Raf kinase inhibitor protein (RKIP),also termed phosphatidylethanolamine binding protein PEBP1,was initially identified as a potent inhibitor of Raf-1/MEK/ERK,NF-kB,and G-protein-coupled receptor signaling pathways. Later RKIP has been further identified as a metastasis suppressor and its loss of expression has been reported in various cancers. Its expression has been proposed as a prognostic marker for patients diagnosed with the above cancers.