Improving the early detection of cancer has proven to be one of the most effective ways of reducing cancer mortality. Most patients with pancreatic cancer do not develop symptoms until after the disease has spread to other organs. Accurate laboratory tests that could detect pancreatic cancer while it is still curable would be of great benefit to patients. The opportunity to cure individuals at high-risk of developing pancreatic cancer is suggested by the results of recent screening studies showing that imaging the pancreas with endoscopic ultrasound and CT, can detect and cure individuals who have precursors to invasive pancreatic cancer. Screening such individuals with imaging alone is costly and therefore not an optimal early detection strategy. Thus, there is a need for accurate molecular markers that indicate the presence of microscopic pancreatic neoplasia that is invisible to imaging as a way to better define pancreatic neoplasia risk and burden. This project has identified several promising markers of pancreatic cancer including the serum protein marker MIC- 1 and methylated DMA markers for pancreatic juice analysis. We have also begun evaluating the utility of using methylated DNA markers along with endoscopic ultrasound to screen individuals at high risk of developing pancreatic cancer. To build on these successes, we will utilize tissues of Core 2 and the CAPS (Cancer of the Pancreas) screening trials to translate the discoveries of this project and Project 3C (formerly 2A) to patient care, to provide a scientific basis for approaches taken in Projects 3A and Core 3, and to adopt new technology developed in Project 1A. To achieve our goal of improving the diagnosis of early pancreatic neoplasia we will investigate three rational marker approaches. First, we propose to use microarrays to identify a more specific panel of DNA methylation markers and test their ability to identify individuals with early invasive pancreatic cancer and its precursors. Thus, we propose for Specific Aim #1: To detect and characterize genes specifically methylated in early-stage invasive pancreatic cancer and its precursors and to develop a diagnostic marker panel for pancreatic fluid analysis. Second, the detection of cancer using molecular markers depends as much on accurate assays as on the markers being assayed. A novel method has been developed for quantifying low-abundance mutations in secondary fluids termed "BEAMing" (Beads, Emulsion, Amplification and Magnetics). We will adapt the BEAMing method to detecting circulating DNA methylation alterations that arise in invasive pancreatic cancer and its precursors. Thus, we propose for Aim #2: To develop methods to detect methylated DNA and evaluate their utility as indicators of early pancreatic cancer and its precursors. Third, we will continue to identify and evaluate promising serum protein markers of pancreatic cancer and will evaluate the utility of serum markers to identify pre-invasive disease neoplasia. Thus, we propose for Aim #3: To identify protein markers of early pancreatic cancer and its precursors.