NANOG is a divergent homeobox protein and a core component of the transcriptional circuitry that sustains pluripotency and self-renewal. NANOG, as a key regulator of pluripotency and acting synergistically with other factors, has been described as a crucial transcription factor in various types of cancer.NANOG plays a pivotal role in pluripotency acquisition and lineage specification in higher vertebrates, and its expression is restricted to primordial germ cells (PGCs) during early embryonic development. Mammalian NANOG self-associates via conserved tryptophan-repeat motifs in the C-terminal domain (CTD) to maintain pluripotency.The NANOG homeobox gene plays a pivotal role in self-renewal and maintenance of pluripotency in human, mouse and other vertebrate embryonic stem cells, and in pluripotent cells of the blastocyst inner cell mass.NANOG, a marker of stemness, impacts tumor progression and therapeutic resistance in cancer cells.