In contrast with the effects of metaplasia- or cancer-derived fibroblasts on metaplastic cells, true normal-derived fibroblasts, isolated from histologically normal corpus mucosa without metaplasia or neoplasia obtained from the distal margins of esophagogastrectomies, did not promote polyp formation or expression of TROP2 or CEACAM5 compared with gastroid cells alone (Supplementary Figure 12B–D). This evidence concerns the gene CEACAM5 and neoplasm.