The goal of the Lee laboratory is translational breast cancer research. The laboratory has two main areas of focus. The first involves targeting the insulin-like growth factor pathway in breast cancer. A major emphasis is upon the downstream signaling intermediates the insulin receptor substrates (IRSs) analyzing interactions with steroid hormone receptors (ER and PR), role in normal mouse mammary gland development, mechanisms of transformation of mammary epithelial cells in vitro and in mouse models, and roles in human breast cancer. The second area of research is studies on tumor heterogeneity and molecular changes during progression, with a particular focus on DNA and RNA structural rearrangements. The laboratory participated in the first comprehensive report of structural rearrangements in a breast cancer cell line (MCF7) and reported on a novel massively parallel fosmid-based mate-pair assay for determining structural rearrangements. This work focuses on different tumor areas, or tumors from different parts of the body (obtained via rapid autopsy) to identify novel changes that may offer therapeutic insight. In addition, the University of Pittsburgh is the largest contributor of tissue to The Cancer Genome Atlas (TCGA), and many results are validated in these index cases.