Changes of serum glycome in patients suffering from ovarian cancer.

Abstract

5047 Background: Protein glycosylation plays an important role in many biological processes. Most human serum proteins, with the exception of albumin, are glycosylated. Glycosylation is known to be altered with development of diseases such as cancer. In the case of ovarian cancer, tumor markers among them CA-125 that are clinically used are known to have poor specificity. In addition, they fail to detect the disease at an early stage. Therefore, better biomarkers are needed. The aim of the present research work is to identify new potential glycan biomarkers by analyzing the serum N-glycome of patients suffering from ovarian cancer Methods: Serum was collected from 67 patients as well as from 33 healthy age-matching women. N-glycans were released from 10 ul serum by PNGase F digestion, permethylated and subsequently analyzed by means of MALDI-TOF mass spectrometry. The SPSS software was used for the statistical analysis. Results: The N-glycome of patients was found to have more fucosylated structures, especially in tri- and tetraantennary sialylated glycans. The PCA analysis indicates that there are significant differences between the glycome of ovarian cancer patients in all stages of the disease and the glycome of healthy controls. We identified 14 potential structures that were divided in two categories, one of monofucosylated structures with high antennarity (sensitivity 94%, specificity 97%) and one containing high-mannose structures and an asialylated structures (sensitivity 97%, specificity 97%). Conclusions: Our study is the first trial to identify major differences between ovarian cancer sera and control sera, which could potentially be used in the future as biomarkers.