SMAD4 and cervical squamous intraepithelial neoplasia: Late-onset CIN tumors often lose chromosomal loci containing SMAD4, DCC and APC genes, whereas early onset CIN tumors gain chromosomal loci with BMPR1A and AMP-kinase regulatory subunits and lose loci containing FOX transcription factors and TJP2, a CRC marker [31].