1212569_21823227.jpg logo_mu_cerne.gif 1212570_28446780.jpg logo_mu_cerne.gif Luděk Bláha, PřF MU, RECETOX www.recetox.cz BIOMARKERS AND TOXICITY MECHANISMS 13 – BIOMARKERS Summary and final notes OPVK_MU_stred_2 1212569_21823227.jpg logo_mu_cerne.gif Topics covered in the final presentation •Biomarkers at different levels –Omics –... and beyond • •Biomarkers in human medicine and drug development –Strategy and steps in development –Application examples 1212569_21823227.jpg logo_mu_cerne.gif Biomarkers have MANY APPLICATIONS ... such as: •Biomarkers in research –Search of “potential” therapies/drugs •Changes in biochemical responses provide information on efficiency and mechanism of action –Identification of “early markers” of chronic diseases •Early diagnosis (e.g. identification of developing cancer, coronary disease...) • •Biomarkers in medicine –Identification of status of an individual •Healthy vs Disease –Assessment of therapy/treatment •Efficiency – Did treatment improved situation? (improvements in biomarker responses) •Adverse or side effects of therapy • •Biomarkers in toxicology –Identification of status •Intoxicated (exposed) vs Controls •Forensic toxicology (e.g. consumption of drugs of abuse, alcohol etc) –Early warnings of future health consequences •Biochemical changes are detectable before the actual health problems – 1212569_21823227.jpg logo_mu_cerne.gif Biomarkers at various levels “omics” 1212569_21823227.jpg logo_mu_cerne.gif Biomarkers at different biological levels – „omics“ approach http://www.genetris.com/images/uploads/images/Biomarker_discovery.gif 1212569_21823227.jpg logo_mu_cerne.gif Biomarkers at different biological levels •“Omics” techniques –Systems biology research –Screenings of responses (differences) at all levels of biological organization – •GENOMICS –Relatively stable •not responding to environmental changes (e.g. Toxicants) –Can be used as “biomarkers of susceptibility” (SNPs and personalized medicine) – •OTHER “OMICS” layers –Epigenomics + Transcriptomics, Proteo-, Metabolo-... –Highly variable - responsive to environmental stress (including toxicants, therapy etc.) • 1212569_21823227.jpg logo_mu_cerne.gif Biomarkers at different biological levels 1212569_21823227.jpg logo_mu_cerne.gif http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageSer vice/Articleimage/2008/MB/b802534g/b802534g-f1.gif Hypothesis driven research Data driven research (focus on pathways) (omics & profiling) 1212569_21823227.jpg logo_mu_cerne.gif http://www.scielo.org.mx/img/revistas/rica/v29n1/a8f1.jpg Biomarkers at even higher levels – example: toxic metals 1212569_21823227.jpg logo_mu_cerne.gif Developments and applications of clinical biomarkers 1212569_21823227.jpg logo_mu_cerne.gif http://www.bloodjournal.org/content/bloodjournal/121/4/585/F1.large.jpg?width=800&height=600 3 key steps towards the biomarker establishment An example of protein-based biomarkers 1212569_21823227.jpg logo_mu_cerne.gif •Biomarker development –High numbers of endpoints (e.g. proteins) –Low numbers of samples compared (e.g. 10 controls vs 10 “treatments”) – •Biomarker validation –Decreasing number of markers –Increasing numbers of specimens (biological samples) – •Biomarker qualification and approval –Individual markers –Analytical methods validated and well established 3 key steps towards the biomarker establishment 1212569_21823227.jpg logo_mu_cerne.gif More detailed view: 5 steps leading to biomarker use in (clinical) practice http://www.molecularmedicineireland.ie/uploads/BiomarkerImage_210910.jpg DISCOVERY à VALIDATION STEPS à APPROVAL 1212569_21823227.jpg logo_mu_cerne.gif http://cisncancer.org/research/images/biomarker_discovery-rew.jpg EXAMPLE process of biomarker establishment – lung cancer diagnosis Which of the many changes are “significant” ? à Use quantitative metrics (see Following slide) 1212569_21823227.jpg logo_mu_cerne.gif http://www.plosmedicine.org/article/info:doi/10.1371/journal.pmed.1000046.g002/largerimage What is (what is not) a candidate biomarker: example flowchart Use of quantitative metrics during development 1212569_21823227.jpg logo_mu_cerne.gif Biomarker validation EXAMPLE Kim-1 protein levels and kidney clinical signs (histopathology grades 0-3) 1212569_21823227.jpg logo_mu_cerne.gif OMICS biomarkers in discovery and validation (1/2) http://bgiamericas.com/wp-content/uploads/2011/12/Overview-of-Multi-omic1.png http://bgiamericas.com/wp-content/uploads/2011/12/Overview-of-Multi-omic1.png 1212569_21823227.jpg logo_mu_cerne.gif OMICS biomarkers in discovery and validation (2/2) http://bgiamericas.com/wp-content/uploads/2011/12/Overview-of-Multi-omic1.png 1212569_21823227.jpg logo_mu_cerne.gif Summary and overview Toxicity mechanisms (MoA) and biomarkers 1212569_21823227.jpg logo_mu_cerne.gif Class summary and take home message * Molecular effects of toxicants = MoAs (1) * Propagate to higher levels (2), * … where they induce measurable “responses” - biomarkers (3) https://encrypted-tbn3.gstatic.com/images?q=tbn:ANd9GcTJLahZlgjt9hGQWAfTZhHoUTAU1dGT2XlAGT1vzWh0Ze3 _nMUH MoAs * Molecular interactions * Key targets ...: - DNA, RNAs - proteins (and their functions) - membranes * Complex mechanisms - Oxidative stress - Signalling and hormones - Detoxification 1 2 3 1 Biological organization Biomarkers - types - examples - methods 1212569_21823227.jpg logo_mu_cerne.gif Summary on toxicity mechanisms (MoA) and biomarkers •For excellent performance and successful exam student should: • 1.have an overview of different types of MoAs (see also point 2 below) and be able to link MoAs to higher level effects (toxicity) –Example: What is the in vivo manifestation (effect) after inhibition of AcCholE enzymes (mechanism)? [AcCholE inhibition propagates as neurotoxicity (effect)] –Be ready to discuss also in a opposite way –Example: What MoA can be beyond immunotoxicity? [Immunotoxicity can e.g. be caused by disruption of signaling pathways – LPS as an example] 2.know some details for selected example MoAs for different toxicant targets = based on your own preference select one example from the following 7 categories, learn details, and be ready to discuss (i.e. learn details for 1 out of 7 example modes of toxic action) 1.nucleic acids 2.proteins 3.membranes (lipids) 4.cellular 5.Complex 1 – detoxification/metabolization 6.Complex 2 – intra- and inter-cellular signalling, hormones 7.Complex 3 – oxidative stress 3.have understanding of biomarker issues •What is a biomarker and what properties it should have (or not to have)? •Why we search for them = how can they be used? •What different types and groups of biomarkers can be recognized? •What are suitable matrices for sampling and further analyses? •What methods do we use for analyses of biomarkers? (LCMS, ELISA, PCR, Proteins-WBs, Enzyme actvities) •What approaches are applied in biomarker discovery („hypothesis“ vs omics)? 4.and know example biomarkers Related to the point 2 above = based on your own interest (in point 2) learn about the effect biomarkers relevant for your selected toxicity mechanism • The final exam: = 4 open questions + follow-up „colloquium-like“ discussion Q1 + Q3 – general overview Q2 + Q4 – select one topic from those listed (1-7) and know details about mechanisms & biomarkers