Growth regulated oncogene- alpha belongs to the family of chemotyctic cytokines called chemokines. It is identical with MGSA (melanoma growth stimulatory activity) and the new designation is CXCL1. This factor is known mainly because of its chemotactic activity. GRO expression is inducible by serum or PDGF and/or by a variety of inflammatory mediators, such as IL-1 and TNF, in monocytes, fibroblasts, melanocytes and epithelial cells. In certain tumor cell lines, GRO is expressed constitutively. Similar to other alpha chemokines, the three GRO proteins are potent neutrophil attractants and activators. In addition, these chemokines are also active toward basophils. All three GROs can bind with high affinity to the IL-8 receptor type B.