Monday 3 September 2007
WNTs proteins are extracellular signaling molecules involved in the control of embryonic development. There are at least 2 families of secreted inhibitors of WNT signaling:
the secreted frizzled-related protein family (as SFRP1; MIM.604156), all of which have an N-terminal cysteine-rich domain and are transmembrane receptors;
and the Dickkopf (German for ’big head,’ or ’stubborn’) family (as DKK1; MIM. 605189).
Chromosome rearrangements involving 12q13-15 are frequent among several tumors, including pleomorphic adenomas. The common molecular target for these aberrations is the HMGA2 gene, but various fusion partners of HMGA2 have been reported in tumors.
The WNT inhibitory factor 1 (WIF1) gene is also a HMGA2 fusion partner in salivary gland pleomorphic adenoma. WIF1 could be a recurrent target in human salivary gland oncogenesis and that downregulation of WIF1 plays a role in the development and/or progression of pleomorphic adenomas.