SOX2 and neoplasm: Two conclusions can be drawn from these studies: (i) SOX2+ve stem cells are not the cell of origin of ACP; however, they are the origin of the typical cell clusters that characterize these neoplasms; (ii) mutated SOX2+ve cells expressing oncogenic β‐catenin are not CSCs according to the classical definition of the CSC paradigm, since their descendants do not colonize the tumours, rather they induced tumours in a non‐cell autonomous manner.