PROM1+, but not PROM1−, cells isolated from P1KP gastric adenocarcinomas (P1KP-GAC) propagated these tumors as allografts, suggesting that PROM1+P1KP-GAC cells are the malignant counterparts of antral gland basal stem cells (Extended Data Fig. 1). The gene discussed is PROM1; the disease is gastric adenocarcinoma.