Pro-metastatic tumor-stroma interactions in breast cancer.

The vast majority of breast cancer-related deaths are due to metastatic disease. Reciprocal and complex interactions between epithelial tumor cells and the various components of the tumor microenvironment influence tumor progression and metastases although the molecular mechanisms underlying these metastasis-promoting effects are not fully characterized. Identifying and understanding pathways of tumor-stroma cross-talk are likely to lead to the development of novel prognostic biomarkers for metastasis and strategies to prevent metastasis at its earliest stages, resulting in improved patient outcomes.