Jules Griffin

The metabolomics standards initiative (MSI)

In 2005, the Metabolomics Standards Initiative has been formed. An outline and general introduction is provided to inform about the history, structure, working plan and intentions of this initiative. Comments on any of the suggested minimal reporting standards are welcome to be sent to the open email list Msi-workgroups-feedback@lists.sourceforge.net

Hypoxic Regulation of Hand1 Controls the Fetal-Neonatal Switch in Cardiac Metabolism

This study reveals a novel pathway that responds to hypoxia and modulates energy metabolism by cardiomyocytes in the mouse heart, thereby determining oxygen consumption.

Metabolomics-guided insights on bariatric surgery versus behavioral interventions for weight loss

To review the metabolomic studies carried out so far to identify metabolic markers associated with surgical and dietary treatments for weight loss in subjects with obesity.

Association between plasma phospholipid saturated fatty acids and metabolic markers of lipid, hepatic, inflammation and glycaemic pathways in eight European countries : A cross-sectional analysis in the EPIC-InterAct study

BackgroundAccumulating evidence suggests that individual circulating saturated fatty acids (SFAs) are heterogeneous in their associations with cardio-metabolic diseases, but evidence about associations of SFAs with metabolic markers of different pathogenic pathways is limited. We aimed to examine the associations between plasma phospholipid SFAs and the metabolic markers of lipid, hepatic, glycaemic and inflammation pathways.MethodsWe measured nine individual plasma phospholipid SFAs and derived three SFA groups (odd-chain: C15:0 + C17:0, even-chain: C14:0 + C16:0 + C18:0, and very-long-chain: C20:0 + C22:0 + C23:0 + C24:0) in individuals from the subcohort of the European Prospective Investigation into Cancer and Nutrition (EPIC)-InterAct case-cohort study across eight European countries. Using linear regression in 15,919 subcohort members, adjusted for potential confounders and corrected for multiple testing, we examined cross-sectional associations of SFAs with 13 metabolic markers. Multiplicative interactions of the three SFA groups with pre-specified factors, including body mass index (BMI) and alcohol consumption, were tested.ResultsHigher levels of odd-chain SFA group were associated with lower levels of major lipids (total cholesterol (TC), triglycerides, apolipoprotein A-1 (ApoA1), apolipoprotein B (ApoB)) and hepatic markers (alanine transaminase (ALT), aspartate transaminase (AST), gamma-glutamyl transferase (GGT)). Higher even-chain SFA group levels were associated with higher levels of low-density lipoprotein cholesterol (LDL-C), TC/high-density lipoprotein cholesterol (HDL-C) ratio, triglycerides, ApoB, ApoB/A1 ratio, ALT, AST, GGT and CRP, and lower levels of HDL-C and ApoA1. Very-long-chain SFA group levels showed inverse associations with triglycerides, ApoA1 and GGT, and positive associations with TC, LDL-C, TC/HDL-C, ApoB and ApoB/A1. Associations were generally stronger at higher levels of BMI or alcohol consumption.ConclusionsSubtypes of SFAs are associated in a differential way with metabolic markers of lipid metabolism, liver function and chronic inflammation, suggesting that odd-chain SFAs are associated with lower metabolic risk and even-chain SFAs with adverse metabolic risk, whereas mixed findings were obtained for very-long-chain SFAs. The clinical and biochemical implications of these findings may vary by adiposity and alcohol intake.

Abstract 5573: GC-TOF mass spectroscopy reveals strong dependence of breast cancer metabolome on estrogene receptor, but not on HER2 status

Breast cancer is a biologically inhomogeneous disease that has been extensively studied using molecular high-throughput platforms like microarrays. Molecular methods have been shown to be useful for therapy selection, prediction of disease outcome or complications such as metastases. Worldwide, immunhistological determination of estrogene receptor (ER) and HER2 status is part of the everyday routine diagnostics. A bunch of new biomarkers and biomarker signatures is currently under development and expected to further individualize and improve breast cancer treatment. Here, we present results of a GC-TOF mass spectrometry (GC-MS) metabolite study conducted by the METACancer consortium. In this project, 275 breast cancer tissues collected as fresh-frozen samples in the METACancer tumor bank were analyzed using GC-MS. Prior to metabolic profiling, tumors were divided in a training (187 tumors) and a validation cohort (88 tumors) with comparable clinicopathological characteristics. Both cohorts were profiled at the Fiehn lab (UC Davis, CA), the training cohort at the end of 2008, the validation cohort at the beginning of 2009. Analysis of the training cohort led to the identification of 468 metabolites that are abundant in breast cancer tissues. 161 out of these could be mapped to known chemical structures and metabolite names. Metabolite-by-metabolite analysis of the training cohort revealed 70 metabolites with significantly (p Next, we asked if the tumor cells exhibit metabolite patterns that are specific for ER status. To this end, a metabolic index (MI) was constructed as linear combination of 15 metabolites. The MI was constructed and optimized using only tumors of the training cohort. ROC analysis showed an excellent perfomance of the MI for prediction of the ER status in the training cohort (AUC = 0.91, leave-one-out cross-validation). Validation of the MI in the validation cohort affirmed the excellent performance (AUC = 0.97). A similar approach for prediction of the HER2 status failed (AUC not significantly better than 0.50). In this project, we have shown that metabolic profiling of fresh-frozen breast cancer samples with GC-MS is feasible. Interestingly, we detected a strong dependence of the metabolite patterns on ER status, but no dependence on HER2 status. Analysis of the changes in metabolic pathways between ER+ and ER- breast cancers may contribute to a better understanding of estrogen driven tumor growth. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5573.

Metabolic adaptations to targeted therapy in FLT3 mutated acute myeloid leukaemia

Abstract Background Acute myeloid leukaemia has a dismal outlook. FLT3 tyrosine kinase (TK) activating mutations ( FLT3 mut) are present in 30% of cases and are predictive of a worse outcome. Although metabolic reprogramming has been recognised as a hallmark of cancer cells, little is known about its role in acute myeloid leukaemia. Published gene expression datasets show that glycolytic, citric acid cycle, and oxidative phosphorylation genes are upregulated in FLT3 mut patient samples at diagnosis. We aimed to study metabolic changes in FLT3 mut disease upon targeted inhibition of its TK activity in an attempt to unveil novel therapeutic vulnerabilities. Methods Liquid chromatography coupled to mass spectrometry, using stable isotope-based carbon flux tracing, and an extracellular flux analyser (Seahorse, Agilent Technologies, Santa Clara, CA, USA) were used to assess metabolic changes in FLT3 mut human and murine cells after FLT3 TK inhibition by the specific inhibitor AC220. Gene expression changes were measured in the same conditions by RNA sequencing. Fluorescence-activated cell sorting was used to measure changes in viability and reactive oxygen species after inhibition of TK activity in various culture conditions. Findings We confirmed in both human and murine cells that FLT3 mut cells displayed an increased glycolytic (maximal glycolytic capacity, extracellular acidification rate of 80·64 mpH/min in FLT3 mut vs 59·09 in FLT3 wildtype, p FLT3 mut vs 180·9 in FLT3 wildtype, p − 13 C]glutamine suggested that glutamine was diverted to glutathione production upon AC220 treatment. FLT3 mut cells displayed a large increase in concentration of reactive oxygen species upon AC220 treatment when grown in the absence of glutamine (fold increase of reactive oxygen species normalised to untreated cells 4·59 without glutamine vs 2·74 with glutamine, p vs 62·5% with glutamine, p Interpretation Our data suggest that FLT3 mut acute myeloid leukaemia cells have increased respiratory and glycolytic capacity that is reversed by TK inhibition. Upon AC220 treatment glutamine metabolism becomes a metabolic dependency of FLT3 mut disease, as glutamine is channelled towards glutathione production and reactive oxygen species detoxification, and protects them from cell death. This process could be exploited therapeutically by a combination of glutaminolysis or glutathione biosynthesis inhibitors with FLT3 TK inhibitors. Funding Wellcome Trust.

Abstract 4806: Association of changes in 4-aminobutyrate aminotransferase (ABAT) and beta-alanine metabolism with breast cancer and the more aggressive estrogen receptor negative subtype

Metabolic changes are the final answer of the cell to environmental or genetic changes. While gene expression in breast cancer has extensively been studied, studies on the breast cancer metabolome and its correlation to transcriptional changes are rare. Therefore, a combined metabolomics and transcriptomics study was carried out by the METAcancer consortium. In this project, 275 breast cancer tissues collected as fresh-frozen samples in the METAcancer tumor bank were analyzed using gas chromatography combined with time of flight mass spectrometry (GC-TOF-MS). Out of these, 156 tumor samples were transcriptionally profiled using whole genome DASL. Before, we identified 10 increased and 9 decreased metabolites in the more aggressive estrogen receptor negative (ER-) compared to the estrogen receptor positive (ER+) breast cancer (poster #5573, AACR Annual Meeting 2010). Among these changes, the increase of beta-alanine (fold change = 2.4, p = 1.7E-20) was the strongest and most significant alteration. Comparing breast cancer and normal tissues, beta-alanine turned out to be strongly increased in the cancer tissues (fold change = 2.6, p = 1.1E-34). Using the Kyoto Encyclopedia of Genes and Genomes (KEGG) we identified 135 enzymes that catalyze reactions of the 19 regulated metabolites. These enzymes were subjected to correlation analysis with their substrates and products. As most significant result, a negative relationship between 4-aminobutyrate aminotransferase (ABAT) expression and beta-alanine concentration was detected (Pearson correlation = –0.62, p = 1.1E-17). ABAT was significantly down-regulated in the more aggressive ER- subtype (fold change = –1.9, p = 1.6E-08). The differential expression of ABAT was confirmed in three publicly available breast cancer microarray data sets. The effect of ABAT inhibition was investigated in estrogen receptor positive MCF-7 and triple-negative MDA-MB-231 breast cancer cells. In both cell lines, treatment with vigabatrin, a small molecule that binds irreversibly to ABAT and inhibits the enzymatic activity, increased proliferation. In summary, we detected an accumulation of beta-alanine in breast cancer and an increase of beta-alanine and a down-regulation of ABAT in the more aggressive ER- subtype. The regulation of beta-alanine metabolism that underlies these changes is currently investigated in cell culture models. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4806. doi:1538-7445.AM2012-4806