BCL2 and odontogenic cyst: Nonetheless, previous studies indicated that the expression of apoptosis-regulating factors may vary according to the structure of the epithelial lining and the inflammatory components present in PCs and other odontogenic cysts.7,22,23 Loyola, et al.17 (2005) showed greater Bcl-2 expression in lesions with atrophic epithelial lining than in those with hyperplastic epithelial lining, although the authors found no significant difference between the groups studied.