Jann Sarkaria, MD is a physician-scientist and Professor of Radiation Oncology at the Mayo Clinic in Rochester, Minnesota. His clinical focus is treating lung and brain malignancies with external beam photon or proton radiation. His laboratory work focuses on developing novel therapeutic strategies for treating both primary and metastatic brain tumors. Central to this work is the development and characterization of a large panel of patient-derived xenografts (PDXs) developed from brain tumor resection specimens. His laboratory has used these PDX models extensively to evaluate the efficacy of conventional and molecularly targeted therapies for glioblastoma (GBM). Central research themes include evaluation of genetic and epigenetic mechanisms of therapy resistance to radiation and temozolomide, development of novel radio- or chemo-sensitizing agents for brain tumors, and understanding the influence of heterogeneous drug delivery into brain tumors on treatment response and evolution of therapy resistance. All of these themes are highly translational with an ultimate goal of improving therapy for brain tumors.