Intermittent hypoxia exacerbates tumor progression in a mouse model of lung cancer

Sci Rep. 2020 Feb 5;10(1):1854. doi: 10.1038/s41598-020-58906-7.

Abstract

The purpose of this study was to evaluate whether obstructive sleep apnea (OSA)-related chronic intermittent hypoxia (CIH) influences lung cancer progression and to elucidate the associated mechanisms in a mouse model of lung cancer. C57/BL6 mice in a CIH group were exposed to intermittent hypoxia for two weeks after tumor induction and compared with control mice (room air). Hypoxia inducible factor 1α (HIF-1α), vascular endothelial growth factor (VEGF) and metastasis-related matrix metalloproteinases (MMP) were measured. The expression levels of several hypoxia-related pathway proteins including HIF-1α, Wnt/ß-catenin, the nuclear factor erythroid 2-related factor 2 (Nrf2) and mammalian target of rapamycin-ERK were measured by western blot. The number (P < 0.01) and volume (P < 0.05) of tumors were increased in the CIH group. The activity of MMP-2 was enhanced after CIH treatment. The level of VEGF was increased significantly in the CIH group (p < 0.05). ß-catenin and Nrf2 were translocated to the nucleus and the levels of downstream effectors of Wnt/ß-catenin signaling increased after IH exposure. CIH enhanced proliferative and migratory properties of tumors in a mouse model of lung cancer. ß-catenin and Nrf2 appeared to be crucial mediators of tumor growth.

MeSH terms

  • Animals
  • Cell Proliferation / physiology
  • Disease Models, Animal
  • Disease Progression
  • Hypoxia / metabolism
  • Hypoxia / pathology*
  • Lung Neoplasms / metabolism
  • Lung Neoplasms / pathology*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • NF-E2-Related Factor 2 / metabolism
  • Signal Transduction / physiology
  • Sleep Apnea, Obstructive / metabolism
  • Sleep Apnea, Obstructive / pathology
  • Vascular Endothelial Growth Factor A / metabolism
  • beta Catenin / metabolism

Substances

  • NF-E2-Related Factor 2
  • Vascular Endothelial Growth Factor A
  • beta Catenin