Analysis of Proliferation, Apoptosis, and Keratin Expression in Cultured Normal and Immortalized Human Buccal Keratinocytes

The study analyzed the growth and differentiation functions of normal keratinocytes (NOK) and an SV40T-immortalized keratinocyte line (SVpgC2a) from buccal mucosa, using the latter as a model for dysplastic epithelium. It was found that SVpgC2a exhibited three- to five-fold higher apoptotic and proliferative activity compared to NOK. Serum conditions did not significantly affect NOK but supported SVpgC2a proliferation. Both cell types expressed basal lamina markers and vimentin, indicating a proliferative state. SVpgC2a showed reduced keratin expression, including the non-keratinizing marker K13, and transcribed keratins associated with epithelial dysplasia. The findings suggested aberrant apoptosis, proliferation, and keratin expression in SVpgC2a, modeling the progression from normal to pre-neoplastic buccal epithelium.