Involved in calcium binding and microtubule stabilization. Interacts with STEAP3. Found in several healthy and tumoral cells including erythrocytes, hepatocytes, macrophages, platelets, keratinocytes, erythroleukemia cells, gliomas, melanomas, hepatoblastomas, and lymphomas. It cannot be detected in kidney and renal cell carcinoma (RCC). Expressed in placenta and prostate. Down-regulated in response to enterovirus 71 (EV71) infection. Belongs to the TCTP family.