临床药理学药物基因组与个体化医学2017

,Pharmacogenomics and Personalized Medicine,张 伟教授, 博士生导师中南大学湘雅医院临床药理研究所中南大学湘雅医学检验所,Outline,Pharmacogenomics and Pharmacogenetics;Single nucleotide polymorphism (SNP);Personalized medicine and Personalized therapy.,Part I：Pharmacogenomics and Pharmacogenetics,Pharmaceutical companies adopt “one-drug-fits-all” policy.Drugs do not work in many people.More than 90% drugs work only in 3050% of people.Adverse drug reactions (ADRs) are a common cause of morbidity and mortality.,Factors Contributing to Interindividual Variability in Drug Disposition and Action,Interindividual difference,AgeGenderRace/ethnicityNutrition statusCo-medicationsCo-mobiditiesLifestyle variablesSocial factorsGENETICS,Percentages of non-responders,Potential of Pharmacogenomics,HGP (Human Genome Project),Oct 1990 to 2003.Identify approximately 30000 human genome DNADetermine composition of the human genome DNA is about 3 billion nucleotides,The Era of Genomic Medicine,Earlier detection of genetic predisposition to disease;Improve the diagnosis of disease; Improve prediction of drug efficacy or toxicity.,Pharmacogenomics and Pharmacogenetics,遗传药理学（Pharmacogenetics, PGt) : 研究DNA变异如何引起药物反应差异属于药物基因组学的范畴药物基因组学 ( Pharmacogenomics, PGx) :研究DNA如何影响药物反应= 药理学 + 基因组学, 目标:药物反应的遗传易感性个体化药物治疗新医疗模式的变革,Part II：Single nucleotide polymorphism (SNP),CYP2C9*2,No enzymatic activity,430CT (Arg144Cys),Cys,The biological basis of individualized treatment is single nucleotide polymorphisms（SNPs）- Accounting for 90% human genetic variation,导致人类遗传易感性的重要因素导致人类药物代谢和反应差异的重要因素,GT突变,野生型 突变型,Difference in DNA sequence(SNP) Difference in encoding amino acid and protein structure and function,Ala,Ala,Ala,Arg,Arg,Lys,Asp,Asp,Asp,Asn,Asn,Asn,Cys,Cys,Cys,As gene,Bs gene编码改变但不改变氨基酸序列,Cs gene编码改变使氨基酸序列改变,G C A A G A G A T A A T T G T,G C G A G A G A T A A T T G T,G C A A A A G A T A A T T G T,1 2 3 4 5,1 2 3 4 5,1 2 3 4 5,.C C A T T G A C.,.C C A T T G A C.,G G T A A C T G.,G G T A A C T G.,.C C A T T G A C.,.C C G T T G A C.,G G T A A C T G.,G G C A A C T G.,.C C G T T G A C.,.C C G T T G A C.,G G C A A C T G.,G G C A A C T G.,wt/wtHomozygous wild-type,SNP forms three genotypes,X,X,X,wt/mHeterozygote wild type,m/mHomozygous mutations,等位基因（allele）-人的基因位于成对的染色体上（性染色体除外），因此每一种基因都有一对。,基因多态性（genetic polymorphism）-在正常人群中，由于同一基因位点上多个不同等位基因作用而出现两种或两种以上遗传决定的基因型，如果每种基因型的发生频率超过 1% 。,单核苷酸多态性（single nucleotide polymorphism，SNP）-在基因组水平上由单个核苷酸的变异所引起的DNA序列多态性。它是人类可遗传变异中最常见的一种，占所有已知多态性90% 以上。,表型（phenotype）-个体在一定环境条件下表现的性状。,基因型（genotype）-形成表型这种性状有关的遗传结构。,Individual differences in drug toxicity,Same dose, but different drug concentration in vivo and total amount,ineffectiveness safe and effective toxicity,Serious ADR全球死亡主要原因第 5 位美国每年因严重ADR死亡10万人我国因ADR住院：250万/年; 因ADR死亡：20万/年,Drug effect is determined by the polymorphism of drug metabolic enzymes，transporters and drug targets,pharmacokinetics,pharmacodynamics,Drug efficacy and toxicity of individual differences,Genomous,genovariation (single nucleotide polymorphism),drug targets,drug transporter,drug metabolic enzyme,DME in human liver,SNPs and phenotype distribution of DME,Phenotype distribution of CYP2D6 and drugs metabolized by CYP2D6,MetoprololProponololCarvedilolFlecainideDiacetolol DebrisoquineMexiletinePropafenone,Poor metabolizer,Extensive metabolizer,Ultra-rapid metabolizer,服用40 mg 奥美拉唑后,奥美拉唑 (mg/L),CYP2C19*2/*2,CYP2C19*1/*2,CYP2C19*1/*1,CYP2C19 基因型/表型基因剂量效应,AUC:,1.1 0.6,0.6 0.3,mg.h/L,5.32.2,1. 药物代谢酶基因变异与药物反应实例,0,10,20,30,40,50,60,70,80,90,100,UM,EM,EM/het.,IM,PM,Metoprolol plasma con.(ng/ml),1.3,3.9,14.2,50.8,80.5,Dose mg,100,100,100,78,74,浓度相差： 60 倍,美托洛尔血浆药物浓度与CYP2D6基因多态性的关系,Fux et al., CPT 2006,根据CYP2D6基因型调整剂量,药物 平均剂量（Mg） 调整剂量(%)单位 PM IM EM,卡维地洛 50 80 110 110美托洛尔 100 30 60 140,传统用药,个体化用药,100mg,500mg,100mg,10mg,超强代谢者,强代谢者,中等代谢者,弱代谢者,根据CYP2D6基因型选择去甲替林剂量,功能性：CYP2D6*1,功能降低：CYP2D6*2,*9, *10,*17,无功能：CYP2D6*3,*4,*6,基因缺失：CYP2D6*5,Xie HG, Personalized Medicine (2005),ALDH2*2多态影响硝酸甘油的心血管效应,*,Guo R, et al. J Am Coll Cardiol 2008,Examples of drugs “pharmacogenomic (PGX) testing proved to be benecial.,血浆Endoxifen浓度与CYP2D6基因型的关系,他莫西芬与CYP2D6,*4/*4代表CYP2D6弱代谢者，生成活性endoxifen能力降低，所以A图的无复发时间缩短，B图代表的无病生存时间也缩短。,PM由于生成活性产物Endoxifen少，复发风险增高3.3倍。,他莫西芬与CYP2D6,RF表示无复发生存率在CYP2D6 EM最高，PM或IM或HetEM都会降低，只要携带功能降低突变的合并组也降低。,2C19*17/*17纯合子超快代谢者因可产生更多4-OH-TAM，间接产生更多Endoxifen而升高疗效，导致无病生存期延长。,定义CYP2D6 EM和CYP2C19*17是导致生存期延长的有益突变，携带两个有益因素的黄色线条代表无病生存期最长，其次是携带一个有益突变，生存率最低的是2种有益突变都缺乏的患者群。,他莫西芬与CYP2D6,1325例乳腺癌患者；除EM外，IM和PM都是复发风险因子，类似肿瘤体积、淋巴结转移、癌症分期这些临床指标。,续表,Clinical Use of Pharmacogenomic Tests in 2009，Clin Biochem Rev Vol 30 May 2009,可待因与CYP2D6,62 y.o. man hospitalized for pneumoniaTreated with “standard” doses of codeine as a cough supressantComa Morphine levels 20x expected levelsCYP2D6 ultrarapid metabolizer,NEJM, 30 Dec 2004,原因分析：,可待因,经患者肝脏代谢,生成吗啡 ,呼吸抑制,死亡,药物代谢酶CYP2D6*2突变超快代谢者,可待因与CYP2D6,2. 药物转运体基因变异与药物反应实例,药物转运蛋白基因的遗传多态性倍受关注; 转运蛋白存在于细胞膜上，调节药物的吸收、分布和排泄。分两大类：三磷酸腺苷结合盒转运体超家族（ATP-binding cassette transporters，ABC转运体）和溶质转运蛋白（Solute carriers，SLC）家族。ABC超家族含约50个成员，如ABCB1(MDR1)、ABCC2 (MRP2)、ABCG2 (BCRP)。,多药耐药（multidrug resistance, MDR）基因的产物在ATP能量作用下排出细胞内底物，包括胆红素、抗肿瘤药、强心苷、免疫抑制剂、糖皮质激素等在血脑屏障脉络丛，P-糖蛋白抑制多种药物在脑中的蓄积，如地高辛、依维菌素、长春缄、地塞米松、环孢素、多潘立酮等.,P糖蛋白 (P-glycoprotein, P-gp),P-glycoprotein,2677G/T,3435C/T,ABCB1 (MDR1) 3435CT多态性,TT基因型个体地高辛的生物利用度增加,ABCB1遗传变异对底物代谢动力学的影响,多药耐药相关蛋白（multi-drug resistance protein, MRP）基因变异位点具有种族差异性。已发现 MRP1 基因 SNP 变异位点 81个、MRP2 基因 41个、MRP3 基因 30个、MRP4 基因 230个、MRP5 基因 76 个、MRP8 基因 102个和 MRP9 基因70个。,多药耐药相关蛋白(MRP),MRP 的功能：肿瘤多药耐药、药物处置。MRP2 为特异性有机离子通道蛋白，主要与铂类、依托泊甙、阿霉素、表柔比星等药物的耐药性和药物转运相关。MRP1与乳腺癌、肺癌等耐药密切相关。,药物转运体的基因变异可导致抗肿瘤药物化疗敏感性的改变,MRP1/ABCC1的过表达与肿瘤的多药耐药相关,MRP1 Arg723Gln 多态性可增加过表达MRP1细胞株对于柔红霉素、阿霉素、依托泊苷、长春新碱和长春碱的敏感性。,3.药物作用靶点基因变异与药物反应实例,影响药物效应的药物靶点基因多态性（续）,ACE的II基因型个体中ACE抑制药的效应增强,NH2,HOOC,Ser49Gly,Gly389Arg,Arg389,Gly389,Concentration of isoprenaline,Activity of cAMP (pmol/min/mg),异丙肾上腺素的1-AR激动作用与基因多态性相关,1受体基因多态性,ADRB1 haplotype and mortality during -blocker therapy in hypertension,Pacanowski MA, et al. Clin Pharmacol Ther 2008,4. 药物代谢酶和靶点基因多态性综合作用实例,华法林起始剂量和毒性反应预测,临床用药存在问题：,口服抗凝药，用于深部静脉栓塞、房颤、瓣膜置换术后的抗凝防栓，体内药物浓度个体差异大，易造成出血甚至致命。治疗指数小、抗凝不当所致的并发症困扰临床。近年来突破性明确CYP2C9多态性与华法林敏感有关。维生素K环氧化物还原酶亚基1（VKORC1)是华法林作用靶点，其启动子区1639GA多态性导致药物敏感性增加，须降低剂量以防不良反应。,CYP2C9*3纯合子病人每天只需 0.5 mg 消旋华法林，而CYP2C9野生型病人每天需 5-8 mg (相差十多倍) 才能达到相同的治疗效果。CYP2C9*3 病人在治疗之初表现更多的不良反应以及出血并发症的危险性 。华人与高加索人间的华法林维持剂量与VKORC1 -1639GA多态性间具有相关性。VKORC1变异可解释31%的维持剂量差异。,用药建议：,病人须按照以下基因型组合给予起始剂量，可预防出血并取得疗效。,WSD (mg/day) = 1.363+0.323 (VKORC1 AG) 0.33 (CYP2C9*3) + 0.618 (VKORC1 GG) - 0.005 Age + 0.288 BSA + 0.06 AVR + 0.065 Sex + 0.105 Smoking habit + 0.042 Atrial fibrillation + 0.138 Aspirin -0.152 Amiodarone2,Note：VKORC1 -1639AG, 1 = AG, 0 = AA or GG; VKORC1 -1639AA, 1 = GG, 0 = AG or AA; CYP2C9*3 allele, 1 = *3 allele carrier, 0 = *1*1; Age（year）；Sex, female =1，male = 0；Smoking habit, AVR (aortic valve replacement), Atrial fibrillation, Aspirin, Amiodarone, Thyroxine, 1 = if statement is ture, 0 = if statement is false.,华法林稳定剂量预测湘雅模型,Note: MAE, mean absolute error = the mean of (clinical observed WSD predicted WSD); Ideal prediction, predicted dose at clinical observed dose 20%; over prediction, predicted dose higher than 1.2* clinical observed dose; under prediction, predicted dose lower than 0.8* clinical observed dose.,Figure 1-2 The Q-Q chart of observed WSD and predicted WSD.,Table 1-3 Sensitive analysis of the new model,Part III：Personalized Medicine and Personalized therapy,What Is Personalized Medicine?,Personalized medicine is a rapidly advancing field of health care that promises greater precision and effectiveness than traditional medicine because it is informed by each persons unique clinical, social, genetic, genomic, and environmental information.Personalized medicine takes an integrated, coordinated, evidence-based approach to individualizing patient care across the continuum from health to disease.,急性淋巴性白血病是小儿白血病中最常见的一类基因检测可确定小儿白血病的亚型，从而有助于及时和正确的诊断根据TPMT基因型个体化给药小儿白血病治愈率由1960s的4%提高到现在的80%,基因检测和依据基因型的化疗药物治疗对小儿白血病生存率的影响,New England Journal of Medicine, 2006, 200l;,个体化给药使ALL治愈率显著提高,基因测试有助于确定小儿