YAP1 and soft tissue sarcoma: For example, fusion genes involving WWTR1 and YAP1 are found in nearly all cases of epithelioid haemangioendothelioma [63,64]; YAP1 copy number gain has been described in embryonal rhabdomyosarcoma [65] and frequent hypermethylation of MST1, MST2 and RASSF1A has been shown in several subtypes of soft tissue sarcoma [66].