Angiopoietin-like 4 is a protein that in humans is encoded by the ANGPTL4 gene.This gene is a member of the angiopoietin/angiopoietin-like gene family and encodes a glycosylated, secreted protein with a coiled-coil N-terminal domain and a fibrinogen-like C-terminal domain. The encoded protein may play a role in several cancers and it implicated in the metastatic process by modulating vascular activity as well as tumor cell motility and invasiveness. ANGPTL4 contributed to tumor growth and protected cells from anoikis, a form of programmed cell death induced when contact-dependent cells detach from the surrounding tissue matrix.
Background References
1. "Inhibition of angiogenesis and vascular leakiness by angiopoietin-related protein 4." Ito Y., Oike Y., Yasunaga K., Hamada K., Miyata K., Matsumoto S., Sugano S., Tanihara H., Masuho Y., Suda T. Cancer Res. 63:6651-6657(2003)
2. "Angiopoietin-like protein 4 decreases blood glucose and improves glucose tolerance but induces hyperlipidemia and hepatic steatosis in mice." Xu A., Lam M.C., Chan K.W., Wang Y., Zhang J., Hoo R.L., Xu J.Y., Chen B., Chow W.S., Tso A.W., Lam K.S. Proc. Natl. Acad. Sci. U.S.A. 102:6086-6091(2005)
Tissue Specificity
Detected in liver and kidney. Predominantly expressed in adipose tissue and is strongly up-regulated by fasting in white adipose tissue and liver.
Post-translational Modification
N-glycosylated.; [ANGPTL4 N-terminal chain]: Forms disulfide-linked dimers and tetramers.; Cleaved into a smaller N-terminal chain and a larger chain that contains the fibrinogen C-terminal domain; both cleaved and uncleaved forms are detected in the extracellular space. The cleaved form is not present within the cell.