In line with this idea, VENTX is co-expressed with NANOG and POU5F1 in pluripotent-embryonal carcinomas [73], a subtype of human male germ cell tumours constituted of cells highly similar to early zygotic and ES cells [74], and these three genes are strongly down-regulated when tumour cell differentiation is forced in vitro[73]. Here, NANOG is linked to testicular germ cell tumor.