The Analysis of Human Serum N-Glycosylation in Patients with Primary and Metastatic Brain Tumors
Abstract: The identification of patients with different brain tumors is solely built on imaging diagnostics,
indicating the need for novel methods to facilitate disease recognition. Glycosylation is a
chemical modification of proteins, reportedly altered in several inflammatory and malignant diseases,
providing a potential alternative route for disease detection. In this paper, we report the quantitative
analysis of serum N-glycosylation of patients diagnosed with primary and metastatic brain tumors.
PNGase-F-digested and procainamide-labeled serum glycans were purified by magnetic nanoparticles,
followed by quantitative liquid chromatographic analysis. The glycan structures were identified
by the combination of single quad mass spectrometric detection and exoglycosidase digestions.
Linear discriminant analysis provided a clear separation of different disease groups and healthy
controls based on their N-glycome pattern. Altered distribution of biantennary neutral, sialylated
but nonfucosylated, and sialylated–fucosylated structures were found to be the most significant
changes. Our results demonstrate that serum glycosylation monitoring could improve the detection
of malignancy.