Investigations on Aberrant Glycosylation of Glycosphingolipids in Colorectal Cancer Tissues Using Liquid Chromatography and Matrix-Assisted Laser Desorption Time-of-Flight Mass Spectrometry (MALDI-TOF-MS)

Stephanie Holst,Kathrin Stavenhagen,Crina I.A Balog,Carolien A.M Koeleman,Liam M Mcdonnell,Oleg A Mayboroda,Aswin Verhoeven,Wilma E Mesker,Rob A.E.M Tollenaar,André M Deelder,Manfred Wuhrer

doi:10.1074/mcp.m113.030387

Stephanie Holst, Kathrin Stavenhagen + Show 9 more

Open Access

https://doi.org/10.1074/mcp.m113.030387

Copy DOI

Abstract

Cancer is a leading cause of death and alterations of glycosylation are characteristic features of malignant cells. Colorectal cancer is one of the most common cancers and its exact causes and biology are not yet well understood. Here, we compared glycosylation profiles of colorectal tumor tissues and corresponding control tissues of 13 colorectal cancer patients to contribute to the understanding of this cancer. Using MALDI-TOF(/TOF)-MS and 2-dimensional LC-MS/MS we characterized enzymatically released and 2-aminobenzoic acid labeled glycans from glycosphingolipids. Multivariate data analysis revealed significant differences between tumor and corresponding control tissues. Main discriminators were obtained, which represent the overall alteration in glycosylation of glycosphingolipids during colorectal cancer progression, and these were found to be characterized by (1) increased fucosylation, (2) decreased acetylation, (3) decreased sulfation, (4) reduced expression of globo-type glycans, as well as (5) disialyl gangliosides. The findings of our current research confirm former reports, and in addition expand the knowledge of glycosphingolipid glycosylation in colorectal cancer by revealing new glycans with discriminative power and characteristic, cancer-associated glycosylation alterations. The obtained discriminating glycans can contribute to progress the discovery of biomarkers to improve diagnostics and patient treatment.

Highlights

Worldwide, cancer is a leading cause of death
Glycosylation is involved in many biological processes and especially its functional role in cellular interaction with respect to adhesion, cell growth, and signaling is prone to be affected in cancer progression, invasion, and metastasis [9]
Profiling of GSL-Glycans from Colorectal Cancer Tissues— GSL-glycans from tumor tissues of 13 patients diagnosed with colorectal cancer were analyzed and compared with their corresponding control tissues taken from the same resection material

Summary

Introduction

Cancer is a leading cause of death. With estimated 1.2 million diagnoses in 2008, colorectal cancer is the third most common cancer in the world and the fourth most common cause of death with an annual mortality of ϳ600 000. The heterogeneity of colorectal cancer at the molecular level— caused by accumulation of multiple genetic changes—may be one of the main reasons for this variability [5]. Genetic factors such as instabilities, and expression levels [6] can explain part of the cancer biology, but glycomics is gaining importance to complement the overall picture as aberrant glycosylation of proteins and lipids has been shown to be correlated with disease and malignancy [7, 8]. Glycosylation is involved in many biological processes and especially its functional role in cellular interaction with respect to adhesion, cell growth, and signaling is prone to be affected in cancer progression, invasion, and metastasis [9]. The abbreviations used are: GSL-glycan, glycosphingolipid derived glycan; AA, 2-aminobenzoic acid; Ac, acetyl group; Fuc, F, fucose; Hex, H, hexose; HILIC, hydrophilic interaction liquid chroma-

Methods

Results

Conclusion