Survivin Expression In Canine Tumours With Sebaceous Differentiation

Introduction: Survivin is a member of the inhibitor of apoptosisprotein (IAP) family and exhibits low expression in most normaladult tissues. Elevated expression in tissues during embryonic developmentand in the majority of cancers, as well as in human sebaceoustumours, indicates potential diagnostic utility. In normal adulthuman skin, survivin has been recently proposed as a marker for keratinocytestem cells.Materials and Methods: Fifteen canine tumours with sebaceousdifferentiation (2 carcinomas, 9 adenomas, 1 epithelioma, 3 hyperplasia)and five specimens of normal canine skin were evaluated histologicallyand immunohistochemically. Full-length survivin (0.7 mg/ml,rabbit polyclonal antibody, NOVUS Biologicals) expression was correlatedwith p53 (1 in 400, rabbit polyclonal anti-human antibody,CM1, Novocastra) expression and mitotic index (MI).Results: Survivin-positive nuclei in normal sebaceous glands werefew and scattered. Pre-neoplastic lesions and benign tumours showedseveral survivin-positive nuclei and, apart from one case, there was noevidence of p53 expression. Numerous survivin-positive nucleioccurred in carcinomas together with a higher mitotic index andlarge numbers of p53 positive nuclei.Conclusions: The present study revealed for the first time that indogs, as in man, nuclear survivin expression is increased in sebaceouscarcinomas compared with normal glands and benign lesions. Thefindings suggest a direct correlation with biological behaviour, consistentwith the anti-apoptotic and proliferative functions of themolecule.[...]