ERCC1和XRCC1基因多态性与接受奥沙利铂化疗晚期大肠癌患者生存期的关系

目的:探讨DNA损伤修复基因ERCC1 Asn118Asn和XRCC1 Arg399Gln多态性与接受奥沙利铂一线化疗的中国晚期大肠癌患者生存期的关系.方法:99例晚期大肠癌患者化疗前抽取静脉血并提取DNA,以real-time PCR法对ERCC1、XRCC1基因进行SNP分型.患者接受奥沙利铂为主的化疗方案化疗,比较不同基因型与患者生存期的关系.结果:ERCC1 Asn118Asn基因位点在所研究的中国大肠癌患者中的突变频率为:C/C 50.51%、C/T 41.41%、T/T8.08%;XRCC1 Arg399Gln基因突变频率为:G/G 52.53%、G/A 38.38%、A/A 9.09%.99例晚期大肠癌患者中位TTP为7个月.ERCC1C/C基因型患者中位TTP 10个月,C/T T/T型患者中位TTP 5个月,二者有显著统计学差异(P<0.01);XRCC1G/G基因型中位TTP 10个月,G/A A/A基因型中位TTP 5个月,二者比较差异有显著性(P<0.01).两个基因联合多态性分析发现,同时携带ERCC1 C/C和XRCC1 G/G基因型、ERCC1 C/C和XRCC1 G/A A/A基因型、ERCC1 C/T T/T和XRCC1 G/G基因型、以及ERCC1 C/T T/T和XRCC1 G/A A/A基因型的患者中位TTP分别为11个月、6个月、5个月和5个月,4组比较差异有显著性(P<0.01).结论:ERCC1 Asn118Asn、XRCC1 Arg399Gln基因多态性与中国晚期大肠癌患者接受奥沙利铂一线化疗后的生存期有关.     

ERCC1和XRGC1基因多态性与接受奥沙利铂化疗晚期大肠癌患者生存期的关系

目的：探讨DNA损伤修复基因ERCC1 Asn118Asn和XRCC1 Arg399Gln多态性与接受奥沙利铂一线化疗的中国晚期大肠癌患者生存期的关系。方法：99例晚期大肠癌患者化疗前柚取静脉血并提取DNA，以real-time PCR法对ERCC1、XRCC1基因进行SNP分型。患者接受奥沙利铂为主的化疗方案化疗，比较不同基因型与患者生存期的关系。结果：ERCC1 Asn118Asn基因位点在所研究的中国大肠癌患者中的突变频率为：C／C50．51％、C／T41．41％、T/T 8．08％；XRCC1 Arg399Gln基因突变频率为：G／G52．53％、G／A38．38％、A／A9．09％。99例晚期大肠癌患者中位TTP为7个月。ERCC1C／C基因型患者中位TTP 10个月，C/T＋T/T型患者中位TTP 5个月，二者有显著统计学差异（P〈0．01）；XRCC1G／G基因型中位TTP 10个月，G／A＋A／A基因型中位TTP 5个月，二者比较差异有显著性（P〈0．01）。两个基因联合多态性分析发现，同时携带ERCC1C／C和XRCC1G／G基因型、ERCC1C／C和XRCClG／A＋A／A基因型、ERCC1C／T＋唧和XRCC1G／G基因型、以及ERCC1 C／T＋T/T和XRCC1G／A＋A／A基因型的患者中位TTP分别为11个月、6个月、5个月和5个月，4组比较差异有显著性（／9〈0．01）。结论：ERCC1 Asn118Asn、XRCC1 Arg399Gln基因多态性与中国晚期大肠癌患者接受奥沙利铂一线化疗后的生存期有关。     

DNA修复基因多态性与肺癌顺铂化疗敏感性的研究

目的:研究切除修复交叉互补基因1(excision repair cross-complementing gene 1,ERCC1)Asn118Asn、切除修复交叉互补基因2(excision repair cross-complementing gene 2,ERCC2)Lys751Gln和X线修复交叉互补基因1(X-ray repair cross complementing group 1,XRCC1)Arg399Gln单核苷酸多态性与非小细胞肺癌(non-small cell lung cancer,NSCLC)对铂类药物化疗敏感性的相关性。方法:采用基因测序的方法,检测89例以铂类药物为主要化疗方案的NSCLC患者外周血DNA中ERCC1基因Asn118Asn、ERCC2基因Lys751Gln和XRCC1基因Arg399Gln的基因型;采用统计学方法分析不同基因型与化疗疗效的相关性。结果:89例NSCLC患者采用铂类药物化疗总有效率为29.2%;ERCC1基因Asn118Asn和ERCC2基因Lys751Gln基因型在化疗有效组和无效组之间的分布,差异无统计学意义(P>0.05);而携带XRCC1基因Arg399Arg与携带至少1个Gln等位基因(Arg399Gln和Gln399Gln)基因型患者的有效率分别为76.9%和23.1%(χ2=11.1,P=0.001)。携带XRCC1基因Arg399Arg基因型患者对化疗的敏感性明显高于携带至少1个Gln等位基因型的患者(比值比为5.228,95%可信区间为1.776～15.387,P=0.003)。ERCC1、ERCC2和XRCC1基因型的联合可以提高化疗的有效率。结论:ERCC1、ERCC2和XRCC1基因的单核苷酸多态性的联合可能与NSCLC对铂类药物化疗敏感性具有相关性。     

ERCC1和XRCC1多态性与进展期非小细胞肺癌对铂类化疗的敏感性

目的探讨DNA修复基因ERCC1 118C/T和XRCC1 Arg194Trp多态性与进展期非小细胞肺癌(non-small cell lung cancer,NSCLC)患者铂类药物化疗敏感性的关系。方法采用PCR-RFLP技术检测149例经病理确诊的接受含铂两药方案化疗的NSCLC患者外周血ERCC1 118和XRCC1 194位点的基因型,并分析其与化疗疗效的关系。结果经2个周期化疗后,149例进展期NSCLC患者化疗有效率为32.9%。携带至少1个ERCC1 118T突变基因患者的化疗有效率至少是C/C野生型基因携带者的3倍(49.1%vs 23.4%,OR=3.156,95%CI:1.548～6.334,P=0.001)。携带至少1个XRCC1 194Trp突变基因患者的化疗有效率显著高于Arg/Arg基因型携带者(41.3%vs 23.2%,OR=2.326,95%CI:1.138～4.753,P=0.019)。ERCC1 118C/T和XRCC1 Arg194Trp 2个基因多态之间存在一定的联合作用,携带至少1个ERCC1 118 T突变基因同时又携带至少1个XRCC1 194Trp突变基因型者的化疗有效率明显高于同时携带ERCC1 118C/C和XRCC1 194Arg/Arg野生型基因者(66.7%vs 17.1%,OR=9.714,95%CI:3.104～30.406,P<0.001)。结论与单基因检测比较,2个基因的联合检测在预测铂类药物化疗敏感性中的价值更大。ERCC1 118和XRCC1 194基因多态联合与NSCLC患者对铂类药物化疗敏感性相关,ERCC1和XRCC1基因型的联合检测有可能成为预测铂类药物化疗敏感性的指标。     

晚期大肠癌患者血清XRCC1基因多态性与奥沙利铂化疗疗效相关性的研究

目的:探讨XRCC1Arg399Gln(G→)基因多态性与晚期大肠癌对以臭沙利铂为主的化疗敏感性的关系.方法:晚期大肠癌患者99例(Ⅲ期37例,Ⅳ期62例),以奥沙利铂为主的方案化疗,62例Ⅳ期患者2～3个周期后进行临床疗效评价,99例患者统计至疾病进展时间(TTP).应用TaqMan-MGB探针等位基因分型技术进行基因分型.结果:52.53%为G/G,9.09%为A/A,38.38%为G/A.Ⅳ期62例患者化疗后临床获益率(CR PR SD)为54.84%,G/G、G/A A/A在化疗敏感组与不敏感组中的分布具有统计学意义(x2=6.513,P=0.21;OR=3.870,95%CI=1.341～11.172,P=0.012).99例患者中位TTP 7个月,G/G基因型10个月,G/A A/A基因型5个月,两者比较差异有统计学意义,x2=29.20,P<0.01.结论:XRCC1 Arg399Gin基因多态性可能与晚期大肠癌患者对奥沙利铂化疗的敏感性与生存时间相关.     

ERCC1和XPD单核苷酸多态性与非小细胞肺癌铂类化疗敏感性的关系

目的：探讨DNA修复基因ERCC1 C118T和XPD Lys751Gln单核苷酸多态性与非小细胞肺癌（non-small-cell lung carcinoma,NSCLC）患者对含铂方案化疗敏感性的关系。方法：选择经病理确诊为NSCLC的患者73例,在实施化疗前采取静脉血,提取DNA,行DNA测序、用PCR-RFLP方法检测ERCC1 C118T和XPD Lys751Gln基因型。所有患者均经含铂方案化疗,观察疗效,统计临床获益率,分析NSCLC患者ERCC1和XPD单核苷酸多态性与含铂方案化疗敏感性的关系。结果：ERCC1 C118TC/C、C/T和T/T基因型临床获益率分别为94.9%、71.4%和83.8%。基因型C/C临床获益率明显高于C/T、T/T（P〈0.05）。XPD Lys751Gln基因型Lys/Lys、Lys/Gln临床获益率分别为80.3%和75.0%。基因型Lys/Lys与Lys/Gln临床获益率间的差异无统计学意义（P=0.702）。未检测到XPD Gln/Gln基因型。ERCC1 C118T、XPD Lys751Gln多态之间在对含铂方案的化疗敏感性方面无协同作用（P=0.134和P=0.236）。结论：DNA修复基因ERCC1 C118T单核苷酸多态性与NSCLC含铂方案化疗的敏感性有关,可作为预测NSCLC患者铂类药物化疗敏感性的参考指标之一。     

切除修复交叉互补基因1和X线修复交叉互补基因1及谷胱甘肽巯基转移酶π 1多态性与晚期胃癌患者生存期的关系

目的 探讨切除修复交叉互补基因1(ERCC1)、X线修复交叉互补基因1(XRCC1)和谷胱甘肽巯基转移酶π1(GSTP1)多态性与中国晚期胃癌患者接受含奥沙利铂方案一线化疗后生存期的关系.方法 85例晚期胃癌患者接受奥沙利铂+5-氟尿嘧啶为基础的联合化疗方案化疗,并在化疗前抽取患者静脉血,提取基因组DNA,以实时荧光定量PCR法行多态性检测,比较不同基因型与患者生存期的关系.结果 85例患者中位至疾病进展时间为5.3个月,中位生存期为8.0个月.ERCC1-118 C/C、XRCC1-399 G/G和GSTP1-105 A/G+G/G基因型为优势基因型,携带3个、2个、1个、0个优势基因型患者的中位生存期分别为12.5、10.0,6.5和4.5个月,组间差异有统计学意义(χ2=35.54,P<0.01).结论 ERCC1-118、XRCC1-399和GSTP1-105基因多态性与中国晚期胃癌患者接受含奥沙利铂化疗方案一线化疗后的生存期相关,可预测患者的预后.     

ERCC 1和XRCC 1多态与非小细胞肺癌GP方案化疗敏感性的研究

目的:探讨DNA修复酶基因ER-CC1 118和XRCC1 194多态性与非小细胞肺癌(NSCLC)患者对吉西他滨/顺铂(GP)方案化疗敏感性的关系.方法:收集经病理确诊的NSCLC 57例,化疗前均抽静脉血,提取白细胞DNA,用PCR-RFLP技术检测ER-CC1 118和XRCC1 194基因型.患者均经GP化疗方案治疗.结果:1)在NSCLC患者中,ERCC1 118 C/C、C/T和T/T基因型频度分别为48.2%、51.9%和0;XRCC1 194Arg/Arg、Arg/Trp和Tm/Tm基因型频度分别为52.6%、40.4%和7.0%.化疗后,57例患者中19例有效,总有效率为33.3%.2)ERCC1 118 C/C和C/T基因型者的化疗有效率分别为23.1%和46.4%,差异无统计学意义,X2=3.164,P=0.075;XRCC1 194Trp/Trp和Arg/Arg基因型者的化疗有效率分别为50.0%、52.2%和16.7%.携带Trp等位基因者的化疗有效率(51.9%)显著高于A.Rg/Arg基因型者,x2=6.41,P=0.0113.XRCCl 194与ER-CC1 118多态之间在化疗敏感性方面存在明显的交互作用,同时携带XRCC1 194 Arg/Arg和ERCC1 118 C/C基因型者的化疗有效率仅为6.3%(1/16),而携带XRCC1 194Trp等位基因同时携带ERCC1 118 C/C、C/T基因型,其化疗的有效率均显著提高,P=0.011 9和0.007 6.结论:DNA修复酶基因ERCC1 118和XRCC1 194多态与NSCLC对GP方案化疗的敏感性有关,患者的基因型检测有可能作为预测NSCLC对GP方案化疗敏感性的指标.中华肿瘤防治杂志,2009,16(1),27-30     

XRCC1单核苷酸多态性与含铂类药物化疗对肝肾功能影响相关性分析

目的探讨X射线损伤修复交叉互补基因1单核苷酸（XRCC1）多态性与恶性肿瘤患者铂类药物化疗前后肝肾功能变化的关系。方法化疗前采集外周静脉血,采用多聚酶链反应一高温连接酶反应（PCR—LDR）,进行XRCC1 Arg399Gln基因多态性的分型,观察化疗前后患者胆红素、转氨酶、蛋白、GGT、碱性磷酸酶、尿素氮、肌酐、尿酸等多项指标改变情况。结果携带XRCC1 399 Gln/Gln基因型患者,含铂类药物化疗前后总蛋白量的改变幅度低于XRCC1 399 Arg/Gln和XRCC1 399 Arg/Arg者;携带XRCC1 399 Arg/Gln基因型患者,含铂类药物化疗前后尿酸的变化高于XRCC1 399 Gln/Gln和XRCC1 399 Arg/Arg者;含铂类药物化疗前后其余各项肝肾功能指标的变化与XRCC1 Arg 399Gln单核苷酸多态性无关。结论 XRCC1单核苷酸多态性与含铂类药物化疗前后肝肾功能的改变无明显相关性。     

DNA修复酶XRCC1基因多态与非小细胞肺癌对GP方案化疗的敏感性

目的 研究DNA修复酶XRCC1基因Codon 194和Codon 399多态与非小细胞肺癌（NSCLC）患者对吉西他滨/顺铂（GP）方案化疗敏感性的关系.方法 收集经病理学确诊的NSCLC 57例,所有病例化疗前抽静脉血,提取白细胞DNA,用PCR-RFLP技术检测XRCC1 194和399基因型.所有患者均经PDD/GEM化疗方案治疗.结果 ①NSCLC患者中,XRCC1 194 Arg/Arg、 Arg/Trp 、Trp/Trp基因型者分别为30例（52.6%）、23例（40.4%）和4例（7.0%）;XRCC1 399 Arg/Arg、 Arg/Gln、Gln/Gln基因型者分别为31例（54.4%）、23例（40.3%）和3例（5.3%）.经化疗后,19例患者有效,总有效率33.3%.②XRCC1 194 Trp/Trp、Tp/Arg和Arg/Arg基因型者的化疗有效率分别为50.0%、52.2%和16.7%.携带Trp等位基因者的化疗有效率（51.9%）显著高于Arg/Arg基因型者（χ^2=6.41,P=0.0113）;XRCC1 399 Arg/Arg、Arg/Gln和Gln/Gln基因型者的化疗有效率分别为35.5%、34.8%和0,各组间的差异无显著性.XRCC1 194与XRCC1 399多态之间在化疗敏感性方面存在明显的交互作用,同时携带194 Arg/Arg和399 Arg/Arg基因型者的化疗有效率仅为7.7%（1/13）,而同时携带XRCC1 194 Trp等位基因和399 Arg/Arg基因型者的化疗有效率为58.8%（10/17）,2组之间差异显著（Fisher＇s双侧检验：P=0.0067）.结论 DNA修复酶基因XRCC1多态与NSCLC对GP方案化疗的敏感性有关,患者的基因型检测有可能作为预测NSCLC 对GP方案化疗敏感性的指标.     

DNA切除修复交叉互补基因1、乳腺癌易感基因、核苷酸还原酶1与非小细胞肺癌

 阐述了近年来非小细胞肺癌（NSCLC）化疗敏感性与DNA 切除修复交叉互补基因1 （ERCC1）、乳腺癌易感基因（BRCA1）、核苷酸还原酶1（RRM1）基因表达关系的研究进展，分析3个基因对NSCLC个体化化疗潜在的指导意义     

CYP1A1和GSTM1基因多态性与内蒙古人群肺癌易感性的关系

背景与目的 肺癌是严重危害人类健康的恶性肿瘤之一，其发病与肺癌人群中某些肺癌相关基因的遗传多态性有关。本研究旨在探讨细胞色素P4501A1（CYP1A1）基因多态性和谷胱甘肽硫转移酶M1（GSTM1）基因多态性与内蒙古人群肺癌易感性的关系。方法 用PCR-RFLP技术分析了原发性肺癌组和住院对照组（各163例）的CYP1A1、GSTM1基因的多态性、基因型分布频率和交互作用。结果 CYP1A1突变型和GSTM1基因缺陷型EGSTM1（-）]频率分布分别为36．8％、65．0％（病例组）和19．0％、48．9％（对照组），二者经χ^2检验差异有显著性（χ^2=12．82，P=0．000；χ^2=9．78，P=0．002）。CYP1A1突变型患肺癌的风险显著增加（OR=2．48，95％CI为1．51～4．08）。GSTM1（-）者患肺癌的风险也显著增加（OR=2．03，95％CI为1．30～3．17）。基因突变的协同分析发现CYP1A1突变型／GSTM1（-）在肺癌组和对照组中的分布频率分别为28．8％和8．0％，二者经χ^2检验有显著性差异（χ^2=23．883，P=0．000）。CYP1A1突变型／GSTM1（-）患肺癌的风险显著增加（OR=4．90，95％CI为2．50～9．83）。无论是在肺癌组还是在对照组，CYP1A1突变型／GSTM1（-）和CYP1A1非突变型／GSTM1（-）在性别间分布频率的差异均无显著性（肺癌组χ^2=0．797，P=0．372；对照组χ^2=0．670，P=0．761）。吸烟与肺癌易感性的统计学分析，结果显示吸烟与肺癌易感性有关（χ^2=14．197，P=0．000），吸烟者患肺癌的风险显著增加（OR=2．33，95％CI为1.50～3．62）。CYP1A1突变型与吸烟关系的协同分析发现，携带CYP1A1突变型基因的吸烟者较携带CYP1A1突变型基因不吸烟者易患肺癌（OR=4．44，95％CI为2．40～8．32，χ^2=23．843，P=0．000）。GSTM1（-）与吸烟关系的协同分析中也发现，携带GSTM1（-）的吸烟者患肺癌的风险显著增加（OR=7．32，95％CI为3．39～15．50，χ^2=36．708，P=0．000）。结论 CYP1A1突变型和GSTM1（-）是内蒙古地区肺癌的易患因素，二者对肺癌的发生有协同作用，吸烟与肺癌的易感性也有关，CYP1A1突变型、GSTM1（-）与吸烟在肺癌的发生上也有相互促进作用。     

CYP1A1、GSTM1基因多态性及其联合作用与食管癌的易感性

目的探讨CYP1A1、GSTM1基因多态性及其联合作用与新疆汉族人食管癌易感性的关系。方法采用聚合酶链式反应-连接酶检测反应分析方法检测107例食管癌患者和204例非食管癌患者的CYP1A1(rs1048943、rs4646421和rs4646903)和GSTM1(缺失型和rs2071487)的基因型。结果CYP1A1基因rs1048943位点的等位基因和基因型频率在病例组和对照组之间比较,总体分布差异有统计学意义(χ² =5.52,P=0.019)。与A/A基因型相比,GG+AG基因型可增加食管癌的发病风险(OR=1.79,OR95%CI:1.10~2.92);GSTM1基因缺失型和非缺失型在病例组和对照组中的分布频率分别为68.69%、31.31%和48.39%、51.61%,在两组间的分布差异有统计学意义(χ²=10.55,P=0.001;OR=2.34,OR95%CI:1.40~3.91)。结论CYP1A1基因rs1048943位点多态性和GSTM1基因缺失型与新疆地区汉族人食管癌易感性有相关性。     

CYP1A1 (Ile462Val), CYP1B1 (Ala119Ser and Val432Leu), GSTM1 (null), and GSTT1 (null) Polymorphisms and Bladder Cancer Risk in a Turkish Population

We aimed to investigate bladder cancer risk with reference to polymorphic variants of cytochrome p450 (CYP)1A1, CYP1B1, glutathione S-transferase (GST) M1, and GSTT1 genes in a case control study. Polymorphismswere examined in 114 bladder cancer patients and 114 age and sex-matched cancer-free subjects. Genotypes weredetermined using allele specific PCR for CYP1A1 and CYP1B1 genes, and by multiplex PCR and melting curveanalysis for GSTM1 and GSTT1 genes. Our results revealed a statistically significant increased bladder cancerrisk for GSTT1 null genotype carriers with an odds ratio of 3.06 (95% confidence interval=1.39-6.74, p=0.006).Differences of CYP1A1, CYP1B1 and GSTM1 genotype frequencies were not statistically significant betweenpatients and controls. However, the specific combination of GSTM1 null, GSTT1 null, and CYP1B1 codon 119risk allele carriers and specific combination of GSTM1 present, GSTT1 null, and CYP1B1 432 risk allele carriersexhibited increased cancer risk in the combined analysis. We did not observe any association between differentgenotype groups and prognostic tumor characteristics of bladder cancer. Our results indicate that inheritedabsence of GSTT1 gene may be associated with bladder cancer susceptibility, and specific combinations ofGSTM1, GSTT1 and CYP1B1 gene polymorphisms may modify bladder cancer risk in the Turkish population,without any association being observed for CYP1A1 gene polymorphism and bladder cancer risk.     

RB1CC1 activates the promoter and expression of RB1 in human cancer

RB1‐inducible coiled‐coil 1 (RB1CC1, also known as FIP200) is a tumor suppressor implicated in the regulation of RB1 (retinoblastoma 1) expression. However, the molecular mechanism of RB1 regulation by RB1CC1 has not been elucidated. Here, we demonstrate that nuclear RB1CC1 binds to the RB1 promoter using chromatin immunoprecipitation assays with anti‐RB1CC1 antibody. Luciferase assays with RB1 promoter reporter plasmids revealed that RB1CC1 activated the RB1 promoter through the 201 bp upstream GC‐rich region (from the initiation ATG). Electrophoretic mobility shift assay and Western blot analysis supported RB1CC1 binding to the GC‐rich region of the RB1 promoter. In addition, the C‐terminus of RB1CC1 was required for nuclear localization and subsequent RB1 promoter activation. Furthermore, the expression levels of RB1CC1 and RB1 significantly correlated with in vivo breast cancer tissues as determined by immunohistochemical analysis. These data indicate that nuclear RB1CC1 directly activates the RB1 promoter to enhance RB1 expression in cancer cells. Evaluation of RB1CC1 in various types of human cancer tissues is expected to provide useful information for clinical practice and future therapeutic strategies. © 2009 UICC     

Polymorphisms of CYP1A1, GSTM1, GSTT1, and prostate cancer risk in Turkish population

Prostate cancer is the most common cancer among men in many countries. Although the etiology of prostate cancer largely is unknown, both genetic and environmental factors may be involved. Advanced age, androgen metabolism, and heredity-race have been reported to be possible risk factors. On the other hand, several studies indicate that genetic polymorphisms in biotransformation enzymes play a role in prostate cancer development. In this study, association of the prostate cancer risk with genotype frequencies of the Phase I (CYP1A1) and Phase II (GSTM1 and GSTT1) biotransformation enzymes was investigated in 321 Turkish individuals (152 prostate cancer patients and 169 age-matched male controls). The presence or absences of the GSTM1 and GSTT1 genes were determined by a PCR-based method. Genotypes of CYP1A1 were determined by MspI-RFLP. The prevalence of GSTM1 null genotype in the cases was 64 percent, compared to 31 percent in the control group, indicating a strong association (OR = 4.08, 95%CI = 2.50-6.69). No association was observed between either GSTT1 null genotype or CYP1A1 polymorphism and prostate cancer incidence. No statistically significant association was observed between smoking status of the patients and any of the polymorphisms studied. In conclusion, results of this study indicate that only the GSTM1 null genotype may play an important role as a risk factor for prostate cancer development in Turkish population.     

Genetic Variation of GSTM1, GSTT1 and GSTP1 Genes in a South Indian Population

The glutathione S transferase (GST) family of enzymes play a vital role in the phase II biotransformation ofenvironmental carcinogens, pollutants, drugs and other xenobiotics. GSTs are polymorphic and the polymorphismsin GST genes have been associated with cancer susceptibility and prognosis. Moreover, distinct ethnic differenceshave been observed in the type and frequency of GST gene polymorphisms. Hence, the present study was aimed todetermine the frequencies of GSTM1, GSTT1 and GSTP1 polymorphisms in 255 healthy random volunteers fromSouth India. The GSTM1 and GSTT1 genotypes were determined by PCR and GSTP1 by PCR-RFLP using peripheralblood DNA.The GSTM1 and GSTT1 null genotype frequencies were found to be 22.4% and 17.6% respectively. TheGSTP1 allelic frequency was 0.78 for the Ile allele and 0.22 for the Val allele and the genotype frequency was 58.4%for Ile/Ile, 38.4% for Ile/Val, and 3.1% for Val/Val. Comparison of the frequencies of GST polymorphisms observedin the present study with other Indian and world populations revealed a distinctive nature of the South Indianpopulation with respect to polymorphims at the GST gene loci. A better understanding of carcinogen metabolizinggene distribution should contribute to risk assessment of humans exposed to environmental carcinogens.     

VEGFR1和MDR1在胃癌中的表达及意义

目的:探讨VEGFR1和MDR1在胃癌中的表达及意义.方法:采用免疫组化SP法检测VEGFR1和MDR1在胃癌中的表达及与分化程度的关系;比较VEGFR1和MDR1在胃癌中的表达相关性.结果:VEGFR1在高、中、低度分化胃癌的表达率依次为15/53(28%)、19/43(44%)、37/54(68%); 在低分化胃癌组织中的表达明显高于高分化和中分化胃癌组织(P＜0.05).MDR1在高、中、低度分化胃癌的表达率依次为18/53(34%)、21/43(48%)、41/54(76%); 在低分化胃癌组织中的表达明显高于高分化和中分化胃癌组织 (P＜0.05).结论:VEGFR1和MDR1在胃癌中的表达具有一致性,可能在胃癌的多药耐药中扮演重要角色.     

Multiplex PCR with Confronting Two-pair Primers for CYP1A1 Ile462Val,GSTM1, GSTT1, and NQO1 C609T

Polymerase chain reaction with confronting two-pair primers (PCR-CTPP) is an effective genotyping method ‍for single nucleotide polymorphisms (SNPs) in aspects of reducing time and costs for analysis. So far we have ‍established PCR-CTPP conditions for tens of SNPs, including a triplex genotyping (Kawase et al., 2003). In the ‍present study we report a quadruplex PCR-CTPP to genotype simultaneously four functional polymorphisms of ‍carcinogen-metabolizing enzymes, CYP1A1 Ile462Val, GSTM1 null, GSTT1 null and NQO1 C609T, which were ‍reported that they have significant associations with smoking-related cancers. We applied this method for 475 health ‍check-up examinees to demonstrate the performance. Among the subjects, the genotype frequency of CYP1A1 ‍Ile462Val was 56.8% for Ile/Ile, 38.1% for Ile/Val and 5.1% for Val/Val. The null type frequencies of GSTM1 and ‍GSTT1 were 52.8% and 49.9%, respectively. And the genotype frequency of NQO1 C609T was 41.9% for C/C, ‍41.3% for C/T and 16.8% for T/T. Their distributions were similar to those reported for Japanese by other studies. ‍To the best of our awareness, this is the first paper that reports the success in quadruplex PCR-CTPP. The applied ‍polymorphisms are useful ones, which would be adopted not only for research purposes, but also for risk assessment ‍of individuals exposed to carcinogenic substances. This convenient genotyping would be applied for cancer prevention ‍especially in Asian Pacific regions, where expensive genotyping methods are hardly available.