DNA修复基因hOGG1多态与肺癌遗传易感性

背景与目的 :研究修复8_羟基鸟嘌呤的hOGG1基因Ser326Cys多态与中国人肺癌易感性的关系。 材料与方法 :采用病例_对照分子流行病学方法 ,以PCR_限制性片段多态(Restrictionfragmentlengthpolymorphism,RFLP)技术 ,对128名正常对照和124例肺癌患者hOGG1基因第326位点Ser/Cys多态性进行分析 ,并比较不同基因型与肺癌发病危险的关系。 结果: 对照组和肺癌组人群的Cys等位基因频率基本相同(37.5 %和39.9 %) ,但肺癌组的Cys/Cys基因型频率为19.4 % ,高于对照组的10.2 %。与携带Ser/Ser或Ser/Cys基因型者比较 ,携带Cys/Cys基因型个体患肺癌的危险约增加1倍(OR^ =2.12 ,95 %CI=1.03～4.39)。 结论: hOGG1基因Ser326Cys多态可能与中国人肺癌易感性相关 ,可以作为肺癌遗传易感性标志物 ,用于易感个体的预警和预防。     

GSTM1基因多态性与肿瘤遗传易感性研究进展

谷胱甘肽转硫酶(glutathione S-tranferase,GSTs)是一组具有多种生理功能的蛋白质,是与毒物或致癌物的解毒代谢有关的酶类,在机体代谢有毒化合物、保护细胞免受急性毒性化学物质攻击和抑制细胞癌变中起着重要的作用.因此,编码GSTs的GSTM1基因成为近年来研究的热点.最近国内外众多关于GSTM1基因多态性与肿瘤易感性关联的病例对照研究,均提示GSTM1单核苷酸多态性与多个肿瘤的易感性有关.     

NQO1基因多态性与肺癌遗传易感性

目的：探讨依赖还原型辅酶１／２醌氧化还原的酶基因ｃＤＮＡ６００位Ｃ→Ｔ点突变怕致物基因多态必理否与肺癌遗传多态性有关。方法：采用聚合酶锭反应－限制性片段长度多态性（ＰＣＲ－ＲＦＬＰ）的分析方法分析队列 肺癌病人与１３６例健康成人对照组ＮＱＯ１的基因多态性。结果：Ｔ等位基因频率在肺癌组和对照组分别为５４％、４３％,两组有显著差异（Ｐ＝０．０２４）。基因型分布在肺癌组和组之间差异显著（Ｐ＝０．００８）     

DNA损伤修复基因XRCC和hOGG1多态性与肺癌易感性的关系

DNA损伤修复基因的多态性能够改变DNA修复功能和效率,影响肿瘤易感性.许多研究报道DNA损伤修复基因多态性可能与肿瘤易感性有关,其突变在多种肿瘤的发生、发展过程中起着重要作用.另外,DNA损伤修复基因可能与其他基因相互作用,共同影响肿瘤的发生、发展.肺癌是目前在这方面被研究得最多的肿瘤.文章就DNA损伤修复基因XRCC和hOGG1多态性的生物学特点以及这些基因单核苷酸多态性与肿瘤易感性等方面进行了综述,为该基因用于肿瘤的预防、诊治提供理论借鉴.     

XPD基因多态性与非吸烟女性肺癌易感性的关系

背景与目的 着色性干皮病互补基因D（xeroderma pigmentosum group D，XPD）是一种重要的DNA损伤修复基因，其常见的多态是位于751密码子的A→C多态。本研究旨在探讨XPD基因751位点单核苷酸多态性与非吸烟女性肺癌易感性的关系，并探讨油烟暴露与基因多态性交互作用对肺癌风险的影响。方法 采用病例-对照研究方法，纳入非吸烟女性肺癌患者105人和对照105人。以聚合酶链反应-限制性片段长度多态性方法分析XPD基因Lys751Gln多态基因型。结果 携带至少1个751Gln等位基因者患肺癌的风险显著增高，调整OR为2．80（95％CI为1．21～6．48）。携带等位基因751Gln又有油烟暴露的个体患肺癌的风险较两个危险因素单独作用时更高，校正OR为6．85（95％CI为1．69～27．67，P=0．007）。结论 XPD基因Lys751Gln多态是非吸烟女性肺癌的遗传易感因素。携带XPD751Gln等位基因又有油烟暴露的非吸烟女性患肺癌的风险明显增高。     

XRCC1基因多态与肿瘤遗传易感性研究进展

X射线交错互补修复基因1(XRCC1)通过直接与聚合酶β、DNA连接酶Ⅲ和多聚ADP核糖聚合酶形成复合物，共同参与因电离辐射和氧化损伤引起的碱基切除修复和单链断裂修复。XRCC1基因中存在3个单核苷酸多态位点，各位点多态对各种肿瘤遗传易感性的影响不一。现对XRCC1基因多态与某些肿瘤遗传易感性进行综述。     

NAT2基因多态性与膀胱癌遗传易感性的关系

目的　探讨NAT2基因多态性与膀胱癌遗传易感性的关系。方法　以病例对照研究方法 ,采用PCR RFLP技术 ,对 6 9例膀胱癌患者和 88例健康对照者的NAT2基因型进行检测 ,分析NAT2基因型的分布特征。结果　NAT2慢基因型在病例组的频率为 2 6 .1% (18/6 9) ,对照组为 14 .8% (13/88) ,差异有显著性 (P <0 .0 5 ) ,携带慢基因型者患膀胱癌的危险性比携带快基因型者高 2倍。以NAT2快基因型 /不吸烟者为参照 ,慢基因型 /吸烟者患膀胱癌的危险性增加 5 .8倍 (P <0 .0 5 )。在吸烟量 >10PY(1PY =平均每年每天吸烟 2 0支 )的吸烟者中 ,病例组的慢基因型分布频率显著高于对照组 (P <0 .0 5 )。病例组中 ,NAT2基因型与膀胱癌组织分级呈显著相关性 (P <0 .0 5 )。慢基因型在表浅性肿瘤患者中的频率为 12 .8% ,浸润性肿瘤患者则为 5 4 .5 % ,差异有显著性 (P <0 .0 1)。结论NAT2基因多态性与膀胱癌的易感性有关 ,携带慢基因型的人群易患膀胱癌 ,而且肿瘤恶性程度更高。     

环氧化酶-2基因多态性与肿瘤遗传易感性研究进展

环氧化酶-2（cyclooxygenase-2，COX-2）是前列腺素（prostaglandins，PGs）合成过程中的关键限速酶之一，可将花生四烯酸代谢成各种PGs产物，从而维持机体的病理生理过程，参与炎症反应，疼痛反应，与肿瘤的发生、发展密切相关。因此，COX-2基因成为近年来研究的热点。最近国内外众多关于COX-2基因多态性与肿瘤易感性相关的病例对照研究，均表明COX-2单核苷酸多态性与多个肿瘤的易感性相关。这对肿瘤的个体化治疗有一定的指导作用。     

hOGG1基因Ser326Cys多态性与肺癌易感性的meta分析研究

背景与目的就全世界范围内而言,肺癌是一种常见疾病。人8-羟基鸟嘌呤糖苷酶(human8-hydrox-yguanine glycosylase,hOGG1)是一种DNA修复酶,它能特异切除8-羟基鸟嘌呤(8-dihydro-8-oxoguanine,8-OH-G),对损伤的DNA进行修复。hOGG1Ser326Cys基因多态性与癌症易感性的关系一直是研究的热点,而该多态性与肺癌易感性的关系尚存在争议。本研究采用meta分析旨在更好地探讨hOGG1Ser326Cys多态性与肺癌易感性之间的关系。方法使用MEDLINE数据库检索2010年11月以前的相关文献,按照纳入标准,全面搜索含有研究hOGG1Ser326Cys多态性与肺癌易感性相关的信息。由至少两位评论员做独立文献筛选和资料提取,并交叉审核。使用STATA10.1软件进行统计分析。结果根据检索条件,共有22篇文献(包括8,575例肺癌患者和9,484名正常对照个体)被纳入当前的meta分析。分析结果表明22项研究的结果存在明显异质性,当排除不符合Hard-Weinberg平衡定律的两篇文献后,其余的文献呈现出较好的同质性。与hOGG1Ser326相比,Cy...     

Polymorphisms in the Thymidylate Synthase Gene and Risk of Colorectal Cancer

To evaluate the relationship between polymorphisms (28 bp repeated sequences in 5’-UTR and 6-bp ins/del in 3’-UTR) in then thymidylate synthetase gene (TS) and risk of colorectal, colon and rectal cancers, weconducted a case-control study with 315 cases of colorectal cancer and 439 population-based controls in Jiangsuprovince, China. TS genotypes were identified using PCR–RFLP (restriction fragment length polymorphism)methods. Odds ratios (ORs) were estimated with an unconditional logistic regression model. We found that thedistributions of 5’-UTR genotypes in TS were significantly different between controls and male colon cases (χ2=8.25, P = 0.016). Compared with 3R/3R genotype, individuals with the 2R allele were at an increased risk ofcolon cancer (age-, BMI-, smoking- and alcohol drinking-adjusted OR=1.98, 95%CI: 1.11-3.53) among men. Inccontrast, the 6-bp ins/del polymorphism at the TS 3’- UTR did not influence risk of the colorectal, colon andrectal cancers. When combined genotypes for both TS 5’-UTR and 3’-UTR polymorphisms were evaluated,individuals with the 5’-UTR 2R allele had a OR of 3.61 (95%CI: 1.38-9.49) for colon cancer among men withthe 3’-UTR –6bp/-6bp genotype. These results show that the polymorphism of the 28 bp repeated sequences inTS 5’-UTR could influence susceptibility to colon cancer and that there was a coordinated effect between TS3’-UTR and 5’-UTR polymorphisms in increasing risk of colon cancer among Chinese men.     

Nucleotide Excision Repair Capacity and XPC and XPD Gene Polymorphism Modulate Colorectal Cancer Risk

Background

Colorectal cancer (CRC) is leading malignant tumors to occur mainly in industrialized countries, where it exhibits one of the highest mortality rates. Up to 80% of all CRCs characterize a chromosomal instability (CIN) phenotype. The main challenge faced by scientist is to reveal the mechanism of CIN development. An often proposed model is defects in DNA repair in terms of efficiency and genetic variations that modulate the response to stimuli from the environment. The objectives of this research were to determine whether nucleotide excision repair (NER) might affect CRC risk.

DNA修复基因XPD751单核苷酸多态性与 结直肠癌化疗疗效的相关性

 目的 研究结直肠癌患者DNA修复基因XPD751单核苷酸多态性与铂类药物化疗敏感度的关系。方法 经病理学确诊的晚期结直肠癌患者98例,均行草酸铂联合5-氟尿嘧啶的方案（FOLFOX）治疗。所有病例化疗前抽取静脉血并提取DNA,采用多聚酶链反应 限制性片段长度多态性分析（PCR RFLP）技术检测XPD751单核苷酸多态性。比较不同基因型与化疗疗效的关系。结果 （1）XPD751 Lys/Lys、Lys/Gln和Gln/Gln基因型频度分别为76（77.55%）、17（17.35%）和5（5.10%）。（2）XPD751 Lys/Lys、Lys/Gln 和Gln/Gln基因型有效率分别为50.00%、29.41%和20%,比较Lys/Lys、Lys/Gln的有效率,两者之间的差异有统计学意义（χ²=4.04,P<0.05）。在调整性别、年龄及不同转移部位的影响后,XPD751 Lys/Gln基因型患者化疗失败的可能性是Lys/Lys 基因型患者的3.8倍,OR=3.8,95%CI为0.985~14.698。结论 DNA修复基因XPD751单核苷酸多态性与结直肠癌对FOLFOX方案化疗敏感度相关,检测XPD751单核苷酸多态性可能成为预测结直肠癌患者接受FOLFOX方案化疗敏感度的指标。     

Folate-Related Nutrients,Genetic Polymorphisms,and Colorectal Cancer Risk: the Fukuoka Colorectal Cancer Study

One-carbon metabolism plays an important role in colorectal carcinogenesis. Meta-analyses have suggestedprotective associations of folate and vitamin B6 intakes with colorectal cancer primarily based on studies inCaucasians, and genetic polymorphisms pertaining to the folate metabolism have been a matter of interest.Less investigated are the roles of methionine synthase (MTR) and thymidylate synthetase (TS) polymorphismsin colorectal carcinogenesis. In a study of 816 cases and 815 community controls in Japan, we investigatedassociations of dietary intakes of folate, methionine, vitamin B2, vitamin B6, and vitamin B12 with colorectal cancerrisk. The associations with MTR 2756A>G, MTRR 66A>G, and TSER repeat polymorphism were examined in685 cases and 778 controls. Methionine and vitamin B12 intakes were inversely associated with colorectal cancerrisk, but the associations were totally confounded by dietary calcium and n-3 fatty acids. The other nutrientsshowed no association with the risk even without adjustment for calcium and n-3 fatty acids. The TSER 2R allelewas dose-dependently associated with an increased risk. The MTR and MTRR polymorphisms were unrelatedto colorectal cancer risk. There was no measurable gene-gene or gene-nutrient interaction, but increased riskassociated with the TSER 2R allele seemed to be confined to individuals with high folate status. This study doesnot support protective associations for folate and vitamin B6. The TSER 2R allele may confer an increased riskof colorectal cancer. The role of the TSER polymorphism in colorectal carcinogenesis may differ by ethnicity.     

The Relationship Between 6 Polymorphisms of Caveolin-1 Gene and the Risk of Breast Cancer

Background

Caveolae play a role in cell signal transduction, kinetic regulation of transport vesicles, and cellular physiology. In this study, we evaluated the role of caveolin-1 (CAV-1) genotypes in the risk of breast cancer.

Polymorphisms of the XRCC1 and XPD Genes and Breast Cancer Risk: A Case-Control Study

The purpose of this case control study was to evaluate the role of X-ray repair cross-complementing group 1 (XRCC1) and xeroderma pigmentosum group D (XPD) genotypes as genetic indicators of susceptibility to breast cancer (BC). We analysed DNA samples from 114 breast cancer patients and 113 control subjects using polymerase chain reaction-restriction fragment length polymorphism. For the single nucleotide polymorphisms in XRCC1 exon 10 (Arg399Gln, G/A) and XPD exon 23 (Lys751Gln, A/C), no remarkable differences for genotype distribution and allele frequencies were observed between BC group and control group in the study. The genotype frequency for homozygote A/A in XPD exon 6 (Arg156Arg, C/A) were significantly different between BC and control groups (P < 0.0001, odds ratio = 2.14; 95% confidence interval 1.44-3.17). The data indicate a possible role for XPD (Arg156Arg, C/A) polymorphisms in BC susceptibility.     

Meta-analysis of Associations between Interleukin-17 Gene Polymorphisms and Risk of Gastric Cancer

Background: Previous studies have indicated that single nucleotide polymorphisms (SNPs) of the interleukin-17(IL-17) gene are associated with an increased risk of gastric cancer. However, the findings were inconsistent.Materials and Methods: To provide a more reliable estimation of the association between SNPs in the IL-17gene and the susceptibility to gastric cancer, we searched PubMed, CNKI, and Wan Fang databases and selectedfinally six studies covering 2,366 cases and 3,205 controls to perform a meta-analysis. Results: Statistical analysesshowed that an rs2275913 polymorphism within the IL-17A gene was significantly associated with an increasedrisk of gastric cancer using a generalized odds ratio (ORG, a model-free approach). Moreover, we also found thatthe ‘A’ allele carriers of IL-17A rs2275913 had a significant link with clinicopathological features. However, nosignificant positive signals were observed in the association analysis of the rs3748067 and rs763780 polymorphismswith the risk of gastric cancer in IL-17A and IL-17F, respectively. Conclusions: Despite some limitations, thepresent meta-analysis provided a more precise estimation of the relationship between the IL-17 gene SNPs andgastric cancer risk compared with individual studies.     

ZO-1 SNPs与胃癌遗传易感性及预后*

目的：探讨中国福建地区汉族人群中ZO- 1 基因TJP1 4 个已知位点单核苷酸多态性（SNPs）与胃癌遗传易感性及进展和预后的相关性。方法：应用PCR-LDR法检测福建医科大学附属第一医院200 例健康体检个体及220 例原发性胃腺癌患者TJP1基因4 个SNP 位点的基因型。结果：福建地区汉族人群中,TJP-1 SNP rs 7179270 位点稀有等位基因C 的频率为0.2,而其他三个位点（rs 34771010,rs 28578444和rs 41280058）稀有等位基因频率为0.0。TJP1 基因SNP 位点rs 7179270 200 例对照组等位基因C、T 的频率分别为20% 和80% ,胃癌病例组等位基因C、T 的频率为32.6% 和67.4% ;CC、C/T和TT的基因型频率在对照组分别为4% 、32%和64% ,而在病例组为10.9% 、43.2% 和45.9% ,差异具有统计学意义（OR= 1.953,95%CI 1.425～2.677,P<0.001）。 TJP1 rs 7179270位点基因型与胃癌患者的性别、年龄、分化程度、浸润深度、淋巴结转移及手术后生存时间无显著相关（P>0.05）。 结论：TJP1rs 7179270 位点携带等位基因C 的CC和C/T基因型个体的胃癌患病风险提高,提示检测该位点基因型有助于评估胃癌的遗传易感性;TJP1 rs 7179270 位点的基因型频率与临床病理学参数及胃癌患者手术后生存时间无显著相关性,提示TJP1 rs 7179270 位点多态性可能不参与胃癌的进展和预后;TJP1 rs 34771010、rs 28578444和rs 41280058稀有等位基因频率为0.0,推测中国福建地区人群可能无这三个位点的多态性分布。     

Association of XPD and XRCC1 Genetic Polymorphisms with Hepatocellular Carcinoma Risk

Aim: XRCC1 and XPD are two major repair genes involved in nucleotide excision repair (NER), whichis reported to be associated with risk of several cancers. We explored the association of XRCC1 and XPDpolymorphisms with the risk of HCC. Methods: A total of 410 cases with HCC and 410 health controls werecollected. XRCC1 Arg194Trp, XRCC1 Arg399Gln, XPD Lys751Gln and XPD Asp312Asn genotyping wasperformed by duplex polymerase-chain-reaction with the confronting-two-pair primer (PCR-CTPP) method.Results: XRCC1 194Trp/Trp was strongly significantly associated with an increased risk of HCC cancer whencompared with the wide-type genotype (OR=2.26, 95% CI=(1.23-5.38). Individuals carrying the XRCC1 399Gln/Gln showed increased risk of HCC (OR=1.74, 95%CI=1.06-2.74). The XPD 751Gln/Gln and Gln allele genotypewere associated with strong elevated susceptibility to HCC (OR=3.51 and 1.42, respectively). Conclusion: Theseresults suggest that polymorphisms in XRCC1 and XPD may have functional significance in risk of HCC.