Expression of Serotonin and its 5-HT1A Receptor in Canine Cutaneous Mast Cell Tumours

• Published in: Journal of comparative pathology 2009-08, Vol.141 (2), p.89-97
• Main Authors: Fröberg, G. Kastengren, Lindberg, R., Ritter, M., Nordlind, K.
• Format: Article
• Language: English
• Subjects: Animal and Dairy Science; Animals; Biomarkers, Tumor - metabolism; Cell Transformation, Neoplastic - metabolism; Cell Transformation, Neoplastic - pathology; dog; Dog Diseases - metabolism; Dog Diseases - pathology; Dogs; Fluorescent Antibody Technique, Direct - methods; Fluorescent Antibody Technique, Direct - veterinary; fluorescent labeling; Husdjursvetenskap; Immunoenzyme Techniques - methods; Immunoenzyme Techniques - veterinary; immunohistochemistry; mast cell tumors; mast cell tumour; mast cells; Mast Cells - metabolism; Mast-Cell Sarcoma - metabolism; Mast-Cell Sarcoma - pathology; Mast-Cell Sarcoma - veterinary; Medicin och hälsovetenskap; Neoplasm Staging - veterinary; neoplasms; receptor; Receptor, Serotonin, 5-HT1A - metabolism; receptors; serotonergic activity; serotonin; Serotonin - metabolism; serotonin receptors; skin; Skin - metabolism; Skin Neoplasms - metabolism; Skin Neoplasms - pathology; Skin Neoplasms - veterinary; Veterinary Science; Veterinärmedicin
• ISSN: 0021-9975; 1532-3129; 1532-3129
• DOI: 10.1016/j.jcpa.2008.08.002

Mast cells of a number of different animal species have been reported to contain serotonin (5-hydroxytryptamine; 5-HT), a monoamine capable of numerous and complex actions, which may include an impact on tumour growth. Limited previous studies have suggested that normal or neoplastic canine mast cells do not express 5-HT. In the present study, canine cutaneous mast cell tumours (MCTs) of Patnaik histological grades I–III were investigated immunohistochemically for expression of 5-HT and its receptor (R) 5-HT1A. The proportion of positively labelled cells and the intensity of labelling of individual cells were determined. Both 5-HT and the 5-HT1A receptor were expressed by non-neoplastic dermal mast cells and neoplastic mast cells. More neoplastic mast cells expressed 5-HT than the 5-HT1AR. Poorly differentiated tumours expressed fewer of both molecules, but the better differentiated mast cells at the periphery of such lesions had more consistent 5-HT expression. 5-HT and the 5-HT1A receptor may be involved in the differentiation of canine MCTs and in the microvascular complications associated with these neoplasms.