Profiling and sequence analysis of gangliosides in human astrocytoma by high-resolution mass spectrometry

Abstract

In this preliminary investigation, a low-grade astrocytoma (AcT) is investigated by high-resolution (HR) mass spectrometry (MS) aiming at characterization of gangliosides with potential biomarker value. The research was conducted towards a comparative mapping of ganglioside expression in AcT, its surrounding tissue (ST) and a normal control brain tissue (NT). HR MS was conducted in the negative ion mode nanoelectrospray ionization (nanoESI). Fragmentation analysis was carried out by collision-induced dissociation (CID) MS(2)-MS(4.) Due to the high resolving power and mass accuracy, by comparative mapping of the ganglioside extracts from AcT, ST and NT, under identical conditions, 37 different species in AcT, 40 in ST and 56 in NT were identified. AcT and ST were found to contain 18 identical ganglioside components. Among all three specimens, ST extract presented the highest levels of sialylation, fucosylation and acetylation, a feature which might be correlated to the tumor expansion in the adjacent brain area. MS mapping indicated also that AcT, ST and NT share one doubly deprotonated molecule at m/z 1063.31, attributable to GT1(d18:1/18:0) or GT1(d18:0/18:1). CID MS(2)-MS(4) on these particular ions detected in AcT and ST provided data supporting GT1c isomer in the investigated astrocytoma tissue. Our results show that HR MS has a remarkable potential in brain cancer research for the determination of tumor-associated markers and for their structural determination.

A monophasic extraction strategy for the simultaneous lipidome analysis of polar and nonpolar retina lipids

“…Reconstituted retina lipid extracts were centrifuged at 2,000 g to remove any residual particulates, then transferred to 2.0 ml glass vials and stored at Ϫ 80°C until further use. Using this method, a total of three replicate polar upper phase and three replicate nonpolar lower phase retina lipid extracts were obtained, Numerous lipidomic methods for the characterization of gangliosides obtained from polar lipid extracts have been developed based on LC-MS platforms ( 23,49 ) as well as direct infusion by nESI ( 50,51 ), including the use of the highresolution/accurate mass Orbitrap platform ( 52 ). However, all ganglioside analysis methods reported to date have involved either the initial extraction and specifi c enrichment of gangliosides at the exclusion of other lipid classes by using variants of the classical Svennerholm ganglioside extraction method ( 17 ) or via the fractionation of total lipid extracts by chromatographic separation.…”

A novel direct spray-from-tissue ionization method for mass spectrometric analysis of human brain tumors

“…One of the approaches for such differentiation is by comparing their lipid profiles [12]. For example, gangliosides are used to differentiate astrocytoma tissue from the surrounding tissues and normal control brain tissues [13,14], or lipid profiles are used for the determination of tumor borders [15,16].…”

Plasmatic Ganglioside Profile and Age-Related Macular Degeneration: A Case-Control Study

“…However, they did not find any molecular species that could be used as a biomarker of the disease. The last profiling study was conducted on human astrocytoma GGs using high-resolution MS [27]. The authors detected 30 molecular species, distributed between different GG classes, in tumor tissues that were absent from normal brain tissue.…”