Metallothionein expression in canine cutaneous apocrine gland tumors.

BACKGROUND The aim of the present study was to evaluate, by immunohistochemical staining, metallothionein expression in normal, benign and malignant canine apocrine gland tissues and to correlate the protein expression with the histological grade of malignancy. MATERIALS AND METHODS MT immunostaining was evaluated in 25 formalin-fixed and paraffin-embedded canine apocrine glands (2 normal and 23 neoplastic). Moreover, we evaluated quantitative expression of MT in normal and neoplastic cells by western blotting. RESULTS a marked increase in MT expression was observed in neoplastic, compared to normal samples as well as in malignant compared to benign tumors. Western blotting analysis revealed one major protein band of approximately 14 kDa in normal, as well as in the neoplastic, tissues. CONCLUSION We conclude that MT expression appears to be a potential biomarker for the diagnosis of canine apocrine gland tumors and may also assist in the better understanding of the evolution of this neoplasia.