Since FGFR4 is rarely mutated and the G388 polymorphism is not associated with the pro-survival activities of FGFR4, we asked whether the constitutively active FGFR4 signaling in cancers could be activated by an autocrine signaling loop, as has been demonstrated in other FGFR family members [65]. This evidence concerns the gene FGFR4 and cancer.