CYP3A5/3A4多态性对肾移植患者术后早期他克莫司剂量的影响

目的：探索肾移植患者术后早期遗传因素与他克莫司（ FK506）个体化给药的规律,并探讨各单倍型患者在术后不同时间所需剂量的个体差异。方法：观察113例肾移植术后常规应用他克莫司+霉酚酸酯+泼尼松三联免疫抑制治疗的患者,记录术后早期（3、5、7和14 d）FK506全血谷浓度（ C0）和剂量（ D,每日每 kg 体重剂量）,测定每个患者CYP3A5及 CYP3A4基因多态性。采用酶联免疫吸附法（ELISA）监测患者术后 FK506的 C0,DNA 直接测序法测定患者CYP3A5*3、CYP3A4*18B 基因多态性。在此基础上,根据患者基因型进行分组,比较不同基因型患者 FK506的 C0、D 及C0／ D。结果：113例肾移植患者 CYP3A5*3和 CYP3A4*18B 突变等位基因发生的频率分别为73.0%和30.5%,各基因频率达到遗传平衡。CYP3A5不表达组（CYP3A5*3／*3）的 C0／ D 是 CYP3A5表达组（CYP3A5*1）的2.1~2.5倍（P ﹤0.05）;CYP3A4不表达组（CYP3A4*1／*1）的 C0／ D 是 CYP3A4表达组（CYP3A4*18B）的1.3~1.7倍（P ﹤0.05）;对于CYP3A5- CYP3A4单倍型,GG - GG 组的 C0／ D 是 AA - AA 组的2.0~2.8倍（P ﹤0.05）。各基因型患者达目标靶浓度的人数比例随术后时间延长逐步增加,而 AA - AA 组达靶浓度人数比例始终最少（ P ﹤0.05）。结论：CYP3A5*3和CYP3A4*18B基因多态性对肾移植术后 FK506的药动学有显著影响,肾移植术前可通过对患者单独进行 CYP3A5基因型的测定来确定术后早期 FK506初始剂量,从而实现个体化用药。     

肾移植受者CYP3A5基因多态性对他可莫司代谢的影响

目的研究CYP3A基因多态性对肾移植受者他可莫司代谢的影响。方法50例肾移植受者采用FK506＋霉酚酸酯＋强的松三联免疫抑制方案,FK506起始剂量0．15mg／（kg·d）,1w后根据目标血药浓度调整。CYP3A5基因多态性检测采用聚合酶链反应-限制性片段长度多态性（PCR—RFLP）方法,50例肾移植受者分为＊1／＊1型（12例）、＊1／＊3型（16例）、＊3／＊3型（22例）共3组。比较6个月内FK506的血药浓度／剂量比。结果 肾移植术后7天、1月、3月、6月＊3／＊3型患者FK506的血药浓度／剂量比显著高于＊1／＊1型和＊1／＊3型（P〈0．05）。结论由于CYP3A5基因多态性影响,＊1／＊1型组的患者早期难以达到有效FK506目标血药浓度,应该提高该组患者的起始用药剂量,根据CYP3A5基因多态性作为FK506个体化用药的依据,可以减少早期急性排斥反应,提高肾移植的临床效果。     

相关基因的遗传多态性对他克莫司疗效的影响

他克莫司(tacrolimus,FK506)广泛用于肝肾等实体器官移植术后抗排异反应治疗,然而其临床疗效具有明显的个体差异性,其中,很重要的原因就是遗传因素。因此,本文综述了CYP450酶、多药耐药基因(MDR1)、孕烷X受体(PXR)的基因多态性对FK506代谢及转运等的影响,以期为指导FK506的临床个体化用药打下理论基础。     

他克莫司的药物基因组学与个体化用药

他克莫司(FK506)是一种广泛应用的免疫抑制剂,在器官移植中发挥重要作用,由于治疗窗窄、个体间差异较大,常需要进行治疗药物监测。FK506是CYP3A酶和药物转运体P-糖蛋白(P-gp)的底物,CYP3A酶参与FK506的代谢而P-gp参与FK506的转运。这些酶的表达水平及生物活性差异可能会导致FK506个体间差异,而CYP3A及多药耐药基因(MDR1)基因多态性可能会影响CYP3A酶及P-gp的生物活性,所以CYP3A与MDR1基因多态性可能是造成FK506个体间差异的重要原因。本文就近年来FK506的药物基因组学研究进展加以综述。     

CYP3A5基因多态性与膜性肾病患者他克莫司的疗效及安全性的相关性

目的:回顾性动态分析CYP3A5基因多态性对他克莫司(FK506)血药浓度剂量体表面积比值C/D’、疗效及所致不良反应的影响,探讨FK506在不同个体、不同时期的个体化差异,以期为临床治疗提供理论性依据。方法:随访44例患者12个月的血药浓度监测以及生化检查,用荧光检测仪TL998A(天隆科技)进行基因分型,对比分析不同基因型间不同时期FK506的C/D’值、疗效及安全性的差异。结果:CYP3A5*3基因分型3个单核苷酸多态性(SNP)均符合Hardy Weinberg平衡(P>0.05);FK506初始给药剂量无显著性差异(P>0.05),但CYP3A5*3/*3型患者C/D’值显著性高于*1/*1型和*1/*3型患者(P<0.05);FK506治疗6个月及12个月时CYP3A5*3/*3型患者给药剂量显著性高于*1/*1型和*1/*3型患者(P<0.05),但C/D’值无显著性差异(P>0.05);FK506治疗12个月时CYP3A5*3/*3型患者的缓解率均高于*1/*1型和*1/*3型患者;FK506治疗过程中CYP3A5*3/*3型患者血糖异常、高尿酸发生例数高于*1/*3和*1/*1型患者。结论:CYP3A5基因多态性对膜性肾病患者C/D’有影响,治疗前检测CYP3A5基因对于确定FK506个体化给药剂量有一定的指导意义,可提高FK506疗效和安全性。     

CYP3A4/5、ABCB1基因单倍型与中国肾移植患者他克莫司血药谷浓度相关性的研究

目的:探讨CYP3A4*18B、CYP3A5*3、ABCB1基因单倍型对中国肾移植患者术后一月内他克莫司谷浓度(C0/D)的影响。方法:采用限制性片段长度多态性技术分析46名肾移植患者CYP3A4*18B、CYP3A5*3、ABCB1(外显子C1236T、G2677A/T、C3435T)基因型,采用酶增强免疫测定技术测定患者C0值。结果:经分析患者CYP3A4*18B、CYP3A5*3、ABCB1(C1236T,G2677A/T,C3435T)等位基因频率分别为0.304、0.707、0.554、0.478和0.304,均符合HardyWeinberg平衡。CYP3A4-3A5、G2677A/T-C3435T及C1236T-C3435T间均表现为连锁不平衡。术后8~15、16~30天内CYP3A4*18B与患者FK506 C0/D值显著相关,野生型患者C0/D值分别为杂合及突变型患者的1.34和1.67倍。CYP3A5*3基因也与患者FK506 C0/D值显著相关。突变型患者C0/D值在术后1~7、8~15及16~30天时分别为野生及杂合型患者的1.56、1.98及1.99倍。单倍型分析发现CYP3A4/5单倍型GG型携带者C0/D值较非携带者在移植术后8~15、16~30天显著性增加1.43、1.77倍。未观察到ABCB1基因多态性及单倍型对FK506血药浓度的影响。结论:仅CYP3A4/5单倍型与他克莫司C0/D值显著相关,移植前对CYP3A4/5单倍型进行检测将有利于他克莫司给药剂量的调整。     

CYP3A4、3A5基因多态性对肾移植患者术后他克莫司浓度/剂量比值的影响

摘 要 目的:探讨CYP3A4*18B(82266G>A,rs2242480)、CYP3A5*3(6986A>G,rs776746)位点的基因多态性对肾移植术后服用他克莫司（FK506）用药的指导作用。方法: 采用PCR RFLP(聚合酶链反应 限制性片段长度多态性)方法对280名肾移植患者进行CYP3A4*18B、CYP3A5*3基因型检测,利用化学发光微粒子免疫分析技术（CMIA）检测肾移植患者FK506血浓度,比较不同基因型患者之间FK506血药谷浓度/剂量*体质量(C₀/D)比值。 结果:280例肾移植患者中,CYP3A4*18B和CYP3A5*3基因型的突变频率分别为29.1%和69.3%。CYP3A4*18B/*18B基因型肾移植患者术后1个月,3个月FK506的C₀及C₀/D值显著低于CYP3A4*1/*1、CYP3A4*1/*18B基因型（P<0.05）。CYP3A5*3/*3基因型肾移植患者术后7日,1个月FK506的C₀及C₀/D值显著高于CYP3A5*1/*1、CYP3A5*1/*3基因型（P<0.05）。将CYP3A4*18B和CYP3A5*3进行单倍体基因型组合分析,用药后15 d、1个月,GG-GG基因型组的C₀明显高于AA-GG基因型组（P<0.05）;用药后6月,GG-GG、GA-GG、GA-AG基因型组的C₀均明显高于AA GG基因型组（P<0.05）。结论: CYP3A4*18B和CYP3A5*3基因多态性对肾移植患者的FK506血药浓度及其C₀/D值有一定影响,患者在使用FK506前进行CYP3A4*18B和CYP3A5*3基因型检测,对预测FK506用药剂量有一定的指导作用。     

基因多态性对氨氯地平药动学、药效学影响的研究进展

目的:了解基因多态性对氨氯地平药动学和药效学的影响。方法:笔者查阅近年来国内外相关文献,就药物基因组学对氨氯地平药动学和药效学的影响进行归纳和总结。结果:细胞色素P_(450)(CYP)3A、转运体多药耐药(MDR)1、L型电压依赖性钙通道C和D亚单位基因(CACNA1C和CACNA1D)、心钠素前体基因(NPPA)和G蛋白B3亚单位D等基因部分位点是影响氨氯地平药动学、药效学的重要因素。结论:基因多态性与氨氯地平药动学、药效学显著相关。     

肾移植患者CYP3A5*3基因多态性对他克莫司血药浓度/剂量比和疗效的影响

目的:研究肾移植术后患者CYP3A5*3基因多态性对他克莫司(FK506)血药浓度/剂量比(C/D)及急性排斥反应和不良反应的影响。方法:采用聚合酶链反应(PCR)和限制性内切片段长度多态性(RFLP)的方法检测肾移植患者CYP3A5*3基因型,比较不同基因型患者之间FK506的C/D值以及急性排斥反应(AR)、不良反应的差异。结果:肾移植术后1个月内,*3/*3型患者FK506的C/D值为151.7±60.0,显著高于*1/*1型和*1/*3型患者的72.6±21.7和99.4±40.3(P<0.01);移植术后3个月内*1/*1型患者AR的发生率为25.0%,显著高于*1/*3型和*3/*3型患者的10.8%和8.8%(P<0.05);而术后肝功能异常、高血糖、药物肾毒性等不良反应发生率*1/*3型和*3/*3型显著高于*1/*1型患者(P<0.05)。结论:CYP3A5*3基因多态性与肾移植患者FK506的C/D值及急性排斥反应(AR)、不良反应密切相关。     

CYP3A5、ABCB1和POR基因多态性对肾移植受者他克莫司浓度、剂量及肾功能的长期影响

目的：研究CYP3A5、ABCB1和POR基因多态性对术后3个月以上肾移植受者他克莫司（FK506）剂量、浓度以及肾功能的影响。方法：选取某院行同种异体肾移植手术的320例患者为研究对象，采用聚合酶链式反应连接的限制性片段长度多态性（PCR-RFLP）分析法和测序法检测患者CYP3A5、ABCB1和POR基因型；由于CYP3A5*3基因突变导致CYP3A5酶失活，因此将CYP3A5*3*3定义为CYP3A5非表达者（n=163），将CYP3A5*1*1和CYP3A5*1*3定义为CYP3A5表达者（n=157），比较CYP3A5表达者和非表达者间FK506血药浓度、剂量、浓度剂量比及肾小球滤过率（eGFR）的差异。结果：在移植后1、4年，CYP3A5表达的FK506血药浓度低于非表达者（P=0.0067,P=0.0004），其剂量在移植后长达8年高于非表达者（P=0.0004），而浓度剂量比则低于非表达者（P=0.0060），差异均有统计学意义。ABCB1 3435、ABCB1 1236和POR基因多态性对FK506血药浓度、剂量及浓度剂量比均无影响，差异无统计学意义（P=0.3040...     

CYP3A5和POR基因多态性对肾移植患者住院期间他克莫司浓度剂量的影响

目的：研究CYP3A5和POR基因多态性对肾移植患者住院期间他克莫司（FK506）浓度（C）、剂量（D）以及浓度剂量比（C/D）的影响。方法：以290例肾移植患者为研究对象,使用聚合酶链式反应（PCR）-限制性内切片段长度多态性（RFLP）法和测序法检测患者CYP3A5*3 A>G（rs776746）和POR*28 C>T（rs1057868）基因型,比较肾移植术后28 d内不同基因型患者之间FK506的C、D以及C/D的差异。结果：CYP3A5*3 GG型患者FK506的C和C/D在术后7、14、21、28 d均显著高于CYP3A5*3 AA型和AG型患者（P<0.01）。POR*28 CT型患者术后21 d和28 d的C/D与CC型患者相比具有显著性差异（P<0.05）,而POR*28基因型对其他各时间点FK506的C、D以及C/D均无影响。根据CYP3A5*3基因分层后发现,POR*28基因多态性对CYP3A5*3 AA型患者FK506的C、D以及C/D影响最大,其次是CYP3A5*3 AG型,而对CYP3A5*3 GG型患者各时间点的C、D以及C/D均无影响。在CYP3A5*3 AA型患者中,术后各时间点POR*28 CC型FK506的D均低于CT和TT型患者,CC型患者的C/D均高于CT型和TT型,且在多个时间点处有统计学差异。结论：肾移植初期,CYP3A5*3和POR*28基因多态性对FK506的浓度剂量有影响,且POR*28基因多态性对CYP3A5*3 AA型患者FK506浓度剂量的影响最大。     

CYP3A4*18B基因多态性与他克莫司血药浓度的相关性研究

目的:探讨中国汉族肾移植患者CYP3A 4* 18B基因型对术后1个月内他克莫司谷浓度的影响.方法:采用限制性片段长度多态性技术分析了30例汉族患者CYP3A4* 18B基因型,采用酶增强免疫测定技术测定患者他克莫司谷浓度.将血药浓度标准化后对不同基因型患者剂量调整谷浓度差异进行t检验.结果:测得CY P3A 4*18B等位基因频率为0.333,符合Hardy-Weinberg平衡.将患者分成*1/*1型慢代谢组和*1/*18B合并*18B/*18B型快代谢组,两组标准化谷浓度分别为(98.02±18.56) ng·kg·mL-1· mg-1和(62.91±18.15) ng· kg· mL-1· mg-1 (P＜0.01),慢代谢组的FK506剂量调整谷浓度显著高于快代谢组.结论:CYP3A 4* 18B基因多态性与他克莫司剂量调整谷浓度显著相关,该突变可能导致CYP3A4酶活性的提高.     

环孢素A药动学/药效学/不良反应的影响因素分析

目的：对影响环孢素A药动学、药效学、不良反应的药物因素及遗传因素进行分析。方法：主要查阅Pubmed、Embase及中国期刊全文数据库2010-2016年载录的相关文献,归纳总结出具体的影响因素。结果：药物因素（血药浓度、给药频率、合并用药等）及遗传因素（CYP3A和MDR1基因多态性等）对环孢素A药动学、药效学、不良反应均有影响。结论：基因多态性、合并用药为环孢素A药动学、药效学、不良反应的主要影响因素,临床上需结合患者实际情况进行监测以保证合理的个体化给药和用药安全。     

MDR1基因多态性和单倍体对肾移植术后稳定期患者他克莫司浓度/剂量比值的影响

目的 探讨MDR1 C1236T、G2677T/A和C3435T 基因多态性和单倍体对中国汉族肾移植术后稳定期患者他克莫司浓度/剂量比值的影响,为他克莫司个体化用药提供依据。方法 采用PCR-基因测序法检测104例肾移植术后稳定期患者MDR1 C1236T、G2677T/A和C3435T 的基因多态性,采用均相酶免疫测定方法(EMIT法)测定他克莫司的谷浓度,比较不同基因型患者之间他克莫司血药浓度/(剂量×体质量)(C/D)比值。结果 104例患者中,MDR1 C1236T、G2677T/A和C3435T突变频率分别为56.73%、55.77%和33.17%。MDR1 C3435T、MDR1 TTT单倍体与他克莫司C/D比值具有相关性(P<0.05)。CYP3A5*3*3患者中,MDR1 TTT单倍体与他克莫司C/D比值仍存在显著相关(P<0.05)。MDR1 C1236T、G2677T/A、CGC单倍体与他克莫司C/D比值无显著性差异(P>0.05)。结论 MDR1 C3435T、MDR1 TTT单倍体与中国汉族肾移植术后稳定期患者他克莫司C/D比值具有显著相关性,是影响肾移植患者他克莫司浓度个体化差异的重要因素。     

Association of MDR1, CYP3A4*18B, and CYP3A5*3 polymorphisms with cyclosporine pharmacokinetics in Chinese renal transplant recipients

Objective  The objective of this study was to retrospectively evaluate the effects of MDR1, CYP3A4*18B, and CYP3A5*3 genetic polymorphisms on cyclosporine A (CsA) pharmacokinetics in Chinese renal transplant patients during the first month after transplantation. Methods  A total of 103 renal transplant recipients receiving CsA were genotyped for MDR1 (C1236T, G2677T/A, and C3435T), CYP3A4*18B, and CYP3A5*3. The predose and 2-h postdose concentrations of CsA (C₀ and C₂, respectively) were determined by fluorescence polarization immunoassay, and their relationships with corresponding genotypes and haplotypes were investigated. Results  Patients with a CYP3A4*1/*1 genotype were found to have a higher dose-adjusted concentration compared with those with CYP3A4*18B/*18B, as follows: for C₂, 19.3% (P = 0.008) during days 8-15, 35.2% (P = 0.008) during days 16–30, and for C₀, 39.7% (P = 0.012) during days 16–30. The dose-adjusted C₀ was higher in patients with MDR1 1236CC compared with those with 1236TT in the first month postoperation. The dose-adjusted C₀ in patients with the CYP3A5*3/*3 genotype was 25.5% and 30.7% higher than those with the wild-type genotype during days 8–15 (P = 0.011) and days 16–30 (P = 0.015), respectively. Haplotype analysis revealed that the dose-adjusted C₀ was higher in the first month following surgery in carriers of haplotype MDR1 CAC than in noncarriers. Polymorphisms of MDR1 and CYP3A5*3 did not affect dose-adjusted C_2. Conclusion  The data suggests that the CYP3A4*18B genotype affects CsA pharmacokinetics during the first month following surgery in Chinese renal transplant recipients. Patients with CYP3A4*18B alleles may require higher doses of CsA to reach the target levels. Large prospective studies may be needed to further explore the impact of MDR1 and CYP3A5*3 polymorphisms on CsA pharmacokinetics in renal transplant recipients.     

CYP3A5和MDR1基因型对尿毒症患者肾移植术后早期他克莫司血药浓度和肌酐水平的影响

目的 评价真实临床实践中CYP3A5(CYP3A5*3,6986A>G)及MDR1(C3435>T,G2677>T/A,C1236>T)基因多态性对尿毒症患者接受肾移植术后早期他克莫司血药浓度的影响及其最佳治疗浓度.方法 以入选2013～2017年单中心的131例首次肾移植术且术后以他克莫司为基础进行三联免疫治疗的患者...     

Effects of genetic polymorphisms on the pharmacokinetics of calcineurin inhibitors.

PURPOSE: The effects of genetic polymorphisms on the pharmacokinetics of calcineurin inhibitors were examined. SUMMARY: The bioavailability and metabolism of cyclosporine and tacrolimus are primarily controlled by efflux pumps and members of the cytochrome P-450 (CYP) isoenzyme system found in the liver and gastrointestinal tract. The number and severity of adverse effects from these drugs are related to the overall exposure, measured by length of therapy and blood drug concentration. One contributing factor to the inconsistent pharmacokinetics of calcineurin inhibitors may be variable expression of functional CYP3A4, CYP3A5, and P-glycoprotein (PGP) efflux pumps, which may be the result of single-nucleotide polymorphisms found on the genes encoding for CYP3A4, CYP3A5, and PGP. CYP3A5*3 and CYP3A5*6 are the most common polymorphisms of CYP3A5. Using genetic markers to adjust initial doses of cyclosporine or tacrolimus may prove difficult, considering the variety of polymorphism known to affect CYP3A4, CYP3A5, and the multidrug resistance-1 (MDR1) gene (the gene that codes for PGP). Studies have found that carriers of CYP3A5*1 consistently have higher clearance rates of tacrolimus than do CYP3A5*3 homozygotes. The influences of CYP3A5 alleles on cyclosporine metabolism and the MDR1 C3435T polymorphism on tacrolimus metabolism remain controversial. CONCLUSION: For renal transplant recipients receiving tacrolimus as an immunosuppressant, practitioners can expect CYP3A5*1 carriers to have a tacrolimus clearance 25-45% greater than that of CYP3A5*3 homozygotes, with proportional dosing needs to maintain adequate immunosuppression. Since inadequate immunosuppression is linked to graft rejection, evaluation of CYP3A5 polymorphisms may be helpful in determining an appropriate starting dosage, rapidly achieving adequate immunosuppression, and ultimately improving the outcome of renal transplantation.     

MDR1 haplotypes derived from exons 21 and 26 do not affect the steady-state pharmacokinetics of tacrolimus in renal transplant patients

AIM: This retrospective study investigated the influence of MDR1 haplotypes derived from the polymorphisms 2677G > T (exon 21) and 3435C > T (exon 26) on the pharmacokinetics of the immunosuppressant drug tacrolimus in 73 renal transplant patients. METHODS: Based on both variants of SNPs 2677 and 3435, four different haplotypes and eight different genotypes were identified in the study sample. Tacrolimus trough concentrations (C(0)) were compared between different SNP variants and genotypes, as well as between carriers and noncarriers of each haplotype. Additionally, CYP3A5 genotype (6956G > A) was determined. RESULTS: No significant differences were observed between groups. Differences in mean tacrolimus C(0) values between carriers and noncarriers of each haplotype ranged from -0.04 microg/litre (95% confidence interval: -0.53 to 0.60) to -23 microg/litre (-1.07 to 1.53). No association was found between CYP3A5*1/*3 genotype and tacrolimus Co concentractions. CONCLUSION: MDR1 haplotypes derived from the SNPs 2677G > T (exon 21) and 3435C > T (exon 26) do not influence the pharmacokinetics of tacrolimus in renal transplant patients.     

Pharmacogenetics of MDR1 and its impact on the pharmacokinetics and pharmacodynamics of drugs

The multi-drug resistant transporter MDR1/P-glycoprotein, the gene product of MDR1, is a glycosylated membrane protein of 170 kDa, belonging to the ATP-binding cassette (ABC) superfamily of membrane transporters. MDR1 was originally isolated from resistant tumor cells as part of the mechanism of multi-drug resistance, but over the last decade, it has been elucidated that human MDR1 is also expressed throughout the body to confer intrinsic resistance to the tissues by exporting unnecessary or toxic exogeneous substances or metabolites. A number of various types of structurally unrelated drugs are substrates for MDR1, and MDR1 and other transporters are recognized as an important class of proteins for regulating pharmacokinetics and pharmacodynamics. In 2000, Hoffmeyer et al. performed a systemic screening for MDR1 polymorphisms and indicated that a single nucleotide polymorphism (SNP), C3435T in exon 26, which caused no amino acid change, was associated with the duodenal expression of MDR1 and thereby the plasma concentrations of digoxin after oral administration. Interethnic differences in genotype frequencies of C3435T have been clarified, and, at present, a total of 28 SNPs have been found at 27 positions on the MDR1 gene. Clinical studies on the effects of C3435T on MDR1 expression and function in the tissues, and also on the pharmacokinetics and pharmacodynamics have been performed around the world; however, there are still discrepancies in the results, suggesting that the haplotype analysis of the gene should be included instead of SNP detection, and the design of clinical trials must be carefully planned to avoid misinterpretations. A polymorphism of C3435T is also reported to be a risk factor for a certain class of diseases such as the inflammatory bowel diseases, Parkinson's disease and renal epithelial tumor, and this might also be explained by the effects on MDR1 expression and function. In this review, the latest reports are summarized for the future individualization of pharmacotherapy based on MDR1 genotyping.