Immunodetection of the signal transducer and activator of transcription-3 in canine haemangioma and haemangiosarcoma.

The aim of this study was to examine the expression of signal transducer and activator of transcription 3 (STAT3) in canine haemangiomas and haemangiosarcomas. STAT3 protein was demonstrated in both the cytoplasm and nuclei of labelled cells. The expression of STAT3 was observed in 87.50% (35/40) of both haemangiomas and haemangiosarcomas and 72.22% (13/18) of haemangiomas and 100% (22/22) haemangiosarcomas. The percentage of positive cells in haemangiomas and haemangiosarcomas was statistically significant difference (P<0.0001). These preliminary results indicate that STAT3 is overexpressed in malignant tumours.