尿苷二磷酸葡萄糖醛酸转移酶1A1*28基因多态性和伊立替康毒副反应相关性研究

目的初步了解肿瘤患者血中尿苷二磷酸葡萄糖醛酸转移酶1A1(UGT1A1)启动子的多态性分布,并研究其多态性和伊立替康化疗的毒副反应之间的关系。方法收集拟采用伊立替康为基础化疗方案的患者全血标本,直接测序分析UGT1A1~*28 TATA盒基因序列;并与化疗毒副反应进行相关性分析。结果 203例患者进行UGT1A1~*28 TATA基因启动子检测,UGT1A1~*28野生纯合型(TA6/6)最常见,共156例,占76.8%;其次为突变杂合型(TA6/7),共43例,占21.2%;突变纯合型(TA7/7)仅3例,占1.5%;TA5/6有1例,占0.5%。共有183例患者使用含伊立体康方案治疗。突变纯合型(TA7/7)与3度及以上迟发型腹泻和中性粒细胞减少明确相关(P=0.001、P=0.048),与化疗前总胆红素水平升高相关(P0.001);突变杂合型(TA6/7)和野生纯合型(TA6/6)在3度及以上迟发型腹泻和中性粒细胞减少方面的相关性类似(P=0.561、P=0.915),化疗前总胆红素水平类似(P=0.229)。结论 UGT1A1~*28突变纯合型(TA7/7)明显增加伊立替康所致3度及以上延迟性腹泻和中性粒细胞减少,增加化疗前胆红素水平;而UGT1A1~*28突变杂合型(TA6/7)并不增加3、4度迟发型腹泻和粒细胞减少的发生及化疗前总胆红素水平。     

尿苷二磷酸葡醛酰转移酶1A1基因多态性与伊立替康治疗广泛期小细胞肺癌不良反应的相关性

目的 研究尿苷二磷酸葡醛酰转移酶(UGT) 1A1基因多态性与伊立替康方案治疗广泛期小细胞肺癌患者不良反应的关系.方法 采用聚合酶链反应法扩增目的基因片段,直接测序法对UGT1 A1基因多态性进行检测,观察并记录化疗中出现的不良反应及疗效,比较不同基因型患者使用伊立替康不良反应的发生率.结果 58例广泛期小细胞肺癌患者中,UGT1A1* 28野生型45例(77.6％),UGT1 A1 *93野生型40例(69.0％),UGT1A1* 60野生型38例(65.5％),UGT1 A1* 93和UGT1 A1* 60基因突变分别有18例(31.0％)和20例(34.5％).UGT1A1* 28基因型中,TA5突变8例(13.8％),TA7突变5例(8.6％).TA5突变型中≥3级腹泻5例,≥3级白细胞和中性粒细胞减少各3例;UGT1 A1* 93突变型中,≥3级腹泻7例,≥3级白细胞减少6例,≥3级中性粒细胞减少4例.结论 TA5突变型、UGT1A1*93突变型均增加腹泻和≥3级白细胞和中性粒细胞减少的风险,而UGT1 A1(*28、*93、*60)野生型和UGT1 A1* 60突变型未增加药物不良反应的风险.     

UGT1A1*28基因多态性与晚期结直肠癌伊立替康化疗疗效及不良反应的关系

目的:尿苷二磷酸葡糖醛酸转移酶1A1(uridine-diphosphoglucuronosyl transferase 1A1, UGT1A1)作为伊立替康重要的药物代谢酶,其基因多态性可显著影响该酶的活性.本研究旨在观察UGT1A1*28基因多态性与晚期结直肠癌伊立替康化疗疗效和不良反应之间的关系.方法:回顾性研究64例接受伊立替康/氟尿嘧啶一线化疗的晚期结直肠癌患者.从患者外周血白细胞中提取DNA,应用直接测序法检测UGT1A1*28 TATA盒基因序列,并分析基因多态性与化疗不良反应和近期疗效的关系.结果: 51例(79.7%)患者的UGT1A1*28基因启动子区TA序列重复6次,为纯合野生型(TA)6/(TA)6;10例(15.6%)患者的基因型为TA序列重复6次和7次的杂合型(TA)6/(TA)7;3例(4.7%)患者的TA序列重复7次,为纯合突变型(TA)7/(TA)7.UGT1A1*28非野生型的基因多态性可增加患者发生Ⅲ度以上腹泻的风险(38.5% vs 9.8%,P=0.035);UGT1A1*28非野生型基因患者接受伊利替康化疗时,需要下调剂量的比率明显高于野生型基因者(46.2% vs 15.7%,P=0.046).64例患者中28例(43.8%)化疗有效,其中UGT1A1*28野生型基因者22例,非野生型基因者6例,2组的反应率差异无统计学意义(46.2% vs 43.1%,P=0.845).结论:在应用伊立替康化疗的患者中,UGT1A1*28基因启动子区TATA盒基因多态性(TA)6/(TA)7或(TA)7/(TA)7基因型可增加晚期结直肠癌患者接受伊立替康化疗后,发生Ⅲ度以上腹泻的风险,但不影响化疗的近期疗效.     

UGT1A1基因多态性与伊立替康安全性和有效性的临床研究

  目的  观察57例应用伊立替康治疗进展期消化道肿瘤患者的安全性和有效性。  方法  采用全血基因组DNA提取、PCR法扩增目的基因片段, 直接测序法分析UGT1A1基因多态性, 检测2011年8月至2012年6月在河北医科大学第四医院肿瘤内科住院治疗的57例进展期消化道肿瘤患者应用伊立替康的情况, 观察并记录化疗中出现的不良反应以及疗效。  结果  57例进展期消化道肿瘤患者中, UGT1A1基因启动子区28位点, TA序列6次重复的纯合野生型TA6/6有43例（75.4%）; 基因型为TA序列6次和7次重复的杂合型TA6/7有13例（22.8%）; 基因型为TA序列7次重复的纯合突变型TA7/7有1例（1.8%）。UGT1A1基因启动子区6位点野生型G/G有48例（84.2%）, 杂合突变型G/A有7例（12.3%）, 纯合突变型A/A有2例（3.5%）。在57例采用含伊立替康方案化疗的进展期消化道肿瘤患者中, UGT1A1基因启动子区28位点, TA6/6、TA6/7和TA7/7野生型和突变型发生3级以上中性粒细胞减少者分别为7.0%、14.3%, 发生3级以上腹泻者分别为9.3%、14.3%, 其中纯合突变型仅1例患者, 100%的发生率。UGT1A1基因启动子区6位点, G/G、G/A和A/A野生型和突变型发生3级以上中性粒细胞减少者分别为4.2%、55.6%, 发生3级以上腹泻者分别为12.5%、44.4%, 具有统计学差异。各组之间疗效无统计学差异。  结论  患者UGT1A1*28和UGT1A1*6多态性分布基本一致, UGT1A1*6突变型患者应用伊立替康化疗发生3级以上中性粒细胞减少和腹泻的风险增加, 而UGT1A1*28突变型与以上不良反应并无绝对相关性, UGT1A1各基因型之间疗效无明显差异。能否通过对UGT1A1的筛查, 选择合适患者安全有效的应用伊立替康, 值得临床进一步扩大样本量深入研究。      

UGT1A1基因多态性与伊立替康临床用药安全性及疗效的关系

目的：研究 UGT1A1基因多态性与伊立替康治疗结直肠癌患者的不良反应及疗效之间的关系。方法：自外周血中抽提基因组 DNA,进行 PCR 扩增,应用直接测序法分析2012年3月至2013年3月,于我院行基因检测的65例结直肠癌患者 UGT1A1*28和 UGT1A1*6基因多态性的分布情况。并对这65例应用含伊立替康方案化疗的患者出现的不良反应及化疗疗效,进行观察记录,比较不同基因型间的差异。结果：65例患者中,UGT1A1*28野生型 TA6／6有49例（75．4％）,杂合突变型 TA6／7有14例（21．5％）,纯合突变型TA7／7有2例（3．1％）。UGT1A1*6野生型 G／G 有47例（72．3％）,杂合突变型 G／A 有15例（23．1％）,纯合突变型 A ／A 有3例（4．6％）。在以上65例结直肠癌患者中,UGT1A1基因启动子区28位点,TA6／6、TA6／7和TA7／7型,发生3级以上腹泻者分别为8．2％、37．5％;发生3级以上中性粒细胞减少者分别为28．6％、62．5％。UGT1A1基因启动子区6位点,G／G、G／A 和 A ／A 型,发生3级以上腹泻者分别为12．8％、44．4％;发生3级以上中性粒细胞减少者分别为14．9％、22．2％。各组之间疗效无统计学差异。结论：患者 UGT1A1*28和UGT1A1*6多态性分布基本一致,UGT1A1*28突变型可以使应用含伊立替康化疗患者发生3级以上腹泻和中性粒细胞减少的风险增加。UGT1A1*6突变型可增加3级以上腹泻的发生风险。因此,UGT1A1基因型的检测对伊立替康相关的不良反应有一定的预测作用,可提高用药安全性,在临床用药中起到了指导作用。     

川东北地区人群结直肠癌患者UGT1A1*28基因多态性与伊立替康所致毒副反应的相关性

目的:观察结直肠癌患者UGT1A1*28基因多态性的分布频率,了解UGT1A1*28基因多态性与结直肠癌患者应用伊立替康联合5-氟尿嘧啶化疗毒副反应的相关性。方法:从384例接受伊立替康联合氟尿嘧啶一线化疗的晚期结直肠癌病例中采外周血提取DNA。采用PCR 法扩增目的基因片段,直接测序法分析UGT1A1*28基因多态性。临床观察并评价患者化疗毒副反应分级,统计分析UGT1A1*28基因表型与化疗毒副反应相关性。结果:全部 384例患者 UGT1A1*28基因多态性分布情况:TA6/6野生基因型287例(74.7％),TA6/7杂合基因型73例（19.0％）,TA7/7纯合基因型24例（6.3％）。化疗毒副反应和UGT1A1*28基因多态性进行临床单因素分析显示UGT1A1*28基因纯合型TA7/7、杂合型TA6/7与3-4度白细胞减少、中性粒细胞减少、腹泻、胆红素升高具有明显相关性（P<0.01）,UGT1A1*28基因纯合型TA7/7及杂合型TA6/7患者发生中性粒细胞减少的风险较UGT1A1*28基因野生型TA6/6患者高5.625倍（OR=5.625）。UGT1A1*28基因纯合型TA7/7和UGT1A1*28基因杂合型TA6/7患者发生腹泻的风险较UGT1A1*28基因野生型TA6/6患者高6.778倍（OR=6.778）。结论:UGT1A1*28基因纯合型TA7/7及杂合型TA6/7患者应用伊立替康化疗后发生重度中性粒细胞减少、重度腹泻的风险高于UGT1A1*28基因野生型TA6/6,为临床伊立替康用药选择、剂量调整、毒副反应的提前干预提供理论依据。     

UGT1A1基因多态性与伊立替康治疗结直肠癌不良反应的关系

背景与目的：尿苷二磷酸葡萄糖醛酸转移酶1A1(uridine diphosphoglucu-ronosyltransferase 1A1,UGTlA1)是伊立替康代谢关键酶,其活性受基因多态性影响显著。本研究探讨结直肠癌患者中,UGT1A1*28和UGT1A1*6基因多态性与伊立替康治疗相关不良反应之间的关系。方法：入组2013年4月—2013年12月于复旦大学附属中山医院肿瘤内科接受治疗的消化道恶性肿瘤患者160例。抽提外周血中基因组DNA,分别采用STR方法和Sanger测序法,检测UGT1A1*28和UGT1A1*6基因型,分析UGT1A1基因多态性分布情况。对其中82例化疗方案中含伊立替康的结直肠癌患者进行随访,记录不良反应发生情况和严重程度,比较不同基因型患者之间的差异。结果：160例消化道肿瘤患者中,UTG1A1*28(启动子TATA盒区域TA重复次数)野生型TA6/6124例(77.5%);杂合子TA6/7 33例(20.5%);纯合子TA7/7 3例(2.0%)。UGT1A1*6位点(211G>A)野生型GG 105例(65.6%),杂合子GA 48例(30.0%);纯合子AA 7例(4.4%)。82例化疗方案中含伊立替康的结直肠癌患者中,*28基因型(TA6/7和TA7/7)显著增加发生3级以上中性粒细胞减少的风险(58.3% vs 0.0%,P<0.001),并增加整体不良反应发生率(76.0% vs 45.6%,P<0.001);*6基因型(GA和AA)、年龄、性别、化疗方案和伊立替康相关不良反应发生无显著相关性。结论：接受伊立替康化疗的结直肠癌患者,UGT1A1*28位点多态性显著增加中性粒细胞减少发生的风险,可预测伊立替康引起的骨髓抑制性不良反应,辅助临床选择合适的化疗方案。     

UGT1A1*28/6基因多态性与广西壮族晚期结直肠癌伊立替康化疗的相关性研究

摘 要：［目的］探讨尿苷二膦酸葡萄糖醛酸转移酶1A1（uridine diphosphate-glucuronosy1transferase1A1,UGT1A1)基因多态性在壮族晚期结直肠癌(metastatic colorectal cancer,mCRC)患者以伊立替康(Irinotecan,CPT-11)为基础方案化疗的毒副反应及疗效关系。［方法］ 收集120例广西壮族mCRC患者外周血标本,采用聚合酶链式反应（polymerasechaainreaction,PCR)法扩增目的基因片段,检测UGT1A1*28/6基因型,评估以CPT-11为基础方案化疗的毒副反应及近期疗效。［结果］120例转移性结直肠癌中,UGT1A1*28野生型（TA6/6）81例,杂合型（TA6/7）37例,纯合型（TA7/7）2例;UGT1A1*6野生型（G/G）93例,杂合型（G/A）24例,纯合型（A/A）3例。UGT1A1*6基因突变（杂合型+纯合型）可增加3～4级中性粒细胞和3～4级迟发性腹泻风险的发生率（χ2=6.172,P=0.017;χ2=19.079,P<0.001）,UGT1A1*28基因突变（杂合型+纯合型）可增加3～4级迟发性腹泻发生的风险（χ2=8.274,P=0.004）。联合UGTlAl*28和UGTlAl*6基因,野生型患者3～4级中性粒细胞减少和迟发性腹泻的发生率明显低于单点突变型和双点突变型(χ2=6.860,P=0.032;χ2=10.277,P=0.006）。同时较之野生型,单点突变型和双点突变型患者化疗后中性粒细胞计数显著减少（P=0.008;P=0.001)。野生型与突变型患者的总缓解率（over response rate,ORR）和疾病控制率（disease control rate,DCR）差异均无统计学意义（P=0.739;P=0.789）。两种基因联合,野生型、单点突变型和双点突变型患者的ORR和DCR差异亦均无统计学意义（P=0.968,P=0.865)。［结论］ UGT1A1*28基因和UGT1A1*6基因双点突变型可增加壮族结直肠癌患者CPT-11严重骨髓抑制和重度延迟性腹泻发生的预测价值与效能,但UGT1A1*28/6基因多态性与近期疗效无关。     

UGT1A1*28基因多态性与中药预防伊立替康腹泻效果的关系

  目的  探讨中药对伊立替康化疗后腹泻的预防作用,同时结合尿苷二磷酸葡萄糖醛酸转移酶1A1*28（UGT1A1*28）基因多态性进行中药疗效分析。  方法  自2011年10月至2013年5月共200例患者被随机分为对照组（单纯化疗）和中药组（化疗联合中药）。全部患者在化疗开始前均接受UGT1A1*28基因多态性的检测。化疗采用标准FOLFIRI方案,中药于化疗前2 d开始服用,至伊立替康化疗后第5天结束。期间记录患者不良反应,并进行疗效评价。  结果  200例患者中TA6/6野生基因型144例,非野生基因型56例（TA7/7纯合型12例和TA6/7杂合型44例）。2级以上腹泻者共58例,中药组腹泻发生率较对照组下降14%（22% vs. 36%,P=0.029）。除腹泻以外,2级以上呕吐发生率中药组也明显低于对照组（15% vs. 27%,P=0.037）。患者总体有效率为37.5%,中药组和对照组相比差异无统计学意义（40% vs. 35%,P=0.465）。UGT1A1*28野生基因型患者2级以上腹泻发生率（22.9% vs. 44.6%,P=0.002）和呕吐发生率（16.7% vs. 23.2%,P=0.016）均低于与非野生基因型患者。在中药治疗组中,非野生基因型与野生型相比,2级以上腹泻发生率（22.2% vs. 21.9%,P=0.974）和呕吐发生率（18.5% vs. 13.7%,P=0.777）差异无统计学意义。  结论  中药可有效预防伊立替康引起的迟发性腹泻,对于UGT1A1*28非野生基因型患者的迟发性腹泻同样具有预防作用。UGT1A1*28基因非野生基因型腹泻发生率明显高于野生基因型,在使用伊立替康治疗前应检测患者的该基因状态。      

中国人尿苷二磷酸葡糖苷酸转移酶1A基因多态性与伊立替康毒性的相关性

目的评价伊立替康(CVT-11)联合5-氟尿嘧啶(5-Fu)和亚叶酸钙(LV)治疗晚期大肠癌的毒性与尿苷二磷酸葡糖苷酸转移酶1A(UGT1A)基因多态性的相关性。方法收集70例晚期大肠癌患者及健康志愿者的外周血,提取基因组DNA,PCR法扩增目的基因片段,直接测序法分析UGT1A基因多态性,并与毒性进行相关性分析。结果70例晚期大肠癌患者的3～4度中性粒细胞减少发生率为20.O%(14/70);2～4度迟发性腹泻发生率为22.9%(16/70),其中3-4度迟发性腹泻率仅为5.7%(4/70)。UGT1A1*28的野生基因型TA6/6患者的2-4度迟发性腹泻发生率为15.7%,低于TA6/7和TA7/7基因型的患者(P=0.027)。健康人群和大肠癌患者UGT1A基因家族中各个基因多态性的分布无差别。结论UGT1A1*28的野生基因型TA6/6在中国人中分布频率较高,这也是CPT-11为主方案治疗晚期大肠癌发生严重迟发性腹泻较少的原因。     

NAT1*10 and NAT1*11 polymorphisms and breast cancer risk.

Several recent epidemiological studies examined the association of N-acetyltransferase (NAT) 1 and 2 genotypes and breast cancer risk. Taken together, these studies do not support a strong role for the most common NAT alleles in etiology of breast cancer. Only one study estimated odds ratios (ORs) for the relatively rare NAT1*11 allele: a strong positive association for the NAT1*11 allele and breast cancer was reported, as well as strong combined effects for NAT1*11-containing genotypes and two environmental factors, smoking and red meat consumption. To further address the association of NAT1*11 and breast cancer, an analysis was performed using previously collected data from the Carolina Breast Cancer Study, a population-based, case-control study conducted in North Carolina. The OR for NAT1*11-containing genotypes and breast cancer was 0.5 (95% confidence interval, 0.2-1.3) among white women; ORs were not calculated among African Americans because only one participant exhibited the NAT1*11 allele. There was no evidence for combined effects of NAT1*11 and smoking. Unfortunately, the results of both studies of NAT1*11 are imprecise and lack sufficient statistical power to address fully the potential contribution of NAT1*11 to breast cancer. These results illustrate that the limitations imposed by sample size, as well as incomplete knowledge of biological function, need to be considered when planning and interpreting studies of genetic polymorphisms and environmental exposures.     

胸段食管鳞癌根治术后T3以上或淋巴结阳性患者接受辅助治疗的疗效分析

目的探讨胸段食管鳞癌R0切除术后p T3~4N0或p T1~4N1~3患者接受辅助治疗的临床疗效。方法回顾性分析2009年1月至2013年12月间收治的胸段食管鳞癌R0切除术后p T3~4N0或p T1~4N1~3患者接受术后辅助治疗的情况,共入组患者262例,根据术后辅助治疗情况分为单纯手术组(n=111)、辅助化疗组(n=91)和辅助放疗组(n=60)。采用Kaplan-Meier法计算生存率,Cox多因素回归法分析影响患者预后的独立因素。结果辅助放疗组和辅助化疗组患者的中位无病生存期(DFS)均优于单纯手术组(均P<0.05),但辅助放疗组与辅助化疗组间差异无统计学意义(P=0.664)。辅助放疗组和辅助化疗组患者的中位总生存期(OS)均优于单纯手术,差异均有统计学意义(均P<0.05),但辅助放疗组和辅助化疗组间差异无统计学意义(P=0.944)。对于p T3~4N0患者,辅助化疗组OS高于单纯手术组(P=0.042);对于p T1~4N1~3患者,辅助放疗组及辅助化疗组OS均优于单纯手术组(均P<0.05),但辅助放疗组与辅助化疗组差异无统计学意义(P=0.310)。而对于局部浸润较深且淋巴结转移的p T3~4N0患者,辅助放疗组和辅助化疗组OS均优于单纯手术组(均P<0.05),且辅助放疗组也优于辅助化疗组(P=0.011)。Cox多因素回归分析显示,肿瘤部位、肿瘤浸润深度(p T)、病理淋巴结转移个数(p N)、肿瘤分析程度、术后治疗均为影响患者生存的独立预后因素(均P<0.05)。结论对于p T1~4N1~3患者,术后辅助化疗或辅助放疗均可显著改善DFS和OS,其中p T3~4N1~3患者,辅助放疗获益更大。     

Role of UGT1A1*28 and UGT1A1*6 for irinotecan-induced adverse drug reaction

Irinotecan is widely used in the treatment of colorectal, gastric, and lung cancers. However, adverse drug reactions such as severe diarrhea and neutropenia limit the dose of this drug. Irinotecan is metabolized by carboxylesterase to form an active metabolite, 7-ethyl-10-hydroxycamptothecin(SN-38), which in turn is subsequently conjugated by UGT-glucuronosyltransferase 1A1(UGT1A1)to yield an inactive form, SN-38 glucuronide(SN-38 G). The UGT1A1 gene polymorphisms contribute to the individual variation in adverse events among patients administered irinotecan. However, the distribution of polymorphisms shows large interethnic differences. The distribution of UGT1A1*28 greatly differs between Caucasians and Japanese; the frequency of UGT1A1*28 is high in Caucasians, whereas it is low in Asians including Japanese. Recently, it has been demonstrated that genetic variants of UGT1A1*6 in addition to UGT1A1*28 are associated with the occurrence of adverse events in irinotecan chemotherapy in Asians. This review summarizes recent studies to outline the role of UGT1A1*28 and UGT1A1*6 for irinotecan-induced adverse drug reaction in Japanese cancer patients.     

CYP2E1*5B,CYP2E1*6, CYP2E1*7B,CYP2E1*2, and CYP2E1*3 Allele Frequencies in Iranian Populations

Background: CYP2E1 encodes an enzyme which is mainly involved in bioactivation of potential carcinogenssuch as N-nitrosamines. Polymorphisms in the gene have been reported to be associated with cancer. The aim ofthis study was to evaluate genotype distributions and allele frequencies of five CYP2E1 polymorphisms in IranMaterials and Methods: Two hundred healthy individuals of an Iranian population from the southwest wereincluded in this study. PCR-restriction fragment length polymorphism and Tetra-ARMS PCR methods wereapplied for CYP2E1 genotyping. Results: The allele frequencies for *5B, *6, *7B, *2, and *3 were calculated tobe 1.5%, 16%, 28.5%, 0%, and 2.75% respectively. Results of this study showed that no significant differencesin genotype and allele frequencies of five single nucleotide polymorphisms with respect to the gender andtribes. The chi-square test showed that the genotype frequencies of CYP2E1*5B were similar to Caucasians,but the distribution of CYP2E1*6 genotypes was similar to Asians. The frequencies of CYP2E1*2 (0%) andCYP2E1*3 (2.75%) alleles were within the range for Caucasians and Orientals. In the case of CYP2E1*7B, thedata werelimited. Accordingly, the results were only compared with Europeans and the comparison showedsignificant differences. Conclusions: In conclusion, ethnic and geographic differences may explain discrepanciesin the prevalence of CYP2E1 polymorphisms.     

Linkage disequilibrium of UGT1A1 *6 and UGT1A1 *28 in relation to UGT1A6 and UGT1A7 polymorphisms

UDP-glucuronosyltransferase (UGT) enzymes are responsible for the glucuronidation and detoxification of many endogenous or exogenous xenobiotics. Gilbert's syndrome (GS) and Crigler Najjar syndrome type 2 (CNS-II) are characterized by unconjugated hyperbilirubinemia due to reduced enzymatic activity of UGT1A1. Recent studies have demonstrated the frequent co-existence of UGT1A1 *28 (-53 [TA]6>7) with other polymorphisms of UGT1A6 and UGT1A7. This finding suggests the occurrence of linkage disequilibrium (LD) among UGT1A1, UGT1A6 and UGT1A7 polymorphisms. UGT1A1 *6 (211G>A, G71R) and UGT1A1 *28 are common in Asian populations. In the present study, we investigated the LD of UGT1A1 *6 and UGT1A1 *28 in relation to UGT1A6 and UGT1A7 polymorphisms. Exon 1 of UGT1A1, UGT1A6 and UGT1A7 was sequenced using genomic DNA isolated from peripheral leukocytes of 390 Japanese subjects. LD and haplotypes were analyzed using SNPAlyze ver. 5.0 software. UGT1A1 *6 had a strong LD in relation to UGT1A6 variants including 541A>G and 552A>C (D'=0.846-0.848, r(2)=0.413-0.438) and UGT1A7 variants including 387T>G, 391C>A, 392G>A and 622T>C (D'=0.667-0.858, r(2)=0.207-0.413). UGT1A1 *28 had a lower degree of LD than UGT1A1 *6 in relation to these variants (D'=0.245-0.401, r(2)=0.025-0.063). All the haplotypes with G71R lacked -53[TA]6>7. The present study showed for the first time that the LD of UGT1A1 *6 in relation to UGT1A6 and 1A7 polymorphisms is far stronger than UGT1A1 *28. The UGT1A1 *6 allele appears to be independent of the UGT1A1 *28 allele. Although patients with GS and CNS-II are believed to have good prognosis, a subgroup of GS or CNS-II patients with the UGT1A1 *6 polymorphism might be at risk of abnormal drug metabolism and of developing malignant disease.     

Associations between UGT1A1*6 or UGT1A1*6/*28 polymorphisms and irinotecan-induced neutropenia in Asian cancer patients

Purpose

Neutropenia is a life-threatening side effect of irinotecan, and uridine diphosphate glucuronosyltransferases (UGTs) gene polymorphisms are considered to be one of the predictive markers of irinotecan-related toxicities. Many studies have demonstrated that patients bearing UGT1A1*28 have a higher risk of severe neutropenia on toxicity of irinotecan. However, UGT1A1 (TA7/TA7) was very rare in Asian populations. Some researches reported that UGT1A1*28 and/or UGT1A1*6 could predict irinotecan-induced toxicities in Asian populations, but controversial conclusions still remained. This study aims to investigate the association between UGT1A1 gene polymorphisms *6, *6/*28 and irinotecan-related neutropenia in Asian cancer patients receiving irinotecan regimen chemotherapy.

Experimental design

Meta-analyses were done to assess the relationship between UGT1A1*6 or UGT1A1*6/*28 and irinotecan-induced neutropenia.

Results

The risk of neutropenia was significantly higher among patients with a UGT1A1*6 genotype than among those carrying the UGT1A1*1 allele(s) [odds ratio (OR) 3.276; 95 % confidence interval (CI) 1.887–5.688; P = 0.000 (*6/*6 vs. *1/*6 or *1/*1)], [OR 1.542; 95 % CI 1.180–2.041; P = 0.001 (*6/*6 or *1/*6 vs. *1/*1)]. Also, the risk was significantly higher among patients with a UGT1A1*6/*28 than among those carrying the UGT1A1*1 allele(s) [OR 3.275; 95 % CI 2.152–4.983; P = 0.000 (*6/*6 or *28/*28 or *6/*28 vs. *1/*6 or *1/*28 or *1/*1)].

Conclusions

In conclusion, the UGT1A1*6 and UGT1A1*6/*28 genotypes were associated with an increased risk of irinotecan-induced neutropenia in Asian cancer patients.     

Association between high-risk HPV types, HLA DRB1* and DQB1* alleles and cervical cancer in British women

Cervical scrapes from 116 British women referred with cervical cancer were tested for the presence of high oncogenic risk human papillomavirus (HPV) genotypes (HPV(hr)). Ninety-four per cent of the scrapes had one or more of these virus types and 66% were HPV16-positive. HPV18 was more frequent in adenocarcinoma. No evidence was found for an increased cancer risk associated with the HPV16 E6 350G variant. The HLA DRB1* and DQB1* alleles in these women and in 155 women with normal cytology and negative for HPV(hr) DNA were compared. DQB1*0301 alone (2P = 0.02) and in combination with DRB1*0401 (2P = 0.02) was found to be associated with cervical cancer. This was more marked in cancers positive for HPV types other than HPV16. In contrast, DRB1*1501 alone and in combination with DQB1*0602 was not significantly elevated in cancers overall, but did show some excess in HPV16-positive cancers (2P = 0.05), associated with HPV16-positive cervical cancers. Taking all cancers together, a marginally significant protective effect was found for DQB1*0501 (2P = 0.03) but no protective effect could be seen for DRB1*1301.     

Genotype-directed, dose-finding study of irinotecan in cancer patients with UGT1A1*28 and/or UGT1A1*6 polymorphisms

Irinotecan-induced severe neutropenia is associated with homozygosity for the UGT1A1*28 or UGT1A1*6 alleles. In this study, we determined the maximum-tolerated dose (MTD) of irinotecan in patients with UGT1A1 polymorphisms. Patients who had received chemotherapy other than irinotecan for metastatic gastrointestinal cancer were enrolled. Patients were divided into three groups according to UGT1A1 genotypes: wild-type (*1/*1); heterozygous (*28/*1, *6/*1); or homozygous (*28/*28, *6/*6, *28/*6). Irinotecan was given every 2 weeks for two cycles. The wild-type group received a fixed dose of irinotecan (150 mg/m(2)) to serve as a reference. The MTD was guided from 75 to 150 mg/m(2) by the continual reassessment method in the heterozygous and homozygous groups. Dose-limiting toxicity (DLT) and pharmacokinetics were evaluated during cycle 1. Of 82 patients enrolled, DLT was assessable in 79 patients (wild-type, 40; heterozygous, 20; and homozygous, 19). Dose-limiting toxicity occurred in one patient in the wild-type group, none in the heterozygous group, and six patients (grade 4 neutropenia) in the homozygous group. In the homozygous group, the MTD was 150 mg/m(2) and the probability of DLT was 37.4%. The second cycle was delayed because of neutropenia in 56.3% of the patients given the MTD. The AUC(0-24 h) of SN-38 was significantly greater (P < 0.001) and more widely distributed in the homozygous group. Patients homozygous for the UGT1A1*28 or UGT1A1*6 allele can receive irinotecan in a starting dose of 150 mg/m(2), but many required dose reductions or delayed treatment in subsequent cycles. UMIN Clinical Trial Registration number: UMIN000000618.     

Real-time PCR analysis of the N-acetyltransferase NAT1 allele *3, *4, *10, *11, *14 and *17 polymorphism in squamous cell cancer of head and neck

Although tobacco smoke has been established as a main risk factorin the development of head and neck squamous cell cancer (HNSCC),genetic polymorphisms of xenobiotic metabolizing enzymes aresupposed to modulate an individual's susceptibility to smoking-relatedHNSCC. N-acetyltransferase (NAT) 1 gene is known to be polymorphicand its protein product is implicated in the activation anddetoxification of carcinogens, such as aromatic amines, presentin tobacco smoke. We developed a rapid and reproducible LightCycler^TM-assistedreal-time polymerase chain reaction (PCR) for NAT1 genotyping,which allowed the parallel differentiation of NAT1*3, *4, *10and *11 alleles and separately of NAT1*14 and *17 alleles within60 min without the need for further post-PCR processing. Inorder to investigate the role of the NAT1 gene polymorphismas a risk-modifying factor in HNSCC, we tested for the presenceof NAT1*3, *4, *10, *11, *14 and *17 alleles in a case-controlstudy of 291 HNSCC patients and 300 healthy controls of Caucasianorigin. Our findings suggest that in Caucasians, the risk ofHNSCC is not associated with NAT1 polymorphism. The overalldistribution of NAT1 allele frequencies was not significantlydifferent among cases and controls. The presence of the fastacetylator NAT1*10 and NAT1*11 alleles did not significantlyincrease the risk of HNSCC and no modifying effect of NAT1*10was observed among smokers. This new approach in NAT1 genotypingsubstantially increases throughput of sample analysis and, therefore,enhances opportunities to study NAT1 as a risk factor in differentcancers in large-scale studies.