Nanog (EP225)

Nanog is a transcription factor homeoprotein that is involved in maintaining embryonic stem cell pluripotency and self-renewal.1-3 Embryonic stem cells with a deleted Nanog gene lose pluripotency. Conversely, embryonic stem cells that are forced to differentiate will down-regulate Nanog expression.1-2 Nanog expression has been shown to be absent in normal adult organ tissues, but positive expression in undifferentiated germ cell tumors such as seminoma, dysgerminoma and embryonal carcinoma has been noted.1,2,4,5 Therefore, Nanog may be used as an aid in the determination of undifferentiated tumors of germ cell origin from non-germ cell tumors.4,5