Putative adenosylhomocysteinase 2 (AHCYL1 aka adenosylhomocysteine hydrolase-like protein 1) (Dekker et al. 2002) possesses 50% homology to adenosylhomocysteine hydrolase (AHCY), an enzyme important for metabolizing S-adenosyl-l-homocysteine. AHCYL1 can bind to the inositol 1,4,5-trisphosphate receptor (ITPR1) tetramer, suggesting that AHCYL1 is involved in modulating intracellular calcium release (Cooper et al. 2006).
FGFR2 fusions in cholangiocarcinoma and cancers of the breast, lung and thyroid have been shown to promote anchorage independent growth, cellular proliferation and tumorigenesis. In some cases, such as for FGFR2-AHCYL1 and FGFR2-BICC1 fusions in cholangiocarcinoma, these activities have been shown to depend on the FGFR2 kinase domain, suggesting that the fusions undergo autophosphorylation after oligomerization, as is the case for WT FGFR2. FGFR2 fusions, where tested, also show sensitivity to kinase inhibitors such as PD173074 and pazopanib (Arai et al, 2013; Wu et al, 2013; Seo et al, 2012; reviewed in Parker et al, 2014).
FGFR2 fusions have been identified in cancers such as lung, breast, thyroid and cholangiocarcinoma (Wu et al, 2013; Seo et al, 2012; Arai et al, 2013). Of all the FGF receptors, FGFR2 shows the broadest range of 3' fusion partners, including BICC1, AHCYL1, CIT, CCDC6, CASP7, AFF3, OFD1 and CCAR2. Many of these fusion partners contain dimerization domains, suggesting that the resulting fusions may demonstrate constitutive ligand-independent activation (Wu et al, 2013; Arai et al, 2013; Seo et al, 2012; reviewed in Parker et al, 2014).