Expression of Stat3 in feline mammary gland tumours and its relation to histological grade.

The expression of Stat3 (signal transducer and activator of transcription 3) in normal and neoplastic feline mammary gland tissue was assessed by immunohistochemistry in 72 cats. The samples included 3 normal nonlactating mammary tissues, 17 hyperplastic lesions (11 lobular and 6 fibroepithelial) and 52 neoplasms (5 benign and 47 malignant). For immunohistochemistry, tissue sections were incubated with anti-Stat3 monoclonal antibody and visualized with EnVision-DAB polymer.