S100 calcium-binding protein P (S100P)

S100 calcium-binding protein P is a small (11 kDa) member of the S100 protein family characterized by two EF-hand motifs that bind calcium ions, as well as zinc and magnesium. S100P is expressed in various tissues including placenta, stomach, bladder, and bone marrow and is upregulated in several cancers. It regulates key processes such as cell proliferation, differentiation, survival, migration, and invasion by interacting with proteins like ezrin and RAGE. S100P acts both within cells and as an extracellular signaling molecule, modulating cytoskeletal dynamics, extracellular matrix remodeling, and gene transcription. In oncology, overexpression of S100P correlates with tumor aggressiveness, metastasis, and resistance to chemotherapy, making it a candidate prognostic biomarker and potential therapeutic target, especially in breast and prostate cancer.

Other names

S100PProtein S100-PS100EMIG9Migration-inducing gene 9 proteinProtein S100-ES100 calcium-binding protein P

Drugs such as cromolyn and pentamidine inhibit the interaction between S100P and the receptor for advanced glycation end products (RAGE), which mediates cell signaling important for tumor growth and migration.