Breast cancer is the most common female cancer. Despite advances in prevention, early diagnosis, and surgical treatment, its
prognosis is still poor. Therefore, immunological and pharmacological methods of treatment have been emphasized recently. Prominent
targets of drugs or antibodies are proteins, which are predominantly expressed on breast cancer cells and are simultaneously involved in
promoting cell growth or apoptosis. However, breast cancer is a heterogeneous disease, because breast cancer cells may show a variety of
malignant gene expression patterns. Therefore, it is difficult at the current state of technology, to apply the optimal cocktail of drugs to hit
all cancer cells of any given patient.
Under these circumstances, the option of targeting more tractable, normal cells surrounding the tumor instead of the less heterogeneous
ones, preventing them from supporting tumor cell growth, became particularly interesting. Endothelial cells are important supporters of
cancer cell growth. As a rule, tumors induce them to grow out and to develop a tumor vasculature, which enables the cancer cells to survive
and to spread. The introduction of inhibitors of neovascularization was therefore an important milestone on the way toward treating
breast cancer more successfully. It has already been demonstrated that the blockade of vascular endothelial growth results in regression of
the disease and first clinical studies seemed to hint toward a beneficial effect on prolongation of survival. Nevertheless, more clinical and
basic research is necessary to improve this therapy approach.
This review will compile the knowledge about recently developed anti-angiogenic drugs in the treatment of breast cancer and will provide
an overview on currently relevant clinical trials