CXCL8 and melanoma: They could not demonstrate any correlation of PPARγ expression with the different stages of melanoma disease, but evidenced an increased release of pro-tumorigenic cytokines (Interleukin 1β (IL1 β, Interleukin 6 (IL6)), chemokines (granulocyte-macrophage colony-stimulating factor (GM-CSF)), and angiogenic factors (angiopoietin-like 4 (ANGPTL4), Interleukin 8 (IL8)) by melanoma cells treated with the thiazolidinedione rosiglitazone.