Tyrosine-protein kinase receptor UFO is an enzyme that in humans is encoded by the AXLgene. The gene was initially designated as UFO, in allusion to the unidentified function of this protein. The AXL protein is a cell surface receptor.
The Axl gene is evolutionarily conserved between vertebrate species. This gene has two different alternatively spliced transcript variants.
The protein encoded by this gene is a member of the receptor tyrosine kinase subfamily. Although it is similar to other receptor tyrosine kinases, the Axl protein represents a unique structure of the extracellular region that juxtaposes IgL and FNIII repeats.
There is ongoing research to develop possible drugs to target this signalling pathway and treat cancers. In 2014 those in clinical trials included::Table 2 LY2801653, MP-470 (Amuvatinib), SKI-606 (Bosutinib), MGCD 265, ASP2215, XL184 (Cabozantinib), GSK1363089/XL880 (Foretinib), SGI-7079, and R428 (BGB324).
e.g. ASTELLAS is currently testing ASP2215 (Gilteritinib), a dual FLT3-AXL tyrosine kinase inhibitor in acute myeloid leukemia (AML).
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