HIF1A and obstructive sleep apnea syndrome: Both in OSA patients as well as in vitro and animal models [4,5,6], hypoxia-inducible factor (HIF1α) overexpression secondary to intermittent hypoxia (IH) compromises the immunosurveillance system by altering several immune subsets, which favors the development of a tumor-promoting environment [5,6,7].