[Tumor-host interactions in the progression of breast cancer].

Breast carcinomas are composed of different compartments: tumor epithelial cells and host cells such as fibroblasts. Cancer progression and metastasis formation depend on complex interactions occurring between these two cell types. In response to the presence of tumour cells, fibroblasts secrete proteases able to degrade the extracellular matrix and to promote tumor invasion. These proteases are potential targets for anti-cancer agents.