Figure 4From: Cancer stem cells – the current status of an old concept: literature review and clinical approachesThe historical concepts of CSCs origin. A - Embryonal rest theory. The pluripotent embryonal cells remain in the adult organism in the form of “embryonal rest”. They are the origin of CSCs. B - Dedifferentiation theory. Somatic stem cells of adult tissue gain pluripotency through dedifferentiation.Back to article page