ABCB1基因多态性与丙戊酸钠治疗癫痫疗效的相关性研究

目的探究ABCB1基因多态性与丙戊酸钠治疗癫痫疗效的相关性。方法选取我院2016年8月～2017年8月收治的140例癫痫患者进行对比调查,依据患者的治疗效果分组,对ABCB1基因多态性与丙戊酸钠治疗癫痫疗效做相关性分析。结果两组患者基因型与等位基因做遗传平衡检验,3个单核苷酸多态性均符合Hardy-Weinberg比例(P> 0.05);不同分型组患者丙戌酸钠体内浓度均未见明显差异;ABCB1基因多态性中不同基因型分布频率分布情况对治疗效果具有影响作用,其中C1236T中集中分布与TT与CC整体治疗效果更佳,C3435T各分型并不会影响到治疗效果,G2677T/A中集中分布在GG与GT治疗效果更为理想。结论研究结果证实ABCB1基因多态性对丙戊酸钠的血药浓度并不存在显著影响,但对于丙戊酸钠治疗癫痫的效果具有一定影响作用,其中C1236T与G2677T/A中基因型分布影响作用最为明显。     

ABCB1基因多态性对肾移植受者环孢素血浓度的影响

目的:研究肾移植术后患者ABCB1基因多态性对环孢素（CsA）血浓度的影响。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339名服用CsA的肾移植患者进行ABCB1基因1236C>T、2677G>T/A和3435C>T多态性检测,荧光偏振免疫法检测肾移植患者CsA血浓度。结果:在339名肾移植患者中,ABCB1基因1236C>T、2677G>T/A和3435C>T突变等位基因频率分别为64.25%、51.54%和35.75%。ABCB1 1236C>T基因多态性检测显示,在移植术后1年,CC基因型个体的CsA血谷浓度明显高于CT和TT基因型个体（P<0.05）。2677G>T/A基因多态性检测提示,在移植术后7d,杂合子GA+GT基因型携带者的C₀高于GG和AA+TT+AT基因型携带者（P<0.05）。3435C>T基因多态性检测表明:在移植术后3个月,突变纯合子TT基因型携带者的C₀低于CC和CT基因型携带者（P<0.05）。其余各时间点,上述3种基因多态性对CsA血谷浓度无明显影响（P>0.05）。结论:ABCB1基因1236C>T、2677G>T/A和3435C>T多态性对极少数时间点的CsA浓度有影响,但对绝大多数时间点的环孢素浓度无影响。     

C1236T、 G2677T/A 和C3435T 基因多态性与乳腺癌分子分型的关系及意义

摘要： 目的 观察多药耐药基因 1 （MDR1） 第 12、 21 及 26 外显子 C1236T、 G2677T/A 和 C3435T 基因多态性在乳腺癌患者外周血中的分布, 分析其与分子分型的关系。方法 应用高分辨熔解曲线 （HRM） 技术检测 400 例乳腺癌患者 C1236T、 G2677T/A 及 C3435T 基因多态性。采用 Hardy-Weinberg 遗传平衡检验进行基因型分布遗传平衡吻合度检验。参照 2013 年 St.Gallen 国际专家乳腺癌分子分型共识。分析乳腺癌患者中 C1236T、 G2677T/A 和 C3435T 基因型分布特点, 并探讨其与分子分型的关系。结果 （1）400 例乳腺癌患者中 C1236T、 G2677T/A 和 C3435T 中分别有 2 例、 3 例和 2 例标本未得出基因分型结果, C1236T 位点 CC、 CT 和 TT 基因型分别占 16.08% （64/398）、 44.22% （176/398） 和 39.70% （158/398）; G2677T/A 位点 GG、 GT、 GA、 TT 和 AT 基因型分别占 16.62% （66/397）、 44.33% （176/ 397）、 7.05% （28/397）、 27.46% （109/397） 和 4.54% （18/397）; C3435T 位点 CC、 CT 和 TT 基因型分别占 21.11% （84/ 398）、 56.03% （223/398） 和 22.86% （91/398）。经 Hardy-Weinberg 遗传平衡检验, 认为 C1236T、 G2677T/A 和 C3435T 基因多态性具有群体代表性 （P > 0.05）。（2） 分子分型显示, 11例人类表皮生长因子受体2 （HER-2, 2+） 患者未行荧光原位杂交 （FISH） 检测予以剔除, 其中Luminal A型占41.90% （163/389）, Luminal B型占32.65% （127/389）, HER-2过表达型占13.62% （53/389）, 三阴型占11.83% （46/389）。（3） C3435T位点CT/TT基因型在Luminal A型患者中的频率高于其在HER-2过表达型和三阴型患者中的频率 （χ2 =12.011, P=0.001; χ2 =13.976, P < 0.001）, C1236T和G2677T/A基因多态性在不同分子分型中的分布差异无统计学意义 （P > 0.05）。结论 MDR1基因C3435T位点多态性可以为乳腺癌异质性提供更合理的补充, 不同乳腺癌分子分型患者中CT/TT基因表型可能对药物治疗更敏感。     

CYP3A5和ABCB1基因多态性对肾移植患者术后初期他克莫司剂量、浓度及肾功能的影响

目的研究CYP3A5和ABCB1基因多态性对肾移植患者术后初期他克莫司剂量、浓度以及肾功能的影响。方法以200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和ABCB1(C1236T、G2677T/A、C3435T)基因型,比较肾移植术后28 d内不同基因型患者之间他克莫司血药浓度(C)、剂量(D)、浓度剂量比(C/D)以及肾功能(血清肌酐和胱抑素C水平)的差异。结果 CYP3A5非表达组(CYP3A5*3*3型)的C和C/D在术后7、14、21和28 d均显著高于CYP3A5表达组(CYP3A5*1*1和CYP3A5*1*3型)(P <0.05,P<0.01)。ABCB1 1236基因多态性对CYP3A5表达组患者的他克莫司C、D及C/D均没有显著影响;对于CYP3A5非表达组,ABCB1 1236 CT和TT型患者他克莫司的D及C/D有显著性差异。对于CYP3A5表达组,ABCB1 3435 TT型患者他克莫司的C和D显著低于CC型和CT型患者(P <0.05);而在CYP3A5非表达组中,ABCB1 3435 TT型患者的他克莫司D显著低于CT型。对肾功能的影响:ABCB11236和2677基因型对CYP3A5表达组和非表达组肾功能均没有显著影响。对于CYP3A5非表达组,ABCB1 3435 TT型患者移植后第7或14日肌酐和胱抑素C水平显著高于CC和CT型患者(P <0.05)。结论肾移植术后初期,CYP3A5*3、ABCB1 C1236T和ABCB1 C3435T基因多态性影响他克莫司C和D,ABCB1 C3435T基因多态性对肾功能有影响。     

肾移植中环孢素的血药浓度与多药耐药基因多态性的关系

目的 探讨肾移植术后患者的MDR1C3435T、G2677T/A和C1236T位点的基因多态性对环孢素(CsA)血药浓度的影响.方法 使用荧光偏振免疫分析法(AxsYM)测定65例肾移植患者在术后1 wk和1 mo时的CsA血药浓度(包括峰浓度ρ2和谷浓度ρ0),使用等位基因特异扩增法(ASA-PCR)对患者进行MDR1基因分型,比较不同基因型之间CsA浓度剂量比的差异.结果 在65例患者中,C3435T,CC型25例(38.5%),CT型35例(53.8%),TT型5例(7.7%);G2677T/A,GG型15例(23.1%),GT型21例(32.3%),TT型10例(15.4%),GA型12例(18.5%),AT型6例(9.2%),AA型1例(1.5%);C1236T,CC型10例(15.4%),CT型32例(49.2%),TT型23例(35.4%).C3435T的CT型患者的CsA浓度剂量比略大于CC型和TT型;G2677T/A的从型患者的CsA浓度剂量比略大于其他基因型;C1236T的TT型患者的谷浓度剂量比略大于CC型和CT型,CC型患者的峰浓度剂量比略大于CT型和TT型,但差异均无统计学意义(P＞0.05).结论 在肾移植患者中,MDR1多态性与CsA血药浓度无明显相关性,有待进一步确认.     

江苏地区汉族儿童多药耐药基因3个单核苷酸多态性位点的单倍型研究

目的 分析江苏汉族人群多药耐药基因-1(MDR1)的单核甘酸多态(12外显子1236 C→T突变、21外显子2677G→T/A突变、26外显子3435C→T突变)及其构成的单倍型分布.方法 通过多重单碱基延伸反应(SNaPshot SNP分型技术)对江苏地区170名健康儿童的MDR1 C1236T、G2677T/A、C3435T的SNP位点进行基因分型,统计各基因型频率.UNPHASED软件对MDR1的SNPs(C1236T-G2677T/A-C3435T)进行单倍型分析.结果 在170例儿童中,等位基因1236T、2677T、2677A、3435T频率分别为63.5%、37.4%、17.0%和35.0%.基因型频率分布符合Hardy-Weinberg平衡(HWE),差异无统计学意义(P>0.05).MDR1的1236、2677、3435三个位点间(C1236T-G2677T/A-C3435T)存在连锁不平衡性,以TTT(31.8%)、TGC(25.3%)、CGC(17.7%)和CAC(16.2%)四种单倍型为主.结论 江苏地区汉族人群MDR1的单核甘酸多态及单倍型分布具有自己的特点.在临床应用相关药物时,进行基因型及单倍型检测,将有助于指导临床个体化用药.     

ABCB1 3435C>T基因多态性对急性淋巴细胞白血病患儿大剂量甲氨蝶呤血药浓度及不良反应的影响

摘 要 目的：研究急性淋巴细胞白血病（ALL）患儿多药耐药基因1（ABCB1）基因多态性与使用大剂量甲氨蝶呤（MTX）化疗期间的血药浓度及不良反应的关系。方法: 70例ALL患儿外周血,提取DNA,采用PCR技术和直接测序的方法分析ABCB1基因的基因型;采用酶放大免疫法（EMIT）测定MTX给药后48h的血药浓度;2.华中科技大学同济医学院同济医院药学部,统计不良反应相关信息。分析ABCB1基因多态性与MTX血药浓度及不良反应的关系。结果: ABCB1 C3435T位点存在多态性,ABCB1 C3435T位点患儿CC、CT和TT基因型的分布频率分别为31.43%,47.14%,21.43%。ABCB1 C3435T位点各基因型MTX 48h C/D值由低到高依次为CC型患儿、CT型患儿、TT型患儿,其中TT型与CC型之间差异具有统计学意义(P＜0.05)。ABCB1 C3435T位点不同基因型患者中,口腔黏膜损害、肝脏损害发生率差异有统计学意义（P＜0.05）。结论:ABCB1 C3435T位点基因多态性与ALL患儿大剂量MTX化疗后的血药浓度及不良反应（口腔黏膜炎、肝脏损害）有关。     

肝移植中他克莫司的血药浓度与多药耐药基因多态性的关系

目的探讨肝移植术后患者的多药耐药基因（MDR1）C3435T、G2677T／A和C1236T位点的基因多态性对他克莫司（F1〈506）血药浓度的影响。方法使用荧光偏振免疫分析法（AxSYM）测定42例肝移植患者在术后1周和1个月时FK506的血药浓度,使用等位基因特异扩增法（ASA-PCR）对患者进行MDR1基因分型,比较不同基因型之间FK506的浓度／剂量比的差异。结果在42例患者中,C3435T中CC型16例（38．1％）,CT型23例（54．8％）,TT型3例（7．1％）;G2677T／A中CA;型4例（9．5％）,GT型13例（31．O％）,TT型8例（19．0％）,GA型7例（16．7％）,AT型10例（23．8％）;C1236T中CC型6例（14．3％）,CT型19例（45．2％）,TT型17例（40．5％）。根据移植术后第1周和第1个月的记录,在C1236T中CC型患者的浓度／剂量比小于CT型和TT型,且差异有统计学意义（P〈0．05）。在C3435T和G2677T／A中不同基因型之间的浓度／剂量比的差异无统计学意义（P〉0．05）。结论在肝移植患者中MDR1多态性与FK506血药浓度具有相关性,C1236TCC型患者拟取得相似的血药浓度要比CT型和TT型患者服用更高剂量的FK506。     

CYP3A5和MDR1基因多态性对中国肝移植患者他克莫司药动学的影响

目的探讨细胞色素P450酶3A5（CYP3A5）基因和多药耐药基因（MDR1）C1236T、G2677T／A、C3435T多态性对肝移植患者口服他克莫司（TAC）后体内药动学参数的影响。方法采集28例肝移植患者手术后第1周和第3周血标本,采用LC—MS／MS法检测TAC血药浓度,计算主要药动学参数。采用聚合酶链反应结合基因测序分析28例肝移植患者CYP3A5＊3和MDR1主要基因型。结果携带MDR1 3435T基因型的肝移植患者口服TAC后,药动学参数AUC0→1和ρmax明显高于3435CC型患者,而CYP3A5＊3、MDR1 C1236T和G2677T／A基因多态性对TAC的药动学参数无明显影响。结论携带MDR1 3435T基因型肝移植患者比3435CC型患者需要较高剂量才能达到目标浓度。     

江苏地区汉族儿童多药耐药基因3个单核苷酸多态性位点的单倍型研究

目的分析江苏汉族人群多药耐药基因-1（MDR1）的单核甘酸多态（12外显子1236C→T突变、21外显子2677G→T/A突变、26外显子3435C→T突变）及其构成的单倍型分布。方法通过多重单碱基延伸反应（SNaPshotSNP分型技术）对江苏地区170名健康儿童的MDR1C1236T、G2677T/A、C3435T的SNP位点进行基因分型,统计各基因型频率。UNPHASED软件对MDR1的SNPs（C1236T-G2677T/A-C3435T）进行单倍型分析。结果在170例儿童中,等位基因1236T、2677T、2677A、3435T频率分别为63.5%、37.4%、17.0%和35.0%。基因型频率分布符合Hardy-Weinberg平衡（HWE）,差异无统计学意义（P〉0.05）。MDR1的1236、2677、3435三个位点间（C1236T-G2677T/A-C3435T）存在连锁不平衡性,以TTT（31.8%）、TGC（25.3%）、CGC（17.7%）和CAC（16.2%）四种单倍型为主。结论江苏地区汉族人群MDR1的单核甘酸多态及单倍型分布具有自己的特点。在临床应用相关药物时,进行基因型及单倍型检测,将有助于指导临床个体化用药。     

Association analysis of three ABCB1 (MDR1) gene variants (C1236T,G2677A/T and C3435T) and their genotype/haplotype combinations with the familial Mediterranean fever

Abstract

1. Familial Mediterranean fever (FMF) is considered an autosomal recessive disorder, associated with a single gene named Mediterranean fever (MEFV). The aim of this study was to perform genotyping and haplotyping analysis of the multidrug resistance (ATP-binding cassette, subfamily B, member 1 – ABCB1) gene in FMF patients.

2. Three ABCB1 gene polymorphisms (C1236T, G2677T/A and C3435T) were analyzed in 309 FMF patients and 250 healthy control subjects. All subjects were genotyped by PCR–restriction fragment length polymorphism analysis, and statistical analysis was performed using the Arlequin 3.1.1 and SPSS 16.0 software packages.

3. The CT genotype frequency of the C3435T polymorphism (p?=?0.003), the CT–GT–CT (C1236T–G2677T/A–C3435T) triple genotype (p?=?0.001) and the C–G (C1236T–G2677T/A) haplotype (p?=?0.030) were more common in the FMF patients. The CT–GG–CC triple genotype and T–G–C, C–T–T and T–G–T haplotypes (C1236T–G2677T/A–C3435T) were higher in the control subjects (p?=?0.011, 0.001, 0.009 and 0.000, respectively). The CT–GG binary genotype and C–T and T–G haplotypes for C1236T–G2677T/A polymorphisms may have a high degree of protective effect against FMF (p?=?0.0005, 0.002 and 0.000, respectively).

4. Our study showed that genotypes and haplotypes of ABCB1 gene polymorphisms may affect patients’ FMF susceptibility.     

ABCB1 C3435T and G2677T/A polymorphism decreased the risk for steroid-induced osteonecrosis of the femoral head after kidney transplantation

Advances in transplantation technology have brought about great benefits to patients suffering from organ failure, but the problem still remains of complications induced by steroids used for post-transplant immunosuppression. Among the side-effects caused by steroids, non-traumatic osteonecrosis of the femoral head (ONF) constitutes a serious problem. The same protocol for steroid administration induces ONF in some patients, but not in others, indicating the presence of individual difference in steroid sensitivity. We hypothesized that this difference might be mediated by the drug-transport protein, P-glycoprotein (P-gp), and investigated the relationship between single nucleotide polymorphisms in the multidrug resistance gene 1 (ABCB1, MDR1) encoding P-gp and ONF. Subjects comprised 136 patients receiving kidney transplantation. Thirty patients developed post-transplant ONF. Genomic DNA was extracted from peripheral blood, and genotypes of ABCB1 C3435T (exon 26) and G2677T/A (exon 21) were determined by direct sequencing. Multivariate analyses based on clinical information were performed to determine the relationship between ABCB1 genotypes and ONF. The dose/concentration (D/C) ratios of tacrolimus were also determined to estimate the activity of P-gp in patients with different genotypes of ABCB1 C3435T (CC, CT, TT), and in those who did and did not develop ONF. The ABCB1 3435TT genotype showed a significantly lower incidence of ONF (adjusted odds ratio = 0.10, P = 0.034). The D/C ratio in the 3435TT genotype was significantly higher than that in the 3435CC genotype. The D/C ratio in patients developing ONF was significantly higher than in those patients who did not develop ONF. The results suggest increased activity of P-gp in patients with the 3435TT genotype and in those who did not develop ONF. The ABCB1 2677 homozygous variant type also showed a lower incidence of ONF (adjusted odds ratio = 0.26, P = 0.056). The 3435T and 3435C alleles were in linkage disequilibrium with the 2677T and the 2677G alleles, respectively, in the study population. An assessment of C3435T and G2677T/A polymorphisms preceding steroid treatment could be useful for predicting the resistance to ONF development.     

Effect of ABCB1 (MDR1) 3435C >T and 2677G >A,T polymorphisms and P-glycoprotein inhibitors on salivary digoxin secretion in congestive heart failure patients

The aim of the present study was to evaluate the effects of ABCB1 ( MDR1 ) gene polymorphism on P-glycoprotein model substrate, i.e. digoxin, salivary secretion. The study was carried out in 77 patients diagnosed with congestive heart failure administered digoxin, who were subdivided into two groups: 1) co-administered P-glycoprotein inhibitors and 2) without any known P-glycoprotein inhibitors. The ABCB1 2677G >A,T and 3435C >T polymorphisms were evaluated using PCR-RFLP methods. Steady-state digoxin concentrations were measured in blood serum as well as in unstimulated and stimulated saliva using FPIA method. It was found that values of Pearson's coefficient were significantly higher in patients co-administered P-glycoprotein inhibitors in comparison with subjects who were not administered any inhibitor both for stimulated (Pearson's coefficient r = 0.832, p < 0.01) and unstimulated saliva (r = 0.812, p < 0.01). Evaluation of the impact of ABCB1 2677G >A,T and 3435C >T polymorphism on salivary digoxin secretion revealed significant differences in digoxin stimulated saliva/serum ratio between patients stratified by 2677G >A,T genotype (TT, TA> GT, GA> GG, p < 0.01). The results from the present study suggest that administration of P-glycoprotein inhibitors as well as ABCB1 gene polymorphism may affect salivary digoxin secretion.     

Relationship between the C3435T and G2677T(A) polymorphisms in the ABCB1 gene and P-glycoprotein expression in human liver

AIMS: The aim of the study was to determine whether a correlation exists between MDR1 (ABCB1) gene polymorphisms at positions 3435 (C3435T) and 2677 (G2677T(A)) and the expression of human hepatic P-glycoprotein (P-gp). METHODS: P-gp protein expression in 26 human livers was assessed by Western blotting and ABCB1 mRNA expression was determined by real time RT-PCR. The C3435T and G2677T(A) polymorphisms were identified by RFLP and direct sequence analysis, respectively. RESULTS: The C and G allele frequencies for the C3435T and G2677T(A) polymorphisms were 0.48 and 0.79, respectively, and the genotypes were in Hardy-Weinberg equilibrium. There was a 200- and 20-fold variation in the expression of ABCB1 mRNA and Pgp protein expression, respectively. There were no differences in mRNA and protein expression identified amongst the different genotypes attributable to the C3435T and G2677T(A) polymorphisms in the ABCB1 gene. Exposure to a PXR ligand prior to death did not influence mRNA or protein expression. CONCLUSIONS: There is substantial variability in the expression of Pgp in human liver, but this is not due to the presence of C3435T and G2677T(A) polymorphisms in the ABCB1 gene, although our study is limited by a small sample size.     

Cytochrome P450 and ABCB1 genetics: association with quetiapine and norquetiapine plasma and cerebrospinal fluid concentrations and with clinical response in patients suffering from schizophrenia. A pilot study

Variability in response to atypical antipsychotic drugs is due to genetic and environmental factors. Cytochrome P450 (CYP) isoforms are implicated in the metabolism of drugs, while the P-glycoprotein transporter (P-gp), encoded by the ABCB1 gene, may influence both the blood and brain drug concentrations. This study aimed to identify the possible associations of CYP and ABCB1 genetic polymorphisms with quetiapine and norquetiapine plasma and cerebrospinal fluid (CSF) concentrations and with response to treatment. Twenty-two patients with schizophrenia receiving 600?mg of quetiapine daily were genotyped for four CYP isoforms and ABCB1 polymorphisms. Quetiapine and norquetiapine peak plasma and CSF concentrations were measured after 4 weeks of treatment. Stepwise multiple regression analysis revealed that ABCB1 3435C?>?T (rs1045642), 2677G?>?T (rs2032582) and 1236C?>?T (rs1128503) polymorphisms predicted plasma quetiapine concentrations, explaining 41% of the variability (p?=?0.001). Furthermore, the ABCB1 polymorphisms predicted 48% (p?=?0.024) of the variability of the Δ PANSS total score, with the non-carriers of the 3435TT showing higher changes in the score. These results suggest that ABCB1 genetic polymorphisms may be a predictive marker of quetiapine treatment in schizophrenia.     

Polymorphisms of the ABCB1 gene are associated with the therapeutic response to risperidone in Chinese schizophrenia patients

P-glycoprotein, a product of the ATP-binding cassette B1 (ABCB1) gene, plays an important role in absorption and distribution of drugs. The brain entry of risperidone and 9-OH-risperidone is greatly limited by P-glycoprotein, which implies that the functional polymorphisms of ABCB1 in humans may be a factor contributing to the variability in response to risperidone. The present study was therefore designed to examine whether polymorphisms of the ABCB1 gene are related to therapeutic response. For this purpose, 130 Chinese schizophrenia patients undergoing risperidone treatment were recruited. Plasma drug concentrations were monitored and clinical symptoms were evaluated using the Brief Psychiatric Rating Scale (BPRS) before and 8 weeks after the treatment. Association tests between genotypes and percentage improvement in total BPRS scores were performed using analyses of variance. Our results show that genotyping C1236T may help to predict the efficacy of risperidone treatment on the basis that patients with the TT genotype showed greater improvement than those with other genotypes on the overall BPRS (F = 3.967, p = 0.021), while other polymorphisms, including rs13233308, G2677T/A and C3435T polymorphism, did not show any association with the response to risperidone. These results showed suggestive evidence that genetic variation in the ABCB1 gene may influence the individual response to risperidone.     

CYP3A5、ABCB1基因多态性对中国肾移植患者服用他克莫司剂量和血药浓度的影响

目的：研究肾移植患者CYP3A5、ABCB1基因多态性对肾移植术后患者他克莫司（TAC）血药浓度及给药剂量的影响。方法：采集83例中国肾移植患者术后3个月内TAC的常规监测的谷浓度（C0）。测定受试者CYP3A5*3（rs776746）、ABCB1 1236C＞ T（rs1128503）、2677G＞ T/A（rs2032582）、3435C＞ T（rs1045642）位点的基因型，分析基因多态性对TAC的C0、剂量的影响。结果：患者CYP3A5、ABCB1基因型频率均符合Hardy-Weinberg平衡（P ＞ 0.05）。在移植后3个月期间，CYP3A5*3/*3型患者相较于携带*1等位基因患者，具有更高的C0和更低的剂量（P ＜ 0.05）。ABCB1 2677GG基因型的C0显著低于GT、GA、AA、TT、AT型（P ＜ 0.05）；3435CT型的C0显著高于CC、TT型（P ＜ 0.05）。根据ABCB1的单倍型进行分组，并与CYP3A5进行了联合分析，结果发现，发现CYP3A5*1/*1与*1/*3组与*3/*3组中，不同ABCB1单倍型对TAC血药浓度影响的差异无统计学意义。术后随时间延长，CYP3A5*3/*3型患者的TAC剂量逐步降低，而携带*1基因患者的剂量则呈增加趋势。结论：CYP3A5比ABCB1基因多态性对肾移植受者TAC血药浓度的影响更显著，若达到相同的血药浓度，CYP3A5*3/*3型患者每日所服用的剂量更低。根据CYP3A5基因型制定给药方案，有助于尽早达到浓度标准，达到精准治疗的目标。     

MDR1 haplotype frequencies in Japanese and Caucasian, and in Japanese patients with colorectal cancer and esophageal cancer

The genotype frequencies of MDR1 T-129C, C1236T, G2677A,T and C3435T SNPs were compared in 154 healthy Japanese and 100 healthy Caucasians to provide basic information on the inter-ethnic differences of pharmacotherapeutic outcome. The variants were found at allelic frequencies of 5.5%, 65.6%, 16.6%, 40.6% and 40.6%, for T-129C, C1236T, G2677A, G2677T and C3435T, respectively, in Japanese, and at 5.1%, 45.9%, 3.6%, 46.4% and 56.6%, respectively, in Caucasians, with a statistically significant difference for C1236T, G2677A,T and C3435T (p<0.001). G2677A was about 5-fold more frequent in Japanese than Caucasians. These genotype frequencies were also investigated in 95 Japanese patients with colorectal cancer (CRC) and esophageal squamous cell carcinoma (ESCC), but no significant difference was detected, when compared with healthy Japanese subjects. The haplotype frequency reached a total of about 85% in Japanese with the following 4 major haplotypes; T(-129)-T1236-T2677-T3435 (36.1%), T(-129)-T1236-G2677-C3435 (22.5%), T(-129)-C1236-G2677-C3435 (14.2%) and T(-129)-C1236-A2677-C3435 (13.3%). The second and fourth haplotypes were hardly inferred in Caucasian, whereas T(-129)-C1236-G2677-T3435 (12.8%) was found to be Caucasian-specific. There was a tendency for higher frequencies of the T(-129)/C-(129)-C1236-A2677-C3435 haplotype in Japanese CRC patients and T(-129)-T1236-T2677-T3435 haplotype in Japanese ESCC patients, compared with that in healthy Japanese subjects.     

Effects of ABCB1 (multidrug resistance transporter) gene mutations on disposition and central nervous effects of loperamide in healthy volunteers

OBJECTIVE: Mutations in the ABCB1 gene have been associated with decreased expression and net function of P-glycoprotein (P-gp). We investigated the modulation of the central nervous effects of loperamide resulting from ABCB1 genetic variants. METHODS: On two occasions, 20 healthy volunteers received 24 mg loperamide suspension orally and, in a double-blind randomized two-way crossover fashion, 800 mg quinidine or placebo orally 1 h before loperamide. Pupil size was measured for 5 h following loperamide administration, and plasma concentrations of loperamide and quinidine were measured for 6 h. Single nucleotide polymorphisms and haplotypes including G2677T(A) (exon 21) and C3435T (exon 26) were analysed for their relation to plasma concentrations of quinidine and loperamide and to the miotic effects of loperamide. RESULTS: Loperamide plasma concentrations with quinidine co-administration were about twice as high as those without quinidine. The ABCB1 haplotype G2677/T3435 was associated with the highest loperamide plasma concentrations, which were about 1.5 times higher than in non-carriers of this haplotype. Plasma concentrations of quinidine did not differ among carriers and non-carriers of genetic variants. When quinidine was co-administered with loperamide, pupil size decreased. Without quinidine it changed only minimally. The ABCB1 TT3435 genotype was associated with the most pronounced increase of the miotic effects of loperamide when quinidine was co-administered. This was accompanied by a tendency toward higher plasma loperamide in TT3435 carriers. CONCLUSIONS: Our data support a functional importance of the ABCB1 mutations for plasma concentrations and central nervous actions of the opioid loperamide.