SMAD2 and cervical cancer: Roles of several transcription factors, such as SOX2, E2F4, E2F1, POU5F1, SMAD3, SMAD2, VDR, ERG, TP53, EWS, c-fos, fra-1, OCT4, KLF4, C-MYC, and NANOG, were established in cervical cancer (80, 81).