Cyclosporine A-induced gingival overgrowth: A comprehensive review

Cyclosporine A, an extremely effective immunosuppressant, is also associate d with various untoward effects, including gingival overgrowth. Despite int ense clinical and laboratory investigation, the cellular-molecular mechanis m through which cyclosporine A simultaneously acts as a selective immunosup pressant while it elicits a connective tissue reaction in the gingiva remai ns poorly understood. In recent years, cellular and molecular biologic tech niques have elucidated a variety of growth factors that control connective tissue homeostasis. Two growth factors known to be major elements in wound repair and connective tissue homeostasis are platelet-derived growth factor and transforming growth factor-beta 1. Increased gingival levels of these factors may be responsible for promoting fibroblastic proliferation and fib roblastic production of extracellular matrix constituents in overgrown ging ival tissues. Expression of these factors has recently been shown to be upr egulated in these tissues. The results of these recent studies may provide a foundation for understanding the molecular mechanism involved in the path ogenesis of cyclosporine A-induced gingival overgrowth.