YAP1 and colitis: Consistent with recent studies describing YAP activation as an integral part of the regenerative and foetal programmes of the normal intestinal epithelium (Yui et al., 2018), we found a robust association with the reported physiological ‘foetal human colitis’ intestinal signature (Yui et al., 2018; Figure 4B and E), suggesting a link between the morphological change we characterised and reactivation of regenerative/foetal programmes occurring during tumorigenesis.