YAP1 and neoplasm: We employed conditional expression of the HPV16 E6-E7 oncogenes to concomitantly inhibit the TP53 and CDKN2A tumor suppressors.16 Given the frequency of FAT1 mutations and widespread YAP nuclear expression in HNSC,17 we investigated the effects of YAP activation in conjunction with E6-E7 by expression of the YAP1S127A allele.