Focal cortical dysplasia type II (malformations of cortical development) aberrantly expresses apoptotic proteins

bcl-X-L, bax. bcl-2, and p53 arc apoptotic proteins essential to normal neural development. Aberrant expression of' these proteins has been observed in several central nervous system neoplasms. Immunoexpression of these markers is studied in 21 patients with focal cortical dysplasia type II (Taylor-type cortical dysplasia: malformations of cortical development) who had undergone lesionectomy for treatment of pharmacoresistant epilepsy. Paraffin immunohistochemistry using standard methodology was performed on representative sections using antibodies to bcl-X-L. bax. bcl-2 in 71%, 76%, and 24% of cases. respectively, and ballon cells staining positively for bcl-X-L. bax, and bcl-2 in 89%, 78%, and 17% of cases, respecitvely. Most cases (86%) showed some expression of p53, with the majority showing expression of p53 most prominently in balloon cells. Previous work has shown gangliomas and dysembryo-plasic neoplasms. to demonstrate aberrant expression of apoptotic markers, suggesting a possible common mechanism of development for these 2 processes in patients in whom they coexist.