Glycobiology Advance Access first published online on February 9, 2007
This version published online on February 19, 2007
Glycobiology, doi:10.1093/glycob/cwm012
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Human gliosarcoma-associated ganglioside composition is complex and distinctive as evidenced by high-performance mass spectrometric determination and structural characterization>
eljka Vukeli
2
454
2 Department of Chemistry and Biochemistry, Faculty of Medicine, University of Zagreb, 
alata 3, 10000 Zagreb, Croatia
3 Croatian Institute for Brain Research, Faculty of Medicine, University of Zagreb, alata 12, 10000 Zagreb, Croatia
4 Institute for Medical Physics and Biophysics, University of Münster, Robert-Koch-Str. 31, D-48149 Münster, Germany
5 Department of Neurology, Clinical Hospital Dubrava, Avenija Gojka u
ka bb, 10000 Zagreb, Croatia
6 Advion BioSciences, Ltd., Rowan House, 26-28 Queens Road, Hethersett Norwich Norfolk, NR9 3DB, United Kingdom
7 Department of Chemistry and Biology, University of Arad, Revolutiei Blvd. 1, RO-310139, Arad, Romania
8 Mass Spectrometry Laboratory, National Institute for Research and Development in Electrochemistry and Condensed Matter, Plautius Andronescu Str.1, 300224, Timisoara, Romania
1 To whom correspondence should be addressed; e-mail: zamfir{at}uav.ro; tel: +40-356-437974; fax: +40-256-204698
Received on December 5, 2006; revised on January 29, 2007; accepted on January 30, 2007
Gangliosides (GGs), involved in malignant alteration and tumour progression/invasiveness, are considered as tumour biomarkers or therapeutic targets. Here we describe the first systematic GG composition characterization in human gliosarcoma vs. normal brain tissue using our recently developed mass spectrometry (MS) methods, based on nanoelectrospray (nanoESI), Fourier-transform ion cyclotron resonance (FT-ICR) and chip nanoESI quadrupole time-of-flight (QTOF), complemented by thin-layer chromatographic (TLC) analysis and quantification. Combined MS enabled detection and structural assignment of 73 distinct GG species: many more than reported so far for investigated gliomas. Apart from the 7.4-times lower total GG content, gliosarcoma contained all major brain-associated species, however in very altered proportions, exhibiting a highly distinctive pattern: GD3 (48.9%) > GD1a/nLD1 > GD2/GT3 > GM3 > GT1b > GM2 > GM1a/GM1b/nLM1 > LM1 > GD1b > GQ1b. MS also revealed abundant O-Ac-GD3; its sequencing provided structural evidence to postulate a novel O-Ac-GD3 isomer O-acetylated at the inner Neu5Ac-residue, previously not structurally confirmed. The high sensitivity and mass accuracy permitted the assignment of unusual minor species: GM4, Hex-HexNAc-nLM1, Gal-GD1, Fuc-GT1, GalNAc-GT1, O-Ac-GM3, di-O-Ac-GD3, and O-Ac-GT3, not previously reported as glioma-associated. The gliosarcoma-expressed GA2 might represent a marker distinguishing astrocytic from oligodendroglial tumours. This is, to our knowledge, so far the most complete ganglioside composition characterization of certain glioma, which demonstrates that our MS-based approach could provide essential structural information relevant to glycosphingolipid role(s) in brain tumour biology, differential diagnosis/prognosis and novel treatment concepts.
Key words: biomarkers and target molecules / ganglioside structures / gliosarcoma ganglioside composition / high-performance mass spectrometry / novel O-acetylated GD3 isomer
Two author names have been corrected.