Baculoviral IAP repeat-containing protein 5 is a protein in humans that is encoded by BIRC5 gene. Multitasking protein that has dual roles in promoting cell proliferation and preventing apoptosis.
Baculoviral IAP repeat-containing protein 5 (BIRC5), also known as survivin, is a protein in humans that is encoded by the BIRC5 gene. Survivin contains a coiled-coil (CC) domain that interacts with chromosomal passenger proteins (including INCENP and borealin) and maintains the residency in the nucleus, and only one BIR domain that makes this protein unique compared to the other IAP family members. The survivin protein is highly expressed in most human tumors and embryonic tissues but is barely detected in terminally differentiated cells. Tamm I. et al. have shown that survivin inhibits both Bax and Fas-induced apoptotic pathways. Survivin also plays a role in regulating cell mitosis. The upregulation of survivin causes the functional loss of wild type p53. Tumors with high expression of survivin generally bear a poor prognosis and are associated with resistance to therapy. The expression of survivin is differential between cancer and normal tissues, making this protein a useful tool in cancer diagnosis and a promising therapeutic target. A growing body of literature suggests the nuclear expression of survivin as a good prognostic marker. Disruption of the survivin induction pathway has increased apoptosis and inhibited tumor growth.