Histamine-releasing factor (HRF), also termed translationally controlled tumor protein (TCTP) and fortilin, is a
highly conserved, multi-functional protein. This protein within a cell plays a critical role in the fundamental processes of
cell-cycle progression, proliferation, survival, and malignant transformation. The same protein, despite the lack of signal
sequence, is secreted through a nonclassical secretory pathway. The secreted protein usually termed HRF can activate
IgE-primed basophils and mast cells, and works as a B cell growth factor and a chemoattractant for eosinophils. This
structurally well-characterized protein interacts with many proteins to perform its intracellular and extracellular functions.
This review summarizes recent studies of HRF/TCTP-interacting proteins as a major driving force to decipher its