Angiogenesis and breast cancer

The importance of angiogenesis in tumour progression and metastasis is well-recognized and has led to many developments; those with particular relevance to breast cancer are reviewed. There is now a clear understanding of the angiogenic switch, occurring as a discrete component of the tumour phenotype and depending on an alteration in the balance of angiogenic stimulators and inhibitors. The relationship between angiogenesis and oestrogen, which demonstrates an angiogenic effect, is examined. Clinical applications of breast tumour angiogenesis include its role as a prognostic indicator and potentially as a marker of treatment response. Therapeutic applications are under development, involving several different aspects of the angiogenic process and results of ongoing clinical trials are awaited with interest.