Antiangiogenic therapy in cancer

Traditional cancer therapies make use of chemotherapy at the maximum tolerated dose (MTD), generally resulting in significant toxicities and often with limited success. The so-called "targeted therapies" such as Iressa (R) (gefitinib) or Gleevec (R) (imatinib mesilate) are considered less toxic and provide further ammunition in the fight against cancer, but often produce responses in only a limited number of cancer patients. The need for new, more universal, more effective and less toxic therapeutic modalities is therefore evident. Angiogenesis is generally defined as the sprouting of new vessels from pre-existing ones and is an essential process for the growth and maintenance of tumors. Antiangiogenic therapy is potentially of very broad application in cancer, safe and possibly highly effective. More than 300 angiogenesis inhibitors have been identified and approximately 80 are currently in clinical trials. In 2004, the first antiangiogenic agent was approved in combination with chemotherapy for the treatment of metastatic colon cancer. This review describes recent advances in antiangiogenic therapy for cancer.