ORIGINAL ARTICLE Proliferation, Apoptosis, and Survivin Expression in

Abstract: The dysregulation of apoptosis occurs in many cutaneous disease states. Several apoptosis inhibitors have been shown elevated in neoplasms and in some inflammatory conditions, but their relation to proliferative and apoptotic states has not been defined. We exam-ined the expression of the apoptosis inhibitor survivin in a panel of keratinocytic neoplasms and hyperproliferative skin lesions using both immunohistochemistry and a newly developed in situ hybridiza-tion technique. Proliferation and apoptotic indices were also assessed by immunohistochemical staining for proliferating cell nuclear anti-gen and TUNEL, respectively. We found the highest rate of prolifera-tion in verrucae and psoriasis followed by actinic keratosis, squamous and basal cell carcinoma, lichen simplex chronicus, and seborrheic keratosis; all were significantly (P < 0.05) higher than normal skin. Apoptotic rate was increased in squamous (P = 0.05) and basal cell carcinoma (P = 0.03), but not significantly different from normal skin in the other lesions tested. Survivin expression was seen in most neo-plasms and hyperproliferative lesions, but not normal skin. Survivin expression was often restricted to the upper third of the epidermis in psoriasis and lichen simplex chronicus, whereas all the other lesions stained diffusely. Survivin expression appears to be a consistent fea-ture of keratinocytic neoplasms and hyperproliferative lesions and may contribute to the formation of epidermal hyperplasia seen in all of these disease states