| Background |
X-linked inhibitor of apoptosis (XIAP)-associated factor 1 (XAF1) is a zinc finger protein that antagonizes the anti-apoptotic activity of XIAP. XIAP, a member of the inhibitor of apoptosis (IAP) family, inhibits apoptosis by direct inhibition of caspases . XAF1 is widely expressed in normal tissues, with highest levels in the heart and ovary, but is mostly reduced in cancer lines . Expression of XAF1 can be induced by interferons via Stat transcriptional activity. The levels of XAF1 have been shown to be inversely correlated with p53, and p53 is directly responsible for inhibiting XAF1 transcription. A number of studies have shown that XAF1 can function as a tumor suppressor protein, and decreased levels of XAF1 are found in a variety of different cancers. Research studies suggest that expression of XAF1 may be a prognostic biomarker for some cancers.
|