HIF1A and lung cancer: Hypoxia-induced lung cancer stem cell-derived exosomes promote proliferation, migration, and angiogenesis of A549 cells, whereas aspirin attenuates this effect by reducing exosome secretion and altering exosome components (i.e., upregulating HIF-1α/COX-2 and downregulating exosomal miR-135b and miR-210) [29].