Our laboratory focuses on the role of chronic inflammation in the progression of breast cancer. We have shown that the inducible nitric oxide synthase (iNOS), an enzyme upregulated in response to proinflammatory stimuli promotes tumorigenesis in the mouse mammary tumor virus - polyomavirus middle T antigen (PyMT) mouse model of breast cancer. We have developed stable cell lines from these tumors to aid in studying the role of iNOS in tumorigenesis and metastasis. We are currently characterizing the cancer stem cell properties of PyMT tumor cell lines to determine the relationship between different breast tumor subtypes and how they may be modulated by proinflammatory stimuli. In collaboration with Dr. Roger Tsien and his group these cell lines have been used to develop imaging methods that are targeted to tumor cells by their release of the proinflammatory matrix metalloproteinases MMP2 and MMP9. Our interest in inflammation and breast cancer has also led to a collaboration with Dr. Jerold Olefsky and his group to examine the role of obesity and its associated inflammation in postmenopausal breast cancer progression. Thus the PyMT spontaneous model and tumor cell lines have proven to be valuable tools for the study of inflammation and breast cancer. We are currently using the cell lines to identify specific genes that may be biomarkers or therapeutic targets for breast cancer stem cells.