Ovarian cancer is a silent killer with few early symptoms and advanced disease often present at the time of diagnosis. This cancer is the most lethal of all gynecologic malignancies with over 20,000 new cases diagnosed each year. The 5 year survival rates for ovarian cancer dramatically improve when the disease is diagnosed at an earlier stage. Therefore, the long term goal of the Glycomics Laboratory for the Development of Ovarian Cancer Biomarkers is to apply the most advanced technologies toward the goal of identifying glycoprotein and glycan markers that can detect ovarian cancer early. We are a multidisciplinary team with expertise in cancer biology, glycomics, glycan array analysis, and translational glycoimmunology from investigators at the University of Arkansas for Medical Sciences (UAMS), the Complex Carbohydrate Research Center (CCRC) at the University of Georgia, and the Harvard Medical School Center for Glycoscience at Harvard University. The investigators at UAMS specialize in biomarker discovery using glycomic methods and functional studies of glycosyltransferase enzymes in ovarian cancer progression, the co-investigators at the CCRC specialize in the mass spectrometry identification of O-linked glycans present on the Notch receptor and the functional analysis of these glycans in Notch activation, and the co-investigators at Harvard specialize in the development of antibodies binding to tumor-specific glycans and the development of glycopeptide arrays. The aims of this application are (1) To develop and validate N-linked and O-linked glycoforms for the detection of ovarian cancer and (2) To discover and develop glycosylphosphatidylinositol (GPI) anchored protein glycoforms and GPI anchor binding proteins for the detection of ovarian cancer.