Apoptotic changes in cervical intraepithelial neoplasia

We examined apoptosis in paraffin-embedded archival cervical tissues from cervical intraepithelial neoplasia (CIN) cases to determine whether the apoptotic process is involved in the cellular changes of CIN. Apoptotic bodies, determined by the Tunel method, were largely found at the surface epithelium in a few tissue specimens with no significant abnormality and in most tissues with CIN. Apoptotic bodies were also found within the stratified epithelium of CIN lesions and were altogether absent in specimens with no significant abnormalities. The apoptotic index was significantly associated with the severity of CIN and not with either age or human papillomavirus infection. Based on the findings of increased numbers of apoptotic bodies and their presence within the stratified epithelium in CIN tissues, we hypothesize that dysregulation in the exfoliation of apoptotic cells and resistance towards apoptosis may be prerequisites for the pathogenesis of CIN.