Project Summary/Abstract We propose to build and utilize a unique repository of biospecimens that are focused on early pancreatic lesions by assembling a unique and robust collection of early lesions and blood samples from patients at risk and those with lesions representing early stages of pancreatic cancer, matched sets of tumors and metastasis and control tissues from the same patients, and in many cases longitudinally obtained blood samples from the same patients. We will include longitudinally obtained samples from patients at risk for developing pancreatic cancer that go on to develop pancreatic cancer, including patients with cystic lesions, chronic pancreatitis, and adult onset diabetes. This unique resource will be used to identify and characterize biomarkers that develop during the progression from premalignant lesions to primary tumors, and to evaluate blood samples from these patients for the presence of biomarkers at both early and late stages of disease progression. Both the biospecimens and candidate biomarkers will be available for collaborative studies within the Pancreatic Cancer Detection Consortium. Specific 1. We will establish a comprehensive collection of tissues (fixed, frozen and living as organoids) representing the spectrum of premalignant to malignant and metastatic lesions that occur within individual patients obtained at autopsy and at surgery, and develop a collection of longitudinally obtained blood and tissue specimens from patients at risk for pancreatic cancer and that develop pancreatic cancer. Specific Aim 2. We will evaluate 15 novel glycoprotein biomarkers of pancreatic cancer progression in human tissue samples containing cell types that represent the progression of pancreatic cancer from early premalignant lesions to primary and metastatic cancer. Specific Aim 3. We will evaluate the expression of 15 novel glycoprotein biomarkers of pancreatic cancer progression in longitudinal samples serum and plasma of patients that develop pancreatic cancer, and compare these to longitudinal samples of appropriate patients with benign diseases. Specific Aim 4. Discover cell surface antigens specific to the malignant state by applying phage- display approaches to human pancreatic organoids. Specific Aim 5. To evaluate and discover exosome-based biomarkers of pancreatic cancer by using an unbiased proteomic analysis of exosomal cargo derived from patients with early stage pancreatic lesions (PanIN3 eand early stage tumors) to develop a panel of markers that can accurately predict the progression of these lesions towards pancreatic cancer.