Vascular endothelial growth factor: an important angiogenic mediator in bladder cancer

Angiogenesis is the growth of new blood vessels from existing ones and is critical for tumour development, invasion and metastasis. In bladder cancer the prognostic significance of mean vascular density, a surrogate for angiogenesis, has lead to study of the factors determining the angiogenic phenotype. The motivation for these studies has been the search for non-invasive prognostic or diagnostic markers for the disease and for new therapeutic strategies against bladder cancer recurrence and progression. Whilst a large number of factors are involved in the mediation of tumour angiogenesis, vascular endothelial growth factor (VEGF) is widely considered to be central to the process. This review highlights the information presently available regarding the role of VEGF in bladder cancer through observational studies of its expression in bladder tumours and within the urine. In addition the value of VEGF in determining the prognosis in bladder cancer and the future possibilities for anti-VEGF therapy are discussed.