CSF2 and melanoma: In October 2015, a herpes simplex virus 1 (HSV-1) expressing granulocyte-macrophage colony-stimulating factor (GM-CSF) named T-VEC (talimogene laherparepvec, Amgen, Inc., Thousand Oaks, CA, USA) became the first OV approved by the US Food and Drug Administration (FDA) for the treatment of advanced melanoma [7].