Lung cancer is the leading cause of cancer mortality in the U.S. It is both a primary disease and a secondary, metastatic complication of other cancers. Recent research has discovered that the innermost layer of cells that line blood vessels, endothelial cells, are not uniform throughout the body. Advanced proteomic techniques have been employed to illustrate the differences in endothelial cell proteins and receptors lining blood vessels in different organs, and between blood vessels lining normal tissues and cancerous tumors. Proteins have been discovered in lung endothelial cells that promote the metastasis and invasion of the lung by other tumors, such as breast cancer. Differences in endothelial cell proteins and receptors between ethnic groups have been noted, and differences that extend to the level of individuals have been proposed.

The endoarterial biopsy catheter will provide a tool to obtain samples of endothelial and subendothelial cells from blood vessels lining lung cancer tumors safely and effectively in a minimally invasive fashion. Pulmonary endoarterial biopsy samples can also be obtained from cancer patients at risk for secondary lung cancer metastasis. Biopsy samples can be analyzed using sophisticated proteomic techniques in order to identify protein and receptors in patient’s endothelial cells.

Knowledge of a patient’s endothelial cell protein and receptor patterns could be used to deliver individualized therapies by creating therapeutic agents to specifically target those receptors and proteins. The information would allow physicians to diagnose and stage disease, as well as customize therapy according to each patient’s potentially unique pattern of endothelial cell protein expression. Identifying protein and receptor signatures in endothelial cells lining blood vessels adjacent to tumors would provide oncologists with a powerful tool to diagnose and customize treatment for lung cancer and prevent lung metastasis from other cancers.