Metabolòmica Marta Cascante Integrative Systems Biology, Metabolomics and Cancer lab Department of Biochemistry and Molecular Biology Institute of Biomedicine University of Barcelona (IBUB) E-mail: [email protected] http://www.bq.ub.es/bioqint/arecerca.html DNA Genomics RNA Transcriptomics Protein Proteomics Proteins Biochemicals (Metabolites) Metabolomics FROM MOLECULAR BIOLOGY TO SYSTEMS BIOLOGY Cytomics Genomics Information Proteomics Metabolomics Fluxomics SYSTEMS BIOLOGY Highest capacity to predict phenotype Metabolomics and fluxomics in the systems Biology approach Driving force: Development of high-throughput data-collection techniques, e.g. microarrays, protein chips, NMR, LC/MS-GC/MS…. allow to simultaneously interrogate all cell components at any given time. From molecules to networks: transcription/regulatory network ... - protein-protein interaction network - signaling network - metabolic network -These networks are not independent but form “network of networks“ -Metabolic network crosstalk with other networks must be considered in a systems biology approach Metabolomics and fluxomics in the systems Biology approach Central dogma of molecular biology: Gene mRNA Proteines Metabolites -Biological processes regulation is a complex phenomena more “democratic” than “hierarchical” Metabolites are not only the “end point” also the “driving force”? • The study of the total metabolite pools (metabolome) in a cell-organism at one particular point in time. • Metabolomics allows direct measurement of multiple low-molecular-weight metabolites from a biological sample. • Metabonomics (often named metabolomics) The study of the systemic biochemical profiles and regulation of function in whole organisms by analyzing a metabolome in biofluids and tissues Complementary approaches: • Highthroughput metabolite profiling: the identification of the specific metabolic profile that characterizes a given sample, i.e. the set of all of the metabolites or derivative products (identified or unknown) detected by analysing a sample using a particular technique. Biomarkers identification etc..... • Target metabolomics: Selected known metabolites are analysed: Biological question, biomedical hypothesis... drives the analysis of a set of compounds that are related to specific pathways. Challenges : all metabolic activity has to be stopped in the moment of sampling • Rapid sampling and fast quenching needed (much faster than the turnover times of the metabolite pools) • Complete extraction • No metabolite degradation during extraction/processing/storage • No enzymatic conversion during sample processing Obtaining proper “snapshots” of the metabolome in time requires Standard Operation Protocols. Validation for each experiment necessary. Metabolome analysis: The metabolome does not consist of a limited number of building blocks…. we are far away to have a “microarray”! -Large differences in: Physicochemical properties (polarity, hydrophobicity), structure, concentration range…… Combination of techniques is necessary Metabolomics experimental approaches: • Enzymatic assays, HPLC, Capillary electrophoresis-mass spectrometry (CE-MS/MS) • Liquid chromatography-mass spectrometry (LC-MS/MS) Currently most • Gas chromatography-mass spectrometry (GC-MS) used methods • NMR Analytical Technologies NMR spectroscopy Solution state (plasma, urine, extracts) MAS (tissue extracts) in vivo spectroscopy Relatively robust GC- and LC-Mass spectroscopy More analytically sensitive Potentially truly global Problems with ionisation What is needed? Van der Greef et al. “The Role of Metabolomics in Systems Biology” In: Metabolic Profiling, Kluwer (2003). - Catalogue of all metabolites that can potentially be found in human tissues. -Purified metabolites to be used as standards and/or spectral libraries. -SOPs for different platforms and appropriate chemometrics tools Metabolomics: diagnostic, mechanism, biomarkers.... Tissue or biofluid sample Bioanalytical tools 1. Mass spectrometry 2. 1H NMR spectroscopy Measure the metabolite profile e.g. by NMR Statistical bioinformatic tools Treat profile as ‘fingerprint’ for diagnostic purposes Explore profile to determine mechanism and potential biomarkers E.g. plasma samples randomly selected from 12 students…. 2 abnormal profiles - too much alcohol? - diseased? 10 of the profiles are very similar (“normal”) Use computerized pattern recognition methods alcoholic diseased normal E.g. plasma samples randomly selected from 12 students…. histidine citrate Insight into mechanism of disease/toxicant Example: applications in cancer The Metabolome of an organism is the result of the in vivo function of gene products and is, is closely tied to its physiology and its environment (what is eat or breath). Analysis of human samples Blood – serum or plasma Urine Tumour samples Biopsies Cell based model studies Choice of cell line Cell content or secreted metabolites Biomarker Discovery Systems Biology Approach: - Drug target discovery Fluxomics • The distinct metabolic processes involved in metabolites production and degradation are dynamic and finely regulated and interconnected. • Knowledge of the metaboloma is not enough to predict the phenotype as give only an instant 'snapshot' of the physiology of that cell. • For a characterization of metabolic networks and their functional operation quantitative knowledge of intracellular metabolic fluxes is required. Fluxomics is the field of “omics” research dealing with the dynamic changes of metabolites over time, i.e. the quantitative analysis of fluxes through metabolic pathways Methods Intracellular fluxes can be estimated through: • Knowledge of network stoichiometry •Quantitative measurements of metabolites at different times and/or incubation of cells/organisms with labeled substrates (i.e. 13C) •Interpretation of stable isotope patterns in metabolites using appropriate software packages. Metabolomics and fluxomics in Cancer Systems Biology • Transcriptomics and proteomic analysis do not tell the whole story of what might be happening in a cell. • Metabolomics anf fluxomics offers a unique opportunity to look at relationships between genotype and phenotype as well as with environment. -Metabolomics and fluxomics in cancer: -From tumor metabolome to new therapies targeting tumor metabolome? CANCER Changes in GENOME Oncogenes and tumor supressor genes… Changes in PROTEOME Signaling pathways, transcription factors… Activated growth signalling Evading cell death and senescence Tissue invasion and metastasis Limitless replicative potential Sustained angiogenesis Evading immune surveillance DNA damage and DNA replication stress Metabolic stress Mitotic stress Genomic instability (modified from Negrini et al., 2010) Accelerated, disordered and decontrolled proliferation of tissue cells that invades, moves and destroys as well as in a local level as in distance, other health tissues of the organism. CANCER Changes in GENOME Oncogenes and tumor supressor genes… Changes in PROTEOME Signaling pathways, transcription factors… Satisfy energetic tumor requirements Creation of acidic environment Alterations in METABOLISM TUMOR METABOLOME Insensibility to O2 Decrease of pyruvate oxidation in the mitochondria General increase of glycolytic intermediates Is metabolic network reorganization a consequence or a cause of tumor progression? Could metabolism be used as therapeutic target against tumor progression? TUMOR METABOLOME High glucose consumption and lactate production. Warburg effect Activation of biosynthetic pathways Expression of isoforms, changes in enzymatic activities and affinities NADPH NADPH HK II Glucose 6PGL G6P Ru5P 6PGT F6P - M2-Pyruvate kinase (M2-PK) Fatty acids F1,6BP TKTL1 S7P DHAP - Transketolase-like 1 (TKTL1) R5P 2PG PEP Palmitate GAP 1,3BPG 3PG - Hexokinase I and II (HK) E4P X5P Acetyl-CoA Nucleotide synthesis M2-PK Acetyl-CoA Malonyl-CoA Citrate Pyr Lactate Citrate Lactate Pyr CO2 See as a review: Robust metabolic adaptation underlying tumor progression Vizan P, Mazurek S and Cascante M, Metabolomics (2008) 4:1–12 CANCER AS A METABOLIC ALTERATION Cancer cells are perfect systems to invade and parasite other tissues Robust metabolic profile FRAGILITY Exploitable Target for CANCER THERAPY? unexpected perturbations MULTIPLE HIT CANCER THERAPY AT METABOLIC LEVEL Tumor metabolism robustness counteracts single hits Multiple hit strategies can avoid bypass of single inhibitions Tumor metabolism response to multiple inhibition is unpredictable Rational design of new therapeutical combinations is necessary A 1 In series Synergy reactions C E B 3 D 2 F Addition Antagonism Parallel reactions MULTIPLE HIT CANCER THERAPY AT METABOLIC LEVEL Tumor metabolism robustness counteracts single hits Multiple hit strategies can avoid bypass of single inhibitions Tumor metabolism response to multiple inhibition is unpredictable Rational design of new therapeutical combinations is necessary A B 1 3 Synergy C 2 KNOWLEDGE E F OF THE DMETABOLIC NETWORK Addition Antagonism FLUXOMICS FOR THE ANALYSIS OF TUMOR METABOLOME Metabolomics and Fluxomics are necessary for rational design of new therapeutical combinations TRACER-BASED METABOLOMICS Pyruvate [1,2- 13C]-glucose carboxylase Pyruvate dehydrogenase [2,3- 13C]-pyr Fatty acid synthesis Metabolome [1,2- 13C]-acetylCoA [2,3-13C]-OAA Metabolic Pathways [5,6- 13C]-citrate FLUXOME Glutamate [2,3-13C]-ketoglutarate [4,5- 13C]-ketoglutarate Glutamate AN ALGORITHM FOR DYNAMICS ANALYSIS OF THE ISOTOPE TRACER DISTRIBUTION IN METABOLITES EXPERIMENTAL TOOLS COMPUTATIONAL TOOLS Experimental Obtain dynamictools data for Tracer-based metabolomics permit to obtain dynamic data that need to be analyzed and can be TRACER-BASED used for fluxes METABOLOMICS estimation ALGORITHM Able to analyze: They should permit Evaluate metabolic to fluxes evaluate metabolic fluxes under non-steady state in situ METABOLIC conditions to FLUXand MAP provide insight to the kinetic mechanisms which govern the metabolic networks in vivo Data generated on different platforms ( GC-LC/MS, NMR) on the metabolites levels and isotopic isomer distributions obtained by incubation with stable labeled substrates the non-steady state of metabolism (time courses) By using enzyme kinetic idata in combination with in vitro or in vivo metabolomic data Useful to: Analyze and understand the metabolic adaptations supporting cell functions Selivanov et al, 2004 Bioinformatics Design metabolic interventions in drug development Selivanov et al, 2005 Bioinformatics Selivanov et al, 2006 Bioinformatics DEVELOPING DRUGS FOR NEW THERAPEUTICAL STRATEGIES AIMING TO DISRUPT METABOLIC ROBUSTNESS OF CANCER CELLS Exploiting tumoral metabolic adaptation of adenocarcinoma cancer cells for new antitumoral therapies Pentose-phosphate pathways enhanced Glucose G6P oxidative Purine ribose Pyrimidine F6P non oxidative oxidative ROBUSTNESS GAP Pyruvate non oxidative Phase Plane Analysis Lactate ? AcetylCoA FRAGILITY DEVELOPING DRUGS FOR NEW THERAPEUTICAL STRATEGIES AIMING TO DISRUPT METABOLIC ROBUSTNESS OF CANCER CELLS Multiple hit target strategy to disrupt this balance 1-Control 2-MTX 3-DHEA+MTX 4-OT+DHEA+MTX DHEA MTX G6P G6PDH R5P 0,35 PRPP Purine Biosynthesis TKT 0,3 RNA dUMP dTMP 10 ,N -methylene OT Pyrimidine Ntetrahydrofolate Biosynthesis Dihydrofolate NADPH + H+ Glicine Tetrahydrofolate NADP+ 120 MTX 1 Viabilidad Viabilidad Viability 0,2 0,15 0,05 0 100 MTX nM MTX + 20 mM DHEA MTX + 2 mM OT + 20 mM DHEA 80 2 60 2 0,1 DHFR Serine oxidative 6 DNA Timidilate sintase 1 4 0,25 dTTP UMP 3 0 0,05 0,1 0,15 non oxidative 3 40 20 4 0 0 10 20 30 40 MTX (nM) (nM )) MTX (nM MTX 50 60 70 4 3 2 Oxidative/non-oxidative balance is essential to cancer cells and is a possible new target within the cancer metabolic network for novel therapies. Ramos-Montoya et al., 2006. Int J Cancer; 119(12):2733-41 MODULATION OF PPP DURING CELL CYCLE PROGRESSION IN HUMAN COLON ADENOCARCINOMA CELL LINE HT29 Cells do not have nucleotide reservoirs, so PPP must be regulated during cell cycle G6PDH activity SD G1 rich population G1 rich population S-G2 rich populationS-G2 457,41 14,22 rich population 554,96 14,81 TKT activity SD G1 rich population 29,79 1,10 S-G2 rich population 35,03 1,24 0,01 0 0-5h 5-10h 10-15h 15-20h Cell Cycle (IC50 inhibitors) %G1 %S %G2 60 40 20 0 Ct % Increase in ribose enrichment (Smn)/hour 0,03 0,02 80 OT+DH 0h Ct OT+DH 10h %G1 %S %G2 0h 81,7 12,7 5,6 5h 82,8 9,8 7,4 10h 58,1 35,4 6,5 15h 35,2 59,3 5,5 20h 21,8 60,2 18,1 Ct OT+DH 15h Ct OT+DH 20h G6PDH and TKT activities depend on cell cycle progression and are higher in S-G2 phases. This increase correlates with an augment in ribose phosphate synthesis in late G1-S phase. Avoiding pentose phosphate production G6PDH and TKT inhibitors are able to slow down cell cycle. Vizan et al., 2009. Int J Cancer; 124(12):2789-96 Characterization of metabolic adaptation underlying growth factor . angiogenic activation: Identification of potential therapeutic targets Exploiting angiogenesis metabolic adaptation of HUVEC cells for new antiangiogenic therapies 1.The activation of HUVEC cells produced by VEGF or FGF produced a similar pattern of glucose usage. 2. The inhibition of the VEGF receptor caused a decrease in the proliferation rate accompanied by a decrease in the pentose phosphate pathway activity and glycogen metabolism. 3. The Direct inhibition of key enzymes of glycogen metabolism and pentose phosphate pathways reduced HUVEC cell viability and migration. The inhibition of pentose-phosphate pathway and glycogen metabolism offers a novel and powerful therapeutic approach, which simultaneously inhibits tumor cell proliferation and tumor-induced angiogenesis. Vizan et al., 2009. Carcinogenesis; 30(6):946-52 TKTL1 AS BIOMARKER FOR TUMOR PROGRESSION IN COLORECTAL CANCER TNM classification of colon cancer according to American Joint Committee on Cancer (AJCC) Primary Tumor (T) Tis: Carcinoma in situ. T1-4: depending on local growth degree. Regional Lymph Nodes (N) N0: No regional lymph node metastasis. N1-2: depending on the number of regional lymph nodes affected. Distant Metastasis (M) M0: No distant metastasis. M1: Distant metastasis. Stage grouping according to AJCC STAGE 0 I IIA IIB IIIA IIIB IIIC IV T Tis T1-2 T3 T4 T1-2 T3-4 T1-4 T1-4 N N0 N0 N0 N0 N1 N1 N2 N0-2 M M0 M0 M0 M0 M0 M0 M0 M1 • TKT, and its isoenzyme TKTL1, play a key role for tumor cell metabolism. • 46 men + 17 women (69 12 years) with colorectal cancer in different stages were included to confirm TKTL1 as a biomarker for tumor progression. Stage I II III IV No. Samples 9 21 16 17 • TKTL1 Immunohistochemical staining of 2 mm thick sections of tumors was performed. (collaboration with Dr. Antoni Castells, Hospital Clinic) Diaz-Moralli et al. Plos One 2011; 11;6(9) e25323. RESULTS Mean 13,3 20,8 32,9 13,7 SD 7,9 9,9 11,5 8,7 Stage III tumors present the highest levels of TKTL1 expression (p=0,000008). TKTL1 expression Stage I II III IV (Relative value x 1000) 50 *** 40 30 20 10 0 Stage I Stage II Stage III Stage IV 40 (Relative value x 1000) TKTL1 expression P = 0.000008 35 30 25 20 *** 15 TKTL1 levels decrease significantly (p=0,0004) when distant metastasis appears (M). P = 0.0004 10 5 0 M1 40 P = 0.0014 35 30 25 20 15 10 5 0 N0 N 1-2 TKTL1 increase correlates significantly (p=0,0014) with regional lymph node affection degree (N). 40 (Relative value x 1000) ** 45 TKTL1 expression (Relative value x 1000) TKTL1 expression M0 50 * 35 P = 0.029 30 25 20 15 10 5 0 T 1-2 There is a slightly between TKTL1 levels growth (p=0,029). T 3-4 correlation and local METABOLIC CHANGES ACCOMPANYING TUMOR CELL DIFFERENTATION Histone deacetylase enzymes downregulate genes that cause or induce cell differentiation. Deacetylated chromatin HDI no gene expression N HAT HDAC HDI NHOH Acetylated chromatin O TSA O O Gene expresion ONa Butyrate (NaB) Differentiation HT29 TSA Butyrate (NaB) HT29 METABOLIC CHANGES ACCOMPANYING TUMOR CELL DIFFERENTATION GLUCOSE GLUCOSE NADPH NADPH RIBOSE G6P LACTATE RIBOSE G6P F6P F6P GAP GAP LACTATE PYR G6PDH PYR PDH OAA OAA Ac-CoA Ac-CoA o TSA Butirato or TSA Butyrate -cetoglutarate -cetoglutarate HDAC GLUTAMATE GLUTAMATE Differentiation HT29 Transformation HT29 Butyrate and TSA show similar effects on HT29 cells. Other fatty acids that are not able to induce differentiation not induce this changes -> The metabolics effects induce are due to histone deacetylase inhibition. Alcarraz-Vizan et al 2010 Metabolomics EARLY METABOLIC CHANGES PRECEED EDELFOSINE (ET-18-OCH3 ) INDUCED APOPTOSIS GLUCOSE GLUCOSE NADPH NADPH G6PDH G6PDH LACTATE F6P F6P GAP GAP LACTATE PYR PYR PDH PDH OAA RIBOSE G6P RIBOSE G6P OAA Ac-CoA Ac-CoA -cetoglutarate -cetoglutarate Jurkat cells without edelfosine Jurkat cells + low dosis edelfosine (apoptosis < 5%) •Low edelfosine (before apoptosis) : Krebs cycle and RNA synthesis increase , PPP decrease •Higher dosis (apoptosis): enhanced metabolic effects and ROS production Selivanov et al. BMC Systems Biology 2010, 4:135 EXTENDING METABOLIC MODELS TO ROS PRODUCTION: Important component of redox status is the level of reactive oxygen species (ROS) produced in mitochondria. Algorithms developed for isotopomer analysis and study of cancer metabolism network adaptation can be used to cope with the complexity of modelling ROS production and energetic metabolism in muscle. Selivanov et al. 2009 PLOS Computational Biology, In Press CONCLUSIONS FROM ROS MODELLING •The detailed modeling of electron transport in mitochondria identified two steady state modes of operation (bistability) of respiratory complex III at the same microenvironmental conditions. •Normally complex III is in a low ROS producing mode, temporal anoxia could switch it to a high ROS producing state, which persists after the return to normal oxygen supply. . •This prediction, which we qualitatively mechanism of anoxia-induced cell damage. validated experimentally, explains the Recognition of complex III bistability may enable novel therapeutic strategies for oxidative stress 0: Q-Q-bh-bl-c1-FeS-Q-Q 1: Q-Q-bh-bl-c1-FeS-Q-Q 2: Q-Q-bh-bl-c1-FeS-Q-Q Fe3++ QH2 ⇆Fe2++ Q-+ 2H+p Fe2++ c1ox ⇆Fe3++ c1red Q-+ blox⇆blred+ Q xxxxx011 ⇆xxxxx101+ 2H+p xxxx01xx ⇆xxxx10xx xxx0xx01 ⇆xxx1xx00 vf31 = kf31 ·Cxx01 vr31 =kr31 ·Cxx10 vf32 = kf32 ·Cx0xx01 vr32 =kr32 ·Cx1xx00 vf30= kf30 ·Cxxxxx011 vr30 =k r30 ·Cxxxxx101·Hp2 The scheme of reactions performed by complex III as it is generally accepted. One of two electrons taken from ubiquinol (QH2), which releases its two protons into the intermembrane space, recycles through cytochromes bh and bl reducing another quinone. The other electron continues its way to oxygen through cytochromes c1 and c and complex IV. Complexes I and II provide QH2. Selivanov et al., 2009. PLOS Comput. Biol. and Selivanov et al 2011, PLOS Comput. Biol. Developing a modelling environment, which links clinical characteristics with the redox status of cell Glycolysis NAD Glc Clinical Data connection ADP O2uptake Mitochondria Exhalates ATP NADH Pyr NAD TCA cycle Cit AcCoA NAD OAA NADH Succ ADP O2 Lac ATP RESPIRATION Clinical Data connection Lac Omics in Blood ROS ”OMICS” in biopsies O2 transport antioxidant system cell damage signalling Integration of existing models • Skeletal muscle bioenergetics – sub-cell • Mitochondrial reactive oxygen species (ROS) generation – sub-cell • Central and peripheral O2 transport and utilization – organ system (heart, lung, hemoglobin, skeletal muscle) • Pulmonary gas exchange – organ (lungs) • Spatial heterogeneities of lung ventilation and perfusion – tissue SYNERGY: Modeling and simulation environment for systems medicine: chronic obstructive pulmonary disease -COPD- as a use case (FP7) ACKNOWLEDGEMENTS Group of Integrative Biochemistry Department of Biochemistry and Molecular Biology, University of Barcelona Dr. Pedro de Atauri Dr. Vitaly Selivanov Dr. Josep Centelles Dr. Silvia Marín Dr. Gema Alcarraz-Vizán Miriam Zanuy Santiago Díaz-Moralli Susana Sánchez Adrián Benito Roldán Cortés Igor Marín Collaborators Hospital Clínic-IDIBAPS, University of Barcelona: Pneumology service, Institut del Torax,, directed by Dr. Josep Roca and Gastroenterology Department Dr Antoni Castells Financial support: SAF2005-01627, SAF2008-00164 from the Ministerio de Ciencia y Tecnologia of the Spanish Government SYNERGY, METAFLUX, ETHERPATHS from the European Union (FP7) ICREA ACADEMIA Award Autonomous Government of Catalonia