荧光探针熔解曲线法检测结核患者N-乙酰基转移酶2基因型分布的应用评价

目的 评价荧光探针熔解曲线法检测结核病患者芳基胺N-乙酰基转移酶2(arylamine N-acetyltransferases 2,NAT2)基因多态性的性能。方法 选取于2015—2016年到福州肺科医院和北京胸科医院确诊的初治结核病患者作为研究对象,分别为371例和355例。收集研究对象外周血标本。应用荧光探针熔解曲线法[分析NAT2基因rs1801280(341T→G)、rs1799929(481C→T)、rs1799930(590G→A)和rs1799931(857G→A)等4个单核苷酸多态性(SNP)]和DNA测序分析法[分析NAT2基因的rs1801279 (191G→A)、rs1041983 (282C→T)、rs1801280(341T→C)、rs1799929 (481C→T)、rs1799930 (590G→A)、rs1208 (803A→G)和1799931 (857G→A)的7个SNP位点]对研究对象进行NAT2基因型分析,并根据NAT2基因型进行NAT2代谢类型的推断分析。结果 荧光探针熔解曲线法分析4个SNP位点与DNA测序分析法分析7个SNP位点推断NAT2代谢类型的结果完全一致。荧光探针熔解曲线法从DNA制备、PCR扩增和熔解曲线分析的整个检测过程需要2.5h。共检测到NAT2 *4/*4、NAT2 *5/*4、NAT2 *6/*4、NAT2 *7/*4、NAT2 *5/*11、NAT2 *6/*11、NAT2 *7/*11、NAT2 *5/*6、NAT2 *6/*7、NAT2 *5/*5、NAT2 *6/*6、NAT2 *7/*7、NAT2 *5/*7等13种NAT2基因型。福州肺科医院的结核病患者NAT2基因快乙酰化、中间乙酰化和慢乙酰化类型分别占37.20%(138/371)、42.32%(157/371)和20.49%(76/371);北京胸科医院的结核病患者中,快乙酰化、中间乙酰化和慢乙酰化类型分别占27.89%(99/355)、54.65%(194/355)、17.46%(62/355);两组人群的乙酰化类型分布差异有统计学意义(χ ²=11.37,P=0.003)。所有的快乙酰化代谢人群均携带NAT2 *4/*4基因型[100.00%(237/237)],而慢乙酰化代谢人群主要携带NAT2 *6和NAT2 *7的单倍型[90.22% (249/276)]。 结论 荧光探针熔解曲线法分析4个SNP位点检测NAT2基因型具有结果判读简便、准确、快速的优点,适用于中国地区人群的NAT2基因型的检测。     

310例中国人基因组干扰素α1/α2基因多态性研究

目的 若药品α-干扰素亚型与人体体内基因型不一致,接受抗病毒治疗的患者可被诱导产生更多的抗干扰素中和抗体,导致不应答和治疗失败。通过分析中国人群干扰素α1(IFNA1)和α2(IFNA2)基因多态性,可帮助阐明重组人干扰素α1和α2在中国人群中的遗传背景,为临床用药提供参考。方法 在单核苷酸多态性数据库中分别检索IFNA1基因和IFNA2基因编码区错义突变单核苷酸多态性(SNP)位点,再在千人基因组数据库查询收录的中国人IFNA1和IFNA2等位基因的分布情况,分析两种基因多态性并计算出相关的等位基因频率。结果 在千人基因组数据库共收录310例中国人双倍染色体基因组序列,所有中国人均有IFNA1和IFNA2基因座,其中,IFNA1基因座含有IFNα1、IFNα1(Ala137Val)和IFNα1(Arg148Gln) 三种等位基因,基因频率分别为99.6%、0.2%和0.2%;IFNA2基因座也含有IFNα2b、IFNα2b(Leu140Val)和IFNα2b(Ala120Thr)三种等位基因,基因频率分别为98.4%、0.2%和1.4%。结论 IFNα1和IFNα2b分别是中国人群IFNA1和IFNA2基因座的优势等位基因,在我国批准上市的IFNα1b、IFNα2a和IFNα2b三种亚型α-干扰素中,仅有IFNα2b与中国人基因型一致。     

代谢酶NAT2基因多态性与肺癌易感性关系的研究

目的 探讨代谢酶N-乙酰化转移酶2(NAT2)基因多态性与肺癌易感性的关系.方法 采用聚合酶链式反应-限制性片段长度多态性技术检测152名正常人和150例原发性肺癌患者的外周血NAT2基因型.应用病例对照研究分析NAT2基因多态性与肺癌易感性的关系.结果 ①NAT2等位基因型WT/WT、WT/Mx、Mx/Mx在对照组中分布频率分别为28.9%、52.0%和19.1%;在肺癌组中分布频率分别为22.0%、45.3%和32.7%,两组比较差异有统计学意义(P=0.023).②携带NAT2慢乙酰化基因型个体患肺癌的风险是携带NAT2快乙酰化基因型个体的1.84倍(95%CI为1.044～3.231,P=0.035).③携带慢乙酰化基因型个体患肺腺癌的风险进一步升高,是携带快乙酰化基因型个体的2.49倍(95%CJ为1.242～4.973,P=0.010).④携带NAT2慢乙酰化基因型吸烟者患肺癌的风险是携带快乙酰化基因型吸烟者的2.34倍(95%CI为1.007～5.424,P=0.048).结论 NAT2慢乙酰化基因型显著增加中国汉族人群尤其是吸烟者患肺癌的风险.     

荧光PCR探针熔解曲线技术检测涂阳患者痰标本中结核分枝杆菌耐药性的价值

目的 评估荧光PCR探针熔解曲线(MeltPro)技术检测涂阳患者痰标本中MTB耐药性的效能。方法 收集2016年9月至2018年8月西安市胸科医院500例痰涂片阳性患者的痰标本,分别进行痰涂片镜检、GeneXpert MTB /RIF检测、BACTEC MGIT 960(简称“MGIT 960”)液体培养、表型药物敏感性试验(简称“药敏试验”),并应用MeltPro法检测痰标本中MTB菌株对利福平、异烟肼、二线注射类和氟喹诺酮类等抗结核药物的耐药性,并以表型药敏试验为标准,评价MeltPro法的检测效能。结果 以表型药敏试验结果为标准,MeltPro法检测MTB对利福平耐药性的敏感度和特异度分别为98.7%(76/77)和94.2%(343/364),检测对异烟肼耐药性的敏感度和特异度分别为82.3%(102/124)和96.2%(304/316),检测对阿米卡星耐药性的敏感度和特异度分别为8/9和99.5%(432/434),检测对卷曲霉素耐药性的敏感度和特异度分别为6/7和99.1%(432/436),检测对左氧氟沙星耐药性的敏感度和特异度分别为90.6%(48/53)和99.2%(386/389),检测对莫西沙星耐药性的敏感度和特异度分别为88.1%(37/42)和96.5%(386/400)。以表型药敏试验结果为标准,GeneXpert MTB/RIF检测MTB对利福平耐药性的敏感度和特异度分别为94.8%(73/77)和94.0%(342/364)。GeneXpert-MTB/RIF和MeltPro法与表型药敏试验结果一致性均较好(Kappa值分别为0.81和0.84),但MeltPro法检测效能与表型药敏试验检测结果的一致性更高。结论 MeltPro法检测涂阳患者痰标本中MTB菌株对利福平、异烟肼,以及二线注射类和氟喹诺酮类抗结核药物耐药性有较好的效能。     

原发性胆汁性肝硬化患者外周血丝氨酸蛋白酶抑制剂A1基因多态性分析*

目的 探讨原发性胆汁性肝硬化(PBC)患者外周血丝氨酸蛋白酶抑制剂A1(SERPINA1)基因多态性变化。方法 2018年3月～2020年3月我院收治的PBC患者62例和同期健康体检者60例,采用基因测序法检测外周血SERPINA1基因rs28929474位点基因型,采用x²检验和哈迪-温伯格平衡检验SERPINA1 基因rs28929474位点基因型和等位基因分布差异。结果 两组人群SERPINA1 基因rs28929474位点基因型分布符合哈迪-温伯格平衡(P>0.05),具有群体代表性;PBC患者AA基因型和A等位基因频率分别为37.1%和46.8%,显著高于对照组的11.7 %和27.5 %(P>0.05),而GG、GA基因型和G等位基因频率分别为43.5%、19.4%和53.2%,显著低于对照组的56.7%、 31.7%和72.5%(P>0.05),提示A等位基因是罹患PBC的保护性因素,而G等位基因可能是患者发生PBC的风险因素;携带GA/AA型PBC患者Child评分和MELD评分分别为(7.9±1.8)分和(19.2±2.4)分,显著高于GG型PBC患者(P>0.05),而两组血清抗核抗体和抗线粒体抗体阳性率比较无显著性差异(P>0.05)。结论 本地区居民发生PBC可能与SERPINA1 基因rs28929474位点多态性有关,其中A基因可能是保护基因,而G基因可能是罹患疾病的风险基因。监测外周血SERPINA1 基因rs28929474位点多态性对于预测PBC发生具有一定的临床意义,值得探讨。     

2015-2016年无锡地区儿童肺炎支原体流行基因特征分析

目的 探讨无锡地区儿童肺炎支原体(MP)流行基因型特征及临床特点。方法 采用Real-time PCR法对无锡地区呼吸道感染患儿咽拭子标本进行检测;阳性标本进行P1基因分型、MLVA基因分型和大环内酯类相关耐药基因检测,并结合临床资料综合分析。结果 2015—2016年,无锡地区MP-DNA阳性率为8.68%(98/1 129),其中2015年、2016年MP阳性率分别为8.07%(44/545)和9.25%(54/584)。P1-RELP基因分型显示无锡地区P1-1型73.5%(25/34),P1-2型26.5%(9/34);MLVA分型显示无锡地区主要的基因型是M4-5-7-2(33/44)和M3-5-6-2(8/44),23S rRNA耐药基因检测显示大环内酯类耐药基因突变率为65.9%(29/44)。结论 2015—2016年无锡地区肺炎支原体感染率呈升高趋势,其中肺炎支原体P1-2型有增长趋势,提示该地区MP感染可能出现 P1-1型向P1-2型的型别转换,进而出现新的流行亚型。MLVA基因分型与肺炎支原体感染患儿临床表现之间暂未发现相关性。大环内酯类相关耐药基因的突变与患儿临床指标间暂未发现联系。     

重庆地区耐多药结核分枝杆菌三种二线注射类药物耐药相关基因特征分析

目的 分析重庆市耐多药结核病(MDR-TB)临床菌株二线注射类药物耐药相关基因突变特征,为本地区合理应用分子生物学技术进行注射类药物耐药性检测提供科学依据。方法 收集2015年1月至2017年6月重庆市39个区(县)967例MDR-TB可疑患者的所有耐多药(MDR)结核分枝杆菌临床分离株229株,通过微孔板Alamar blue显色法检测3种二线注射类药物[卡那霉素(Km)、阿米卡星(Am)、卷曲霉素(Cm)]的耐药性,用PCR测序方法对其耐药相关基因rrs、eis启动子区、tlyA进行分析,并采用荧光定量熔解曲线方法进行北京基因型鉴定。结果 在229株MDR菌株中,35株(15.3%,35/229)对三种二线注射类药物任一耐药,Km、Am和Cm耐药率分别为14.8%(34/229)、11.8%(27/229)、8.3%(19/229)。在34株Km耐药株中,21株发生rrs基因A1401G突变,1株rrs基因G1484T突变,4株eis启动子区G(-10)A突变及1株C(-14)T突变。在27株Am耐药株中,20株发生rrs基因A1401G突变,1株rrs基因G1484T突变,1株eis启动子区G(-10)A突变。在19株Cm耐药株中,13株发生rrs基因A1401G突变,1株rrs基因G1484T突变,1株tlyA基因137位碱基插入改变。北京与非北京基因型间注射类药物耐药及相关基因突变情况差异均无统计学意义。结论 重庆地区MDR结核分枝杆菌Km、Am和Cm各耐药相关基因呈现不同的突变频率特征,其中rrs基因突变频率最高,可作为三种注射类药物的耐药诊断标记物。北京基因型与二线注射类药物耐药无相关性。     

中国慢性HBV感染者基因型分布及其临床意义Meta分析*

目的 探讨中国乙型肝炎病毒（HBV）基因型分布及其临床意义。方法 在万方数据库和NCBI数据库检索有关中国HBV基因型分布的研究论文,将中国分为不同HBV感染流行区,分析不同地区、民族和肝脏疾病类型人群HBV基因A、B、C、B/C、D型和其他基因型（非A~D基因型和非B/C混合型）分布。采用Meta分析基因型分布特点及其临床意义。结果 在我国,HBV基因型主要以B基因型和C基因型为主,区域1（北部地区）HBV 基因A、B、C、B/C、D型和其他型分别为0.1%、22.2%、69.1%、3.8%、0.5%和1.5%,其中C基因型比例显著高于其它区域（P<0.05）;区域2（中部地区）HBV 基因A、B、C、B/C、D型和其他型分别为0.2%、62.6%、27.4%、3.8%、0.5%和2.4%,其中B基因型比例显著高于其它区域（P<0.05）;区域3（南部地区）HBV 基因A、B、C、B/C、D型和其他型分别为0.6%、36.3%、49.4%、2.8%、2.6%和3.4%,其中C基因型比例显著高于区域2的27.4%（P<0.05）;区域4（青藏高原）感染HBV B基因型、C基因型、D基因型和其他基因型分别为6.0%、22.5%、11.7%和59.3%,其中C/D混合型比例显著高于其他区域（P<0.05）;藏族人群C/D混合型比例（49.3%）显著高于其他民族（P<0.05）,哈萨克族D基因型比例（58.1%）显著高于其他民族（P<0.05）; C基因型与慢性乙型肝炎、HBV相关性肝硬化和肝癌显著相关（OR=1.979、OR=3.888、OR=4.399,P<0.001）。结论 不同地区和民族HBV基因型分布显著不同,B基因型可能是中国HBV起源基因,而感染C基因型更有可能引起严重的肝脏疾病。     

原发性胆汁性胆管炎患者血浆细胞毒性T淋巴细胞相关蛋白4基因多态性分析

目的 探讨原发性胆汁性胆管炎(PBC)患者血浆细胞毒性T淋巴细胞相关蛋白4(CTLA-4)基因多态性变化。方法 2015年9月～2020年12月我院诊治的PBC患者30例和同期健康体检者35例,采用聚合酶链反应-限制性片段长度多态性检测血浆CTLA－4基因rs231775、 rs4675369和rs7599230位点多态性。Logistic回归分析疾病风险关联。结果 PBC患者CTLA－4基因rs7599230位点基因型为CC型、CT型和TT型比率分别为16.7%、46.7%和36.6%,与健康人的20.0%、45.7%和34.3%比,无显著性差异(P＞0.05),等位基因C和T比率分别为40.0%和60.0%,与健康人群的42.9%和57.1%比,也无显著性差异(P＞0.05);PBC患者CTLA－4基因rs231775位点基因型为GG型和等位基因G比率分别为40.0%和61.7%,显著高于健康人的14.2%和35.7%(P＜0.05),AA基因型和等位基因A比率分别为16.7%和38.3%,显著低于健康人的42.9%和64.3%(P＜0.05);PBC患者CTLA－4基因rs4675369位点基因型为GG型和等位基因G比率分别为43.3%和65.0%,显著高于健康人的17.1%和41.4%(P＜0.05),AA基因型和等位基因A比率分别为13.4%和35.0%,显著低于健康人的34.3%和58.6%(P＜0.05);经非条件Logistic回归模型计算,校正性别和年龄,结果显示rs4675369位点GG基因型是影响PBC发生的危险基因型,其OR值为1.523((95%CI:1.113～2.085),rs231775位点GG基因型也是影响PBC发生的危险基因型,其OR值为1.636((95%CI:1.161～2.305) 。结论 CTLA-4基因rs231775和rs4675369位点GG基因型可能是PBC发生的易感基因型,值得进一步研究。     

中国HCV基因型分布的Meta分析*

目的 分析中国不同地区、民族和感染途径人群丙型肝炎病毒(HCV)基因型的分布特点。方法 通过检索万方数据库和NCBI数据库中有关中国HCV基因型分布的文献,按照地区、民族和感染途径进行数据分类,应用Meta分析研究HCV基因型的分布特点。结果 在我国,HCV1型流行最广泛,北部地区主要为1型(52.7%～79.7%)和2型(13.9%～44.9%),东南部地区主要为1型(51.7%～79%),6型在香港(31.3%)、广东(23.1%)、福建(21.8%)、澳门(20.6%)地区分布较多,西南部地区主要为1型(19.7%～73.4%)和3型(13.4%～58.5%),西部地区主要为1型(53.6%～66.8%),也有较多的2型(15.8%～32.1%)和3型(12.8%～15.8%);朝鲜族2型比例(42.2%)显著高于汉族(22.4%,P<0.001)、维吾尔族(13.1%,P<0.001)和哈萨克族(18.5,P=0.004),维吾尔族3型比例(16.6%)显著高于汉族(9.4%,P<0.001);静脉吸毒人群感染HCV 3型比例(31.1%)显著高于血液感染相关人群(4.5%,P<0.001)、性传播感染人群(24.1%,P=0.003),静脉吸毒人群感染HCV6型比例(26.7%)显著高于血液感染相关人群(4.1%,P<0.001)和性传播感染人群(15.1%,P<0.001);在HCV/HIV混合感染者中3型和6型比例显著高于单纯HCV感染者(P<0.001)。结论 在不同地区、民族和感染途径人群中HCV基因型分布存在显著性差异,了解这些差异并进行针对性的处理可能有助于防治研究。     

N-acetyltransferase 2 slow acetylator genotype associated with adverse effects of sulphasalazine in the treatment of inflammatory bowel disease.

AIM: N-acetyltransferase 2 (NAT2) is an important enzyme catalyzing N-acetylation of sulfasalazine (SASP). The aim of the present study was to investigate associations of the genotypes of NAT2 with inflammatory bowel disease (IBD), and with adverse effects of SASP, which is used as the first-line treatment of IBD. PATIENTS AND METHODS: The wildtype allele (NAT2*4) and three variant alleles (NAT2*5B, NAT2*6A and NAT*7B) of the NAT2 gene were determined in 101 patients with IBD (84 patients with ulcerative colitis and 17 patients with Crohn's disease) and 109 healthy controls by the polymerase chain reaction-restriction fragment length polymorphism method. Sixty-eight patients with IBD treated with SASP were followed, and their adverse reactions were recorded. RESULTS: Eleven patients (16%) experienced adverse effects from SASP, including nine cases of sulfapyridine (SP) dose-related adverse effects and two cases of hypersensitivity (skin rash). Patients with the slow acetylator genotypes without the NAT2*4 allele experienced adverse effects more frequently (36%) than those with the fast acetylator genotypes with at least one NAT2*4 allele (11%), but the results were not significantly different (OR of 0.26, 95% CI 0.065 to 1.004; P=0.051). However, those with the slow acetylator genotypes experienced more SP dose-related adverse effects than those with the fast acetylator genotypes (36% versus 8%, OR of 0.17, 95% CI 0.039 to 0.749; P=0.019). CONCLUSIONS: The NAT2 gene polymorphism was not associated with susceptibility to IBD in Chinese populations, but the NAT2 slow acetylator genotypes were significantly associated with SP dose-related adverse effects of SASP in the treatment of IBD.     

N-acetyltransferase 2 polymorphism is not related to the risk of advanced alcoholic liver disease

BACKGROUND: Ethanol abuse is the most prevalent cause of liver cirrhosis in Spain. Genetic polymorphisms affect the activity of the enzymes involved in ethanol metabolism and in processing the toxic by-products generated in the liver. N-acetyltransferase 2 (NAT2) is a polymorphic phase 2 enzyme not involved in these processes, but recent data suggest that the most prevalent slow acetylator genotype protects against the risk of advanced alcoholic liver disease (ALD). We have identified six single nucleotide polymorphisms (SNP) at the NAT2 gene locus in order to disclose whether such an association exists. METHODS: Genomic DNA from 95 ALD patients (15 with superimposed hepatocellular carcinoma (HCC)) and from 258 healthy individuals was analysed for SNPs at the coding region of the NAT2 gene by means of allele-specific polymerase chain reaction. RESULTS: There are no differences in the relative frequencies of the eight identified NAT2 alleles (including the wild-type allele) nor in the distribution of predicted phenotypes (54% of slow acetylators in each group). Twelve patients with HCC (80%) were slow acetylators (P < 0.05). CONCLUSIONS: There is no relationship between the NAT2 genotype and the risk of ALD. Slow acetylator genotype may predispose to the development of HCC in severe ALD patients not infected by the hepatitis C virus.     

N-acetyltransferase 1 and 2 genotypes do not predict response or toxicity to treatment with mesalamine and sulfasalazine in patients with ulcerative colitis

OBJECTIVES: 5-Aminosalicylate is metabolized in colonic mucosa by N-acetyltransferase 1 (NAT1), and sulfapyridine is metabolized in the liver by N-acetyltransferase 2 (NAT2). Common genetic polymorphisms in these enzymes result in rapid and slow acetylation. We determined the association between NAT1 genotype and response to mesalamine and sulfasalazine, as well as between NAT2 genotype and toxicity to sulfasalazine, in a population-based cohort of patients with ulcerative colitis. METHODS: DNA was obtained from 77 white patients with ulcerative colitis from Olmsted County, MN. NAT1 and NAT2 genotyping was performed using microelectronic array devices. Phenotypes were deduced from previously published genotype/phenotype correlations. Clinical response to mesalamine and sulfasalazine, and toxicity to sulfasalazine, were determined by medical record review and associated with NAT1 and NAT2 genotypes. RESULTS: The clinical response rates among 52 patients treated with mesalamine were 67% (31 of 46) for rapid acetylators and 83% (five of six) for slow acetylators (odds ratio = 0.4, 95% CI = < 0.1-3.9, p = 0.65). Similarly, the clinical response rates among 64 patients treated with sulfasalazine were 74% (43 of 58) for rapid acetylators and 67% (four of six) for slow acetylators (odds ratio = 1.4, 95% CI = 0.2-8.6, p = 0.65). The toxicity rates among the 64 patients treated with sulfasalazine were 34% (12 of 35) for slow acetylators and 45% (13 of 29) for rapid acetylators (odds ratio = 0.6, 95% CI = 0.2-1.8, p = 0.65). CONCLUSIONS: NAT1 and NAT2 genotypes did not predict response to mesalamine or sulfasalazine, or toxicity to sulfasalazine.     

N -Acetyltransferase 2 Polymorphism Is Not Related to the Risk of Advanced Alcoholic Liver Disease

Background: Ethanol abuse is the most prevalent cause of liver cirrhosis in Spain. Genetic polymorphisms affect the activity of the enzymes involved in ethanol metabolism and in processing the toxic by-products generated in the liver. N -acetyltransferase 2 (NAT2) is a polymorphic phase 2 enzyme not involved in these processes, but recent data suggest that the most prevalent slow acetylator genotype protects against the risk of advanced alcoholic liver disease (ALD). We have identified six single nucleotide polymorphisms (SNP) at the NAT2 gene locus in order to disclose whether such an association exists. Methods: Genomic DNA from 95 ALD patients (15 with superimposed hepatocellular carcinoma (HCC)) and from 258 healthy individuals was analysed for SNPs at the coding region of the NAT2 gene by means of allele-specific polymerase chain reaction. Results: There are no differences in the relative frequencies of the eight identified NAT2 alleles (including the wild-type allele) nor in the distribution of predicted phenotypes (54% of slow acetylators in each group). Twelve patients with HCC (80%) were slow acetylators ( P < 0.05). Conclusions: There is no relationship between the NAT2 genotype and the risk of ALD. Slow acetylator genotype may predispose to the development of HCC in severe ALD patients not infected by the hepatitis C virus.     

Thiopurine metabolites variations during co-treatment with aminosalicylates for inflammatory bowel disease:Effect of N-acetyl transferase polymorphisms

AIM: To evaluate variation of the concentration of thiopurine metabolites after 5-aminosalicylate(5-ASA) interruption and the role of genetic polymorphisms of N-acetyl transferase(NAT) 1 and 2. METHODS: Concentrations of thioguanine nucleotides(TGN) and methymercaptopurine nucleotides(MMPN), metabolites of thiopurines, were measured by high performance liquid chromatography in 12 young patients(3 females and 9 males, median age 16 years) with inflammatory bowel disease(6 Crohn’s disease and 6 ulcerative colitis) treated with thiopurines(7 mercaptopurine and 5 azathioprine) and 5-ASA. Blood samples were collected one month before and one month after the interruption of 5-ASA. DNA was extracted and genotyping of NAT1, NAT2, inosine triphosphate pyrophosphatase(ITPA) and thiopurine methyl transferase(TPMT) genes was performed using PCR assays. RESULTS: Median TGN concentration before 5-ASA interruption was 270 pmol/8 x 108 erythrocytes(range: 145-750); after the interruption of the aminosalicylate, a 35% reduction in TGN mean concentrations(absolutemean reduction 109 pmol/8 × 108 erythrocytes) was observed(median 221 pmol/8 × 108 erythrocytes, range: 96-427, P value linear mixed effects model 0.0011). Demographic and clinical covariates were not related to thiopurine metabolites concentrations. All patients were wild-type for the most relevant ITPA and TPMT variants. For NAT1 genotyping, 7 subjects presented an allele combination corresponding to fast enzymatic activity and 5 to slow activity. NAT1 genotypes corresponding to fast enzymatic activity were associated with reduced TGN concentration(P value linear mixed effects model 0.033), putatively because of increased 5-ASA inactivation and consequent reduced inhibition of thiopurine metabolism. The effect of NAT1 status on TGN seems to be persistent even after one month since the interruption of the aminosalicylate. No effect of NAT1 genotypes was shown on MMPN concentrations. NAT2 genotyping revealed that 6 patients presented a genotype corresponding to fast enzymatic activity and 6 to slow activity; NAT2 genotypes were not related to thiopurine metabolites concentration in this study. CONCLUSION: NAT1 genotype affects TGN levels in patients treated with thiopurines and aminosalicylates and could therefore influence the toxicity and efficacy of these drugs; however the number of patients evaluated is limited and this has to be considered a pilot study.     

Cytochrome P450 (CYP) 1A2, sulfotransferase (SULT) 1A1, and N-acetyltransferase (NAT) 2 polymorphisms and susceptibility to urothelial cancer

Purpose Arylamines are suspected to be the primary causative agent of urothelial cancer in tobacco smoke. In the human liver, arylamines are N-hydroxylated by a cytochrome P450 (CYP)1A2-catalyzed reaction, which produces a substrate for O-esterification that can be catalyzed by N-acetyltransferases (NAT) or sulfotransferases (SULT). Recently, several polymorphisms of CYP1A2, SULT1A1, and NAT2 that affect their activities have been reported.Methods In this study, 306 Japanese patients with urothelial transitional cell carcinoma and 306 healthy controls were compared for frequencies of CYP1A2, SULT1A1, and NAT2 genotypes.Results The frequencies of NAT2 intermediate or slow acetylator genotype were significantly higher in the urothelial cancer patients than in the healthy control subjects [odds ratio (OR)=1.49, 95% confidence interval (95% CI) 1.06–2.09, OR=3.23, 95% CI 1.72–6.08, respectively]. Stratifying by amount of smoking, among subjects who consumed >33.5 pack-years and carried the SULT1A1 *1/*1 or NAT2 slow acetylator genotype, the OR was 1.73 (95% CI 1.01–2.97) whereas it was 7.31 (95% CI 1.90–28.05) in non-smokers who carried the homozygous wild genotype, respectively. The relationships between CYP1A2, SULT1A1, and NAT2 polymorphisms and clinical findings including tumor differentiation, stage, and recurrence rate were analyzed. Only associations between NAT2 genotype and pathological findings were admitted, and the higher OR of NAT2 intermediate and slow acetylator genotype was more likely to present to a low-grade tumor (G1) among heavy-smokers.Conclusions Our results suggest that SULT1A1 *1/*1 and NAT2 slow acetylator genotypes might modulate the effect of carcinogenic arylamines contained in tobacco smoke, and that the modulation of NAT2 intermediate and slow acetylator genotype has a tendency to present a higher risk for highly differentiated tumors among heavy-smokers.     

PCI术后患者的CYP2C19基因型分布及其基因型指导抗血小板治疗的效果

目的:描述中国西北地区汉族人群经皮冠状动脉介入(PCI)术后患者细胞色素P450(CYP2C19)基因多态性分布特点,并评价依据基因型指导PCI术后氯吡格雷抗血小板治疗的效果。方法:1入选2013年1月7月在西京医院心内科行PCI的来自西北地区汉族患者2 117例行CYP2C19基因型检测,根据不同等位基因功能缺失分为快代谢基因型(*1/*1)、中间代谢基因型(*1/*2、*1/*3)和慢代谢基因型(*2/*2、*2/*3、*3/*3);2从上述人群中选择临床资料完整的患者153例,按基因型分为2组:正常代谢组(快代谢基因型,59例)和弱代谢组(中间代谢和慢代谢基因型,94例)。正常代谢组患者术后口服氯吡格雷75 mg/d至1年,而弱代谢组氯吡格雷150 mg/d强化治疗1个月,后75 mg/d至1年抗血小板治疗;于术后1、3、6、9和12个月随访并记录和比较两组间主要不良心脑血管事件(MACE)发生情况。结果:1检测入选的2117例患者基因型结果显示,快代谢基因型(*1/*1)885例,发生率41.80%,中间代谢基因型(*1/*2、*1/*3)971例,发生率45.86%,其中*1/*2占39.16%,*1/*3占6.70%,慢代谢基因型(*2/*2、*2/*3、*3/*3)261例,发生率12.32%。2正常代谢组失訪6例,弱代谢组失訪5例,两组失訪率(9%vs.5%)差异未达到显著水平。正常代谢组和弱代谢组MACE发生率[12.3%(6/59)vs.10.1%(8/94),两组差异也无统计学意义。结论:1入选患者CYP2C19等位基因突变频率发生率高,其中以*1/*2为主,2按基因型采取不同剂量的抗血小板药物后两组MACE发生率差异无统计学意义。     

CYP2E1和NAT2基因多态性与抗结核药物诱导的药物性肝损伤关系的荟萃分析

目的明确细胞色素氧化酶P450 2E1(cytochrome P450 2E1,CYP2E1)和N-乙酰基转移酶-2(N-acetyltransferase-2,NAT2)基因多态性与抗结核药诱导的药物性肝损伤(anti-tuberculosis drug-induced hepatotoxicity,ATDH)之间的关系。方法计算机检索Medline/Pubmed、EMBASE、Web of Science数据库和Cochrane图书馆中所有有关CYP2E1基因多态性与ATDH关系的研究文献。根据文献纳入及排除标准筛选文献,并对文献进行质量评价。采用OR及95%CI作为分析疗效的统计量。采用Revman 5.0软件统计分析。结果共计纳入研究文献9篇,入选2049例研究对象。CYP2E1基因Pst I/Rsa I多态性中,c1/c1型比c1/c2和c2/c2型有更高的ATDH发生率(OR=1.38,95%CI:1.08~1.77,P=0.01);在Dra I多态性中各型之间无差异(OR=0.78,95%CI:0.51~1.18,P=0.23)。与携带NAT2快速或中速乙酰化的c1/c1型人群比较,携带NAT2慢速乙酰化的c1/c1型人群具有更高的ATDH风险(OR=3.10,P0.0001)。结论 CYP2E1基因c1/c1型是ATDH发生的风险因素,且合并慢速乙酰化的NAT2基因型时可进一步增加ATDH发生率。