FGFR1 and gastrointestinal stromal tumor: In molecular subtypes of gastrointestinal stromal tumors (GISTs), which lack any of four common biomarkers referred to as quadruple WT GIST, FGF4 amplification and increased expression resulted in increased AKT activation downstream of FGFR1, and has been suggested as a therapeutic target in this molecular subtype [102].