Angiogenesis plays a crucial role in tumour growth, invasion and metastasis. Mast cells (MCs) release angiogenic factors that promote endothelial proliferation and differentiation. Previous studies have suggested that MCs are involved in tumour angiogenesis due to the release of various pro-angiogenic factors. This study evaluated samples from 40 canine mammary carcinomas and eight healthy non-neoplastic canine mammary glands. Toluidine blue staining was performed to characterize the MCs. Immunohistochemical labelling was performed to detect the number of tryptase-positive MCs and microvessels. MCs accumulated in tumour tissue and were closely associated with blood or lymphatic vessels in the tumour microenvironment. Angiogenesis, as measured by microvessel density, increased in direct proportion to the number of MCs. The correlation coefficient was significantly higher for tryptase-positive MCs than for toluidine blue-stained MCs. These results suggest that MCs are involved in tumour angiogenesis, which in turn influences tumour growth, invasion and metastasis. In particular, MC tryptase may be influential in mediating this function of MCs.
Bibliographical noteFunding Information:
The authors thank Ms. R.-H. Jang for excellent technical assistance and the participating private veterinary clinics for providing access to samples of canine mammary gland tissues. This study was supported by a grant from the Konkuk University Research Foundation 2010 . This report represents one part of a PhD thesis by K.-S. Im.
Copyright 2012 Elsevier B.V., All rights reserved.
- Canine mammary carcinomas
- Mast cell
- Mast cell tryptase