Abstract: FLIP is a protein containing death domain. Human beings have three subtypes of c-FLIP_L, c-FLIP_S and c-FLIP_R, which can inhibit the apoptosis of a variety of tumor cells. C-FLIP_L plays a dual role in the apoptotic signal. The expression level of FLIP not only decides the opening and closing of the apoptosis pathway but also achieve the conversion of cells in the apoptotic signaling and proliferative signaling pathway. The regulation of FLIP’s expression is a multi-layered, involving multiple signaling pathways. FLIP will probably become an attractive death receptor signaling target of therapy.

Key words: FLIP, Apoptosis, Signaling pathway, Regulation