Lung cancer is the leading cause of death from cancer worldwide.  In the United States alone, 160,000 people are expected to die from lung cancer in 2007. These high lung cancer mortality rates are attributed to the fact that most patients are not diagnosed until they have advanced disease, for which there are few or no therapeutic options. As such, it is imperative to improve our very limited understanding of the nature of lung cancer cells in order to develop more effective therapies.

It has been known for many years that only a small fraction of the cells within a tumor are needed for tumor growth. These cells are now recognized as “cancer stem cells” because they, like the stem cells in normal tissues, are able to renew themselves. Although cancer stem cells represent only a small proportion of the tumor, they are believed to be more resistant to chemotherapy than the rest of the cells within a tumor. Therefore, in order to effectively treat cancer, it may be crucial to identify cancer stem cells and then develop therapies that specifically eliminate these key cells.

In the proposed studies we will focus on the specific goal of identification of cancer stem cells in bronchioalveolar carcinoma (BAC), a type of lung cancer that is particularly resistant to traditional therapeutic methods, and, therefore likely to contain cancer stem cells. Interestingly, BAC arises in the same part of the lung where I first identified stem cells in the mouse lung. Therefore, there may be similarities between the mouse lung stem cells we discovered and BAC stem cells, making our group uniquely positioned to study BAC. We have recently created a new test for lung cancer stem cells by transplanting subsets of tumor cells into recipient mice and comparing the ability of these subsets to give rise to new tumor growth. We will use this system to identify BAC stem cells and understand the properties that distinguish them from other tumor cells. Defining the methods to isolate BAC stem cells is a prerequisite to developing therapeutic strategies to eliminate the cells that allow BAC to grow. Our work will provide the first step towards identifying new ways to study and treat BAC.