轉(zhuǎn)化醫(yī)學(xué)2 醫(yī)學(xué)分子生物學(xué)課件

1、轉(zhuǎn)化醫(yī)學(xué) （生物標(biāo)志物發(fā)現(xiàn)技術(shù)、疾病預(yù)測(cè)/預(yù)防、疾病診斷和治療）分子醫(yī)學(xué)概論：本節(jié)內(nèi)容轉(zhuǎn)化醫(yī)學(xué)的概念轉(zhuǎn)化醫(yī)學(xué)的興起轉(zhuǎn)化醫(yī)學(xué)提出的背景轉(zhuǎn)化醫(yī)學(xué)研究的內(nèi)容實(shí)現(xiàn)轉(zhuǎn)化醫(yī)學(xué)的途徑轉(zhuǎn)化醫(yī)學(xué)研究的結(jié)構(gòu)和范例轉(zhuǎn)化醫(yī)學(xué)研究的內(nèi)容一 分子標(biāo)志物的鑒定和應(yīng)用:基于各種組學(xué)方法篩選出早期診斷疾病、預(yù)測(cè)疾病(個(gè)體疾病敏感性預(yù)測(cè))、判斷藥物療效、評(píng)估患者預(yù)后的生物標(biāo)志物以及藥物靶標(biāo)。藥物靶標(biāo)藥物靶標(biāo)的確立有助于有針對(duì)性地探索新的藥物和治療方法，提高藥物篩選的成功率，縮短藥物研究從實(shí)驗(yàn)到臨床應(yīng)用階段的時(shí)間，提高研究效率。這些標(biāo)志物的開發(fā)應(yīng)用，將對(duì)疾病預(yù)防和診斷及治療發(fā)揮有效的指導(dǎo)作用。與此相關(guān)聯(lián)的產(chǎn)品開發(fā)將會(huì)是一個(gè)很大的產(chǎn)

2、業(yè)。轉(zhuǎn)化醫(yī)學(xué)研究的內(nèi)容二 基于患者的遺傳、分子生物學(xué)特征和疾病基本特征進(jìn)行分子分型，以此為基礎(chǔ)實(shí)施個(gè)體化的治療：惡性腫瘤、心腦血管病、糖尿病等大多數(shù)慢性病是多病因疾病，其發(fā)病機(jī)制復(fù)雜，疾病異質(zhì)性很大，不能采用單一方法(如同一藥物、相同劑量)進(jìn)行治療。對(duì)所有患者采用一種尺度(one size fits all)的醫(yī)療時(shí)代已經(jīng)過去?；诜肿臃中偷膫€(gè)體化治療將合理選擇治療方法和藥物(包括劑量)，達(dá)到有效、經(jīng)濟(jì)和最小的毒副作用的目的。分子醫(yī)學(xué)(molecular medicine)和個(gè)體化醫(yī)學(xué)(personalized medicine)都是轉(zhuǎn)化醫(yī)學(xué)研究產(chǎn)生的結(jié)果。 轉(zhuǎn)化醫(yī)學(xué)研究的內(nèi)容三 疾病治療反應(yīng)

3、和預(yù)后的評(píng)估與預(yù)測(cè)由于遺傳、營養(yǎng)、免疫等因素的差別，同一種疾病的患者對(duì)同一種治療方法或同一種藥物的效果和預(yù)后可表現(xiàn)出較大的差異。在分子生物學(xué)研究的基礎(chǔ)上，我們可利用經(jīng)評(píng)估有效的生物標(biāo)志物(如患者的基因分型、生化各種表型指標(biāo)等)，進(jìn)行患者藥物敏感性和預(yù)后的預(yù)測(cè)，選擇敏感的藥物和適當(dāng)?shù)膭┝?，以提高療效和改善預(yù)后。通過臨床與實(shí)驗(yàn)室關(guān)聯(lián)性研究(clinical-laboratory correlative studies)找出規(guī)律，闡明疾病的發(fā)生發(fā)展機(jī)制，以循證醫(yī)學(xué)的原則實(shí)施醫(yī)療工作。臨床前的多種模態(tài)Massoud & Gambhir，Genes & Development，2003 年Genomic

4、 /Genetic Considerations for CNS drugsGenes & the pharmaceutical enterpriseMethods for studying genesGenome-wide association studiesOpportunitiesBut now, ten years on, genetics has finally become a practical translational tool for industry Understanding of statistical issues High-fidelity high-throu

5、ghput genotyping Large repositories of population-based samples Consortia with standardized procedures Growing appreciation of the heuristic value of outliers Ever-growing number of robust validationsTarget ValidationTarget/CompoundInteractionPharmacodynamic ActivityDisease Biomarker& Disease Modifi

6、cationPatient Stratification Rare diseases have simple genetics.Common diseases have complex genetics.But now, genome-wide association studies allow efficient study of common diseases as well. Genetics The study of variation and its inheritanceIntrinsically probabilisticHeritability, segregation ana

7、lysis, linkage, associationGenomics The study of expression of all genes of an organismDeterministicTranscriptional profiling , in situ hybdrization, difference librariesMolecular BiologyThe study of molecules underlying genetics & genomicsDeterministicCloning; sequence and structural analyses; cros

8、s hybridization; site-directed mutagenesis; siRNA knockdowns; transgenic & knockout animal modelsThree distinct methodologies for three different questions Heritability estimates are always relative to the genetic and environmental factors in the population Heritability describes the population, not

9、 individuals within that populationHeritability can be estimated in controlled experiments & in population studiesPhenotype (P) = Genotype (G) + Environment (E). Var(P) = Var(G) + Var(E) + 2 Cov(G,E). If Cov(G,E) = 0. then H2 = Var(G)/ Var(P)Genetic analyses should only be undertaken if there is sig

10、nificant heritabilityUnusual high density families - dominant - point mutations (or microdeletions / duplications) in genes of major effect LinkageCommon, adult disorders without pronounced familial grouping- multiple genes of additive effect- often major environmental interactionsAssociationThe pat

11、tern of inheritance dictates the optimal genetic approachRare sporadic childhood disorders- Chromosomal rearrangements (or recessives)- Responsible genes in breakpoints or duplications/deletions SequencingFigure 1. Pedigree structure of the two Chinese families with tooth agenesis. High-density fami

12、lies ideal for linkage analysisGenomic /Genetic Considerations for CNS drugsGenes & the pharmaceutical enterpriseMethods for studying genesGenome-wide association studiesOpportunitiesLinkage & Association same general principle, different time scalesCrossovers increase with distanceLinkageAssociatio

13、n20 generations1 Score genomic DNA from a very large sample of cases & controls for a very large number of single-nucleotide polymorphisms (SNPs) Compare the frequencies among cases & controls Sites that differ significantly between cases and controls are then validated in independent samplesGenomew

14、ide association studies are based on a very simple ideaLessons learned from Genome-Wide Association Studies (GWAS,基因組相關(guān)性研究)Genome-Wide Association Studies (GWAS) work Effect sizes are usually small, so big samples needed Rigorous quality control is paramount GWAS may fail to detect certain susceptib

15、ility genesImportant to look well beyond the top few hits Collaboration is important Phenotype/selection is important Validation is criticalEvery SNP counts “Low-hanging fruit” lead to more variants Effect sizes are usually small, so big samples are needed Theory predicts that alleles of small effec

16、t are more frequent than alleles of large effect Wellcome Trust Case Control Consortium (WTCCC) GWASs of seven common diseases found per-allele odds ratios of 1.21.5 Reasonable power to detect such loci requires 2000 cases and 2000 controls Failures to replicate findings in modestly sized samples do

17、 not constitute refutation Confidence attributable to a significance level is influenced by sample size Rate of true positives increases with sample size because power to detect true effects increases Rigorous quality control is paramount Enormous data sets (samples & SNPs) in GWASs provide large op

18、portunities for spurious associations Data must be cleaned thoroughly to remove low-quality DNA samples, genotype calls & individual samples Within WTCCC the best predictor of an SNP with poor QC was a highly significant difference in genotype distributions between cases and controls - validation is

19、 criticalCollaboration is important Benefits from collaborations that increase total sample sizes , test consistency & generalizability of findings Aggressive, very early, proactive data sharing key to identification of several susceptibility loci not evident in any single study aloneStandard phenot

20、yping, threshholds for genome calls, raw data sharing Diabetes Mellitus (Types 1 & 2), coronary artery disease, ankylosing spondylitis benefited from collaborationsGenomic /Genetic Considerations for CNS drugsGenes & the pharmaceuticals enterpriseMethods for studying genesAssociation studiesOpportun

21、ities Lessons for Experimental Neurotherapeutics Learn from rare Mendelian variants of genes encoding potential drug targets (OMIM) Schizophrenia, autism, restless legs syndrome, early onset depression, bipolar disease, multiple sclerosis, Alzheimer disease, ADHD, & dyslexia are heritable common dis

22、eases tractable for GWAS Do not succumb to the temptation of relaxing diagnostic criteria to boost sample size Five Phases of ResearchPhase 1Phase 2Phase 3Phase 4Phase 5Basic ResearchMethods DevelopmentEfficacy TrialsEffectiveness TrialsDissemination ResearchFive Phase ModelBasic researchMethods dev

23、elopmentDevelopment of outcome measures, pilot studiesEfficacy trialsevaluations of health status or behavior change under scientific conditionsEffectiveness trialsevaluations under real or usual conditionsDissemination trialsExamine and evaluate conditions that promote or impede widespread useFive

24、Phase ModelPhase models assume linear progression from basic research to clinical applicationEach of five phases could work in a feedback loopEx. Phase 2 (Methods development: Development of outcome measures, pilot studies) could relate to dissemination (phase 5) which could feedback to other method

25、s of development (Phase 2)Eight Phase ModelBasic researchHypothesis developmentPilot-applied researchPrototype evaluation studiesEfficacy trialsTreatment effectiveness trialsImplementation effectiveness trialsDemonstration evaluationsPersonnel RolesResearcher-practitioner teamDoctorate level researc

26、hersPersons trained for applied workResearch planning, implementation analysis, data management, outcome analysis, reportsHealth promotion practitionersRecruitment, scheduling, maintaining field relationshipsCommunication necessary to facilitate translationTranslational ModelsFive-Phase ModelEight-P

27、hase ModelNIH Type 1 &Type 21.Basic research1. Basic research2. Hypothesis developmentType 12. Methods development3. Pilot-Applied research4. Prototype evaluation studies3. Efficacy trials5. Efficacy trials5. Effectiveness trials6. Treatment effectiveness trials7. Implementation effectiveness trials

28、Type 25. Dissemination8. Demonstration evaluationsCosts of a Translational FocusRisks undermining basic scienceDe-emphasizes technique developmentRests on accurate predictions of needRisks the creation of conflicts of interestFrequently tied to proprietary advancesHuman-subjects concernsRisks devalu

29、ing the academic enterpriseKnowledge for the sake ofConfounds academic and financial/health missionsCf. Sugarman & McKenna (2003)Early Clinical Study Designs, Emphasizing Proof-of-Concept Trials An industry perspectiveA Good Proof-of-Concept (POC) Model ?Quick to recruit relatively healthy subjectsA

30、llow a supervised setting with intense monitoring for efficacy and safetySpecific to a subtype of pain, generalizable to the entire population with that painSpecific to clinical symptoms rather than disease typeSensitive to show dose response in efficacySensitive enough to pick up side effectsObject

31、ive enough to rule out placebo response Simple enough to allow for multiple different sites without unduly increasing variabilityInclude comparator for assay sensitivityHow to Customize?“a careful sequential plan involving only a few key studies can provide sufficient basis for embarking on phase 3.

32、” (Sheiner, Clin Pharmacolog Ther 1997)“Why Math Will Rock Your World” (S. Baker, Business Week, Jan 3, 2006 coverstory) describing new ways math will be used in all sectors, including researchRudin M., Weissleder R.；藥物發(fā)現(xiàn)和研發(fā)的分子成像技術(shù) Nat. Rev. Drug Discov.，2，123-131，2003 年成像技術(shù)在藥物發(fā)現(xiàn)和研發(fā)中的應(yīng)用轉(zhuǎn)化醫(yī)學(xué)研究的結(jié)構(gòu)和范例美

33、國國立衛(wèi)生研究院（National institute of Health, NIH）蘇格蘭與 Wyeth的國際合作NIH27 InstitutesIntramural vs Extramural researchAnnual Budget: $30 billionNational Center for Medical Rehabilitation Research (NCMRR) - $77-90 millionNIH Roadmap. In Sep 2003, NIH Director Elias A. Zerhouni, M.D., laid out a series of far-re

34、aching initiatives known collectively as the NIH Roadmap for Medical Research. Designed to transform the nations medical research capabilities and speed the movement of research discoveries from the bench to the bedside. Developed with input from more than 300 nationally recognized leaders in academ

35、ia, industry, government, and the public, it provides a framework of the priorities the NIH must address to optimize its entire research portfolio (投資組合). It lays out a vision for a more efficient and productive system of medical research and identifies the most compelling opportunities in three mai

36、n areas: new pathways to discovery, research teams of the future, and re-engineering the clinical research enterprise. NIH RoadmapApproach to accelerate fundamental discovery and translation of research knowledge into effective prevention strategies and new treatments Strategic initiatives will addr

37、ess critical roadblocks and knowledge gaps that currently constrain rapid progress in biomedical research.Synergize the work of many NIH Institutes and CentersNIH RoadmapAppx. 36% of budget clinical research80% budget for extramural research, 10% budget for Intramural including 1200+ investigators C

38、linical Center model facility for translational research and trainingResult of changing health care needs and costs require changes in biomedical researchShift from acute to chronic Aging of populationPublic health challengesNIH RoadmapPerceived loss of talent in translational medicine and clinical

39、sciencesDifficulty finding scientist collaborators who can translate and clinically apply from basic scienceResearchers interested have difficulty finding facilities to apply their interestsNIH RoadmapDevelop national system of interconnected clinical research networksNIH National Electronic Clinica

40、l Trials and Research Network (NECTAR)Possible National Clinical Research Associates ProgramPatient Reported Outcomes Measurement Information System (PROMIS)Facilitate comparison among research studiesEnhance measurement precisionDevelopment of the CRCThe clinical research center (CRC) reflects the

41、parallel priorities of patient care and clinical researchProximity of research labs and patient-care units facilitates interactions between scientists, clinicians, and patient volunteersPermits clinician-scientists to work both in the lab and with patientsHelps clinicians and basic scientists learn

42、from each other in gathering places, and encourages the development of young scientists interested in clinical research. NIH Clinical Research Center242 inpatient beds, 90 day hospital bedsEvidence to Practice GapMedical journals must facilitate access and understanding of new knowledge for it to be

43、 implementedHealth researchers must communicate to researchers and practitionersHealth profession teachers should emphasize transitional processesClinical ResearchIncludes:Clinical trialsOutcomesHealth deliveryEpidemiological and psychosocial researchTranslational clinical research requires:Physicia

44、n-investigator skilled in biomedical scienceRecognition of appropriate patients to investigateClinical Research2 types of translational clinical investigatorsDisease-oriented researcher primarily working in labs or with animals, not patientsPatient-oriented translational clinical investigators (POTC

45、I)Clinical ResearchNIH and Academic Health Centers (AHC) need to support Patient-oriented translational clinical investigators (POTCIs)National bird of academic medicine may be the craneAHCs must foster collaboration in clinical researchFocus on publications needs to be expanded to include all autho

46、rs contributionsClinical Research“Cs” of clinical research:Clinical focus - interest in a disease and pts with itCollaboration with basic scientists and full time physiciansCourage to learn new techniques and approachesCooperative spousesConflict of interestCaring mentorsClinical Research ContinuumS

47、ung, NS, et al, JAMA March 12, 2003 Vol 289, No. 10Wyeth ResearchManaging Innovative Industry-Research Partnerships惠氏制藥公司(Wyeth)2006年5月：蘇格蘭衛(wèi)生部部長宣布蘇格蘭將與 Wyeth進(jìn)行一次特殊的國際合作，共同在蘇格蘭啟動(dòng)世界上第一個(gè)轉(zhuǎn)化醫(yī)學(xué)合作研究中心。轉(zhuǎn)化醫(yī)學(xué)（TranslationalMedicine）研究致力于彌補(bǔ)基礎(chǔ)實(shí)驗(yàn)研發(fā)與臨床應(yīng)用間的鴻溝，它通過研究可診斷及監(jiān)測(cè)人類疾病的新參數(shù)，為開發(fā)新藥品及研究新的治療方法開辟出一條具有革命性意義的新途徑。據(jù)悉，該

48、項(xiàng)目的總投資額接近5000萬英鎊。此次合作將充分聚合蘇格蘭和惠氏公司的專業(yè)精英力量?；菔现扑幑?Wyeth)轉(zhuǎn)化醫(yī)學(xué)研究針對(duì)的新參數(shù)被稱為生物標(biāo)志物（biomarkers），它們是新近發(fā)現(xiàn)的蛋白質(zhì)或指示劑，可通過患者的血液樣本或X光片檢測(cè)出來，進(jìn)而能用于觀察治療的進(jìn)展以及心臟病、癌癥、抑郁癥、骨質(zhì)疏松癥等患者對(duì)治療的反應(yīng)。生物標(biāo)志物還有助于探索新的治療方法。這次合作中，該項(xiàng)研究也被包括在蘇格蘭的?？婆R床試驗(yàn)方面。這些試驗(yàn)將縮短新的治療方法從實(shí)驗(yàn)階段到臨床階段的時(shí)間，還可提高醫(yī)護(hù)和治療工作的質(zhì)量。此外，它還能有助于根據(jù)不同的個(gè)體需要來調(diào)整處方，便于醫(yī)生發(fā)現(xiàn)哪些藥物對(duì)哪類病人更為有效，從而增強(qiáng)治

49、療的針對(duì)性，確?；颊叩玫角‘?dāng)?shù)闹委?。Wyeth maintains a strong commitment to R&DR&D Spend$ Millions040080012001600200019922005240028000246810121416198995012006# CompoundsCompounds intoDevelopmentWyeth is pursuing novel targets in many difficult to treat diseasesCV/MDThrombosis ThrombosisMetabolic SyndromeAtherosclerosi

50、sNSAlzheimers DiseaseSchizophreniaStrokeMuscular DystrophyOsteoarthritisUterine FibroidsWH/MSD A significant portion of these targets are unprecedented The clinical development path is long, difficult or uncertainINFMultiple SclerosisLupus PsoriasisONCKinase InhibitorsAntibody-toxins Source: 2005 Gl

51、obal R&D Performance Metrics Programme: Industry Success Rates Report, CMR International, May 2005, p. 7Phase 1Registration1994 - 961995 - 971996 - 981997 - 991998 - 001999 - 011994 - 96Phase 31995 - 971996 - 981997 - 991998 - 001999 - 011994 - 961995 - 971996 - 981997 - 991998 - 001999 - 01Phase 20

52、%10%20%30%40%50%60%70%80%90%100%1994 - 961995 - 971996 - 981997 - 991998 - 001999 - 01Year of Entry into PhaseSuccess RateInnovation has resulted in higher clinical attrition across the industryII期，也被稱為治療探索期,去證實(shí)用來治療特定疾病的藥物的有效性,也可以與作用肯定的標(biāo)準(zhǔn)藥物組或安慰劑組進(jìn)行比較，觀察疾病的反應(yīng)情況.Lack of efficacy and safety issues are

53、the major causes of Phase 2 attritionAdapted from: DiMasi, Clin Pharmacol Ther, 2001;69(5):297-307EconomicsEfficacySafetyOther33.837.619.69% failuresNow 55%Both the proportion & absolute number of compounds that prove safe & effective in humans is declining, despite an increasing number that are saf

54、e and effective in animal modelsTarget/DiseasePlatforms: “omics” Chemical biologyImmunoassaysImagingInformation Technologiesfor integrationAnimal Biomarker FingerprintHuman Biomarker FingerprintSo how can the most promising drug candidates be identified earlier in development? Translational Medicine

55、 Animal models do not accurately predict the effects of drugs in man Discover and develop biomarkers to measure the effects of a drug in humans Better predict drug safety and efficacy in manTranslational Medicine bridges the gap between pre-clinical and clinical studies A tool to bridge the gap betw

56、een preclinical and clinical studies Allows us to understand the likely behavior of experimental medicines in humans Enables cost-effective determination of efficacy through use of biomarkersEnables cost-effective determination of safety through the use of biomarkersClinical DevelopmentDiscovery Res

57、earchTranslational medicineTraditionally, academia and pharma differ on their views of Translational MedicineAcademic viewDiscovering new drug targetsDeveloping HTP capacityDeveloping drugs for orphan diseasesAny clinical academic research“Becoming more industrial”Pharma viewResearch instituteTechno

58、logy centers (genetics, genomics, imaging) Clinical chemistry and biomarker labsCross functional teams“Becoming more academic” At Wyeth, TMed is integrated into Drug Discovery and Clinical DevelopmentTMedClinicalDiscoveryR&DBiomarkerLabBiomarker OperationsTATABiotechClinicalOperationsOutsourcing & d

59、ata managementAssay validation & sample analysisBiomarker implementation strategy & researchSample procurement & exploratory studiesCandidate biomarker identification Biomarker discovery strategy & researchThe focus of TMed has moved from technology to strategic therapeutic areasTechnology focusOmic

60、sImagingImmunoassayCV/MDINFONCTherapeutic focusA “Biomarker Roadmap” guides the research needed for a drug target and disease indicationBiomarkers are the key to success, and serve a number of purposesA biomarker is a quantifiable biological measure that correlates with a physiological, pathological