CXCL8 and melanoma: Studies on melanoma cell lines have demonstrated that stimulation by catecholamines activates p42/p44 and p38 mitogen-activated protein kinases (MAPKs) pathways, which are responsible for growth, survival, and metastatic cancer cell responses, along with increased production of matrix metalloproteinase (MMP)-2 and 9, IL-6, IL-8, and VEGF [17,38,58].