Figure 4.

Reversion of pluripotent cells between normal and cancers. Embryonic (e) or induced (i) pluripotent stem (PS) cells introduced into the blastocyst in the uterus can develop to live animals (a). However, if the cells are transplanted to extrauterine sites of adult animals, they will likely develop to teratomas or teratocarcinomas (b). If teratocarcinoma cells are inoculated into the blastocyst, they will be incorporated into the developing embryo, and the tissues of the animal developed from the embryo will be chimeric, i.e. containing cells from both the embryo and the cancer (c). Moreover, if inoculation of the nuclei isolated from the Kucké renal cancer cells of the frog origin into enucleated frog eggs, the eggs can hatch out live tadpoles with all tissues normal (d).