The objective of this proposed project is to develop and validate novel systems for efficient expression of cancer-related hUman glycosylated proteins. The availability of such systems will aid analysis of cancerrelated proteins, especially those of low abundance from bodily fluids, and accelerate the development of effective cancer diagnostics and therapeutics. Bacteria and yeast cells have been widely used for producing recombinant human proteins with ease and at low costs, but the lack of mammalian-like post-translation modifications limits their applications. Expression using mammalian cells typically relies on either transient transfection or stable cell line establishment, requiring either high reagent costs for large-scale production or long development time. The baculovirus expression vector systems (BEVS) using insect cells provide an alternative at lower cost and faster turnaround time to mammalian systems. The major drawback of using insect cells in some cases is that certain modifications such as glycosylation differ from mammalian cells, A complete system will be developed to utilize BEVS in both insect and mammalian cells with unique purification method and flexibility to produce glycosylated proteins. At least 10 such proteins will be produced in Phase I. These proteins will be analyzed by MASS and made available to the greater scientific community.