Integrated N- and O-Glycomics of Acute Myeloid Leukemia (AML) Cell Lines

Abstract

Acute myeloid leukemia (AML) is characterized by a dysregulated expansion of poorly differentiated myeloid cells. Although patients are usually treated effectively by chemotherapy, a high rate of relapsed or refractory disease poses a major hurdle in its treatment. Recently, several studies have proposed implications of protein glycosylation in the pathobiology of AML including chemoresistance. Accordingly, associations have been found between specific glycan epitopes and the outcome of the disease. To advance this poorly studied field, we performed an exploratory glycomics study characterizing 21 widely used AML cell lines. Exploiting the benefits of porous graphitized carbon chromatography coupled to tandem mass spectrometry (PGC nano-LC-MS2), we qualitatively and quantitatively profiled N- and O-linked glycans. AML cell lines exhibited distinct glycan fingerprints differing in relevant glycan traits correlating with their cellular phenotype as classified by the FAB system. By implementing transcriptomics data, specific glycosyltransferases and hematopoietic transcription factors were identified, which are candidate drivers of the glycan phenotype of these cells. In conclusion, we report the varying expression of glycan structures across a high number of AML cell lines, including those associated with poor prognosis, identified underlying glycosyltransferases and transcription factors, and provide insights into the regulation of the AML glycan repertoire.

Glycosphingolipid-Glycan Signatures of Acute Myeloid Leukemia Cell Lines Reflect Hematopoietic Differentiation

“…In addition, the finding of a previous study of increased Lewis A/X antigens on N - and O -glycome in the M2 and M5 subtypes is consistent with our current result. 5 In contrast, blood group H antigens were detected in cell lines originating from myelocytes/erythrocytes/monocytes. These H antigens are highly expressed in ML1 and ME1 (M4 subtype belonging to myeloblasts).…”

“…To confirm this, knockout, knockdown, and overexpression experiments targeting GATA2 in M6 cell lines assessing the effect on various glycoconjugates would be informative. 5 …”

“…Our data point toward a shared effect of certain TFs on different types of glycoconjugates, as GATA2 likewise shows positive correlation with the total levels of sialylation on N - and O -glycome in AML cell lines. 5 Meanwhile, erythrocyte/megakaryocyte-related TF GATA1 ( 57 ) has been found to be expressed at low levels in M3, M4, and M5 AML.…”

“… 4 A previous study investigated the N - and O -glycome of AML cell lines and explored the potential roles of relevant GTs and transcription factors (TFs) in the regulation of the glycan phenotype of the studied acute myeloid leukemia (AML) cell lines. 5 However, still little is known about the gene network that coordinates the expression of GSL-synthesizing enzymes. 1 , 6 …”

“…4 A previous study investigated the N-and O-glycome of AML cell lines and explored the potential roles of relevant GTs and transcription factors (TFs) in the regulation of the glycan phenotype of the studied acute myeloid leukemia (AML) cell lines. 5 However, still little is known about the gene network that coordinates the expression of GSL-synthesizing enzymes. 1,6 Alterations of glycosylation including changes of sialylation (α2,3/6/8-sialylation) and fucosylation (blood H antigens, Lewis antigens) have been described for various hematological malignancies for both glycoproteins and GSLs.…”