NANOG and cervical cancer: Recently, accumulating evidence showed that some stem cell self-renewal-associated transcription factors are involved in tumorigenesis and tumor development in cervical cancer; for example, NANOG, OCT4, Msi1 and LGR5 are reported to promote the progression of cervical cancer [9–12]; in contrast, UTF1 and KLF4 are reported to function as tumor suppressors in cervical cancer [13, 14].