HCFC1 and cervical squamous intraepithelial neoplasia: Consistently, immunohistochemical analysis showed that levels of O-GlcNAc, OGT, HCF-1, and HPV16/18 E6 were significantly increased, particularly in the intermediate layer of cervical cancer tissues compared to normal cervical tissues, paralleling staining of Ki-67 (Figure 1E), a DNA proliferation marker increased in cervical intra-epithelial neoplasia (CIN) [20].