YAP1 and gastric neoplasm: To assess the impact of impaired Yap1 expression in gastric tumors, we generated a Gp130FF; Tff1:CreERT2; Yap1fl/fl compound mutant mice and used tamoxifen-induced activation of Cre-recombinase to delete exon 3 of the Yap1 gene, specifically in gastric epithelial cells in the mucosal layer of the corresponding Gp130FF; Yap1KO mice (Fig S3A and B) (25).