The focus of the Brown lab is on the influence of the tumor vasculature on the response to cancer treatment, particularly radiotherapy, which is used in the treatment of approximately 50% of all cancer patients. They therefore study tumor angiogenesis, defined as the development of tumor blood vessels by sprouting from nearby normal vessels, and vasculogenesis, defined as the development of tumor blood vessels de novo from circulating cells. They have found that the growth of tumors post irradiation relies largely on the recruitment of cells that make up and/or promote the continued growth of tumor blood vessels. These cells derive from the bone marrow and other tissues. The lab is investigating this phenomenon and are developing several methods of preventing the influx of these circulating cells into the tumors with the goal of sensitizing tumors to radiotherapy.