Expression of Endothelin-1 and Endothelin Receptor A in Canine Ovarian Tumours

Ovarian tumours have a low incidence in bitch. Endothelin (ET‐1) and endothelin A receptor (ET‐A) are overexpressed in human ovarian cancer. Twenty canine ovarian tumours and five normal samples were first evaluated by western blotting and then immunohistochemically for ET‐1 and ET‐A expression. Seventeen out of twenty tumours were ET‐1 positive. Eight out of twenty tumours were ET‐A immunohistochemically positive. At molecular level both proteins were proven to be expressed in normal as well as in tumour samples. Our results show that ET‐1 and ET‐A are overexpressed in canine ovarian tumours, suggesting a potential role of these two molecules in canine ovarian carcinogenesis.