Project description:Mass spectrometry raw data repositories, including Metabolomics Workbench and MetaboLights, have contributed to increased transparency in metabolomics studies and the discovery of novel insights in biology by reanalysis with updated computational metabolomics tools. Herein, we reanalyzed the previously published lipidomics data from nine algal species, resulting in the annotation of 1437 lipids achieving a 40% increase in annotation compared to the previous results. Specifically, diacylglyceryl-carboxyhydroxy-methylcholine (DGCC) in Pavlova lutheri and Pleurochrysis carterae, glucuronosyldiacylglycerol (GlcADG) in Euglena gracilis, and P. carterae, phosphatidylmethanol (PMeOH) in E. gracilis, and several oxidized phospholipids (oxidized phosphatidylcholine, OxPC; phosphatidylethanolamine, OxPE; phosphatidylglycerol, OxPG; phosphatidylinositol, OxPI) in Chlorella variabilis were newly characterized with the enriched lipid spectral databases. Moreover, we integrated the data from untargeted and targeted analyses from data independent tandem mass spectrometry (DIA-MS/MS) acquisition, specifically the sequential window acquisition of all theoretical fragment-ion MS/MS (SWATH-MS/MS) spectra, to increase the lipidomic annotation coverage. After the creation of a global library of precursor and diagnostic ions of lipids by the MS-DIAL untargeted analysis, the co-eluted DIA-MS/MS spectra were resolved in MRMPROBS targeted analysis by tracing the specific product ions involved in acyl chain compositions. Our results indicated that the metabolite quantifications based on DIA-MS/MS chromatograms were somewhat inferior to the MS1-centric quantifications, while the annotation coverage outperformed those of the untargeted analysis of the data dependent and DIA-MS/MS data. Consequently, integrated analyses of untargeted and targeted approaches are necessary to extract the maximum amount of metabolome information, and our results showcase the value of data repositories for the discovery of novel insights in lipid biology.
Project description:Purpose: Gut microbiota is associated with the progression of brain tumor. However, the alterations in the gut microbiota during glioma growth and temozolomide (TMZ) therapy remains to be understood. Methods: C57BL/6 male mice were implanted with GL261 glioma cells. TMZ/sodium carboxymethyl cellulose (SCC) was administered by gavage for five consecutive days (from 8 to 12 days after implantation). Fecal samples were collected before (T0) and on days 7 (T1), 14 (T2), and 28 (T3) after implantation. The gut microbiota was analyzed using 16S ribosomal DNA sequencing followed by absolute and relative quantitation analyses. Results: Nineteen genera were altered during glioma progression with the most dramatic changes in Firmicutes and Bacteroidetes phyla. During glioma growth, Lactobacillus abundance decreased at the earlier stage of glioma development (T1), and then gradually increased (T2, T3); Intestinimonas abundance exhibited a persistent increase; Anaerotruncus showed a transient increase and then a subsequent decrease. Twenty genera altered following TMZ treatment. The enrichment of Akkermansia and Bifidobacterium was observed only at the early stage following TMZ treatment (T2), but not at the later stage (T3). Additionally, the decrease of Anaerotruncus was slighter in TMZ group at T3 comparing to the vehicle group. The abundance of Intestinimonas increased constantly during the progression of glioma, but was unaffected by TMZ. Conclusions: Glioma development and progression resulted in altered gut microbiota. TMZ reversed the decrease of Anaerotruncus in glioma at T3, and increased the abundance of Bifidobacterium with no influence on the increase of Intestinimonas. Short-term and long-term effects of TMZ treatment on the bacterial communities may be differential. This study will improve understanding the role of gut microbiota in glioma, and help develop gut microbiota as a potential therapeutic target.
Project description:Comparison of treatment sensitive GSC clones (TSGC) with treatment resistant GSC clones (TRGC). We used microarrays to identify molecular signatures of TRGC (upregulated genes). We used radiation treatment (RT) or RT plus TMZ to select treatment resistant GSC clones (TRGC)
Project description:Glioblastoma (GBM) is the most common primary brain tumor in adults with a median survival of 11-12 months. Standard therapy consists of radiotherapy (RT) plus chemotherapy with Temozolomide (TMZ), and no alternative treatment is available. We assessed changes in tumor microenvironment (TME) after RT associated with TMZ and metformin (MET) in a syngenic murine GBM model using single-cell RNA-sequencing (scRNA-seq). RT induced an enrichment of GO annotation related with cell cycle, translation and ribosome biogenesis in all tumor clusters, except the radio resistant one where an increase in the inflammatory phenotype was observed. Resident GAM were reduced after RT alone and differentially modulated by RT-drug combinations. After RT alone, we detected an increase in GAM markers and a downregulation of glycolytic metabolism in both microglial and peripheral macrophage subclusters. Association of TMZ increased the pro-inflammatory phenotype of some GAM clusters in comparison to RT. A different signature was observed for the TMZ-MET association but limited to peripheral infiltrating GAM.
Project description:Temozolomide (TMZ) resistance may contribute to the treatment failure in patients with glioblastoma (GBM). Hence, understanding the underlying mechanisms and developing effective strategies against TMZ resistance are highly desired in the clinic. long non-coding RNAs (lncRNAs) have emerged as new regulatory molecules with diverse functions in biological processes and been deregulated in many pathologies, involved in the therapeutic resistance. It is urgent to elucidate the underlying lncRNA-based mechanisms of TMZ resistance in GBM patients.
Project description:The discovery of long non-coding RNAs (lncRNAs) has improved the understanding of development and progression in various cancer sub-types. However, the role of lncRNAs in temozolomide (TMZ) resistance in glioblastoma (GBM) remains largely undefined. In this present study, the differential expression of lncRNAs were identified between U87 and U87TR (TMZ-resistant) cells and to find potential therapeutic targets of GBM for improving the survival of patients.
Project description:For the comparison of 6BG/TMZ with control sample, the predominant annotation among the upregulated genes is M-bM-^@M-^XapoptosisM-bM-^@M-^Y. The majority of the downregulated genes is assigned to heat shock proteins and proteins which bind unfolded proteins. To look at early changes in gene expression, primary human myeloid precursor cells (40 x 10^6 per sample) derived from 3 pooled CD34+ products were treated for 18 hours with control (vehicle), 6BG, TMZ, or 6BG/TMZ and cell pellets flash frozen. Total RNA were isolated at Miltenyi Biotec (Cologne, Germany) and bioinformatics analysis of four microarray datasets was performed by their Bioinformatics Group. The direct comparisons were: 6BG/TMZ vs Control, TMZ vs 6BG, 6BG/TMZ vs 6BG, 6BG/TMZ vs TMZ. A two-dye competitive hybridization of mRNAs derived from differently treated human cells in comparison to a reference mRNA derived from cells which underwent a different treatment was conducted. After treatment with two different drugs or a combination of both drugs, respectively, RNA was extracted from the cells and hybridized against the corresponding reference mRNA. As microarray platform, the PIQORM-bM-^DM-" Cell Death Microarray with 494 probes was used.
Project description:Differential transcriptome analysis between control cells (U87MG), TMZ-resistant cells with continuous TMZ treatment (U87MG R50) and TMZ-resistant cells with interrupted treatment (U87MG OFF R50).