Cytochrome P450 2E1 genetic polymorphism and gastric cancer in Changle,Fujian Province

AIM: Genetic polymorphism in enzymes of carcinogen metabolism has been found to have the influence on the susceptibility to cancer. Cytochrome P450 2E1 (CYP2E1) is considered to play an important role in the metabolic activation of procarcinogens such as N-nitrosoamines and low molecular weight organic compounds. The purpose of this study is to determine whether CYP450 2E1 polymorphisms are associated with risks of gastric cancer. METHODS: We conducted a population based case-control study in Changle county, Fujian Province, a high-risk region of gastric cancer in China. Ninety-one incident gastric cancer patients and ninety-four healthy controls were included in our study. Datas including demographic characteristics, diet intake, and alcohol and tobacco consumption of individuals in our study were completed by a standardized questionnaire.PCR-RFLP revealed three genotypes:heterozygote (C1/C2) and two homozygotes (C1/C1 and C2/C2) in CYP2E1. RESULTS: The frequency of variant genotypes (C1/C2 and C2/C2) in gastric cancer cases and controls was 36.3% and 24.5%, respectively. The rare homozygous C2/C2 genotype was found in 6 individuals in gastric cancer group(6.6%), whereas there was only one in the control group (1.1%). However, there was no statistically significant difference between the two groups (two-tailed Fisher's exact test P=0.066). Individuals in gastric cancer group were more likely to carry genotype C1/C2 (odds ratio, OR=1.50) and C2/C2 (OR=7.34) than individuals in control group (chi(2) =4.597, for trend P=0.032). The frequencies of genotypes with the C2 allele (C1/C2 and C2/C2 genotypes) were compared with those of genotypes without C2 allele (C1/C1 genotype) among individuals in gastric cancer group and control group according to the pattern of gastric cancer risk factors. The results show that individuals who exposed to these gastric cancer risk factors and carry the C2 allele seemed to have a higher risk of developing gastric cancer. CONCLUSION: Polymorphism of CYP2E1 gene may have some effect in the development of gastric cancer in Changle county, Fujian Province.

GSTM1,GSTT1,GSTP1 and CYP1A1 genetic polymorphisms and susceptibility to esophageal cancer in a French population:Different pattern of squamous cell carcinoma and adenocarcinoma

AIM:To evaluate the association between CYP1A1 and GSTs genetic polymorphisms and susceptibility to esophageal squamous cell carcinoma(SCC)and esophageal adenocarcinoma(ADC)in a high risk area of northwest of France. METHODS:A case-control study was conducted to investigate the genetic polymorphisms of these enzymes (CYPIAI*2C and GSTP1 exon 7 Val alleles,GSTMI*2/*2 and GSTTl *2/*2 null genotypes).A total of 79 esophageal cancer cases and 130 controls were recruited. RESULTS:GSTMI*2/*2 and CYPIAI*IA/*2C genotype frequencies were higher among squamous cell carcinomas at a level dose to statistical significance(OR =1.83,95% CI 0.88-3.83,P=0.11;OR=3.03,95% CI 0.93-9.90,P=0.07, respectively).For GSTP1 polymorphism,no difference was found between controls and cases,whatever their histological status.Lower frequency of GSTT1 deletion was observed in ADC group compared to controls with a statistically significant difference(OR=13.31,95% CI 1.66-106.92,P<0.01). CONCLUSION:In SCC,our results are consistent with the strong association of this kind of tumour with tobacco exposure.In ADC,our results suggest 3 distinct hypotheses: (1)activation of exogenous procarcinogens,such as small halogenated compounds by GSTT1;(2)contribution of GSTT1 to the inflammatory response of esophageal mucosa,which is known to be a strong risk factor for ADC, possibly through leukotriene synthesis;(3)higher sensitivity to the inflammatory process associated with intracellular depletion of glutathione.

Genetic predisposition to Helicobacter pylori-induced gastric precancerous conditions

Gastric cancer is the most common malignancy of the gastrointestinal tract in East Asian populations and the second most frequent cause of cancer-related mortality in the world. While previous studies have investigated the genetic factors involved in gastric carcinogenesis, there still exist relatively few studies that have investigated the genetic traits associated with the risk of gastric precancerous conditions. In this paper we will review the biology and genetic polymorphisms involved in the genesis of gastric precancerous conditions reported to date and discuss the future prospects of this field of study. The associations of gastric precancerous conditions with polymorphisms in the cytotoxin-associated gene A-related genes (e.g. PTPN11 G/A at intron 3, rs2301756), those in the genes involved in host immunity against Helico-bacter pylori (H. pylori) infection (e.g.TLR4 +3725G/C, rs11536889) or polymorphisms of the genes essential for the development/ differentiation of the gastric epithelial cells (e.g. RUNX3 T/A polymorphism at intron 3, rs760805) have been reported to date. Genetic epide-miological studies of the associations between H. pylori-induced gastric precancerous conditions and other gene polymorphisms in these pathways as well as polymor-phisms of the genes involved in other pathways like oxidative DNA damage repair pathways would provide useful evidence for the individualized prevention of these H. pylori-induced gastric precancerous conditions.

GSTT1,GSTM1 and CYP2E1 genetic polymorphisms in gastric cancer and chronic gastritis in a Brazilian population

AIM:To test the hypothesis that,in the Southeastern Brazilian population,the GSTT1,GSTM1 and CYP2E1 polymorphisms and putative risk factors are associated with an increased risk for gastric cancer. METHODS:We conducted a study on 100 cases of gastric cancer (GC),100 cases of chronic gastritis (CG),and 150 controls (C).Deletion of the GSTT1 and GSTM1 genes was assessed by multiplex PCR.CYP2E1/Pst1 genotyping was performed using a PCR-RFLP assay. RESULTS:No relationship between GSTT1/GSTM1 deletion and the c1/c2 genotype of CYP2E1 was observed among the three groups.However,a significant difference between CG and C was observed,due to a greater number of GSTT1/GSTM1 positive genotypes in the CG group.The GSTT1 null genotype occurred more frequently in Negroid subjects,and the GSTM1 null genotype in Caucasians,while the GSTM1 positive genotype was observed mainly in individuals with chronic gastritis infected with H pylori. CONCLUSION:Our findings indicate that there is no obvious relationship between the GSTT1,GSTM1 and CYP2E1 polymorphisms and gastric cancer.

Analysis of single nucleotide polymorphisms in the region of CLDN2-MORC4 in relation to inflammatory bowel disease

AIM:To investigate a possible genetic influence of claudin(CLDN)1,CLDN2 and CLDN4 in the etiology of inflammatory bowel disease.METHODS:Allelic association between genetic regions of CLDN1,CLDN2 or CLDN4 and patients with inflammatory bowel disease,Crohn's disease(CD)or ulcerative colitis were investigated using both a casecontrol study approach(one case randomly selected from each of 191 Swedish inflammatory bowel disease families and 333 controls)and a family-based study(463 non-Swedish European inflammatory bowel disease-families).A nonsynonymous coding single nucleotide polymorphism in MORC4,located on the same linkage block as CLDN2,was investigated for association,as were two novel CLDN2 single nucleotide polymorphism markers,identified by resequencing.RESULTS:A single nucleotide polymorphism marker(rs12014762)located in the genetic region of CLDN2 was significantly associated to CD(case-control allelic OR = 1.98,95%CI:1.17-3.35,P = 0.007).MORC4 was present on the same linkage block as this CD marker.Using the case-control approach,a significant association(case control allelic OR = 1.61,95%CI:1.08-2.41,P = 0.018)was found between CD and a nonsynonymous coding single nucleotide polymorphism(rs6622126)in MORC4.The association between the CLDN2 marker and CD was not replicated in the familybased study.Ulcerative colitis was not associated to any of the single nucleotide polymorphism markers.CONCLUSION:These findings suggest that a variant of the CLDN2-MORC4 region predisposes to CD in a Swedish population.

Vascular endothelial growth factor polymorphisms and risk of lung cancer

Objective:We investigated the potential association between vascular endothelial growth factor(VEGF) polymorphisms and the risk of lung cancer.Methods:In the case-control study, we used PCR-RFLP technique to determine two VEGF genotypes-2578C/A and 936C/T in 171 lung cancer patients and 172 healthy controls for conformation, and constructed haplotypes of the two gene sites by PHASE1.0 software.Unconditional logistic regression model was used to analyze the statistical association of genontypes or haplotypes in the two groups adjusted by gender and age.Results:Compared with at least one-2578A allele, individuals with-2578CC genotype found associated with a significantly decreased risk of lung cancer P=0.001;adjusted odds ratio(OR), 0.391;95% confidence interval(95% CI), 0.226-0.686.Analyses stratified by gender showed that the combined-2578 CA and AA genotype were also associated with a significantly decreased risk of lung cancer.(P = 0.016;OR = 0.303;95% CI = 0.153-0.601 and P = 0.018;OR = 0.547;95% CI = 0.331-0.903, respectively).The distribution of the two haplotypes(936C/-2578C and 936C/-2578A) were significantly different between case-and-control groups(P = 0.016, OR = 0.317, 95% CI = 0.124-0.809 and P = 0.018, OR = 0.547, 95% CI = 0.331-0.903).Analyses categorized by tumor histology showed that Haplotype C-C was associated with a significantly decreased risk of adenocarcinoma compared with the reference haplotypes.(P = 0.004;OR = 0.237;95% CI = 0.090-0.627).Conclusion:These results suggest that the VEGF polymorphisms may be a critical factor for the risk of lung cancer.

Gene Polymorphisms and Chemotherapy in Non-small Cell Lung Cancer

The phamacogenetics is being used to predict whether the selected chemotherapy will be really effective and tolerable to the patient. Irinotecan,oxidized by CYP3A4 to produce inactive compounds,is used for treatment of various cancers including advanced non small cell lung cancer (NSCLC) patients. CYP3A4*16B polymorphism was associated with decreased metabolism of irrinotecan. Irinotecan is also metabolized by carboxylesterase to its principal active metabolite,SN-38,which is subsequently glucuronidated by UGT1As to form the inactive compound SN-38G. UGT1A1*28 and UGT1A1*6 polymorphisms were useful for predicting severe toxicity with NSCLC patients treated with irinotecan-based chemotherapy. Platinum-based compounds (cisplatin,carboplatin) are being used in combination with new cytotoxic drugs such as gemcitabine,paclitaxel,docetaxel,or vinorelbine in the treatment of advanced NSCLC. Cisplatin activity is mediated through the formation of cisplatin-DNA adducts. Gene polymorphisms of DNA repair factors are therefore obvious candidates for determinants of repair capacity and chemotherapy efficacy. ERCC1,XRCC1 and XRCC3 gene polymorphisms were a useful marker for predicting better survival in advanced NSCLC patients treated with platinum-based chemotherapy. XPA and XPD polymorphisms significantly increased response to platinum-based chemotherapy. These DNA repair gene polymorphisms were useful as a predictor of clinical outcome to the platinum-based chemotherapy. EGFR kinase inhibitors induce dramatic clinical responses in NSCLC patients with advanced disease. EGFR gene polymorphism in intron 1 contains a polymorphic single sequence dinucleotide repeat (CA-SSR) showed a statistically significant correlation with the gefitinib response and was appeared to be a useful predictive marker of the development of clinical outcome containing skin rashes with gefitinib treatment. The other polymorphisms of EGFR were also associated with increased EGFR promoter activity. EGFR gene mutations and polymorphisms were also associated with EGFR kinase inhibitors response and toxicity.

The effects of CYP1A1 gene polymorphism and p16 gene methylation on the risk of lung cancer in a Chinese population

Objective： To investigate the relationship between the genetic polymorphism of CYP1A1 and the genetic susceptibility to lung cancer as well as to study the effects of the methyiation in p16 gene on the risk of lung cancer in a Chinese population. Methods： A case control study was conducted among 47 cases of lung cancer and 94 controls. The genetic polymorphism of CYP1A1 was tested with method of PCR-RFLP, and a methylation-specific PCR （MSP） was performed to detect p16 methylation. Results： It showed that there was no significant difference in frequencies of the genotypes of CYP1A1 between the two groups （P 〉 0.05）. Synergistic effects were not found between smoking and CYP1AI. Methylated p16 gene was found in 44.7% （21/47） of lung cancer tissues and in 17.0% （8/47） of normal lung tissues with significant difference （P 〈 0.05）. Conclusion： The genetic polymorphism of CYP1A1 does not increase the risk of lung cancer in a Chinese population. The methylation in p16 gene may be the most common mechanism to inactivate p16 gene in lung cancer, and is not significantly associated with genotype of CYP1A1,

中国汉族人群Toll样受体2基因多态性与肺结核易感性之间关系

目的检测中国汉族人群特异TLR2基因多态性,并分析与结核病易感性之间关系。方法在小样本中测序检测TLR2基因中可能存在的基因多态性,再用连接酶特异检测技术在大样本进行SNP分型,并通过统计学方法分析基因多态性与结核病易感性之间相关性。结果共检测到6个基因多态性,它们在结核病患者与健康人之间等位基因、基因型以及单配体型上差异无统计学意义(P>0.05)。结论 TLR2基因多态性并不是中国汉族人群结核病发病的重要危险因素。

Pancreatic ductal adenocarcinoma: Risk factors, screening, and early detection

Pancreatic cancer is the fourth most common cause of cancer-related deaths in the United States, with over 38000 deaths in 2013. The opportunity to detect pancreatic cancer while it is still curable is dependent on our ability to identify and screen high-risk populations before their symptoms arise. Risk factors for developing pancreatic cancer include multiple genetic syndromes as well as modifiable risk factors. Genetic conditions include hereditary breast and ovarian cancer syndrome, Lynch Syndrome, familial adenomatous polyposis, Peutz-Jeghers Syndrome, familial atypical multiple mole melanoma syndrome, hereditary pancreatitis, cystic fibrosis, and ataxia-telangiectasia; having a genetic predisposition can raise the risk of developing pancreatic cancer up to 132-fold over the general population. Modifiable risk factors, which include tobacco exposure, alcohol use, chronic pancreatitis, diet, obesity, diabetes mellitus, as well as certain abdominal surgeries and infections, have also been shown to increase the risk of pancreatic cancer development. Several largevolume centers have initiated such screening protocols, and consensus-based guidelines for screening high-riskgroups have recently been published. The focus of this review will be both the genetic and modifiable risk factors implicated in pancreatic cancer, as well as a review of screening strategies and their diagnostic yields.

New genes emerging for colorectal cancer predisposition

Colorectal cancer(CRC)is one of the most frequent neoplasms and an important cause of mortality in the developed world.This cancer is caused by both genetic and environmental factors although 35%of the variation in CRC susceptibility involves inherited genetic differences.Mendelian syndromes account for about5%of the total burden of CRC,with Lynch syndrome and familial adenomatous polyposis the most common forms.Excluding hereditary forms,there is an important fraction of CRC cases that present familial aggregation for the disease with an unknown germline genetic cause.CRC can be also considered as a complex disease taking into account the common diseasecommom variant hypothesis with a polygenic model of inheritance where the genetic components of common complex diseases correspond mostly to variants of low/moderate effect.So far,30 common,low-penetrance susceptibility variants have been identified for CRC.Recently,new sequencing technologies including exomeand whole-genome sequencing have permitted to add a new approach to facilitate the identification of new genes responsible for human disease predisposition.By using whole-genome sequencing,germline mutations in the POLE and POLD1 genes have been found to be responsible for a new form of CRC genetic predisposition called polymerase proofreading-associated polyposis.

5-HTR2A Polymorphisms rs6311 and rs6313 and Major Depressive Disorder: A Meta-Analysis

rs6311 and rs6313 are two Single Nucleotide Polymorphisms (SNPs) on the Serotonin Receptor 2A gene (5-HTR2A) in complete linkage disequilibrium. Numerous gene association studies have examined the relationships between one or both of these two polymorphisms and Major Depressive Disorder (MDD), with conflicting results. The present meta-analysis examined 19 case-control gene association studies, 9 of which included rs6311 (n = 3382), and 15 of which included rs6313 (n = 5590). The strength of relationship with MDD was assessed by pooled odds ratios and 95% confidence intervals for both SNPs according to four genetic models. Heterogeneity was measured by Q and I2. Subgrouping was performed by minor allele and by ethnicity. Results were nonsignificant for all models and subgroups, suggesting that genotype alone does not play a major role in genetic susceptibility to depression. The potential for epistatic, epigenetic, and regulatory RNA interactions with these SNPs is discussed, and future areas of research are recommended.

ACE2 rs2074192位点多态性与非乙醇性脂肪性肝病易感性的相关性

目的探讨青岛地区人群血管紧张素转化酶2(ACE2)rs2074192位点多态性与非乙醇性脂肪性肝病(NAFLD)易感性的相关性。方法研究纳入NAFLD病人208例,健康查体者105例。收集受试者的血液标本,提取DNA,应用多聚酶链反应(PCR)检测ACE2基因rs2074192位点的基因型,比较ACE2 rs2074192位点基因型及等位基因频率在NAFLD组及对照组的分布差异。同时收集受试者的临床资料及实验室生化检查结果,比较不同基因型病人临床资料及实验室生化结果的差异。结果NAFLD组和对照组ACE2 rs2074192位点的基因型与等位基因分布差异均无统计学意义(P>0.05)。ACE2 rs2074192位点T等位基因女性携带者体质量指数高于未携带者,T等位基因男性携带者血清葡萄糖水平低于未携带者(t=-2.613、-3.195,P<0.05)。结论青岛地区人群ACE2 rs2074192位点多态性与NAFLD易感性无明显相关性。

DNA修复基因ERCC1多态性与肺癌易感性的关系

背景与目的最近研究发现DNA修复基因多态性可以影响到肿瘤的易感性,因此通过不同的DNA修复基因可筛选出肿瘤的易感人群,从而有望达到肿瘤的早期预防、诊断和治疗。本研究旨在分析DNA修复基因ERCC1多态性及其与肺癌易感性的关系。方法采用病例-对照研究,收集上海肺科医院原发性肺癌患者291例为病例组,同期住院的非肿瘤患者273例作为对照组,并进行流行病学调查。应用Taqman探针结合实时荧光PCR方法分析病例组和对照组的ERCC1基因T118C的多态性分布,比较不同基因型与肺癌易感性的关系,以及基因多态性与吸烟对肺癌的交互作用。结果在不吸烟人群中,ERCC1基因118位点3种基因型在病例组和对照组人群中分布差异有统计学意义(χ2=11.19,P<0.01)。在不吸烟人群中,与携带野生纯合基因型(C/C)相比,携带突变纯合基因型(T/T)者患肺癌的风险会增加,其校正OR值为3.16(95%CI:1.29-7.73,P<0.01)。以携带野生纯合基因型(C/C)且不吸烟者作为参照,吸烟>25包-年且携带野生纯合基因型(C/C)或杂合基因型(C/T)者患肺癌的风险均会提高,其校正OR值分别为2.62(95%CI:1.54-4.44)、2.41(95%CI:1.36-4.26,P<0.01)。以携带野生基因型者作为参照,携带突变纯合基因型者患腺癌的风险度会增加,其OR值为2.29(95%CI:1.05-4.78,P=0.03)。结论DNA修复基因ERCC1118C/T多态性可能对肺癌易感性产生影响,并可能与吸烟有一定的协同作用。

核苷酸切除修复系统基因遗传多态与晚期非小细胞肺癌患者铂类药物敏感性关系

背景与目的:肿瘤细胞对铂类药物的化疗敏感性与个体的DNA损伤修复能力关系密切,本研究探讨核苷酸切除修复系统(nucleotideexcisionrepair,NER)的重要成员XPC、XPD和ERCC1基因的遗传多态与晚期非小细胞肺癌(non-smallcelllungcancer,NSCLC)患者对铂类药物敏感性的关系。方法:对接受含铂类药物化疗的200例晚期NSCLC患者进行临床疗效评价。以聚合酶链-扩增片段长度多态性(PCR-AFLP)和限制性片段长度多态性(RFLP)的方法检测XPC-PAT、XPDLys751Gln(rs1052559)和ERCC1C8092A(rs1052559)多态的基因型,比较不同基因型与化疗敏感性的关系。结果:结合疗效情况,XPC-PAT遗传多态各基因型在化疗有效组(CR+PR)和无效组(SD+PD)中的分布频率差异有显著性(!2检验,P=0.023),携带XPCLL基因型个体的化疗敏感性是XPCSS基因型携带者的3.04倍(95%CI为1.25～7.41,P=0.015)。没有发现XPDLys751Gln和ERCC1C8092A多态与化疗敏感性的相关性。但联合分析后发现,核苷酸切除修复系统的这三个遗传多态在晚期NSCLC患者对铂类药物敏感性中存在一定的联合作用(趋势检验,P=0.021)。结论:核苷酸切除修复系统中XPC-PAT、XPDLys751Gln和ERCC1C8092A遗传多态可能与NSCLC患者对铂类药物敏感性相关。

代谢酶基因多态性与肺癌易感性关系的研究

目的 探讨代谢活化酶细胞色素P45 0 1A1(CYP1A1)、2D6(CYP2D6)、2E1(CYP2E1)和代谢解毒酶谷胱甘肽硫转移酶 (GSTM 1)基因多态性与肺癌易感性的关系及重度吸烟对肺癌易感性的影响。方法 采用PCR、PCR RFLP等技术检测 180例原发性肺癌患者及 2 2 4例肺部良性疾病患者和正常人 (对照组 )外周血代谢酶基因型。结果 CYP1A1突变等位基因 (m )、CYP2D6野生型等位基因 (w )、CYP2E1A基因型和GSTM 1功能缺失型 ( -)可使患肺癌的危险性增加到 1.5 0～ 1.5 8倍 (P <0 .0 5 )。携带GSTM 1( -)者若同时携带CYP1A1、2D6或 2E1中任意 1个易感基因型 ,可使患肺癌的危险性升高到 2 .2 4～ 2 .69倍 (P <0 .0 5 )。携带相同基因型者 ,重度吸烟比不吸烟者患肺癌的危险性显著升高。重度吸烟人群中携带 4种易感基因型者患肺癌的危险性显著增高 ,达 9.85倍 ( 95 %CI =2 .3 0～ 45 .71)。结论 代谢酶基因的易感等位基因携带者患肺癌的危险性上升 ,且与烟草致癌物暴露剂量呈正相关。

GSTM1和CYP2E1基因多态性与肺癌遗传易感性关系的研究

背景与目的 肺癌是中国人群恶性肿瘤死因的首位,其发病可能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P4502E1(CYP2E1)基因RsaⅠ/PstⅠ多态性和谷胱甘肽转 移酶M1(GSTM1)基因多态性与肺癌易感性之间是否存在相关性。方法 应用PCR RFLP和PCR法检测 99例人非小细胞肺癌患者和66例同期住院的肺良性疾病患者CYP2E1基因的RsaⅠ/PstⅠ多态性和 GSTM1基因多态性,并分析其与肺癌遗传易感性的相关性。结果 (1)CYP2E1基因RsaⅠ/PstⅠ多态性的 三种基因型在肺癌组和对照组的频率差异没有统计学意义(χ2=1.374,P=0.241)。(2)肺癌组GSTM1(-) 基因型频率显著高于对照组(分别为57.6%和40.9%)(χ2=4.401,P=0.036)。(3)携带GSTM1(-)基因型 的个体患肺癌的危险性显著高于GSTM1(+)基因型的个体(OR=1.96,95%CI=1.042～3.689,P= 0.037)。(4)与携带c1/c2或c2/c2基因型的不吸烟个体比较,携带c1/c1基因型的吸烟者患肺癌的风险显著 增加(OR=3.525,95%CI=1.168～10.638,P=0.025)。(5)联合分析CYP2E1基因RsaⅠ/PstⅠ多态性和 GSTM1基因多态性,携带有c1/c1和GSTM1(-)基因型的个体患肺癌的风险显著高于携带GSTM1(+)和 c1/c2或c2/c2基因型的个体(OR=3.

醇醛脱氢酶基因多态和饮酒习惯与肝癌易感性

目的研究乙醇脱氢酶2（ADH2）和乙醛脱氢酶2（ALDH2）基因多态及饮酒习惯与肝癌的易感性。方法对208例原发性肝癌和208例对照调查饮酒习惯,采用RCT-RFLR方法检测ADH2和ALDH2基因型。结果1）病例与对照ADH2和ALDH2基因型分布频率差异均无统计学意义。2）携带AL-DH2^1＊2或ALDH2^2＊2基因型且饮酒总量〉3kg年者,发生肝癌危险性是携带AL-DH211基因型不饮酒者的3.30倍（95%CI=1.24～8.83）;而携带ADH2^1＊2或ADH2^2＊2基因型者且饮酒总量〉3kg年与携带ADH211基因型不饮酒者相比,患肝癌危险性无显著增加。3）携带AL-DH2^1＊2或ALDH2^2＊2同时携带ADH2^1＊2或ADH2^2＊2基因型且饮酒总量〉3kg年者,与携带ALDH2^1＊1同时携带ADH2^1＊1基因型且饮酒总量≤3kg年者相比,患肝癌OR值虽有增加但未达显著性（OR=4.26,95%CI=0.63～29.08）。4）HBsAg阳性并携带ALDH2^1＊2或ALDH2^2＊2基因型且饮酒〉3kg年者,与HBsAg阴性并携带ALDH2^1＊1基因型且饮酒≤3kg年者相比,患肝癌危险升高49.71倍（95%CI=5.51～448.96）。结论大量饮酒和肝癌的关联与ALDH2基因有关,而与ADH2基因无关。

中国遗传高风险乳腺癌患者BRCA1/2编码区SNP突变频率及其与肿瘤临床病理特征相关研究

目的研究中国遗传高风险乳腺癌患者乳腺癌易感基因(BRCA)1/2编码区单核苷酸多态性(SNP)的突变频率,并探讨其相应位点多态性与肿瘤临床病理特征的关系。方法收集提取69例遗传高风险乳腺癌患者的外周血单个核细胞DNA,运用二代测序技术对BRCA1/2编码区的49个外显子序列进行检测分析。同时收集所有患者的临床病理资料,包括发病年龄、初潮年龄、首次妊娠年龄、肿瘤的TNM分期、免疫组化特征、是否为双侧乳腺癌及是否具有家族史等,分析BRCA1/2编码区相应位点多态性与肿瘤临床病理特征的相关性。结果研究共发现34个SNP位点,其中14个位于BRCA1,20个位于BRCA2;有高频位点18个及低频位点16个。BRCA1编码区rs80356892位点多态性与肿瘤临床病理特征存在相关性,该位点突变的患者倾向于双侧乳腺癌(P=0.005)、存在家族史(P=0.029)以及三阴性乳腺癌(P<0.001),且rs80356892位点突变与雌激素受体、孕激素受体表达呈负相关。结论BRCA1/2编码区SNP与乳腺癌发病风险及乳腺癌临床病理特征相关,因此SNP的检测将有助于发病风险的评估及遗传性乳腺癌的筛查、防治。

中国人细胞色素P450IA1基因变异与吸烟相关性肺癌的风险

目的：探讨多环芳烃类致癌物代谢酶细胞色素Ｐ４５０ＩＡ１ 基因（ＣＹＰ１Ａ１） 多型性与中国人肺癌易感性的关系。方法：应用ＰＣＲＲＦＬＰ 方法，分析１５０ 例原发性肺癌和３９１ 例正常对照者ＣＹＰ１Ａ１ 基因的ｍ １、ｍ２ 和ｍ ４ 位点突变。以比值比（ＯＲ） 及其９５ ％ 可信区限（ＣＩ） 比较不同基因型与肺癌风险的关系，以及与吸烟的交互作用。结果：位于３＇端ＭｓｐＩ识别的位点（ ｍ１） 和位于第７ 外显子ＢｓｒＤＩ 识别的位点（ｍ２） 具多态性，而位于第７ 外显子由ＢｓａＩ识别的位点（ｍ ４） 未见有变异。ｍ１ 变异型等位频率在对照组中为０－３６，而在肺癌病例组中为０－４６ 。携带至少一个变异基因拷贝者发生肺癌的风险比携带野生基因型者高２ 倍（ＯＲ ２－３ ；９５％ ＣＩ１－９～２－９） 。分层分析发现，肺鳞癌患者中ｍ １ 变异基因型频率更高（０－４８） ，携带此种基因型者发生肺鳞癌的相对风险（ＯＲ） 为３－０（９５％ ＣＩ２－２ ～４－０） 。ｍ２ 变异与ｍ１变异密切关联，符合率达７６ ％ 。携带至少一个ｍ ２ 变异基因拷贝者的ＯＲ 为１－９ （９５％ ＣＩ１－６ ～２－４） 。此外，ＣＹＰ１Ａ１ｍ１ 变异与吸烟有明显的交互作用。