A simplified model of suggested hypothesis about origin of the cancer stem cells. The cancer stem cells may develop when self-renewing normal stem cells acquire mutations and are transformed by altering only proliferative pathways. It is also possible that the cancer stem cells originate by multiple oncogenic mutations in the restricted progenitor cells which acquire the capability of self-renewal (Created from NEJM ).
Sagar et al. Cancer Cell International 2007 7:9 doi:10.1186/1475-2867-7-9