While antral stem cells expressing Lgr5, Mist1 or Sox2 may be among the gastric cancer origin cells in the setting of Apc loss [16,23,37], Lgr5+ cells have been implicated in more invasive types of gastric cancer, characterized by the simultaneous loss of Pten and Smad4, or by the loss of Lats1 and Lats2 [38,39]. The gene discussed is SMAD4; the disease is gastric cancer.