NANOG and cancer: The list of over-connected proteins includes: (i) Snail, Slug and Twist1 consistent with their previously recognized role in EMT [25]; (ii) GSK3B, RYK, β-catenin (CTNNB1) and TCF7L2 (TCF4) consistent with a role in the Wnt signaling pathway in Snail-induced EMT [10]; (iii) ESR1, PGR (PR) and androgen receptor suggesting a role of the sex-hormone-receptor-mediated signaling pathway; (iv) cancer-associated transcription factors p53 (TP53) and c-Myc (MYC), and (iv) the pluripotency-associated transcription factors KLF-4, Oct3/4, Nanog, Sox2 [35, 36].