IL6 and obstructive sleep apnea syndrome: In addition, IH leads to significant increase in IL-6 expression in macrophages and promotes M1 macrophage polarization [21], which reveal the mechanisms by which OSA enhances inflammation and fibrosis in patients with fatty liver disease, while it has been shown that tumor-associated macrophages (TAMs) exhibit reductions in M1 macrophage markers in IH-exposed tumors [22].