Fig. 1.

Higher susceptibility of tumor initiation from Keratin5⁺ (Krt5⁺) progenitors near the SCJ. a, b Experimental scheme. c Oncogenic Ras/p53-mediated tumor formation throughout the forestomach tissues. d Experimental scheme. e, f Histological phenotype of early tumor initiation and higher tumor incidence from tumor-prone Krt5⁺ progenitors resident at regions adjacent to the SCJ (n = 8 animals per each). Statistical significance was determined by Fisher’s exact test; ns = not significant, **p < 0.005. g, h Histological phenotype of early tumor initiation and tdTomato lineage tracing. i Summary of early tumor formation from tumor-prone Krt5⁺ basal progenitors expressing oncogenic Ras/p53 combination. FS, forestomach; HS, hindstomach; SCJ, squamocolumnar junction; Tmx, tamoxifen. Scale bars, 100 µm