Mast cells and tumour angiogenesis: new insight from experimental carcinogenesis.

Histopathologic examination and clinical observations of solid and haematological malignancies indicates mast cells as key host cells in the tumour infiltrate, with important consequence on tumour-associated angiogenesis and tumour growth. Data suggest indeed that tumour-infiltrating mast cells may exert a prominent function in the angiogenic "switch", which is essential for the progression of early tumours. The experimental approach has substantially increased our understanding of the role of tumour-infiltrating mast cells in the process of angiogenesis that accompanies tumour development. This review will focus on the crucial contribution of mast cells in promoting tumour neovascularization as it emerges from the most recent observations of experimental carcinogenesis in in vivo and in vitro models.