中国人群细胞色素P4501A1基因MSPⅠ位点联合GSTM基因多态性与肺癌易感性的荟萃分析

目的 用荟萃(Meta)分析探讨中国人群细胞色素P4501A1 (CYP1A1)基因MSP Ⅰ位点联合GSTM基因位点多态性对肺癌的形成作用。方法 制定文献纳入和排除标准,双人独立全面检索相关文献,根据纳入标准列出不同基因型组合的个体发生肺癌的优势比（OR）值和95％可信区间(CI),进行异质性检验并根据异质性检验结果采用不同的模型（固定效应模型、随机效应模型）合并OR值、95％CI和P值。结果共纳入12篇文献,涉及13个人群,以CYP1A1基因(w/w)、GSTM基因(+)为参照,CYP1A1基因(w/m)、GSTM基因(+),CYP1A1基因(m/m)、GSTM基因(+),CYP1A1基因(wlw)、GSTM基因（-）,CYP1A1基因(w/m)、GSTM基因（-）,CYP1A1基因(m/m)、GSTM基因（-）的发生肺癌的风险合并值OR及95％CI分别为(1.22,0.95～1.57),(1.24,0.88～1.76),(1.51,1.07～2.12),(1.82,1.30～2.54),(2.06,1.56～2.72)。结论 CYP1A1基因突变型（杂合子和纯合子）联合GSTM基因缺失型可显著增加个体的肺癌发生风险,在肺癌筛检过程中要重视对基因型的筛查,做好一级预防。     

韩国人CYP450 1A1、CYP450 2E1和GSTM1、GSTT1、GSTP1基因座遗传多态性分析

目的 调查代谢相关的CYP4501A1、CYP4502E1和GSTM1、GSIT1、GSTP1基因座在韩国人群中的遗传多态性分布状况。方法 采用多重聚合酶链式反应、聚合酶链式反应-限制性片段长度多态性技术，分析300名韩国健康大学生的CYP1A1基因3′端限制性内切酶Msp Ⅰ位点、CYP2E1基因5′端转录调节区Pst Ⅰ位点和GSTM1、GSTT1缺失与存在、GSTP1基因第5外显子BsmA Ⅰ位点的基因型，计算基因型和基因频率。结果 CYP1A1基因型频率为ml／ml型39．7％、ml／m2型49．7％、m2／m2型10．7％，基因频率为ml 0．645、m2 0．355。CYP2E1基因型频率为cl／cl型66．7％、cl／c2型30％、c2／c2型3．3％，基因频率为C1 0．818、C2 0．182。GSTM1基因缺失型频率为53．3％。GSTT1基因缺失型频率为54．7％。GSTP1基因型频率为Ile／Ile型62％、Ile／Val型34．3％、VaL／Val型3．7％，基因频率为Ile 0．792、Val 0．208。基因分布符合Hardy-Weirtberg平衡定律。结论 韩国人CYP1A1、CYP2E1、GSTM1、GSTT1基因分布与我国人群较为相近，半数以上人缺乏GSTM1和GSTT1基因，纯合缺失型频率超过印度人的3倍。     

CYP1A1基因多态性与妊娠期肝内胆汁淤积症相关性研究

目的 探讨参与雌激素代谢的细胞色素P4501A1(cytochrome P450 1A1,CYPlA1)基因多态性与成都地区妊娠期肝内胆汁淤积症(intrahepatic cholestasis of pregnancy,ICP)的关系.方法 分别应用聚合酶链反应.限制性片段长度多态性技术和等位基因特异性PCR技术,对100例ICP患者和100名正常对照孕妇CYP1A1基因Msp I位点和Ile/Val位点多态性进行分析.结果 Msp I位点多态性在ICP组和对照组中的分布差异无统计学意义(P》0.05),而ICP组含Val等位基因的Ile/Val和Val/Val基因型增加ICP的发病风险(P=0.047,OR=1.768).结论 CYP1A1基因第7外显子的Ile/Val基因多态性可能与成都地区ICP易感性有关;而Msp I位点多态性与ICP的发生无相关性.     

CYP1A1和GSTM1基因多态性与BPDE-DNA加合物的关系及其对肺癌的影响

目的 分析代谢酶基因细胞色素氧化酶P450(cytochrome P450,CYP450)1A1与谷胱苷肽硫转移酶M1(glutathione S-transferase μ1,GSTM1)的多态性和二羟环氧苯并芘(benzo A-pyrene-diolepoxide,BPDE)-DNA加合物之间的关系,并探讨其对肺癌发病的影响.方法 用病例-对照方法收集200例原发性肺癌患者的流行病学调查资料及外周血样本,采用限制性片段长度多态性-PCR法检测血中CYP1A1、GSTM1基因多态性,应用竞争性酶联免疫吸附法检测BPDE-DNA加合物浓度.结果 CYP1A1变异型吸烟者、GSTM1缺失型吸烟者患肺癌风险升高,OR值分别为2.406(1. 321～4. 382)和2.755(1.470～5.163).肺癌患者BPDE-DNA加合物浓度高于对照人群,且肺癌吸烟者加合物浓度明显高于肺癌不吸烟者(P=0.0252);GSTM1缺失型个体DNA加合物水平高于5.0加合物/108核苷酸时,患肺癌的风险升高(OR=1.988,95％ CI:1.011～3.912);CYP1A1变异型吸烟者形成高水平DNA加合物的风险明显高于CYP1A1野生型不吸烟者(P=0.0459); GSTM1缺失型吸烟者形成高水平DNA加合物的风险高于GSTM1功能型不吸烟者(OR=2.432,95％ CI:1.072～4.517).结论 GSTM1缺失型个体DNA加合物水平高更容易增加肺癌危险性;CYP1A1变异型吸烟者、GSTM1缺失型吸烟者更容易形成高水平的DNA加合物,对肺癌的发生可能有重要影响.     

GSTM1、GSTT1缺失和GSTP1基因多态性与原发无精症的相关性研究

目的 探讨谷胱甘肽硫转移酶(glutathione S-transferase,GST)基因家族中GSTM1、GSTT1缺失和GSTP1多态性与汉族人群原发性无精子症的相关性.方法 采用病例对照研究的方法,应用多重PCR及PCR-限制性片段长度多态性技术检测236例汉族原发无精症患者和142名正常生育男性的GSTM1、GSTT1基因缺失和GSTP1基因(Ile/Val)多态性.结果 M1(-/-)和P1(Ile/Val或Val/Val)联合基因型在对照组中分布为24.65％(35/142),高于病例组的15.68％(37/236),差异有统计学意义(P=0.031)；M1(-/-),T1(+/+)和P1(Ile/Val或Val/Val)联合基因型在对照组中分布为12.68％ (18/142),高于病例组的5.51％(13/236),差异有统计学意义(P=0.014).结论 M1(-/-)和P1(Ile/Val或Val/Val)联合基因型以及M1(-/-),T1(+/+)和P1(Ile/Val或Val/Val)联合基因型可能降低男性患无精症的风险.     

多巴胺β羟化酶基因多态性与帕金森病遗传易感性

目的 探讨多巴胺β羟化酶(dopamine beta hydroxylase,DBH)基因内含子5Taq I多态性与帕金森病遗传易感性的关系。方法 用聚合酶链反应—限制性长度片段多态性技术检测了144例原发性帕金森病患者和年龄及性别相匹配的188名健康人多巴胺β羟化酶基因内含子5Taq I多态性。结果 与健康人比较，帕金森病患者DBH基因内含子5Taq I基因型(A1／A2，A2／A2)或等位基因(A1，A2)的分布不同，两组之间的差异有显著性(基因型：A1／A2 OR＝0．45，Z＝10．11，P＜0．015 A2／A2 OR＝2．11，Z＝10．66，P＜0．01；等位基因：A1 OR＝0．54，Z＝10．20，P＜0．01；A2 OR＝1．82，Z＝10．89，P＜0．01)。结论 DBH基因Taq I多态性可能在帕金森病的遗传易感性中起作用。     

细胞代谢解毒酶CYP1A1、GSTM1基因多态性与吸烟对男性肺鳞癌发病的影响

 目的 探讨细胞代谢解毒酶细胞色素P450酶1A1（CYP1A1）、谷胱甘肽S-转硫酶M1（GSTM1）基因多态性和吸烟因素对男性肺鳞癌发病的影响。方法 采用基因芯片技术对125例男性肺鳞癌患者和125例男性健康对照者CYP1A1、GSTM1基因多态性进行检测。结果 CYP1A1 m2位点GG基因型和GSTM1缺失基因型在肺鳞癌组与健康对照者间存在显著性差异(P<0.05 )。吸烟者携带CYP1A1 m2位点至少一个变异G等位基因或携带GSTM1缺失型者患肺鳞癌的危险性进一步显著增加,OR值分别为4.50和3.81(P<0.01)。结论 吸烟与CYP1A1、GSTM1基因多态性与男性肺鳞癌的发生有关。     

DNA修复基因XPC Ala499Val、Lys939Gln多态与肺癌易感性

目的 探讨中国人DNA修复基因XPC Ala499Val、Lys939Gln多态与肺癌易感性的关系。方法 以社区为基础的病例对照研究。经组织学确诊的肺癌病例320例,相同地区年龄和性别频数匹配的人群对照322人,以PER为基础的方法进行多态性检测,比较不同基因型与肺癌风险的关系,并探讨吸烟在其中的影响。结果 与携带499 Ala／Ala基因型者比较,携带至少1个499Val等位基因者（即Ala／Val和Val／Val基因型）肺癌风险增加1．54倍（95％CI=1．11～2．14）,而同时有499和939两个位点变异等位基因者肺癌风险增加2．55倍（95％CI=1．45～4．52）。交互作用分析显示,XPC 499Val变异基因型与吸烟具有超相乘模型的交互作用,同时有两个位点变异等位基因并吸烟者肺癌风险增加可高达7．36倍（95％CI=3．19～17．0）。结论 XPC Ala499Val和Lys939Gln多态可能与中国汉族人群肺癌遗传易感性有关,并可显著增加吸烟对肺癌的危险性。     

CYP1A1-HincⅡ和GSTT1基因遗传多态性与原发性痛经关系分析

目的 研究原发性痛经的遗传易感性。方法 收集某纺织厂499名新婚女工的资料,采用Logistic回归分析,评价CYP1A1－Hinc II和GSTT1多态性与重度原发性痛经的关系。结果 在未调整环境因素时CYP1A1－Ainc II变异基因型虽对痛经有缓解趋势。但差异无显著性（CYP1A1－Hinc II:OR=0.64 95%CI：0．35－1．17）,而GSTT1变异基因型可增加重度原发性痛经危险性（GSTT1：OR＝1。83,95％,CI：1．04－3．21）。调整潜在环境影响因素后,CY1A1－Hinc II变异基因型显示对原发性痛经有缓解趋势（CYP1A1－Hinc II,OR=0.58,95%,CI:0.31-1.08),但差异仍无显著性,而GSTT1变异基因型仍显示可增加重度原发性痛经的危险性（GSTT1：OR＝2．01,95％,CI：1．12－3．62）。结论 重度原发性痛经与GSTT1遗传多态性相关。     

HER-2基因Ile655Val多态性与结直肠癌易感性分析

目的 探讨HER-2原癌基因Ile655Val多态性与结直肠癌易感性的相关性,及其在自然人群中的分布频率.方法 应用病例对照研究,对浙江省嘉善县292例结直肠癌患者和842名健康对照者采用聚合酶链反应-限制性片段长度多态性方法检测HER-2基因密码子655基因型.结果 结直肠癌组HER-2基因Ile/Val+Val/Val基因型频率(25.34%)和Val等位基因频率(13.36%)均显著高于对照组(18.41%和9.74%)(P<0.05).与Ile/lie基因型携带者相比,Ile/Val+Val/Val基因型携带者患结直肠癌的风险增加(OR=1.54,95%CI:1.11～2.14).HER-2基因多态性与吸烟、饮酒的交互作用OR值分别为1.43(95%CI:0.88～2.30)和1.29(95%CI:0.73～2.29).结论 HER-2基因Ile655Val多态性与结直肠癌易感性相关,但是这种多态性与吸烟、饮酒在结直肠癌发生中不存在交互作用.     

Polymorphisms of CYP1A1 and GSTM1 genes and susceptibility to oral cancer

PURPOSE: Oral cancer is the fifth most common form of cancer in the world and comprises 6.5% of all cancer deaths. Since one of the major risk factors for oral cancer is tobacco use, we hypothesized that polymorphic genes coding for tobacco carcinogen-metabolizing enzymes may play a role in oral cancer susceptibility. MATERIALS AND METHODS: To investigate the association between polymorphisms of the CYP1A1 and GSTM1 genes and risks for oral squamous cell carcinoma (OSCC) in the Korean population, the prevalence of the CYP1A1 Mspl and GSTM1 null polymorphisms were examined in 72 patients with histologically confirmed primary OSCC, as well as in 221 healthy control subjects. RESULTS: A significant risk increase for oral cancer was observed among subjects with the homozygous CYP1A1 (m2/m2) genotype (OR=3.8, 95% CI=1.9-7.7), but not the GSTM1 null genotype (OR=0.7, 95% CI=0.4-1.3). Risk for oral cancer was significantly increased in subjects with the homozygous CYP1A1 (m2/m2)genotype, regardless of smoking history (smokers; OR=4.4; 95% CI=1.2-16.3; non- smokers OR=4.9; 95% CI=1.9-12.5). Using the potentially most protective genotype GSTM1 (+)/CYP1A1 [(m1/m1)+ (m1/m2)] as the reference group, an increased risk for oral cancer was observed among subjects with the GSTM1 (+)/ CYP1A1 (m2/m2) (OR= 2.0, 95% CI=0.8-5.2), and GSTM1 (-)/ CYP1A1 (m2/m2) (OR=4.9, 95% CI=1.5-15.5) genotypes (p < 0.009, (chi2 trend test). CONCLUSION: Our results suggest that individuals with a genotype of CYP1A1 (m2/m2) and GSTM1 (-) are highly susceptible for OSCC and that the CYP1A1 (m2/m2) genotype is closely associated with increased risk of OSCC in Koreans.     

Possible risk modification by CYP1A1, GSTM1 and GSTT1 gene polymorphisms in lung cancer susceptibility in a South Indian population

Susceptibility to lung cancer has been shown to be modulated by inheritance of polymorphic genes encoding cytochrome P450 1A1 (CYP1A1) and glutathione S transferases (GSTM1 and GSTT1), which are involved in the bioactivation and detoxification of environmental toxins. As the incidence of lung cancer is known to differ according to ethnicity, we have conducted a case-control study of 146 South Indian lung cancer patients along with 146 healthy controls, to assess any association between CYP1A1, GSTM1 and GSTT1 polymorphisms, either separately or in combination, with the likelihood of development of lung cancer in our population. The current weight of evidence from our study indicated that the frequency of CYP1A1 MspI homozygous variant alleles was significantly higher in cases (OR=3.178). We observed a considerable difference in the GSTT1 null deletion frequency in this population when compared with other populations (OR=2.472, 95% CI: 1.191–5.094, P=0.014). There was no relative risk in GSTM1 null genotype when analysed singly (P=0.453). Considering genotype combinations, risk of lung cancer increased remarkably significantly in individuals having one variant allele of CYP1A1, GSTM1, or GSTT1, suggesting gene–gene interactions. Rare genotypic combinations (such as CYP1A1 wild GSTM1 or GSTT1 either null; CYP1A1 variant both GSTM1 and GSTT1 present; CYP1A1 variant GSTM1 or GSTT1 either null), were at higher risk compared to the reference group. Moreover, patients who had smoked <20 pack years and harboured the CYP1A1 variant allele or the GSTT1 null genotype also had a significant risk of lung cancer. Hence our study—the first to analyse a South Indian population—suggests the importance of combined CYP1A1, GSTM1 and GSTT1 polymorphisms in the development of smoking-induced lung cancer.     

Polymorphisms of the GSTP1 and GSTM1 genes and PAH-DNA adducts in human mononuclear white blood cells

Glutathione S-transferases (GSTs) are an important part of the protection system against a wide range of potentially harmful chemical compounds. GSTP1 and GSTM1 are mainly involved in detoxification reactions of PAH carcinogenic intermediates produced by cytochrome P450 (CYP). Polymorphism of the GST genes may influence the level of carcinogen-DNA adducts in human tissues and be associated with individual susceptibility to carcinogens. In this study, we examined the effect of common polymorphism in exon 5 (105Ile --> Val) of the GSTP1 gene, alone and in combination with GSTM1-deletion polymorphism, on the level of PAH-DNA adducts measured by (32)P-postlabeling assay in mononuclear white blood cells collected in winter and in summer from a total of 170 healthy volunteers. When GSTP1 genotypes alone were compared, no statistically significant differences in adduct levels were found. However, smokers with GSTM1(null)/GSTP1-AG or -GG combined genotype showed significantly higher adduct levels in summer than carriers of other GSTM1/GSTP1 combinations (5.60 +/- 5.10 vs. 3.45 +/- 4. 28/10(8) nucleotides, P = 0.015). Among smokers carrying GSTP1-AG or -GG genotype, individuals with GSTM1(null) genotype had a significantly higher level of adducts in summer than subjects with GSTM1(+) genotype (5.60 +/- 5.10 vs. 1.82 +/- 1.98/10(8), P = 0.002) and GSTM1(null)/GSTP1-AA genotype carriers (5.60 +/- 5.10 vs. 4.13 +/- 5.84/10(8), P = 0.03). When adduct levels measured either in winter or in the nonsmoker group were considered, no influence of GSTM1/GSTP1 genotypes was found. Our data show that the combined GSTM1 and GSTP1 genetic polymorphisms may modulate PAH-DNA adduct levels in mononuclear WBCs from individuals exposed to specific carcinogenic compounds, e.g., tobacco smoke, in relatively lower-exposure environmental conditions (i.e., in summer).     

Combined analysis of EPHX1, GSTP1, GSTM1 and GSTT1 gene polymorphisms in relation to chronic obstructive pulmonary disease risk and lung function impairment

Smoking is considered as the major causal factor of chronic obstructive pulmonary disease (COPD). Nevertheless, a minority of chronic heavy cigarette smokers develops COPD. This suggests important contribution of other factors such as genetic predisposing. Our objective was to investigate combined role of EPHX1, GSTP1, M1 and T1 gene polymorphisms in COPD risk, its phenotypes and lung function impairment. Prevalence of EPHX1, GSTP1, M1 and T1 gene polymorphisms were assessed in 234 COPD patients and 182 healthy controls from Tunisia. Genotypes of EPHX1 (Tyr113His; His139Arg) and GSTP1 (Ile105Val; Ala114Val) polymorphisms were performed by PCR-RFLP, while the deletion in GSTM1 and GSTT1 genes was determined using multiplex PCR. Analysis of combinations showed a significant association of 113His/His EPHX1/null-GSTM1 (OR=4.07) and null-GSTM1/105Val/Val GSTP1 (OR =3.56) genotypes with increased risk of COPD (respectively P=0.0094 and P=0.0153). The null-GSTM1/ null-GSTT1, 105Val/Val GSTP1/null GSTT1, 113His/His EPHX1/null-GSTM1 and null-GSTM1/105Val/Val GSTP1 genotypes were related to emphysema (respectively P=0.01; P=0.009; P=0.008 and P=0.001). Combination of 113His/His EPHX1/null-GSTM1 genotypes showed a significant association with the decrease of Δ FEV1 in patients (P =0.028).In conclusion, our results suggest combined EPHX1, GSTP1, GSTM1 and GSTT1 genetic polymorphisms may play a significant role in the development of COPD, emphysema and decline of the lung function.     

Genetic polymorphisms of biotransformation enzymes in patients with Hodgkin's and non-Hodgkin's lymphomas.

Considering the role in the metabolism of chemicals played by biotransformation enzymes, we aimed at determining whether any association exists between genetic polymorphisms in CYP1A1, CYP2E1, epoxide hydrolase (EPHX), glutathione S-transferases (GSTM1/P1/T1) and individual susceptibility to lymphomas. PCR-RFLP-based genotyping assays were used to determine the frequency of polymorphisms in CYP1A1 (3'-flanking region), CYP2E1 (5'-flanking region and intron 6), EPHX (exons 3 and 4), GSTM1 (deletion), GSTP1 (exon 5) and GSTT1 (deletion) in a case-control study comprised of 219 patients with morbus Hodgkin (MH) and non-Hodgkin's lymphomas (NHL) and 455 age- and sex-matched healthy individuals. The distribution of genotypes in CYP2E1-intron 6 was significantly different between the control group and all lymphomas (P = 0.03), patients with NHL (P = 0.024), and especially aggressive diffuse NHL (P = 0.007). Grading of NHL seemed to be associated with this polymorphism as well (P = 0.041). The EPHX-exon 3 genotype distribution was significantly different between control males and males with all lymphomas (P = 0.01) or with NHL (P = 0.019). The Val/Val genotype of GSTP1-exon 5 was prevalent in all MH [odds ratio (OR) = 2.08, 95% confidence interval (CI) = 1.05-4.14] and this difference was particularly evident in females (OR = 2.97, 95% CI = 1.16-7.61). A significant difference in the distribution of GSTP1-exon 5 genotypes was found between NHL tumors >5 cm and those <5 cm (P = 0.03). The results suggest that genetic polymorphisms of biotransformation enzymes may play a significant role in the development of lymphoid malignancies.     

Combined effects of glutathione S-transferase polymorphisms and thyroid cancer risk

Since exposure to ionizing radiation, a risk factor for thyroid cancer, may produce genotoxins potentially eliminated by glutathione-S-transferases, we conducted a case control study to evaluate the role of the GSTM1- and GSTT1-null genotypes and GSTP1 polymorphisms in thyroid cancer. The frequency of GSTP1 Ile/Ile, GSTM1-, and GSTT1-null genotypes was increased in cancer patients when compared with control population. Considering the genotypes over-represented in thyroid cancer patients as potential risk genotypes, we carried out an odds ratio (OR) analysis considering the presence of none, one, two, or three risk genotypes. The results obtained showed that the presence of three potentially risk alleles (GSTM1 null, GSTT1 null, and GSTP1 Ile/Ile) lead to a significant OR increase for all the cases, irrespective of the type of tumor (OR=2.91), for papillary (OR=3.64) but not for follicular tumors. The presence of GSTP1 Ile/Ile leads to a significant later age of tumor onset when compared with GSTP1 Ile/Val and Val/Val (P<0.05), suggesting a possible association between GSTP1 Ile/Ile and the age of disease manifestation. These results suggest that combined GST polymorphisms lead to a moderate increased risk for thyroid cancer, especially for the papillary type, and GSTP1 polymorphisms might modulate the age of onset of the disease.