YAP1 and cancer: YAP and TAZ, key transcriptional co-activators of Hippo signaling, are intimately associated with tumorigenesis, proliferation, stemness, autophagy, recurrence, immunosuppression, and RTx resistance in cancer broadly.31, 41–44 Although IGF1R regulation of YAP1 has only recently been implicated in GBM,45 the underlying mechanisms remain incompletely defined.