Understanding the metabolic signatures of haematological cancers through an integrative multi-Omics approach

Haematological cancers are heterogenous diseases caused by a series of events which drive cells to uncontrolled proliferation and tumour progression. Nowadays, our understanding is that one hallmark of cancer cells is to reprogram their normal cellular metabolism to sustain their anabolic requirements for continuous cell growth and proliferation. Despite the remarkable progress in cancer metabolism, the exact mechanisms behind cancer metabolic reprogramming are not yet fully understood. The work presented in this thesis aims to provide novel biological insights into the metabolic reprogramming of haematological cancers and highlight potential metabolic vulnerabilities for therapeutic targeting approached to be investigated in future studies. A multi-Omics data integration approach was selected to achieve such ambitious aims. Herein, recent computational methodologies were applied to integrate and analyse transcriptomic with metabolomic profiles derived from cancer patients, as well as cell lines, mostly from mature B-cell neoplasms. Mature B-cell neoplasms, such as Chronic Lymphocytic Leukaemia (CLL) and Non-Hodgkin Lymphomas (NHL), rise from the clonal expansion of mature B-cells and they are responsible for most newly diagnosed cases of haematological cancers worldwide. The second chapter of this thesis presents an investigation into the transcriptome profile of CLL patients characterised by a distinct clinical response. Deregulated metabolic genes and pathways were identified between rare CLL cases that have undergone spontaneous regression versus CLL cases with poor clinical outcome. CLL cells from cases with poor outcome presented a differential reliance on oxidative phosphorylation and mitochondrial respiration compared to spontaneous regressed CLL cells. Going beyond traditional gene expression analysis, we performed an integration of transcriptomics profiles with Genome Scale Metabolic Models to identify metabolic genes as potential vulnerabilities in CLL. Our findings emphasise the important role of metabolic reprogramming in CLL and suggest the possibility of targeting metabolism for future studies and therapeutic approaches. The third chapter of this thesis describes a study exploring cancer metabolism in aggressive NHL associated with germinal centre development, focusing on endemic Burkitt Lymphoma (BL) and the germinal-centre–like subtype Diffuse Large B-cell Lymphomas (DLBCL). Analysis of the transcriptome of primary tumours revealed that BL cases possessed a distinct gene expression profile compared to DLBCL cases. This BL profile is suggestive of altered function of metabolism with elevated expression in serine metabolic genes, the c-Myc and mTORC1 pathways. On the opposite, DLBCL cases appeared to be dependent on extracellular signals from cytokines (INFγ response) or inflammation, possibly to trigger activation of intracellular signalling pathways that impact metabolism. Furthermore, integrative analysis at the pathway level between transcriptomic and metabolomic datasets from cell lines, indicated a dependency of BL cells on non-essential amino acid metabolism and particularly on the alanine, aspartate and glutamine metabolic pathways. These results not only highlighted key metabolic regulators in NHL, but most importantly, demonstrated the necessity of understanding and monitoring metabolic properties in these lymphomas. Finally, chapter four describes work undertaken to explore the transcriptomic and metabolic diversity of cancer cell lines. Machine learning approaches were applied to integrate and analyse Omics datasets retrieved from the Cancer Cell Line Encyclopaedia (CCLE) database. Unsupervised analysis highlighted the distinct transcriptomic and metabolomic profile of haematopoietic cell lines compared to other tumours. Taking a supervised approach enabled us to associate gene expression changes in cytoskeleton and cell adhesion molecules with aberrant metabolites levels, such as xanthine and creatinine. Together, these observations provide proof of concept for the highly dynamic variations between transcriptome and metabolome in different cancers. In summary, this work portrays the power of multi-Omics data integration to unveil key elements in metabolic reprogramming of haematological cancers and raises numerous questions and new hypotheses for future metabolic studies

Crosstalk between AML and stromal cells triggers acetate secretion through the metabolic rewiring of stromal cells

Acute myeloid leukaemia (AML) cells interact and modulate components of their surrounding microenvironment into their own benefit. Stromal cells have been shown to support AML survival and progression through various mechanisms. Nonetheless, whether AML cells could establish beneficial metabolic interactions with stromal cells is underexplored. By using a combination of human AML cell lines and AML patient samples together with mouse stromal cells and a MLL-AF9 mouse model, here we identify a novel metabolic crosstalk between AML and stromal cells where AML cells prompt stromal cells to secrete acetate for their own consumption to feed the tricarboxylic acid cycle (TCA) and lipid biosynthesis. By performing transcriptome analysis and tracer-based metabolic NMR analysis, we observe that stromal cells present a higher rate of glycolysis when co-cultured with AML cells. We also find that acetate in stromal cells is derived from pyruvate via chemical conversion under the influence of reactive oxygen species (ROS) following ROS transfer from AML to stromal cells via gap junctions. Overall, we present a unique metabolic communication between AML and stromal cells and propose two different molecular targets, ACSS2 and gap junctions, that could potentially be exploited for adjuvant therapy

Targeting asparagine and serine metabolism in germinal centre-derived B cells non-Hodgkin lymphomas (B-NHL)

BL and DLBCL are subtypes of B-cell lymphomas that arise from germinal centre B lymphocytes. Differentiation between BL and DLBCL is critical and can be challenging, as these two types of cancer share the same morphological, immunophenotypic, and genetic characteristics. In this study, we have examined metabolism in BL and DLBCL lymphomas and found distinctive differences in serine metabolism. We show that BL cells consume significantly more extracellular asparagine than DLBCL cells. Using a tracer-based approach, we find that asparagine regulates the serine uptake and serine synthesis in BL and DLBCL cells. Calculation of Differentially Expressed Genes (DEGs) from RNAseq datasets of BL and DLBCL patients show that BL cancers express the genes involved in serine synthesis at a higher level than DLBCL. Remarkably, combined use of an inhibitor of serine biosynthesis pathway and an anticancer drug asparaginase increases the sensitivity of BL cells to extracellular asparagine deprivation without inducing a change in the sensitivity of DLBCL cells to asparaginase. In summary, our study unravels metabolic differences between BL and DLBCL with diagnostic potential which may also open new avenues for treatment

Association of Vitamin D Receptor Gene Polymorphisms with Serum Vitamin D Levels in a Greek Rural Population (Velestino Study)

Background/Aim: An alarming increase in vitamin D deficiency even in sunny regions highlights the need for a better understanding of the genetic background of the vitamin D endocrine system and the molecular mechanisms of gene polymorphisms of the vitamin D receptor (VDR). In this study, the serum levels of 25(OH)D3 were correlated with common VDR polymorphisms (ApaI, BsmI, FokI, and TaqI) in 98 subjects of a Greek homogeneous rural population. Methods: 25(OH)D3 concentration was measured by ultra-HPLC, and the VDR gene polymorphisms were identified by quantitative real-time PCR followed by amplicon high-resolution melting analysis. Results: Subjects carrying either the B BsmI (OR: 0.52, 95% CI: 0.27–0.99) or t TaqI (OR: 2.06, 95%: 1.06–3.99) allele presented twice the risk for developing vitamin D deficiency compared to the reference allele. Moreover, subjects carrying 1, 2, or all 3 of these genotypes (BB/Bb, Tt/tt, and FF) demonstrated 2-fold (OR: 2.04, 95% CI: 0.42–9.92), 3.6-fold (OR: 3.62, 95% CI: 1.07–12.2), and 7-fold (OR: 6.92, 95% CI: 1.68–28.5) increased risk for low 25(OH)D3 levels, respectively. Conclusions: Our findings reveal a cumulative effect of specific VDR gene polymorphisms that may regulate vitamin D concentrations explaining, in part, the paradox of vitamin D deficiency in sunny regions, with important implications for precision medicine

Crosstalk between AML and stromal cells triggers acetate secretion through the metabolic rewiring of stromal cells

Acute myeloid leukaemia (AML) cells interact and modulate components of their surrounding microenvironment into their own benefit. Stromal cells have been shown to support AML survival and progression through various mechanisms. Nonetheless, whether AML cells could establish beneficial metabolic interactions with stromal cells is underexplored. By using a combination of human AML cell lines and AML patient samples together with mouse stromal cells and a MLL-AF9 mouse model, here we identify a novel metabolic crosstalk between AML and stromal cells where AML cells prompt stromal cells to secrete acetate for their own consumption to feed the tricarboxylic acid cycle (TCA) and lipid biosynthesis. By performing transcriptome analysis and tracer-based metabolic NMR analysis, we observe that stromal cells present a higher rate of glycolysis when co-cultured with AML cells. We also find that acetate in stromal cells is derived from pyruvate via chemical conversion under the influence of reactive oxygen species (ROS) following ROS transfer from AML to stromal cells via gap junctions. Overall, we present a unique metabolic communication between AML and stromal cells and propose two different molecular targets, ACSS2 and gap junctions, that could potentially be exploited for adjuvant therapy

Consulta favorable a la concesión de ayuda de costa a fray Francisco Plunqueto, agustino, para pasar a la Misión de Irlanda

Fecha del documento: 1675-05-28. 3 páginasConsulta del Consejo de Estado a la regente Mariana de Austria sobre el memorial remitido por fray Francisco Plunqueto, religioso de la Orden de San Agustín, en que refiere que ha concluido sus estudios en Teología en la Provincia de Castilla y desea pasar a Irlanda e Inglaterra a predicar el Santo Evangelio, para lo que suplica una ayuda de costa para poder hacer el viaje. El Consejo propone darle al suplicante los 100 ducados que se acostumbran, no habiéndoselos dado otra vez, y ser para el efecto que pide. Respuesta de la regente: "Así lo he mandado"Proyecto Proyección Política y Social de la Comunidad Irlandesa en la Monarquía hispánica y en la América Colonial de la Edad Moderna(siglos XVI-XVIII) (HAR2009-11339 - subprograma HIST) del Ministerio de Economía y Competitividad en colaboración con el Consejo Superior de Investigaciones Científicas (CSIC), Embajada de Irlanda en Madrid, National University of Ireland (NUI) Maynooth, University College Dublin y Trinity College DublinConsejo de EstadoMariana de AustriaOrden de San AgustínNo100 ducadosNoN