砷剂对皮肤角质形成细胞P53功能的影响及其机制研究
详细信息    本馆镜像全文|  推荐本文 |  |   获取CNKI官网全文
摘要
流行病学研究表明低浓度砷剂的暴露与皮肤癌等各种肿瘤的发生有关。砷剂虽然被公认为是人类的致癌剂之一,但是其致癌作用机制仍存在争论。有的学者认为砷剂可单独引起肿瘤的发生,而有的学者认为砷剂只是协同其它致癌物导致正常细胞的恶性转化。p53基因是已知的抑癌基因之一,其介导的信号传导途径在细胞的增殖分化、应激和癌变等生命过程中起着极其重要的作用,被称为“基因组卫士”。鼠双微粒体2(murine double minute2,MDM2)基因是p53的下游基因之一,p53可激活MDM2转录,MDM2反过来又抑制p53的功能,二者形成自动调节反馈环,以保持正常情况下p53处于低水平状态。正确的亚细胞定位对于p53的功能活性十分重要,p53被激活后进入胞核内,激活其靶基因的转录,之后回到胞浆中被降解。MDM2由于具有核输出序列(NES)和核定位序列(NLS)而具有核浆穿梭能力,NES使MDM2由胞核到胞浆而NLS使之由胞浆到胞核。MDM2蛋白可把p53/MDM2复合物直接运出细胞核,MDM2的核浆穿梭能力对其抑制p53的功能活性非常重要。本课题研究中,我们以hTERT永生化的皮肤角质形成细胞为研究对象,探讨了砷剂对皮肤角质形成细胞p53功能的影响及MDM2在其中所起的作用机制,为阐明砷剂引起皮肤癌的机理提供新的实验依据。
     第一章低浓度砷剂经由上调MDM2介导p53胞浆分布所致功能失活
     目的:探讨低浓度砷剂对人皮肤角质形成细胞中MDM2蛋白的影响及其与p53的亚细胞分布状态和功能的关系。
     方法:以hTERT永生化的皮肤角质形成细胞为研究对象。采用蛋白印迹法(Western blotting)研究0.5μmol/L、1μmol/L和2μmol/L亚砷酸钠处理12小时和24小时后MDM2、p53和丝氨酸15位磷酸化的p53蛋白的表达水平,并且与5-Fu和紫外线处理作比较。采用细胞免疫荧光染色法研究砷剂处理前后p53蛋白的亚细胞定位及细霉素B和Nutlin-3预处理对其影响。
     结果:低浓度砷剂上调了角质形成细胞中MDM2蛋白的表达,但对p53蛋白表达无明显影响。随着低浓度砷剂剂量的逐渐增加,MDM2蛋白的表达水平亦逐渐增加;随着砷剂作用时间的逐渐增加,MDM2蛋白的表达水平也逐渐增强。低浓度砷剂处理后角质形成细胞p53蛋白主要分布在胞浆。细霉素B和Nutlin-3预处理可以阻断砷剂诱导的p53胞浆分布。先用低浓度砷剂处理角质形成细胞后再加5-Fu刺激,此时5-Fu激活p53功能受到明显的抑制。
     结论:低浓度砷剂呈剂量和时间依赖性上调角质形成细胞中MDM2蛋白的表达;低浓度砷剂可经由上调MDM2蛋白表达介导p53的胞浆分布;低浓度砷剂诱导的p53胞浆分布导致p53功能性失活。
     第二章低浓度砷剂上调MDM2的机制探讨
     目的:探讨低浓度砷剂上调MDM2表达的作用机制。
     方法:构建pGL3-MDM2基因启动子报告基因表达载体,采用荧光素酶报告基因分析方法观察亚砷酸钠对MDM2基因P1、P2启动子转录活性的影响。应用1μmol/L和2μmol/L亚砷酸钠处理皮肤角质形成细胞24h后采用逆转录-聚合酶链反应(RT-PCR)方法检测MDM2 mRNA的表达水平。应用PD98059、SB203580和LY294002等特异性信号转导通路抑制剂预处理后再观察砷剂对角质形成细胞MDM2表达的影响。
     结果:低浓度砷剂可显著诱导MDM2基因P1启动子的荧光素酶活性(P<0.05)。随着低浓度砷剂的剂量逐渐增加,MDM2 mRNA的表达水平逐渐增高。PD98059预处理可完全阻断砷剂上调角质形成细胞中MDM2的表达,而SB203580和LY294002预处理对砷剂诱导的MDM2表达上调无明显影响。
     结论:通过MAPK/ERK信号转导通路,低浓度砷剂激活MDM2基因P1启动子的转录活性,从而诱导MDM2的表达。
     第三章低浓度砷剂通过功能性失活p53发挥辅助致癌作用
     目的:探讨低浓度砷剂对紫外线引起角质形成细胞凋亡的影响及其与砷性皮肤癌作用机制的关系。
     方法:应用0.5μmol/L和1μmol/L亚砷酸钠处理角质形成细胞24h后,再用40mJ/cm~2紫外线照射。采用流式细胞术和Hoechst33258胞核染色检测砷剂和UV引起的细胞凋亡。
     结果:0.5μmol/L和1μmol/L砷剂处理角质形成细胞后凋亡率分别为1.2%和1.5%,与正常对照组1.5%无显著性差异(P>0.05)。而先经过0.5μmol/L和1μmol/L砷剂预处理后的角质形成细胞再照射紫外线,此时凋亡率分别为48.8%和39.9%,与未经砷剂预处理直接照射UV组凋亡率64.7%相比有显著性差异(P<0.05)。表明砷剂预处理可导致角质形成细胞对UV的凋亡抗性。Hoechst33258核染色结果与之相一致。
     结论:低浓度砷剂暴露可损害皮肤角质形成细胞对紫外线引起的凋亡反应;低浓度砷剂可通过功能性失活p53从而发挥其辅助致癌作用。
It has been proved by epidemiology that exposure of low concentration arsenic is associated with risk of cancers such as skin cancer.Although arsenic carcinogenesis is well documented,the mechanism of action is still debated.Some scientists intsist that arsenic can induce carcinogenesis by itself.Others hold that arsenic is only a co-carcinogen.
     P53 gene is one of the well-known antioncogenes.The signal trasnduction pathway mediated by p53 play the most importmant role in the cellular proliferation,differentiation,stress and carcinogenesis.P53 gene is named as "guardian of genome".MDM2(murine double minute 2, MDM2)gene is one of the downstream genes of p53.p53 can stimulate the transcription of MDM2 gene while MDM2 can inhibit the function of p53.So p53 and MDM2 form an autoregulated feed-back loop which keep p53 at low activity under normal condition.
     Accurate sub-cellular location is very important to p53 function. After activated,p53 go to nucleus and activate the transcription of target genes.Then p53 is degradated at cytoplasm.MDM2 protein can shuttle back and forth beween nucleus and cytoplasm due to its NES and NLS. NES can pull MDM2 protein from nucleus to cytoplasm while NLS can pull MDM2 protein from cytoplasm to nucleus.MDM2 protein can transport p53 /MDM2 complex between nucleus and cytoplasm.The ability of shuttling back and forth is very important for MDM2 to inhibit the function of p53.In our experment,the hTERT immortalized human keratinocytes were used to explore the effects of arsenic on p53 and MDM2.It will provide novel research findings to clarify arsenic carcinogenesis in the skin.
     The first chapter Low concentration arsenic functional inactivated p53 by cytoplasmic distribution through upregulation of MDM2
     Objective:To explore the effects of low concentration arsenic on MDM2 protein and association with p53 subcellular location and function in human keratinocytes.
     Methods:hTERT immmortalized human keratinocyte were used as model.Western blotting was used to explore the protein levels of MDM2, p53 and p53 phosphorylation at serine 15 site.After treatment of 0.5μmol/L,1μmol/L and 2μmol/L sodium arsenite for 12 hours or 24 hours.Immunofluorescence staining was used to observe the subcellular location of p53 protein before and after arsenic treatment and the effects of LMB and Nutlin-3.
     Results:The protein level of MDM2 was upregulated after low concentration arsenic administration while p53 protein has no obvious change.MDM2 protein increased steadily with the increase of dose and duration of arsenic treatment.Most of p53 protein located at cytoplasm in the keratinocyte after arsenic treatment.LMB and Nutlin-3 can block arsenic-induced p53 cytoplasmic distribution.Pretreatment of arsenic on keratinocyte can interfere with 5Fu-induced p53 activation.
     Conclusion:Low concentration arsenic upregulate MDM2 protein in a dose and time dependent manner.Low concentration arsenic induce p53 cytoplasmic distribution through upregulation of MDM2.Low dose arsenic-induced p53 cytoplasmic distribution functionally inactivated p53.
     The second chapter Mechanism of low concentration arsenic-induced upregulation of MDM2
     Objective:To explore the mechanism of action of upregulation of MDM2 protein after low dose arsenic treatment.
     Methods:The luciferase report gene system was used to observe the effects of sodium arsenite on MDM2 gene P_1、P_2 promoter.RT-PCR was used to explore the mRNA level of MDM2 after 1μmol/L and 2μmol/L sodium arsenite treatment in keratinocytes for 24 hours.Pretreatment of PD98059,SB203580 and LY294002 was used to interfere with the effects of sodium arsenite on MDM2 protein expression in keratinocytes.
     Results-The luciferase activity of MDM2 P_1 promoter was induced obviously after low concentration arsenic treatment(p<0.05).MDM2 mRNA level increased steadily with the increase of sodium arsenic. Pretreatment of PD98059 can totally block arsenic-induced MDM2 upregulation while SB203580 and LY294002 have no effect.
     Conclusion:Through MAPK/ERK pathway,low dose aresnic can induce the transciptional activity of P_1 promoter of MDM2 gene promoter, and then upregulate the expression of MDM2.
     The third chapter low concentration arsenic acts as a co-carcinogen by functional inactivation of p53
     Objective:To explore the effect of low dose arsenic on UV-induced apoptosis of keratinocyte and association with arsenic carcinogenesis in the skin.
     Methods:Flow cytometry was used to measure UV-induced apoptosis after 0.5μmol/L and 1μmol/L sodium arsenite treatment for 24 hours in keratinocytes.
     Results:The apoptotic rate of 0.5μmol/L and 1μmol/L sodium arsenite was 1.2%and 1.5%.There is no difference compared to 1.5%of control(P>0.05).After pretreated by 0.5μmol/L and 1μmol/L sodium arsenite,UV-induced apoptotic rate was 48.8%and 39.9%.There is significant difference compared to 64.7%of control(P<0.05).The results of Hoechst nuclei staining is the same as flow cytometry.
     Conclusion:Low dose arsenic exposure interfered with UVinduced apoptosis in keratinocytes.Low concentration of arsenic acts as a co-carcinogen by functional inactivation of p53.
引文
[1] Jones FT. Abroad view of arsenic[J]. Poult Sci, 2007,86(1):2-14.
    [2] Wang CH, Hsiao CK, Chen GL, et al. A review of the epidemiologic literature on the role of environmental arsenic exposure and cardiovascular diseases[J]. Toxicol Appl Pharmecol, 2007,222(3):344-350.
    [3] Sun G, Li X, Pi J,et al. Current research problems of chronic arsenicosis in China[J]. J Health Popul Nutr, 2006,24(2):176-181.
    [4] Rossman TG. Mechanism of arsenic carcinogenesis: an integrated approach[J]. Mutation Research, 2003,533:37-65
    [5] Chen CJ, Wang SL, Chiou JM, et al. Arsenic and diabetes and hypertension in human populations: a review[J]. Toxicol Appl Pharmacol, 2007,222(3):298-304
    [6] Tseng GH, Tai TY, Chong CK, et al. Long-term arsenic exposure and incidence of noninsulin dependent diabetes mellitus: A cohort study in arsenicosis hyperendemic villages in Taiwan[J]. Environ Health Perspect, 2000,108: 847 -851.
    [7] Tondel M, Rahmen M, Magnuson A, et al. The relationship of arsenic levels in drinking water and the prevalence rate of skin lesions in Bangladesh [J]. Environ Health Perspect, 1999,107:727-729.
    [8] Bourdon JC. P53 and its isoforms in cancer[J]. Br J Cancer, 2007,97(3): 277-282.
    [9] Stiewe T. The p53 family in differentiation and tumorigenesis[J]. Nat Rev Cancer, 2007,7(3): 165-168.
    [10] Efeyan A, Serrano M. P53: guardian of the genome and policeman of the oncogenes[J]. Cell Cycle, 2007,6(9): 1006-1010.
    [11] Murray JK, Gellman SH. Targeting protein-protein interactions: lessons from p53/MDM2[J]. Biopolymers, 2007,88(5):657-686.
    [12] Bose I, Ghosh B. The p53-MDM2 network: from oscillations to apoptosis[J]. J Biosci, 2007,32(5):991-997.
    [13] Haupt Y, Maya R, Kazaz A, et al. MDM2 promotes the rapid degradation of p53[J]. Nature, 1997,387(6630):296-299.
    [14] Schon 0, Friedler A, Bycroft M, et al. Molecular mechanism of the interaction between MDM2 and p53 [J]. J Mol Biol, 2002,323(3):491-501.
    [15] Hughes MF, Kenyon EM, Kitchim KT. Understanding arsenic carcinogenicity by the use of animal models[J]. Toxicol Appl Pharmacol, 2004,198(3):336-376.
    [16] Anetor JI, Wanibuchi H, Fukushima S. Arsenic exposure and its health effects and risk of cancer in developing countries: micronutrients as host defence[J]. Asian Pac J Cancer Prev, 2007,8(1): 13-23.
    [17] Rahman M. International research on arsenic contamination and health[J]. J Health Popul Nutr, 2006,142-163.
    [18] Pott WA, Benjamin SA, Yang RS. Pharmacokinetics, metabolism, and carcinogenicity of arsenic[J]. Rev Environ Contam Toxicol, 2001,169:165-214.
    [19] Croce CM. Oncogenes and cancer[J]. N Engl J Med, 2008,358(5):502-511.
    [20] Strano S, Dell'Orso S, Di Agostino S, et al. Mutant p53: an oncogenic transcription factor [J]. Oncogene, 2007,26(15):2212-2219.
    [21] Reifenberger G, Liu L, I chimura, K, et al. Amplification and overexpression of the MDM2 gene in a subset of human malignant gliomas without p53 mutations[J]. Cancer Res, 1993,53(12):2736-2739.
    [22] Moll UM, Petrenko O. The MDM2-p53 interaction[J]. Mol Cancer Res, 2003, l(14):1001-1008.
    [23] Vogelstein B, Lane D, Levine AJ. Surfing the p53 network[J]. Nature,2000, 408(6810):307-310.
    [24] Toledo F, Wahl GM. Regulating the p53 pathway:in vitro hypotheses, in vivo veritas[J]. Nat Rev Cancer ,2006,6(12):90-923.
    [25] Momand J, Zambetti GP, Olson DC, et al. The mdm2-oncogene product forms a complex with the p53 protein and inhibits p53-mediated transactivation[J]. Cell, 1992,69(7): 1237-1245.
    [26] Lev Bar-Or R, Maya R, Segel LA, et al. Generation of oscillation by the p53-mdm2 feedback loop:a theoretical and experimental study[J]. Proc Natl Acad Sci USA, 2000,97(21):11250-11255.
    [27] Momand J, Zambetti GP. Mdm-2: "big brother"of p53[J]. J cell Biochem, 1997, 64(3):343-352.
    [28] Bode AM, Dong Z. The paradox of arsenic: molecular mechnisms of cell transformation and chemotherapeutic effects[J]. Crit Rev Oncol Hematol, 2002, 42:5-24.
    [29] Rajamanickam C, Jeejiabai R. Delineation of sequences essential for specific promoter activation during pressure overloaded hypertrophy or factor-induced hypertrophy[J]. Methods Mol Med, 2005,112:251-260.
    [30] Alam J, Cook JL. Reporter genes: application to the study of mammalian gene transcription[J]. Anal Biochem, 1990,188(2):245-254.
    
    [31] Elion EA. Routing MAPK cascades[J]. Sicence, 1998,281:1625-1626.
    [32] Rincon M, flavell RA, Davis RA. The JNK and p38 MAP kinase singaling pathways in T cell-mediated immune responses[J]. Free Radic Biol Med, 2000, 28(9):1328-1337.
    [33] Blume-Jensen P, Hunter T. Oncogenic kinase singnalling[J]. Nature ,2001, 411 (6835):355-365.
    [34] Fresno Vara JA, Casado E, de Castro J, et al. PI3K/AKT singnaling pathway and cancer[J]. Cancer Treat Rev, 2004,30(2): 193-204.
    [35] Itoh N, Semba S, Yamakawa M, et al. Phosphorylation of AKT/PKB is required for suppression of cancer cell apoptosis and turmor progression in human colorectal carcinoma[J]. Cancer, 2002,94(12):3127-3134.
    [36] Michael D, Oren M. The p53 and Mdm2 families in cancer[J]. Curr Opin Gene Dev,2002,12(1):53-59.
    [37] Bean LJ, Stark GR.Regulation of the accumulation and function of p53 by phosphorylation of two residues within the domain that binds to Mdm2[J]. J Biol Chem, 2002,277(3): 1864-1871.
    [38] Spandidos DA. Oncogenes and tumor suppressor genes as paradigms in oncogenesis[J]. J BUON, 2007,12:9-12.
    [39] Ziyaie D, Hupp TR, Thompson AM. P53 and breast cancer[J]. Breast, 2000, 9(5): 239-246.
    [40] Vousden KH. Activation of p53 tumor suppressor protein[J]. Biochim Biphys Acta,2002,1602(1):47-59.
    [41] Balint EE, Vousden KH. Activation and activity of the p53 tumor suppressor protein[J]. Br J cancer,2001, 85:1813-1823.
    [42] Amundson SA, Myers TG, Fornace AJ. Roles for p53 in growth arrest and apoptosis: putting on the brakes after genotoxic stress[J]. Oncogene, 1998, 17: 3287-3299.
    [43] Duesberg P, Rasnick D. Aneuploidy, the somatic mutation that makes cancer a species of its own[J]. Cell Motil Cytoskeleton, 2000,47(2):81-107.
    [44] Shiloh Y. ATM and related protein kinases: safeguarding genome integrity[J]. Nat Rev Cancer, 2003,3:155-168.
    [45] Cleaver JE, Crowley E. UV damage, DNA repair and skin carcinogenesis[J]. Front Biosci, 2002,7:1024-1043.
    
    [46] Gervin CM, Mc Culla A, Williams M, et al. Dysfunction of p53 in photocarcinogenesis [J]. Front Biosic, 2003,8:715-717.
    [47] Slee EA, O'Connor DJ, Lu X. To die or not to die :how does p53 decide[J]? Oncogene, 2004,23(16):2809-2818.
    
    [48] Lane DP. P53, guardian of the genome[J]. Nature, 1992, 358(6381):15-16.
    [49] Harris CC, Hollstein M. Clinical implications of the p53 tumor-suppressor gene[J]. New Engl J Med, 1993,329(18): 1318-1327.
    [50] Bunz F, Dutriaux A, Lengauer C, et al. Acquirement for p53 and p21 to sustain G2 arrest after DNA damage[J]. Science, 1998,282(5393): 1497-1501.
    
    [51] 王靖雪. p53和淋巴系统恶性肿瘤[J]. 国外医学儿科学分册, 2001,28(3): 131-134.
    [52] Levine AJ, Momand J, Finlay CA. The p53 tumor suppressor gene[J]. Nature, 1991,351(6326):453-456.
    [53] Hernandez L, Fest T, Cazorla M, et al. p53 gene mutations and protein overexpression are associated with aggressive variants of mantle cell lymphomes[J]. Blood, 1996, 87(8):3351-3359.
    [54] Kulms D, Schwarz T. Molecular mechanisms involved in UV-induced apoptotic cell death[J]. Skin Pharmacol Appl Skin Physiol,2002, 15(5): 342-347.
    [55] Kulms D, Schwarz T. Independent contribution of three different pathways to ul traviolet-B-induced apoptosis[J]. Biochem Pharmacol, 2002, 64(5):837-841.
    [56] Appella E, Andersen CW. Post-translational modificatioms and activation of p53 by genotoxic stress[J]. Eur J Biochem,2001, 268: 2764-2772.
    [57] Schuler M, Green DR. Mechanisms of p53-dependent apoptosis [J]. Biochem Soc Trans, 2001,29:684-688.
    [58] Bratton SB, MacFarlane M, Cain K,et al. Protein Complexes activated distinct caspase cascade in death receptor and stress-induced apoptosis[J]. Exp Cell Res, 2000,256(1):27-33.
    [59] Ash Kenazi A, Dixit VM. Death receptors: Signaling and modulation [J]. Science, 1998,281:1305-1308.
    [60] Rossman TG, Uddin AN, Burns FJ, et al. Arsenite is a cocarcinogen with solar ultraviolet radiation for mouse skin: an animal model for arsenic carcinogenesis[J]. Toxicl Appl Pharmacol, 2001, 176:64-71.
    [1] Abernathy CO, Liu Y, Longfellow D, et al. Arsenic: Health effects, mechanisma of actions, and research issues[J]. Environ Health Perspect, 1999, 107:593-600.
    [2] Kitchin KT. Recent advance in arsenic carcinogenesis: modes of action, animal model system, and methylated arsenic metabolites [J]. Toxicol And Appl Pharmacol, 2001,172:249-261.
    [3] Lin S, Cullen WR, Thomas DJ. Methylasenicals and arsinothiols are potent inhibitors of mouse liver thioredoxin reductasep[J]. Chem Res Toxicol, 1999, 12:924-930.
    [4] Petrick JS, Ayaka-Fierro F, Cullen WR, et al. Monomethylarsonous acid ( MMA(III))is more toxic than arsenite in Chang human Hepatocytes[J]. Toxicol Appl Pharmacol, 2000,163:203-207.
    [5] Marc MJ, Tennant A, Roop B, et al. Methylated arsenic(III)species react directly with DNA and are potential proximate or ultimate genotoxic forms of arsenic[J]. The Toxiologist, 2001,60:358.
    [6] Yamanaka K, Hayashi H, Tachikawa M, et al. Metabolic methylation is a possible genotoxicity-enhancing processs of inorganic arsenic [J]. Mutation Research, 1997,394:95-117.
    [7] Vijayaraghavan M, Wanibuchi H, Karim R, et al. Dimethylarsinic acid induces 8-hydroxy-2' deoxyguanosine formation in the kidney of NCI-Black Reiter rats[J]. Cancer Letters, 2001,165:11-17.
    [8] Yamanaka K, Hoshino M , Okamoto M, et al. DNA strand breaks in mammalian tissues induced by methylarsenics[J]. Biol Trace Element Res, 1991,21:413-417.
    [9] Wanibuchi H, Horri T, Meenakshi V, et al. Promotion of rat hepa-tocarcinogenesis by dimethylarsinci acid: association with elevated ornithine decarboxylase activity and formation of 8-hydroxydeoxyguanosine in the liver[J]. Japanese Journal of Cancer Research, 1997,88:1149-1154.
    [10]Le XG,Lu X,Ma M,et al.Speciation of key arsenic metabolic intermediates in human urine[J].Anal Chem,2000,72:5172-5177.
    [11]Sampayo-Reyes A,Zakharyan RA,Healy SM,et al.Monomethylarsenic acid reductase and monomethyarsonous acid in hamste tissue[J].Chem Res,2000,13:1181-1186.
    [12]Kenyon EM,Hughes MF.A concise review of the toxicology and carcinogenicity of dimethylarsenic acid[J].Toxicology,2001,160:227-236.
    [13]Brown JL,Kitchin KT,Geoge M.Dimethylarsinic acid treatment alters six different rat biochemical parameters:Relevance to arsenic carcinogenesis[J].Cancer Lett,1997,98:227-231.
    [14]邓芙蓉,李艳宏,张华明,等.亚砷酸钠和氧苯胂对人皮肤成纤维细胞缝隙连接通讯的动态影响及作用特征[J].中国药理学与毒理学杂志,2002,16(5):378-381.
    [15]Germolec DR,Spalding J,Booman GA.Arsenic can mediate skin neoplasia by chronic stimulation of keratinojte-derived growth factors[J].Mutat Res,1997,386(3):209-218.
    [16]Thomas G,Brien O.Omithine decarboxylase orerexpression is an sufficient condition for tumor promotion in mouse skin[J].Cancer Res,1997,57:2630-2637.
    [17]Deng FR,Jin Y,Wang H,et al.Phenylarsine oxide inhibits gap junctional intercellular communication between human skin fibroblast cells and dameges cellular DNA[J].J Hyg Res,2002,31(3):151-153.
    [18]Qu W,Bortner CD,Sakura T,et al.Acquisition of apoptotic resistance in arsenic-induced malignant transformation:role of the JNK signal transduction pathway[J].Carcinogenesis,2002,23:151-159.
    [19]Samet JM,Graves LM,Quay J,et al.Actiration of MAPKs in human bronchial epithelial cells exposed to metals[J].Am J Physiol,1998,275:551-558.
    [20]Wu W,Graves LM,Jaspers I,et al.Activation of the EGF receptor signaling pathway in human airway epithelial cells cxplsed to metals[J].Am J Physiol,1999,277:924-931.
    [21]Simeonova PR Wang S,Hulderman T,et al.C-Src-dependent activation of the epidermal growth factor receptor and mitogen-actirated protein kinase pathway by arsenic[J].J Biol Chem,2002,277:2945-2950.
    [22]Hasegawa A,Okada S.Induction of DNA damage by dimethylarsine,a metabolete of inorganic arsenic,is for the major part likely due to its peroxyl radical[J].Biochem Biophyl Res Commun,1990,168:58-64.
    [23]Yamanka K,Okada S.Induction of lung-specific DNA damage by metabolically methylated arsenics via the production of free radicals[J].Environ Health Perspect,1994,102:37-40.
    [24]Applegate LA,Luscher P,Tyrrell RM.Induction of heine oxygenase:a general response to oxidant stress in cultured mammalian cell[J].Cancer Res,1991,51:974-978.
    [25]Hei Tk,Liu SX,Waldren C.Mutagenicity of arsenic in mammalian cells:Role of reactire oxygen species[J].Proc Natl Acad Sci US A,1998,95:8103-8107.
    [26]Liu SX,Athar M,Lippai I,et al.Induction of oxyradicals by arsenic:Implication for mechanism of genotoxicty[J].Proc Natl Acad Sci USA,2001,98:1643-1648.
    [27]Abmad S,Kichin KT,Cullen WR.Arsenic species that cause release of iron from ferritin and generation of acitvated oxygen[J].Arch Biochem Biophys,2000,382:195-202.
    [28]刘力.DNA氧化损伤的修复及其与致癌的关系。中华劳动卫生职业病杂志,1999,17:181-183。
    [29]Loft S,Poulsen HE.Cancer risk and oxidative DNA damage in man[J].J Mol Med,1996,74:297-312.
    [30]Matsui M,Nishigori C,Toyokuni S,et al.The role of oxidative DNA damage in human arsenic carcinogenesis:detection of 8-hydnxy-2-deoxyguanosine in arsenic-related Bowen's desease[J].The Journal of Investigative Dermatology,1999,113:26-31.
    [31]Hideki W,Takaaki H,Vijayaraghavan M,et al.Promotion of rat hepatocarcinogenesis by dimethylarsini acid:association with elevated ornithine decarboxy lase actirity and formation of 8-hydnxydeoxygnanone in the liver[J].Jpn J Cancer Res,1997,88:1149-1154.
    [32]Vijayaraghavan M,Wanibuchi H,Karim R,et al.Dimethylarsenic acid induces 8-hydroxy-2'-deoxyguanosine formation in the kidney of NCI-Black-Reiter rats[J].Cancer Letters,2001,165:11-17.
    [33]张桥.卫生毒理学基础,人民卫生出版社,2000,第四版.
    [34]Brown JL,Kitchin KT.Arsenite,but not cadmium,induces ornithine decarboxylase and heme oxygenase in rat liver:relevance to arsenic carcinogenesis[J].Cancer Lett,1996,98:227-331.
    [35]Fairbairn DW,Olive PL,Neill KL.The comet assay:a comprehensive review[J].Mutation Res,1995,339:37-59.
    [36]李达圣.应用单细胞凝胶电泳比较研究砷对人类DNA的损伤[J].中国地方病学杂志.2001,20:212-216.
    [37]Yamanaka K,Hasegawa A,Sawamwra AR,et al.Cellular response to oxidative damage in lung induced by the administration of dimethylarsinic acid,a major metabolite of inorganic arsenics in mice[J].Toxicol Appl Pharrnacol,1991,108:205-213.
    [38]Giovanna T,Pier LT,Roberta B,et al.Phosphoinositide 3-kinase/AKT inhibition increases arsenic trioxide-induced apoptosis of acute promyelocytic and T-cell leukemias[J].British Journal of Haematology,2005,130:716-725.
    [39]顾军,毕新岭.砷剂与角质形成细胞及其致癌机制的研究进展[J].国外医学皮肤性病学分册,2001,27(3):150-152.
    [40]Brown JL,Kitchin KT.Arsenite,but not cadmium,induces ornithine decarboxylase and heme oxygenase in rat liver:relevance to arsenic carcinogenesis[J].Cancer Lett,1996,98:227-231.
    [41]Wanibuchi H,Hori T,Meenakshi V,et al.Promotion of rat hepatocarcinogenesis by dimethylrasinic acid:association with elevated ornithine decarboxylase activity and formation of 8-hydroxydeoxyguanosine in the liver[J].Jpn J Cancer Res,1997,,88:1149-1154.
    [42]Yamamoto S.Konishi Y.Matsuda T,et al.Cancer induction by an organic arsenic compound, dimethylarsinic acid (cacodylic acid), in F344/DuCrj rats after pretreatment with five carinogens[J]. Cancer Res, 1995,55:1271-1275.
    [43] Li JH, Rossman TG. Mechanism of comutagenesis of sodium arsenite with N-methyl-nitrosourea[J]. Biol Trace Elem, 1989,21:373-381.
    [44] Hu Y, Su L , Snow ET. Arsenic toxicity is enzyme specific and its effects on ligation are not caused by the direct inhibition on DNA repair enzymes [J]. Mutat Res, 1998,48:203-218.
    [45] Vahter M. Health effects of early life exposure to arsenic[J]. Basic Clin Pharmacol Toxicol, 2008,102(2):204-211.
    [46] Hamadeh HK, Vargas M, Lee E, et al. Arsenic disrupts cellular levels of p53 and mdm2:A potential mechanism of carcinogenesis[J]. Biochem Biophys Res Commun, 1999,263:446-449.
    [47] Salazar AM. Induction of p53 protein expression by sodium arsenite[J]. Mutat Res, 1997,381:259-265.
    [48] Mass MJ, Wang L. Arsenic alters cytosine methylation patterns of the promoter of the tumor suppressor gene p53 in human lung cells:A model for a mechanism of a carcinogenesis[J]. Mutat Res, 1997,263:446-449.
    [49] Zhao CQ, Young MR, Diwan BA, et al. Association of arsenic-induced malignant transformation with DNA hypomethylation and aberrant gene expression[J]. Proc Natl Aca Sci USA, 1997,386:263-277.
    [50] Lee TC, Tanaka N, Lamb PW, et al. Induction of gene amplification by arsenic[J]. Science, 1998,241:80-81.
    [51] Woloson D. Gene amplification in SV40 transformed human keratinocytes. Ph. D. Thesis, New York Universty Medical School. New York 1990.
    [52] Katakura K. DNA amplification in Leishmania resistant to both arsenite and methotrexate[J]. Mol Biochem Paresetol, 1999,34:189-192.
    [53] Liu J, Liu Y, Gorer RA, et al. Acute arsenic induced free radical production and oxidative stress-related gene experssion in mice[J]. Toxicol Sci 2000, 54: 1314- 1321.
    [54] National Research Council (NRC) Report. Arsenic in drinking water. Washington DC:National Academy Press, 1999: 194-196.
    [55] Wanibuchi H, Yamamoto S, Chen H, et al. Promoting effects of dimethylarsinic acid on N butyl N (4 hydroxybutyl) nitrosamine induced urinary bladder carcinogenesis in rats[J]. Carcinogenesis, 1996 , 172 (11) :2435-2439.
    [56] Wei M, Wanibuchi H, Yamamoto S, et al. Urinary bladder carcinogenicity of dimethylarsinic acid in male F344 rats[J]. Carcinogenesis, 1999, 20 (9): 1873- 1876.
    [57] Yamanaka K, Ohtsubo K, Hasegawa A, et al. Exposure to dimethylarsinic acid, a main metabolite of inorganic arsenics, strongly promotes tumorigenesi initiated by 4 nitroquinoline 1 oxide in the lungs of mice[J]. Carcinogenesis, 1996 , 17 (4): 767-770.
    [58] Hayashi H, Kanisawa M, Yamanaka K, et al. Dimethylarsenic acid, a main metabolite of inorganic arsenics, has tumorigenicity and progression effects inthe pulmonary tumors of A/J mice[J]. Cancer Lett, 1998 , 125:83-88.
    [59] Yamanaka K, Katsumaka K, Ikuma K, et al. The role of orally administered dimethylarsinic acid, a main metabolite of inorganic arsenics, in the promotion and progression of UVB-induced skin tumorigenesis in haireless mice[J]. Cancer Lett, 2000, 152: 79-85.
    [60] Yamanaka K, Mizol M, Kato K, et al. Oral administration of dimethylarsinic acid, a main metabolite of inorganic arsenic, in mice promotes skintumorigenesis initiated by dimethylbenz(a)anthracene with or without ultraviolet B as a promoter[J]. Biol Pharm Bull, 2001 , 24 (5) :510-514.
    [61] International Agency Research on Cancer (IARC). Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Humans, Vol. 1242, Suppl. 7: Overall Evaluationsof Carcinogenicity: An Updating of IARC Monographs. IARC, Lyon, 1987 , 100-106.
    [62] Salim EI, Wanibuchi H, Morimura K, et al. Carcinogenicity of dimethylarsinic acid in p53 heterozygous knockout and wild type C57BL/6J mice[J]. Carcinogenesis, 2003 , 24 (2): 335-342.
    [63] Popovicova J, Moser GJ, Goldsworthy TL, et al. Carcinogenicity and co-carcinogenicity of sodium arsenite in p53 +/- male mice[J]. Toxicologist, 2000, 54: 134.
    [64] Kitchin KT, BrownJL , Kulkarni AP. Ornithine decarboxylase induction and DNA damage as a predictive assay for potential carcinogenicity[J]. Prog Clin Biol Res, 1991,369: 137-144.
    [65] Chen NY, Ma WY, Huang C, et al. Activation of PKC is required for arsenite-induced signal transduction[J]. J Environ Pathol Toxicol Oncol, 2000 , 19 (3): 297-305.
    [66] Gemolec DR, Spalding T, Yu HS, et al. Arsenic enhancement of skin neoplasia by chronic stimulation of growth factors[J]. Am J Pathol, 1998, 153: 1775- 1785.

© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号

地址:北京市海淀区学院路29号 邮编:100083

电话:办公室:(+86 10)66554848;文献借阅、咨询服务、科技查新:66554700