胃癌hPOT1、hTERTSNP及蛋白表达与H.pylori感染和微卫星不稳的关系
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摘要
前言胃癌是我国最常见的恶性肿瘤之一,我国胃癌发病率也是全球最高的国家之一。胃癌的发生发展是一个多因素多阶段多基因参与的过程,其发生涉及到多种基因的异常改变,归因于环境与遗传因素相互作用的结果,其中幽门螺杆菌感染(Helicobacter pylori,Hp)是胃癌发生的主要危险因素,被WHO列为第一类致癌原。
     单核苷酸多态性(Single nucleotide polymorphisms,SNP)是指基因组中单个碱基的变异而导致的核苷酸序列多态性,是继微卫星之后的第3代遗传性标志。对SNPs数据库进行大范围评估结果显示,SNPs能够为研究多基因复杂疾病及个体间、不同群体或个体对肿瘤患病风险以及对药物反应的不同提供新的方法。已有对端粒相关基因(TERT、TERC、TERF1、TERF2、TINF2、TERF2IP、POT1和TNKS)共同的SNPs研究认为,这些变异对研究遗传相关疾病如癌症、再生障碍性贫血、自身免疫性疾病及染色体和端粒酶的异常都有重要意义。人端粒保护蛋白1(human protection of telomeres 1, hPOT1)基因是一种端粒单链DNA的结合蛋白,是端粒家族的成员之一,广泛存在于真核细胞中,被称为真核细胞看家基因。其主要作用是维护端粒的功能,调控端粒的长度,保护染色体的稳定。基因组不稳定伴随着端粒功能的异常,端粒功能异常可能促进胃癌的发生。hTERT( Human telomerase reverse transcriptase,hTERT)是端粒酶逆转录酶基因,是端粒酶的调节亚单位,依赖于端粒酶的活性而发挥调节端粒的作用,它能诱发细胞无限增殖及参与肿瘤发生,在肿瘤发生中起着至关重要的作用。端粒酶具有很高的肿瘤特异性,在85%-90%的肿瘤细胞中可以检测到端粒酶活性,而与肿瘤相邻的正常组织或良性病变几乎没有端粒酶活性。目的本研究检测了甘肃西部汉族人群胃癌hPOT1IVS13-98G/T及hTERT Ex2-
     659A/G位点单核苷酸多态性、hPOT1、hTERT蛋白表达、幽门螺杆菌感染和微卫星不稳,探讨hPOT1和hTERT基因单核苷酸多态性与胃癌患者发病风险的关系,并探讨以上二种基因与幽门螺杆菌感染和微卫星不稳的关系。
     方法168例胃癌患者来自于甘肃西部三家医院外科手术切除胃的患者,所有病例均经组织病理学确诊,术前未行放疗和化疗。取癌组织及手术切缘的正常组织(距癌5cm以上),立即置于-70℃的冰箱冻存备用。156例正常对照为同期在三家医院查体并行胃镜检查,在胃镜下均排除慢性胃炎、肠化、增生、溃疡和癌变。年龄性别与胃癌组匹配。两组均征得患者的同意,并签署知情同意书。胃癌临床分期按2003年国际抗癌联盟(UICC)TNM标准分期,组织病理按2000年WHO胃癌新的分类标准。全部检查对象均抽静脉血5ml,分离淋巴细胞,-70℃冰箱冻存备用。然后采用常规酚/氯仿/异戊醇抽取法提取DNA。采用聚合酶链反应和限制性片段长度多态性技术(PCR-RFLP)进行SNP基因型分析,采用聚合酶链反应和单链构象多态性技术(PCR-SSCP)检测微卫星不稳。取部分组织固定、石蜡包埋、组织切片HE染色病理证实,免疫组化检测蛋白表达,PCR检测尿素酶基因结合Warthin-Starry银染确诊幽门螺杆菌的感染。
     结果研究显示,胃癌组hPOT1IVS13-98 T/G位点TT、GG、GT基因型的频率分别为36.90%、41.67%、21.43%, T、G等位基因频率分别为57.74%、42.26%;对照组TT、GT、GG基因型的频率分别为24.36%、51.92%、23.72%,T、G等位基因频率分别为49.68%、50.32%。两组T、G等位基因型频率比较无显著性差异(χ2=3.5853,P= 0.0583)。以T/T基因型作为参照基因型,G/T和G/G两种基因型OR值分别为0.439(95%CI: 0.251-0.767,P=0.004)、0.514(95%CI: 0.264-0.999,P=0.050)。胃癌组hTERTEx2-659A/G位点GG、AG、AA型的频率分别为41.88%、47.5%、10.63%,G、A等位基因频率分别为65.62%、34.38%,对照组GG、AG、AA基因型的频率分别为28.29%、56.58%、15.13%,G、A等位基因的频率为56.58%、43.42%,两组G、A等位基因型频率比较有显著性差异(χ2=5.3734,P=0.0204)。以G/G基因型相比,A/G和A/A两种基因型OR值分别为0.519(95%CI:0.310-0.870,P=0.013)、0.550(95%CI: 0.255- 1.188,P=0.128)。
     hPOT1蛋白表达的阳性率在胃癌、异型增生、肠化生、正常胃粘膜分别为:91.33%、80.00%、55.00%、28.00%,在胃癌、异型增生、肠化生与正常胃粘膜组织相比差异有显著性( P<0.01)。hPOT1蛋白的表达在浸润较深、分化差的、Ⅲ/Ⅳ期胃癌中显著增高( P <0.05)。hTERT蛋白的阳性率在胃癌、异型增生、肠化生、正常胃粘膜分别为:76.67%、60.00%、25.00%、0.00%,胃癌中hTERT蛋白的表达与胃癌的浸润深度、淋巴结转移、胃癌分期相比差异无显著性(P>0.05),但在低分化胃癌表达的阳性率显著高于高中分化胃癌(P<0.05)。
     在胃癌、异型增生、肠化生、正常胃粘膜H.pylori的检出率分别为:54.00%、70.00%、55.00%、20.00%。在hPOT1IVS13-98 G/T三种基因型中,H.pylori检出率,GG型为51.52%,GT型为45.16%,TT型为65.45%,三型之间比较差异无统计学意义(χ2 =4.937,P=0.085),提示胃癌患者hPOT1IVS13-98G/T多态性与H.pylori感染无关;在hERTEx2-659A/G三种基因型中,AA型为66.67%,AG型为52.86%,GG型为50.88%,三型之间比较差异无统计学意义(χ2=1.215,P=0.545),提示胃癌组hERTEx2-659A/G多态性与H.pylori感染无关。H.pylori阳性患者中hPOT1蛋白的表达率为96.30%, H.pylori阴性患者中hPOT1蛋白的表达率为85.51%,二者之间比较有显著性差异(P<0.05)。H.pylori阳性患者中hTERT蛋白的表达率为85.19%, H.pylori阴性患者中hTERT蛋白的表达率为71.01%,二者之间比较有显著性差异(P<0.05)。
     对75例胃癌进行MSI检测,75例胃癌中两个位点MSI阳性29例,检出率为38.67%,其中BAT26位点MSI阳性率为12.00%;D5S346位点MSI阳性率为26.67%。MSI与患者年龄、性别、组织学类型及浸润深度无关(P>0.05),在无淋巴结转移及I、II期胃癌中检出率显著高于有淋巴结转移和III、IV期胃癌(P<0.05)。胃癌组hPOT1IVS13-98 G/T位点TT、GT、GG基因型在MSI组和MSS组中的频率比较差异无统计学意义(P>0.05)。hTERTEx2-659 A/G位点GG、AG、AA基因型在MSI组和MSS组中的频率比较差异无统计学意义(P>0.05)。H.pylori感染在MSI组和MSS组中的频率比较差异无统计学意义(P>0.05)。
     结论1.hPOT1IVS13-98 G/T及hTERTEx2-659A/G位点单核苷酸多态性可能与甘肃西部汉族人群的胃癌有关,为胃癌的保护因素。2. hPOT1表达水平随着胃癌恶性程度的增加而增加,检测胃癌中hPOT1蛋白的表达可判断胃癌的恶性程度及预后;3.hTERT表达水平随着胃癌恶性程度的增加而增加,检测胃癌中hTERT的表达可作为判断胃癌的恶性生物学行为的指标之一。4. H.pylori感染与hPOT1IVS13-98 G/T和hTERTEx2-659A/G单核苷酸多态性无关;H.pylori感染与hPOT1、hTERT蛋白表达密切相关,在hPOT1、hTERT阳性表达的患者H.pylori的感染率较高。5. MSI与hPOT1IVS13-98 G/T和hTERTEx2-659A/G单核苷酸多态性无关,与H.pylori感染也无关。
Gastric cancer(GC) is one of the most common malignant tumors in china, which is a multi-gene based disease caused by the interaction between enviromental and genetic factors. A large amount of epidemiological evidence has accumulated indicating a significant relationship between Helicobacterpylori (H.pylori,Hp) infection and gastric adenocarcinoma development. In 1994, the World Health Organization/International Agency for Research on Cancer concluded that Hp is a definite carcinogen based on the epidemiological findings.
     Single nucleotide polymorphisms(SNPs) is nucleotide sequent polymorphism caused by single-base mutation of genome that has been generally thought to be the third era mark of heredity following microsatellite. Vast investigation of the SNPs data has shown that it can provide us with new approaches to understand multi-gene involved diseases and to evaluate the inter-individual and inter-groups difference in tumor risks and treatment response.Through the common study of SNPs in seven genes of telomere (TERT,TERC, TERF1,TERF2,TINF2,TERF2IP,POT1 andTNKS), it can be presumed that these variants will be of significant meaning in study of gene-associated diseases as cancer, aplastic anemia,autoimmune diseases,and degenerative disorders,as well as chromosomal abnormalities and/or abnormal telomeres. Human protection of telomeres 1(hPOT1), a member of the telomeric family, is a telomeric single-strand DNA binding protein that widely exist in eucaryotic cell as a house-keeping gene. It plays an important role in regulating telomeric length, attendancing telomeric function and protecting chromosome stability. Telomeric disfunction is a common occurrence in genom instability, which may trigger the development of gastric cancer. Human telomerase reverse transcriptase (hTERT) is the catalytic subunit of human telomerase, which regulates the telomer length by taking part in telomerase activity. An average of over 85 percent of human malignant tumors has telomerase expression, which can induce the infinite generation of cells and participate in tumorigenesis. However, in normal adult cells and tissues, there is no telomerase activity or telomerase expression. Therefore, it draws increasingly attention at its role in tumorigenesis.
     In current study we investigated the SNPs of hPOT1IVS13-98G/T and hTERT Ex2-659A/G, the expression of hPOT1,hTERT protein and microsatellite instability, with the hope of understanding the correlation between GC risk and SNPs of hPOT1、hTERT.
     MATERIALS AND METHODS
     One hundred and sixty-eight cancer and corresponding normal tissues were obtained from surgically resected gastric carcinoma in three hospitals of west Gansu,China. A 5cm section was cut from each tissue and stained with hematoxylin/ eosin in order to ascertain whether the cancer cells in tissues were predominant or not. Normal mucosa was collected from local residents who come for regular health examining, exclused chronic gastritis, intestinal metaplasia, atypical hyperplasia, ulceration and canceration under gastroscopy. These samples were frozen immediately and stored at -70℃until analyzed.Age and sex of two groups has been matched and ethical approval has been informed consent. All carcinomas were staged according to UICC criteria and typed according to WHO 2000 criteria of histopathological classification. Genomic DNA was isolated by standard proteinase-K digestion and phenol-chloroform extraction protocols. SNPs were genotyped by PCR-restriction fragment length polymorphism (PCR-RFLP),microsatellite instability were detected by PCR-single strand conformation polymorphism (PCR-SSCP). The expression of hPOT1 and hTERT protein was detected by immunohistochemistry method. H.pylori infection was detected by PCR of urea enzyme gene of H.pylori and Warthin- Starry.
     RESULTS
     The frequencies of TT,GT and GG genotypes of hPOT1IVS13-98 G/T were 36.90%,41.67% and 21.43 % in patients with gastric cancer 24.36%, 51.92% and 23.72% in controls,respectively. The OR for any GT and GG genotype were 0.439 (95 %CI : 0.251-0.767,P=0.004) and 0.514(95%CI: 0.264-0.999,P=0.050) when compared with TT genotype, respectively. There were no significantly difference in genotype distribution and allele frequency of hPOT1IVS13-98 G/T polymorphism (χ2=3.5853,P= 0.0583). The frequencies of GG, AG and AA genotypes of hTERTEx2-659A/G were 41.88%, 47.5% and 10.63% in patients with gastric cancer and 28.29%, 56.58% and 15.13% in controls,respectively. The OR for any AG and AA genotype were 0.519 (95%CI:0.310-0.870, P=0.013), 0.550(95%CI: 0.255-1.188, P=0.128) when compared with GG genotype,respectively. There were significant difference in genotype distribution and allele frequency of hTERTEx2-659A/G polymorphism (χ2=5.3734, P=0.0204).
     The positive expression ratio of hPOT1 in neoplasms, gastric atypical hyperplasia, intestinal metaplasia, normal mucosa were respectively 91.33%, 80.00%, 55.00% and 28.00%, and hTERT positive expression rate were 76.67%, 55.00%, 25.00%, and 0.00% , respectttively.All the three parameters significantly increased in atypical hyperplasia, neoplasms and intestinal metaplasia compared to normal mucosa( P < 0.05). Expression of hPOT1 protein increased significantly inⅢ/Ⅳstaging gastric cancer with deep invading and bad differentiation (P <0.01), Expression of hTERT protein increased significantly in poorly differentiated group ( P <0.01). There were significant relationships among the two parameters in neoplasms and dysplasia,respectively(rGC=0.212,P =0.009;rDYS=0.504,P =0.023).
     The ratio of H.pylori infection in gastric cancer, atypical hyperplasia, intestinal metaplasia and normal mucosa were 54.00%,70.00%,55.00% and 20.00,% respectively. Among three genotypes of hPOT1IVS13-98G/T, the ratio of H.pylori infection were 51.52% in GG, 45.16% in GT and 65.45% in TT, with no difference among the three genotype (χ2= 4.937,P=0.085).It strongly implied that hPOT1IVS13-98 G/T polymorphism was not correlated with H.pylori infection in gastric cancer. Of the three genotype of hTERT Ex2- 659A/G, the ratio of H.pylori infection were 66.67% in AA, 52.86% in AG and 50.88% in GG, there were no significant difference among three genotype (χ2=1.215,P=0.545).This results suggested that hTERTEx2-659A/G polymorphism was not correlated with H.pylori infection in gastric cancer. The positive rate of hPOT1 protein in patients with H.pylori infection (96.30%) was significantly higher than that of patients with H.pylori infection negative (85.51%,P < 0.05).The positive ratio of hTERT protein of patients with H.pylori infection positive (85.19%) was significantly higher than that of patients with H.pylori infection negative (71.01%, P < 0.05) .
     Seventy-five cases of gastric carcinoma were studied for MSI by using two microsatellite markers. The positive ratio of MSI was detected in 29 of 75(38.67%) in two microsatellite markers, among which 9(12.00%) was detected at BAT26 locus and 20 (26.67%) was detected at D5S346 locus. MSI is not to related to sex, age,invading to serosa and histological type (P >0.05). However,the frequence of MSI in groups without lymph node metastasis and I and II staging is significantly higher than that of groups with lymph node metastasis and staging III and IV(P<0.01). MSI was not correlated with hPOT1 IVS13-98G/T and TERTEx2-659A/G polymorphism in gastric cancer; MSI was not correlated with H.pylori infection in gastric cancer.
     CONCUSION
     Our results indicate:①IVS13-98 G/TSNP of hPOT1 gene and Ex2-659A/GSNP of hTERT gene are probably associated with reduced risk for gastric carcinoma of west Gansu,China.②Expressions of hPOT1 and hTERT are up-regulated at an early stage of the gastric carcinonogenesis and they may play an important role in activity of telomerase. It may be useful to detect expression of hPOT1 and hTERT for predicting the biological behevor of gastric carcinoma.③H.pylori infection is not associated with IVS13-98 G/T SNP of hPOT1 and Ex2-659A/G SNP of hTERT, but associated with expression of hPOT1 and hTERT. There were no significant relationships between the IVS13-98G/TSNP and expression of hPOT1 in gastric carcinoma. There were no significant relationships between in gastric carcinoma.④MSI pathway is not related to hPOT1 IVS13-98 G/T, hTERTEx2- 659A/G polymorphism and H.pylori infection in gastric cancer.
引文
1.孙秀娣,牧人,周有尚.中国胃癌死亡率20年变化情况分析及其发展趋势预测中华肿瘤杂志,2004,26(1):4-9.
    2.党霞,玛尔哈巴,钟咏梅,等.慢性胃炎和胃溃疡幽门螺杆菌感染分析.中国医药导报,2006,3(27):40-41.
    3. Testim G. Gastric preneoplastic changes. Recenti Prog Med, 2004, 95(5): 239-244.
    4.林三仁,张莉.幽门螺杆菌与胃癌关系的研究进展.中华医学杂志,2004,84(14):1210-1211.
    5. KuniyasuH,KitadaiY,MienoH,et al.Helicobactorpylori infection is closely associated with telomere reductionin gastricumcosa.Oncology,2003,65(3):275-282.
    6. Matsumura S,One N,Kitadai Y, et al. A single nucleotide polymorphisms in the MMP-1 promoter is correlated with histological differentiation of gastric cancer . Cancer Res Clin Oncol,2004,130(5): 259-265.
    7. Kuraoka K, Matsumura S,Hamai Y, et al. A single nucleotide polymorphisms in the transmembrane domain coding region of HER-2 is associated with development and malignant phenotype of gastric cancer . In J Cancer ,2003,107(4): 593-596.
    8. Baumann P, Cech TR. POT1, the putative telomere end-binding protein in ission yeast and humans. Science,2001, 292(5519):1171–1175.
    9. Lei M, Podell ER, Cech TR. Structure of human POT1 bound to telomeric single-stranded DNA provides a model for chromosome end-protection. Nature Structural Molecular Biollogy ,2004,11(12):1223–1229.
    10. Nowak J, Januszkiewicz D, Lewandowski K, et al. Activity and expression of human telomerase in normal and malignant cells in gastric and colon cancer patients. Eur. J. Gastroenterol Hepatol, 2003,15(1): 75-80.
    11. Akay GG, Unal AE, Bayar S,et al. Telomerase activity could be used as a marker for neoplastic transformation in gastric adenocarcinoma: but it does not have a prognostic significance. Genet Mol Res, 2007,6(1): 41-49.
    12. Rossignol P, Collier S, Bush M, et al. Arabidopsis POT1A interacts with TERT-V(I8),an N-terminal splicing variant of telomerase.Journal of Cell Science,2007 120(20):3678-3687.
    13. Packer B R, Yeager M, Burdett L, et al. SNP500Cancer: a public resource for sequence validation, assay development, and frequency analysis for genetic variation in candidate genes .Nucleic Acids Research ,2006 ,34(Database Issue):D617-621
    14.萨姆布鲁克.D.W.拉塞尔著.分子克隆实验指南中译本.第3版(上册).北京:科学出版社,2002:463-471.
    15. Baumann P, Podell E, Cech TR, et al. Human POT1 (protection of telomeres) protein: cytolocalization, gene structure,and alternative splicing.Mol Cell Biol,2002,22(22): 8079- 8087.
    16. Bryce LA,Morrison N, Hoare SF, et al. Mapp ing of the gene for the human telomerase reverse transcrip tase, HTERT, to chromosome 5p15. 33 by fluorescence in situ hybridization.Neoplasia,2000,2 (3):197- 201.
    17. Tahara E. Genetic pathways of two types of gastric cancer. IARC-Sci-Publ,2004, 157: 327-349.
    18. Yamaguchi H, Calado RT, Ly H, et al. Mutations in TERT, the gene encoding the human telomerase reverse transcriptase, in aplastic anemia. N Engl J Med,2005, 352(14):1413-1424.
    19. Jiang R,Duan J,Windermuth A ,et al. Genome wide evaluation of the public SNP databases . Pharmacogenomics,2003,4(6): 779-789.
    20. Savage SA, Stewart BJ, Eckert A, et al Genetic variation, nucleotide diversity, and linkage disequilibrium in seven telomere stability genes suggest that these genes may be under constraint. Hum Mutat, 2005,26(4):343-350.
    21. Hsu CP, Hsu NY, Lee LW,et al. Ets2 binding site single nucleotide polymorphism at the hTERT gene promoter effect on telomerase expression and telomere length maintenance in non-small cell lung cancer. Eur J Cancer,2006, 42(10): 1466-1474.
    22. Matsubara Y, Murata M, Yoshida T, et al. Telomere length of normal leukocytes is affected by a functional polymorphism of hTERT. Biochem Biophys Res Commun, 2006,341(1):128-131.
    23. Savage SA,Chanock SJ,Lissowska J,et al.cancer.Genetic variation in five genes important in telomere biology and risk for breast cancer British Journal of Cancer, 2007, 97(6): 832-836.
    24. Kelleher C,Kurth I,Lnger J,et al.Human protection of telomeres1 (POT1) is anegative regulator of telomerase activity in vitro.J mol Cell Biol, 2005,25 (2):808-818
    25. Lei M, Zauge J, Podell ER, et al.Switching human telomerase on and off with hPOT1 protein in vitro.J Biol Chem,2005, 280 (21) : 20449-20456.
    26. Armbruster BN, Linardic CM,Veldman T,et al. Rescue of an hTERT mutant defective in telomere elongation by fusion with hPOT1.Molecular and Cell Biology, 2004,24(8): 3552-3561.
    27. Hockemeyer D, Sfeir AJ, Shay JW, et al. POT1 protects telomeres from a transient DNA damage response and determines how human chromosomes end. EMBO J, 2005, 24(14): 2667-2678.
    28. Surovtseva YV, Shakirov EV, Vespa L, et al.Arabidopsis POT1 associates with the telomerase RNP and is required for telomere maintenance.EMBO J, 2007, 26 (15): 3653-3661.
    29. Loayza D, Lange T. POT1 as a terminal transducer of TRF1 telomere length control. Nature, 2003,423(6943):1013-1018.
    30. Kondo T, Oue N, Yoshida K, et al.Expression of POT1 is associated with tumor stage and telomere length in gastric carcinoma. Cancer Res,2004, 64 (2):523-529.
    31. Yasui W,Oue N, Aung PP,et al. Molecular-pathological prognostic factors of gastriccancer: a review. Gastric Cancer, 2005,8(2): 86-94.
    32.帖君,房殿春,宁晓燕,等.人端粒保护蛋白在胃癌中的异常表达及其临床意义.胃肠病学和肝病学杂志,2006,15(1):2-14.
    33. Olaussen KA,Dubrana K,Domont J,et al.Telomeres and telomerase as targets for anticancer drug development.Crit Rev Oncol Hematol ,2006 ,57 (3) :191-214.
    34. Fujimoto R,Kamata N, Taki M, et al. Gene expression of telomerase related proteins in human normal oral and ectocervical epithelial cells. Oral Oncol,2003,39 (5) : 445 -452.
    35. Schneid ER,Stockr R, Boltze C,et al. Elevated telomerase activity, c- myc, and hTERT mRNA expression :association with tumour progression in malignant lipomatous tumours. J Pathol,2003,1999(4) :517-525.
    36. Wang S, Zhu J. Evidence for a relief of repression mechanism for activation of the human telomerase reverse transcriptase promoter.J Biol Chem,2003,278(21):18842 -18850.
    37. Brachner A,Sasgary S,Pirker C,et al. Telomerase- and alternative telomerelengthening-independent telomere stabilization in a metastasis-derived human non-small cell lung cancer cell line: effect of ectopic hTERT. Cancer Res, 2006, 66(7): 3584-3592.
    38.王国安,刘海峰,房殿春,等.胃粘膜端粒酶活化与细胞凋亡的关系.解放军医学杂志,2005,30(9):785-787.
    39.陈陵,陈婷,蔡永国,等.胃粘膜癌变过程中hTERT和相关基因表达的变化及其临床意义.胃肠病学和肝病学杂志,2006,15(5):443-447.
    40. Hoang-Vu C,Boltze C, Gimm O, et al. Expression of telomerase genes inthyroid carcinoma. Int J Oncol ,2002,21(2):265-272.
    41. Poremba C, Heine B, Diallo R, et al. Telomerase as a prognostic marker in breast cancer: high through put tissue microarray analysis of hTERT and hTR. J Pathol ,2002, 198(2):181-189.
    42. Grand CL, Han H, Munoz RM, et al. The cationic porphyrin TMPyP4 down-regulates c-MYC and human telomerase reversetrans criptase expression and inhibits tumor growth in vivo. Mol Cancer Ther, 2002,1(8):565-573.
    43. Sato N, Mizumoto K, Nagai E, et al. Telomerase as a new target for pancreatic cancer treatment. J Hepatobiliary Pancreat Surg,2002,9(3):322-327.
    44. de Lange T. Shelterin: the protein complex that shapes and safeguards human telomeres. Genes Dev, 2005, 19(18): 2100-2110.
    45. Armbruster BN, Linardic CM, Veldman T, et al. Rescue of an hTERT mutant defective in telomere elongation by fusion with hPot1. Mol Cell Biol, 2004,24(8): 3552-3561.
    46. Zaffaroni N, Villa R, Pastorino U,et al.Lack of telomerase activity in lung carcinoids is dependent on human telomerase reverse transcriptase transcription and alternative splicing and is associated with long telomeres. Clin Cancer Res, 2005,11(8): 2832-2839.
    47. Lei M, Zaug AJ, Podell ER,et al. Switching human telomerase on and off with hPOT1 protein in vitro. J Biol Chem, 2005, 280(21): 20449-20456.
    48. Salhab M,Jiang WG,Newbold RF,et al.The expression of gene transcripts of telomere-associated genes in human breast cancer: correlation with clinico-pathological parameters and clinical outcome.Breast Cancer Res Treat,2008,109(1):35-46.
    49. Yun-Lian T,Run-liang G,Bi-Hua D,et al.Detection and location of Helicobacter pylori inhuman ganstric carcinomas.World Gast roenterol,2005,11 (9) :1387-1391.
    50. Jorge O,Cuello Carrion FD, Jorge A, et al.Helicobacter pylori infection affects the expression of PCNA, p53, c-erbB22 and Bcl-2 in the human gastric mucosa. Rev Esp Enferm Dig,2003,95 (2) :89-104.
    51. Kubicka S, Claas C, Staab S.p53 mutation pattern and expression of c-erbB2 and c-met in gastric cancer: relation to histological subtypes, Helicobacter pylori infection and p rognosis.Dig Dis Sci, 2002, 47(1):114-121.
    52. Sugiyama T, Asaka M.Helicobacter pylori infection and gastric cancer.Med Electron Microsc,2004,37(3):149-157.
    53. Izzotti A, De Flora S, Cartiglia C,et al. Interplay between Helicobacter pylori and host gene polymorphisms in inducing oxidative DNA damage in the gastric mucosa. Carcinogenesis, 2007,28(4):892-898.
    54.韩俭,景涛,樊平,等.幽门螺杆菌感染和武威地区胃癌组织中核增殖抗原表达的关系.兰州医学院学报,2003,29(3):7-9.
    55. Jian-Hua Li, Xian-Zhe Shi, Shen Lv ,et al.Effect of Helicobacter pylori infection on p53 expression of gastric mucosa and adenocarcinoma with microsatellite instability. World J Gastroenterol ,2005 , 11 (28) : 4363-4366
    56.施宏,陈素玉,陈刚,等.幽门螺杆菌感染与胃癌浸润转移及相关因子表达的关系探讨.临床消化病杂志,2007,19(3):170-175.
    57.漆涌,伍勇,陶莹,等.幽门螺杆菌感染与胃部病变组织端粒酶活性相关性的研究.中国实验诊断学,2007,11(5):654-656
    58.孙燕,刘南植.幽门螺杆菌致胃癌上皮细胞凋亡的机制及其在胃癌发生中的作用.国外医学内科学分册,2004,31(10):419-433.
    59.房殿春.幽门螺杆菌致胃黏膜癌变的分子机制.解放军医学杂,2003,28(11):966-970.
    60. Wang S,zhu J.Evidence for a relief repression mechanism for activation of the human telomerase reverse transcriptase promoter.J Biol Chem,2003, 278 (21):18842-18850.
    61. Aida J, Shimomura N I, Nakamura K,et al. Telomere length variations in 6 mucosal cell types of gastric tissue observed using a novel quantitative fluorescence in situ hybridization method. Hum Pathol,2007,38(8):1192-1200.
    62.王国安,刘海峰,房殿春.胃癌前病变组织和胃癌中hTERT的表达及其与幽门螺杆菌感染的关系.第三军医大学学报,2004,26(19):1759-1761.
    63.陈威,袁媛.幽门螺杆菌感染与细胞因子单核苷酸多态性.世界华人消化杂志,2005,13(17):2108-2114.
    64. Garcia-Gonzalez MA,Lanas A, Quintero E,et al.Gastric cancer susceptibility is not linked to pro-and Anti-inflammatory cytokine gene polymorphisms in whites: a Nationwide Multicenter Study in Spain.American Journal of Gastroenterology, 2007, 102(9):1878-1892.
    65.王国安,刘海峰,房殿春,等.幽门螺杆菌感染对胃粘膜端粒酶活性的影响与细胞凋亡的关系.中华消化杂志,2006,26(6):421-422.
    66. Wong BC,Lam SK,Wong WM,et al. Helicobacter pylori eradication to prevent gastric cancer in a high-risk region of China: a randomized controlled trial. JAMA,2004,291(2):187-194
    67. Fang DC, Jass JR, Wang DX, et al. Infrequent loss of heterozygosity of APC/MCC and DCC genes in gastric cancer showing DNA microsatellite instability. J Clin Pathol 1999,52(7):504-508.
    68. Boland CR, Thibodeau SN, Hamilton SR, et al. A national cancer institute workshop on microsatellite instability for cancer detection and familial predisposition: development of international criteria for the determination of microsatellite instability in colorectal cancer. Cancer Res ,1998,58(22):5248–5257.
    69.陈国庭,朱正纲,尹浩然,等.胃癌微卫星不稳定性及其与临床病理生物学的关系.中华胃肠外科杂志,2004,7(3):225-228.
    70. Kim YH, Song SY, Kwon YD,et al.Microsatellite instable double primary cancers of the colorectum and stomach exhibit less favorable outcome.World J Gastroenterol , 2005, 11(26): 3998-4002.
    71.宋伟庆,周保军,陈怡,等.胃癌环氧化酶22、hML H1及hMSH2微卫星不稳定与基因调控的关系.肿瘤防治研究,2007,34(3):171-174.
    72.司佩任,房殿春,张浩,等.胃癌亚甲基四氢叶酸还原酶基因多态性及其与微卫星不稳的关系.中华流行病学杂志,2005,26(10):794-799.
    73.张道富,张小勇,刘平,等.胃癌、肠化生组织中TGF-βRⅡ、Bax基因突变与微卫星不稳定性.临床肿瘤学杂志,2006,11(2):133-141.
    74. Rugge M, Bersani G, Bertorelle R, et al.Microsatellite instability and gastric oninvasiveeneoplasia in a high risk population in Cesena, Italy. J Clin Pathol,2005, 58(8):805-810
    75. Gazvoda B, Juvan R, Zupanic-Pajnic I,et al.Genetic changes in Slovenian patients with gastric adenocarcinoma evaluated in terms of microsatellite DNA. Eur J Gastroenterol Hepatol, 2007 ,19(12):1082-1089.
    76. Beghelli S, Manzoni G, Barbi S, et al.Microsatellite instability in gastric cancer is associated with better prognosis in only stage II cancers. Surgery,2006 , 139(3): 347-356.
    77. Lenug WK,Kim JJ,kim JG,et al. microsatellite instability in gastric intestinal etaplasia in patients with and without gastric cancer.Am J Pathol, 2000, 156: 537-543
    78. Gologan A,Sepulveda AR.Microsatellite instability and DNA mismatch repair deficiency testing inhereditary and sporadic gastrointestinal cancers. Clin Lab Med,2005,25(1):179-196.
    79. Choe WH,Lee SY,Lee JH,et al.High frequency of microsatellite instability in intestinal -type gastric cancer in Korean patients. Korean J Intern Med,2005,20(2):116-22.
    80. Landen CN,Klingelhutz A,Coffin JE,et al.Genomic instability is associated with lack of telomerase activation in ovarian cancer. Cancer Biol Ther,2004,3(12):1250-1253.
    1. Baumann P, Cech TR. Pot1, the putative telomere end-binding protein in fission yeast and humans. Science, 2001, 292(5519): 1171-1175.
    2. Baumann P, Podell E, Cech TR. Human Pot1 (protection of telomeres) protein: cytolocalization, gene structure, and alternative splicing. Mol Cell Biol, 2002, 22(22): 8079-8087.
    3. Loayza D, Parsons H, Donigian J,et al. DNA binding features of human POT1: a nonamer 5’-TAGGGTTAG-3’minimal binding site, sequence specificity, and internal binding to multimeric sites. J Biol Chem, 2004, 279(13): 13241-13248.
    4. Ye JZ, Hockemeyer D, Krutchinsky AN, et al. POT1-interacting protein PIP1: a telomere length regulator that recruits POT1 to the TIN2/TRF1 complex. Genes Dev, 2004, 18(14): 1649-1654.
    5. Liu D,Safari A,Connor MS,et al. PTOP interacts with POT1 and regulates its localization to telomeres. Nat Cell Biol, 2004, 6(7): 673-680.
    6. Colgin LM, Baran K, Baumann P, et al. Human POT1 facilitates telomere elongation by telomerase. Curr Biol, 2003, 13(11): 942-946.
    7. Veldman T, Etheridge KT, Counter CM. Loss of hPot1 function leads to telomere instability and a cut-like phenotype. Curr Biol, 2004, 14(24): 2264-2270.
    8. Yang Q, Zheng YL, Harris CC. POT1 and TRF2 cooperate to maintain telomeric integrity. Mol Cell Biol, 2005, 25(3): 1070-1080.
    9. de Lange T. Shelterin: the protein complex that shapes and safeguards human telomeres. Genes Dev, 2005, 19(18): 2100-2110.
    10. Loayza D, De Lange T. POT1 as a terminal transducer of TRF1 telomere length control. Nature, 2003, 423 (6943): 1013-1018.
    11. Lei M, Zaug AJ, Podell ER,et al. Switching human telomerase on and off with hPOT1 protein in vitro. J Biol Chem, 2005, 280(21): 20449-20456.
    12. Savage SA, Stewart BJ, Eckert A, et al. Genetic variation, nucleotide diversity, and linkage disequilibrium in seven telomere stability genes suggest that these genes may be under constraint. Hum Mutat, 2005, 26(4): 343-350.
    13. Hockemeyer D, Sfeir AJ, Shay JW,et al. POT1 protects telomeres from a transient DNAdamage response and determines how human chromosomes end. EMBO J, 2005, 24(14): 2667-2678.
    14. Opresko PL, Mason PA, Podell ER,et al. POT1 stimulates RecQ helicases WRN and BLM to unwind telomeric DNA substrates. J Biol Chem, 2005, 280(37): 32069- 32080.
    15. Armbruster BN, Linardic CM, Veldman T, et al. Rescue of an hTERT mutant defective in telomere elongation by fusion with hPot1. Mol Cell Biol, 2004, 24(8): 3552-3561.
    16. Zaffaroni N, Villa R, Pastorino U,et al. Lack of telomerase activity in lung carcinoids is dependent on human telomerase reverse transcriptase transcription and alternative splicing and is associated with long telomeres. Clin Cancer Res, 2005, 11(8): 2832-2839.
    17. Kondo T, Oue N, Yoshida K, et al. Expression of POT1 is associated with tumor stage and telomere length in gastric carcinoma. Cancer Res, 2004, 64(2): 523-529.
    18. Montgomery E, Wilentz RE, Argani P,et al. Analysis of anaphase figures in routine histologic sections distinguishes chromosomally unstable from chromosomally stable malignancies. Cancer Biol Ther, 2003, 2(3): 248-252.
    19. Gisselsson D, Jonson T, Petersen A, et al. Telomere dysfunction triggers extensive DNA fragmentation and evolution of complex chromosome abnormalities in human malignant tumors. Proc Natl Acad Sci U S A, 2001, 98(22): 12683-12688.
    20. Kelleher C, Kurth I, Lingner J. Human protection of telomeres 1 (POT1) is a negative regulator of telomerase activity in vitro. Mol Cell Biol, 2005, 25(2): 808-818.
    21.帖君,房殿春,宁晓燕,等.人端粒保护蛋白在胃癌中的异常表达及其临床意义.胃肠病学和肝病学杂志, 2006, 15:12-14.
    22. Maser RS, DePinho RA. Connecting chromosomes, crisis, and cancer. Science, 2002, 297(5581): 565-569.
    23. Gordon KE, Ireland H, Roberts M, et al. High levels of telomere dysfunction bestow a selective disadvantage during the progression of human oral squamous cell carcinoma. Cancer Res, 2003, 63(2): 458-467.
    24. Heek NT, Meeker AK, Kern SE, et al. Telomere shortening is nearly universal in pancreatic intraepithelial neoplasia. Am J Pathol, 2002, 161(5): 1541-1547.
    25. Jiang R, Duan J, Windemuth A, et al. Genome-wide evaluation of the public SNP databases. Pharmacogenomics, 2003, 4(6): 779-789.
    1. Werner M, Becker KF, Hofler H.Gastric adenocarcinoma: pathomorphology and molecular pathology.Cancer Res Clin Oncol ,2001,127(4):207-216.
    2. Yasui W, Oue N, Kuniyasu H ,et al. Molecular diagnosis of gastric cancer: present and future. Gastric Cancer,2001,4(3):113-121.
    3. Feakins RM, Nickols CD, Bidd H, et al. Abnormal expression of pRb, p16, and cyclin D1 in gastric adenocarcinoma and its lymph node metastases: relationship with pathological features and survival. Hum Pathol, 2003,34(12):1276-1282.
    4. Fondevila C, Metges JP, Fuster J, et al. p53 and VEGF expression are independent predictors of tumor recurrence and survival following curative resection of gastric cancer. Br J Cancer, 2004,90(1):206-2015.
    5. Pinto-de-Sousa J, Silva F, David L, et al. Clinicopathological significance and survival influence of p53 protein expression in gastric carcinoma. Histopathology, 2004,44(4) :323-331.
    6. Al-Moundhri MS,Nirmala V,Al-Hadabi I ,et al .The prognostic significance of p53, p27 kip1, p21 waf1, HER-2/neu, and Ki67 proteins expression in gastric cancer: a clinicopathological and immunohistochemical study of 121 Arab patients. Surg Oncol,2005 ,91(4):243-252.
    7. Koo SH, Jeong TE, Kang J, et al. Prognostic implications for gastric carcinoma based on loss of heterozygosity genotypes correlation with clinicopathologic variables. Cancer Genet Cytogenet,2004,153(1): 26-31.
    8. Takahashi H, Endo T, Yamashita K, et al. Mucin phenotype and microsatellite instability in early multiple gastric cancers. Int J Cancer ,2002,100(4):419-424.
    9. Onitsuka K,Shibao K,Nakayama Y,et al. Prognostic significance of UDP-N–acetyl -alpha-D-galactosamine:polypeptide N-acetylgalac-to-saminy ltransferase– (GalNAC-T3) expression in patients with gastric carcinoma. Cancer Sci, 2003, 94 (1) :32-36.
    10. Kondo T,Oue N,Yoshida K, et al. Expression of POT1 is associated with tumor stage and telomere length in gastric carcinoma. Cancer Res ,2004,64(2):523-529.
    11. Yasui W,Oue N,Aunget PP, et al .Molecular-pathological prognostic factors of gastric cancer: a review References. Gastric Cancer,2005,8(2):86-94.
    12. Shimada Y, Yamasaki S, Hashimoto Y, et al. Clinical significance of dysadherin expression in gastric cancer patients. Clin Cancer Res, 2004,10(8):2818-2823.
    13. Chan AO, Lam SK, Chu KM,et al. Soluble E-cadherin is a valid prognostic marker in gastric carcinoma.Gut ,2001,48(6):808-811.
    14. Mitani Y, Oue N, Hamai Y, et al. Histone H3 acetylation is associated with reduced p21WAF1/CIP1 expression in gastric carcinoma. J Pathol ,2005,205(1):65-73.
    15. Yasui W, Oue N, Ono S, et al. Histone acetylation and gastrointestinal carcinogenesis . Ann NY Acad Sci ,2003,983(3):220-231.
    16. Gonzalez CA, Sala N, Capella G. Genetic susceptibility and gastric cancer risk . Int J Cancer ,2002,100(3):249-260.
    17. Kuraoka K, Oue N, Matsumura S, et al. A single nucleotide polymorphism in the transmembrane domain coding region of HER-2 is associated with development and malignant phenotype of gastric cancer. Int J Cancer ,2003,107(4):593-596.
    18. Hamai Y, Matsumura S, Kuraoka K, et al. A single nucleotide polymorphism in the untranslated region of EGF gene is associated with occurrence and malignant progression of gastric cancer. Pathobiology ,2005,72(3):133-138.
    19. Kuraoka K, Oue N, Yokozaki H, et al. Correlation of a single nucleotide polymorphism in the Ecadherin gene promoter with tumorigenesis and progression of gastric carcinoma in Japan. Int J Oncol ,2003,23(2):421-427.
    20. Matsumura S, Oue N, Kitadai Y, et al. A single nucleotide polymorphism in the MMP-1 promoter is correlated with histological differentiation of gastric cancer. J Cancer Res Clin Oncol, 2004,130(5):259-65.
    21. Matsumura S, Oue N, Nakayama H, et al. A single nucleotide polymorphism of the MMP9 promoter affects tumor progression and invasive phenotype of gastric cancer. J Cancer Res Clin Oncol ,2005, 131(1):19-25.
    22. Yasui W, Oue N, Ito R, et al. Search for new biomarkers of gastric cancer through serial analysis of gene expression and its clinical implications. Cancer Sci , 2004, 95(5):385-392.
    23. El-Rifai W, Moskaluk CA, Abdrabbo MK, et al. Gastric cancers overexpress S100Acalciumbinding proteins. Cancer Res ,2002,62(23):6823-6826.
    24. Oien KA, Vass JK, Downie I,et al. Profiling, comparison and validation of gene expression in gastric carcinoma and normal stomach. Oncogene,2003,22 (27) : 4287-4300.
    25. Lee JY, Eom EM, Kim DS, et al. Analysis of gene expression profiles of gastric normal and cancer tissues by SAGE. Genomics,2003,82(1):78-85.
    26. Oue N, Hamai Y, Mitani Y, et al. Gene expression profile of gastric carcinoma; identification of genes and tags potentially involved in invasion, metastasis, and carcinogenesis by serial analysis of gene expression. Cancer Res,2004,64 (7): 2397-2405.
    27. Poser I, Tatzel J, Kuphal S, et al. Functional role of MIA in melanocytes and early development of melanoma. Oncogene,2004,23(36):6115-6124.
    28. Hippo Y, Taniguchi H, Tsutsumi S, et al. Global gene expression analysis of gastric cancer by oligonucleotide microarrays. Cancer Res,2002,62(1):233-240.
    29. Inoue H, Matsuyama A, Mimori K, et al. Prognostic score of gastric cancer determined by cDNA microarray. Clin Cancer Res,2002,8(11):3475-3479.
    30. Weiss MM, Kuipers EJ, Postma C, et al. Genomic alterations in primary gastric adenocarcinomas correlate with clinicopathological characteristics and survival. Cell Oncol,2004,26 (5-6):307-317.
    1. Baumann P, Cech TR. POT1, the putative telomere end-binding protein in ission yeast and humans. Science,2001, 292(5519): 1171–1175.
    2. Packer B R, Yeager M, Burdett L, et al. SNP500Cancer: a public resource for sequence validation, assay development, and frequency analysis for genetic variation in candidate genes Nucleic Acids Research 2006,34(Database Issue):D617-D621
    3. Baumann P, Podell E,Cech TR,et al. Human POT1 (protection of telomeres) protein: cytolocalization, gene structure, and alternative splicing.Mol Cell Biol, 2002, 22 (22):8079-8087.
    4. Jiang R,Duan J,Windermuth A ,et al. Genome wide evaluation of the public SNP databases. Pharmacogenomics, 2003, 4(6): 779–789.
    5. Savage SA, Stewart BJ, Eckert A, et al Genetic variation, nucleotide diversity, and linkage disequilibrium in seven telomere stability genes suggest that these genes may be under constraint. Hum Mutat, 2005, 26 (4):3-350.
    6. Savage SA, Chanock SJ, Lissowska J, et al.Genetic variation in five genes important in telomere biology and risk for breast cancer .British Journal of Cancer,2007, 97(6):2– 836.
    7. Majevski J, Ott J.Distribution and characterization of regulatory elements in the human genome. Genome Res, 2002, 12(12):1827–1836.
    8. Kondo T, Oue N, Yoshida K, et al .Expression of POT1 is associated with tumor stage and telomere length in gastric carcinoma. Cancer Res,2004,64 (2):523-529.
    9. Yasui W, Oue N, Aung PP,et al. Molecular-pathological prognostic factors of gastric cancer: a review. Gastric Cancer, 2005, (2): 86–94.
    10. Salhab M,Jiang WG,Newbold R F,et al.The expression of gene transcripts of telomere-associated genes in human breast cancer: correlation with clinico-pathological parameters and clinical outcome[J] . Breast Cancer Res Treat, 2008,109(1):35-46.
    11. Rossignol P, Collier S, Bush M, et al. Arabidopsis POT1A interacts with TERT-V(I8),an N-terminal splicing variant of telomerase.Journal of Cell Science ,2007,120(20):3678-3687

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