We assessed by immunohistochemistry (IHC) analysis whether there was a differential expression of Ubc9 in different grades of cervical intraepithelial neoplasia (CIN), also referred to as HSILs (high-grade squamous intraepithelial lesions) or LSILs (low-grade squamous intraepithelial lesions)) from HPV-positive patients. Here, UBE2I is linked to squamous cell intraepithelial neoplasia.