Serum N-glycans are promising biomarkers for systemic disease states. Better understanding of the serum N-glycome of patients with resectable periampullary adenocarcinoma may identify novel prognostic markers for this disease. Serum N-glycans in 70 patients with resectable periampullary adenocarcinoma, 15 patients with benign periampullary tumor, and 129 healthy individuals were quantified using ultra performance liquid chromatography. High-sensitivity C-reactive protein (hsCRP) was analyzed for all samples using an immunoturbidimetric method. The N-glycome was compared to clinical and histopathological data, and to the acute phase response as measured by hsCRP. Whole-genome tumor tissue mRNA expression data were used for correlation and enrichment analysis to investigate underlying biological processes giving rise to changes in the serum N-glycome. Significant changes were found in the serum N-glycome of patients with periampullary adenocarcinoma (n = 70) compared to healthy individuals (n = 129). No significant differences were found between patients with benign (n = 15) and malignant periampullary tumors (n = 70). Many alterations in the N-glycome correlated with systemic acute phase response as measured by hsCRP. Enrichment analysis indicated that immunologic pathways of the cancer microenvironment correlate with specific features of the serum N-glycome. Certain glycans were associated with poor overall and disease free survival in patients with pancreatobiliary type of periampullary adenocarcinoma. Our study supports the hypothesis that certain factors secreted by the tumor affect liver and plasma cells to orchestrate the changes in the serum N-glycome observed. The serum N-glycome could potentially reflect modified phenotypes of the host and/or tumor microenvironment. The prognostic impact of the serum N-glycome should be evaluated in larger, prospective studies.
Keywords: N-glycan; acute phase response; inflammation; pancreatic cancer; pancreatitis; periampullary adenocarcinoma.