: Gene, Promoter, Regulation of Expression, mRNA Stability, Regulation of Activity in the Intercellular Space.

is one of the most important chemokines, part of a group of chemotactic cytokines involved in the development of many inflammatory diseases. It activates CXCR2 and, at high levels, CXCR1. The expression of is elevated in inflammatory reactions and also has important functions in physiology, including the induction of angiogenesis and recruitment of neutrophils. Due to a lack of reviews that precisely describe the regulation of expression and function, in this paper, we present the mechanisms of expression regulation with a special focus on cancer. We concentrate on the regulation of expression through the regulation of transcription and mRNA stability, including the involvement of NF-κB, p53, the effect of miRNAs and cytokines such as IFN-γ, IL-1β, IL-17, TGF-β and TNF-α. We also describe the mechanisms regulating activity in the extracellular space, including proteolytic processing, dimerization and the influence of the ACKR1/DARC receptor on localization. Finally, we explain the role of in cancer and possible therapeutic approaches directed against this chemokine.