In mouse neural progenitor cells GM-CSF treatment induces a PI3K–NF-κB signaling pathway that increases HIF-1α expression [38], and in a mouse melanoma model GM-CSF treatment induces macrophage secretion of vascular endothelial growth factor (VEGF) in a HIF-1α-dependent manner [39]. This evidence concerns the gene NFKB1 and melanoma.