123rd General Meeting of the KCS

Type Oral Presentation
Area Oral Presentation of Young Analytical Chemists I
Room No. Room 202
Time THU 09:08-09:12
Code ANAL1.O-3
Subject Absolute Quantitation of Non-Human Glycan (Neu5Gc) in Human Biopsy Tissue by LC/MRM-MS
Authors Nari Seo, Myung Jin Oh, Hyun Joo An*
Graduate School of Analytical Science and Technolo, Chungnam National University, Korea
Abstract N-Glycolylneuraminic acid (Neu5Gc), which cannot be synthesized in human, is an immunogenic sugar of dietary source. Neu5Gc in blood and tissue metabolically promote a variety of cell-to-cell adhesion processes in inflammation and the immune response related to cancer, cardiovascular, and inflammatory diseases. Thus, Neu5Gc in human has been considered as the indication of inflammation-mediated diseases, and their level has attracted more attention for monitoring disease progression and/or response to therapy. Although several Neu5Gc quantitation methods have been proposed for disease marker, determination of the levels of Neu5Gc in individual human samples is still challenging because there are very low amounts of Neu5Gc (less than 0.01% of the total sialic acids). Here, we have developed the MRM-based assay for the first time to quantify Neu5Gc from one shot biopsy gastric tissues, proved that the amount of Neu5Gc was correlated with cancer. Gastric biopsy tissues of cancer patient (n=10) and healthy control (n=10) were obtained from Seoul National University Bundang Hospital in Korea. Each tissue (2-3 mg wet wt.) was chemically treated. Liberated Neu5Ac and Neu5Gc were chromatographically separated, then monitored by LC/MRM-MS. The quantitative calibration curve of Neu5Gc was linear over the range of 1.5 fmol/L to 1.5 μmol/L (103) and its correlation coefficient (r2) was >0.999. Neu5Gc was successfully quantified in all samples from gastric cancer patients and healthy controls, and the concentration of Neu5Gc was determined at fmol levels per one biopsy tissue. When compared to absolute abundances of Neu5Gc between controls and patients, expression levels in patient cohorts were 1.5 to 2-folds higher than those in the control group. These results could be supporting that the existence of Neu5Gc in human is linked to the disease. The developed strategies might be a new paradigm for a complement to glyco-based current cancer screening platform.
E-mail snr85@cnu.ac.kr