Immunolocalization of Bcl-2 oncoprotein in amlodipine-induced gingival overgrowth

Abstract

Drug-induced gingival overgrowth (DIGO) is one of the unwanted side effects of amlodipine therapy, but the pathogenesis still remains unclear. Apoptosis, which plays a ubiquitous role in tissue homeostasis, including gingiva, may be involved in the development of gingival enlargement. (i) To study the distribution of Bcl-2 in healthy and overgrown gingival tissues. (ii) To compare and correlate the Bcl-2 expression in gingival samples from subjects on amlodipine therapy to the findings in healthy controls. A total of 25 subjects were recruited for the study - 15 hypertensive patients and 10 systemically healthy subjects. Both the groups were analyzed for Bcl-2 expression using immunohistochemistry. Few of the control specimens showed weak positivity to Bcl-2 antibody, with the distribution limited to the basal cell layers alone, whereas 10 hyperplastic specimens expressed Bcl-2 and, unlike the control group, the distribution pattern was seen in both basal and suprabasal layers. The results indicate that the pathogenesis of amlodipine-induced gingival overgrowth might involve inhibition of apoptosis, especially with morphogenesis of hyperplastic gingival epithelia.