preparation-frozen-non-human-primate-fetal-islets-for-combined-single

Preparation of Frozen Non-Human Primate Fetal Islets for Combined Single Nuclei RNA-Sequencing and ATAC-Sequencing, and Bulk Metabolomics

One challenge in studies using tissue collected from multiple cohorts is avoiding batch effects when preparing for large-scale multi-omic experiments, ...

Human Metabolome Technologies (HMT) America

Metabolic reprogramming is a hallmark of cancer cells. In Waldenstrom Macroglobulinemia (WM), the infiltration of IgM-secreting lymphoplamacytic cells into the bone marrow (BM) could shift the homeostasis of proteins and metabolites towards a permissive niche for tumor growth. Here, we investigated whether alerted metabolic pathways contribute to the pathobiology of WM and whether the cytokine composition of the BM promotes such changes. Metabolomics analysis on WM patients and normal donors' serum samples revealed a total of 75 metabolites that were significantly altered between two groups. While these metabolites belonged to amino acids, glucose, glutathione and lipid metabolism pathways, the highest number of the differentially expressed metabolites belonged to glutathione metabolism. Proteomics analysis and immunohistochemical staining both confirmed the increased protein levels mediating glutathione metabolism, including GCLC, MT1X, QPCT and GPX3. Moreover, treatment with IL-6 and IL-21, cytokines that induce WM cell proliferation and IgM secretion, increased gene expression of the amino acid transporters mediating glutathione metabolism, including ASCT2, SLC7A11 and 4F2HC, indicating that cytokines in the WM BM could modulate glutathione metabolism. Glutathione synthesis inhibition using Buthionine sulphoximine (BSO) significantly reduced WM cells proliferation in vitro, accompanied with decreased NFκB-p65 and MAPK-p38 phosphorylation. Moreover, BSO treatment significantly reduced the tumor growth rate in a WM xenograft model, further highlighting the role of glutathione metabolism in promoting tumor growth and proliferation. In summary, our data highlight a central role for glutathione metabolism in WM pathobiology and indicate that intervening with the metabolic processes could be a potential therapy for WM patients.

Increased glutathione utilization augments tumor cell proliferation in Waldenstrom Macroglobulinemia.

The molecular events that modulate the progression of monoclonal gammopathy of undetermined significance of the immunoglobulin M class (IgM-MGUS) to Waldenstrom Macroglobulinemia (WM) are mostly unknown. We implemented comparative proteomics and metabolomics analyses on patient serum samples to identify differentially expressed molecules crucial to the progression from IgM-MGUS to WM. Our data identified altered lipid metabolism as a discriminating factor between MGUS, WM, and matched normal controls. Levels of many fatty acids, including polyunsaturated fatty acids and dicarboxylic acids, were significantly downregulated in WM sera when compared to MGUS. These reductions were associated with diminished 15-LOX and PPAR protein expression and increased 5-LOX and GPX4 expression in WM versus MGUS patients' samples. Furthermore, WM serum samples showed increased lipid peroxidation compared to MGUS. Treatment with IL-6 or TNFα, upstream regulators of differentially expressed proteins between MGUS and WM, increased lipid absorption and lipid peroxidation in WM cell lines. Knock-down of 15-LOX expression increased WM cell survival, an effect accompanied by increased 5-LOX and GPX4 expression. In summary, our data show that reduced fatty acid and lipid metabolite levels in the serum of the WM patients are associated with increased lipid peroxidation and that downregulation of 15-LOX increases the survival of WM cells. These data are highly significant in identifying the biomarkers of disease progression and designing targeted therapeutic intervention.

Progression from Monoclonal gammopathy of undetermined significance of the immunoglobulin M class (IgM-MGUS) to Waldenstrom Macroglobulinemia is associated with an alteration in lipid metabolism.

Article	Year
Increased glutathione utilization augments tumor cell proliferation in Waldenstrom Macroglobulinemia. Redox biology\| PubMed ID: 32763516	2020
Progression from Monoclonal gammopathy of undetermined significance of the immunoglobulin M class (IgM-MGUS) to Waldenstrom Macroglobulinemia is associated with an alteration in lipid metabo... Redox biology\| PubMed ID: 33690107	2021

Alex Buko

Biography

JoVE Journal Publications

Other Publications