S100P is a member of the S100 family of proteins containing 2 EF-hand calcium-binding motifs. S100 proteins are localized in the cytoplasm and/or nucleus of a wide range of cells, and involved in the regulation of a number of cellular processes such as cell cycle progression and differentiation. S100 genes include at least 13 members which are located as a cluster on chromosome 1q21; however, this gene is located at 4p16. This protein, in addition to binding Ca2 , also binds Zn2 and Mg2 . This protein may play a role in the etiology of prostate cancer.
S100P showed a pattern of expression similar to that of S100PBP in both healthy pancreas and pancreatic cancer. Immunohistochemical analysis showed that S100P expression correlated significantly with increasing grade of pancreatic intraepithelial neoplasia.