Expression of target molecules in lung cancer: challenge for a new treatment paradigm

Lung cancer is the leading cause of cancer death in men and women in the United States, accounting for 28% of all cancer fatalities. More than two thirds of patients present with metastatic disease at the time of presentation. Despite improvements in chemotherapy and combined treatment modalities, the survival rate remains below 15%. However, recent advances in our understanding of the biology of lung cancer and carcinogenesis have led to the development of novel therapies directed at tumor-specific targets. These targets are crucial components in important pathways for cell growth, proliferation, and apoptosis. Strategies that interfere with these pathways include monoclonal antibodies directed at growth factors or their receptors, immunotoxins, ligand toxins, antisense molecules, ribozymes, and small-molecule inhibitors. Novel cell surface antigens are being used in vaccines developed to stimulate T-cell-specific immunity. The tumor cells also have specific survival requirements in their local environment that are necessary for invasion, angiogenesis, and metastases. Many new therapeutic strategies are designed to interfere with these requirements. This article reviews many of these recent developments and new therapeutic possibilities; ideally, in the near future, these developments will be implemented in the treatment of lung cancer patients and in early detection and chemoprevention strategies.