Current status and perspective of angiogenesis and antivascular therapeutic strategy: non-small cell lung cancer

Lung cancer is the leading cause of cancer death worldwide, and most patients die of metastatic disease. Angiogenesis, namely, neovascularization from preexisting vasculature, is necessary for tumor growth in both primary and distant organs to supply oxygen and nutrition. Angiogenesis consists of sprouting and nonsprouting (the enlargement, splitting, and fusion of preexisting vessels) processes, and both can occur concurrently. The growth of non-small cell lung cancer (NSCLC), which accounts for more than 80% of all lung cancers, is usually dependent on angiogenesis, which is regulated by complex mechanisms in the presence of various angiogenesis-related molecules. Vascular endothelial growth factor (VEGF), also known as vascular permeability factor (VPF), is one of the most potent angiogenic molecules, while also regulating both angiogenesis and vascular permeability and hence promoting tumor progression and the development of malignant pleural effusions in NSCLC. Recent clinical trials showed that the anti-VEGF antibody bevacizumab, combined with standard first-line chemotherapy, provided a statistically and clinically significant survival advantage with tolerable toxicity. In addition, the combined use of the anti-VEGF antibody with an inhibitor of epidermal growth factor receptor (EGFR) has also shown favorable antitumor efficiency. These successes proved the validity of an antivasculature strategy for NSCLC. Furthermore, a large number of antivasculature agents have been shown to be effective against multiple targets. The efficiency of these compounds is currently being investigated in clinical trials for NSCLC.