology
  • Hypoxia / therapy*
  • Inflammation Mediators / metabolism
  • Iron / metabolism
  • Macrophages / physiology*
  • Male
  • Manganese Compounds / chemistry
  • Manganese Compounds / therapeutic use*
  • Mice
  • Nanocomposites / chemistry
  • Nitric Oxide / metabolism
  • Oxidation-Reduction
  • Oxides / chemistry
  • Oxides / therapeutic use*
  • Prolyl Hydroxylases / metabolism
  • Th1 Cells / immunology
  • Th2 Cells / immunology
  • Tumor Microenvironment

Substances

  • Cytokines
  • Inflammation Mediators
  • Manganese Compounds
  • Oxides
  • Nitric Oxide
  • manganese oxide
  • Gold
  • Iron
  • Prolyl Hydroxylases