Abstract： Phospholipid scramblase 1(PLSCR1)is a calcium-binding,multiply palmitoylated typeⅡ endofacial plasma membrane protein,while unpalmitoylated PLSCR 1 protein can import into the nucleus,where it binds to genomic DNA.Although the original work showed that PLSCR1 contributes to the transbilayer movement of phospholipids,the following studies revealed that PLSCR1 expression can be induced by some cytokines such as interferon,epidermal growth factor,and also by leukemic cell differentiationinducing agents such as all-trans retinoic acid(ATRA)and phorbol 12-myristate 13-acetate(PMA).PLSCR1 was also shown to interact with several protein kinases including c-Ab1,c-Src,protein kinase Cδ as well as some other proteins such as onzln,suggesting the roles of PLSCR1 in cell signaling.Indeed,the current evidence proposes that PLSCR1 contributes to cell proliferation,differentiation,apoptosis,and plays roles in the pathogenesis of cancers,especially leukemia.