Downregulation of Clusterin Expression in Testicular Germ Cell Tumours

Abstract

OBJECTIVES: Clusterin is implicated in many biological processes including cell adhesion, apoptosis and transformation. Clusterin expression was demonstrated during sperm maturation and is overexpressed in different malignancies including breast and prostate carcinomas and anaplastic large-cell lymphomas. METHODS: The aim of this study was to determine the expression of clusterin in a series of different germ cell tumours by immunohistochemistry. Twenty-two seminomas, 27 embryonal carcinomas, 22 mature and immature teratomas, 8 yolk sac tumours and 1 chorion carcinoma as well as 30 normal testes were analysed using a monoclonal antibody. RESULTS: In normal testes strong signals were seen in the maturing germ cells and in Leydig cells. In most tumours examined no clusterin expression was detected (84%). Only a focal weak expression was seen in some teratomas (32%), embryonal carcinomas (15%) and yolk sac tumours (25%). CONCLUSIONS: Our results suggest that clusterin is associated with normal germ cell development and that the loss of clusterin expression might play a role in the malignant transformation of germ cells.