FGFR3 and oral cavity squamous cell carcinoma: For example, R669G, the most activating mutation with respect to FGFR3 kinase domain autophosphorylation, is not a mutation hotspot, whereas G697C (of oral squamous cell carcinomas [76]), an identified FGFR3 mutation hotspot, has no stimulatory effect on kinase activity over wild-type kinase domain under the analysed conditions [75].