摘要
大肠癌,包括结肠癌和直肠癌,是威胁人类生命健康的常见消化道恶性肿瘤。放射治疗是大肠癌的主要治疗手段之一,但放射治疗大肠癌的辐射耐受现象严重影响大肠癌病人的疗效,放疗抵抗性成为大肠癌放疗面临严峻且迫切需要解决的难题。电离辐射后细胞DNA损伤的修复是肿瘤放疗效果不佳的主要原因之一。X射线修复交叉互补(X-ray repair cross complementing, XRCC)基因家族(XRCC1～XRCC11)对电离辐射诱导的DNA损伤修复发挥重要作用。DNA损伤通过碱基切除修复、核苷酸切除修复、错配修复、同源重组修复(homologous recombination,HR)和非同源末端连接(non-homologous end joining, NHEJ)等多种方式进行修复,从而维持生物体基因组的完整性和抑制肿瘤的发生。XRCC2是重要的参与HR途径的基因之一,其高表达与增加辐射诱导的DNA损伤抵抗有关。XRCC2基因修复缺陷表现出对电离辐射的敏感性增高,而XRCC2蛋白过表达则对放射线耐受。提示通过抑制肿瘤细胞XRCC2的表达,有可能提高临床肿瘤放射治疗的敏感性。目前尚未见到关于大肠癌中XRCC2表达水平以及XRCC2与放射敏感性关系的研究报道。降低XRCC2的表达是否可以改变大肠癌细胞的放射敏感性,XRCC2是否可以预测大肠癌放射治疗的疗效,目前在国内外未见相关的研究报道。
目的：本实验通过大肠癌体外细胞模型和体内动物模型,探讨shRNA介导的XRCC2基因沉默是否影响大肠癌细胞的放疗敏感性及其疗效,阐明XRCC2在大肠癌放疗敏感性中的关键作用和初步相关机制。
方法：(1)体外细胞实验：将shRNA-XRCC2转染人大肠癌T84细胞以沉默XRCC2基因表达,采用蛋白免疫印迹法和实时定量PCR法检测沉默XRCC2基因的效率；采用MTT法检测T84细胞的增殖。经X-射线照射后,采用克隆形成法检测T84细胞的放射敏感性；采用碱性“彗星”电泳法测定T84细胞的DNA损伤修复；流式细胞术检测T84细胞的细胞周期；Annexin V-FITC/PI双染法检测T84细胞的细胞凋亡率。(2)体内细胞实验：同时将shRNA-XRCC2转染的大肠癌T84细胞接种于BALB/c裸鼠建立移植瘤模型,进行X-射线照射,检测肿瘤的体积和重量变化,并对肿瘤组织进行病理分析。
结果：(1)在体外细胞实验中,shRNA-XRCC2转染有效抑制了T84细胞中XRCC2蛋白和mRNA的表达。经嘌呤酶素筛选,得到了稳定的XRCC2基因沉默的大肠癌T84细胞系。细胞生长曲线表明,沉默XRCC2表达明显抑制了T84细胞的增殖。克隆形成实验显示,XRCC2基因沉默的T84细胞经X-射线照射后,克隆形成数目显著减少,表明XRCC2基因沉默提高了T84细胞的放射敏感性。彗星实验表明,沉默XRCC2表达的T84细胞DNA损伤增多,DNA损伤修复能力下降。流式细胞术检测显示,XRCC2基因沉默显著诱导了辐射导致的细胞凋亡和细胞阻滞在G2/M期。(2)在体内细胞实验中,转染shRNA-XRCC2的裸鼠种植瘤生长缓慢,肿瘤体积和重量明显减少。肿瘤病理组织学分析表明,转染shRNA-XRCC2的肿瘤组织核分裂相减少,多见大小不等的坏死区。说明沉默XRCC2表达提高了裸鼠大肠癌对辐射的敏感性,肿瘤生长受到明显的抑制作用。
结论：shRNA介导的XRCC2基因沉默有效抑制了体外大肠癌细胞和体内裸鼠大肠癌肿瘤的生长,沉默XRCC2表达对体外和体内大肠癌细胞对X射线的反应具有一致性,即均提高了大肠癌对放射的敏感性。提示XRCC2有希望在大肠癌的临床放射治疗敏感性中作为一重要的靶向基因。
Colorectal cancer, including colon cancer and rectal cancer, is one of the most common tumors of the digestive tract threatening the human life and health seriously. Although radiotherapy is one of methods of colorectal cancer treatment, the radioresistance in radiotherapy seriously affects the curative effect of colorectal cancer patients. DNA damage's repair after exposure to ionizing radiation is one of reasons of tumors resistance to radiotherapy. X-ray repair cross complementing gene family (XRCC1-XRCC11) plays an important role in repairing DNA damages induced by ionizing radiation. DNA damages are repaired by various mechanisms such as base excision repair, nucleotide excision repair, mismatch repair, homologous recombination and non-homologous end joining pathways to maintain the integrity of the genetic information and inhibit the formation of tumors. XRCC2is the key protein of DNA homologous recombination repair pathway, and its high expression is associated with enhanced resistance to DNA damage induced by ionizing radiation. XRCC2gene defects in some cell lines show an increased sensitivity to radiation, whereas the abnormal upregulation of XRCC2gene expression renders tumor cells resistance to radiation. Thus, we propose that the inhibiting of XRCC2expression in tumor cells may enhance their radiosensitivity. However, the studies on XRCC2expression in colorectal cancer and its association with sensitivity to radiation were not found. Until now, it is not yet known whether lowering XRCC2expression can affect the sensitivity of radiotherapy for colorectal cancer or XRCC2can predict the efficacy of colorectal cancer radiotherapy.
Objective:The goal of the project is to study the effects of XRCC2gene silencing mediated by shRNA on radiosensitivity of colorectal cancer cells in vitro and in vivo and to elucidate the relationship between XRCC2role and the mechanism of colorectal cancer radiotherapy.
Methods:The vector-based shRNA plasmid (shRNA-XRCC2) was transfected into colorectal cancer T84cell line to silence XRCC2gene expression. The efficiency of XRCC2silencing was determined by western blot and real-time PCR analyses. The growth curve of T84cells in vitro was examined by MTT assay. The effect of XRCC2suppression on T84cells'radiosensitivity to X-radiation was examined by colony formation assay. DNA damage's repair of T84cells was determined by alkaline comet assay. The relationship between the sensitivity of T84cells to radiation and the cell cycle distribution or cell apoptosis was performed by flow cytometric analysis. Colorectal cancer T84cells transfected shRNA-XRCC2were transfered into BALB/c nude mice to establish a xenograft model in vivo.The curative effect and pathological analysis of xenografts were investigated after xenograft received radiotherapy.
Results:(1) In vitro:XRCC2protein and mRNA expression of colorectal cancer T84cells was effectively silenced by shRNA-XRCC2transfection. Colorectal cancer T84cell line silencing XRCC2gene expression stablely was achieved successfully through selecting with purine enzyme. Knockdown of XRCC2expression by shRNA inhibited cell growth of T84cells as evaluated by MTT assay. The number of colonies formed in shRNA-XRCC2cells was significantly decreased, which showed that shRNA-mediated XRCC2suppression rendered T84tumor cells more sensitive to radiation treatment. DNA damages were increased and the capability of DNA damage's repair was decreased in T84cells as examined by comet assay. Suppression of XRCC2expression resulted in an elevation of cell apoptosis and cell cycle arrested in G2/M phase induced by radiation through flow cytometric analysis.(2)In vivo:Tumor xenograft transfected with shRNA-XRCC2in nude mice grew slowly and the tumor volume and the tumor weight were decreased significantly. Pathological analysis showed that karyokinesis was decreased and small areas of necrosis were found in tumor xenograft treated by shRNA-XRCC2transfection. The data suggested that knockdown of XRCC2expression enhanced the tumor's sensitivity to radiation in nude mice and tumor xenograft's growth was retarded.
Conclusion:XRCC2gene silencing mediated by shRNA inhibited the growth of colorectal tumor cells in vitro and in vivo and has radiosensitization effects on colorectal tumor cells in vitro and in vivo, ie. increased tumor's sensitivity to radiation. These data strongly suggested that XRCC2may be further developed as a promising therapeutic target for the treatment of radioresistant human colorectal cancer.
引文
1. Jemal A, Bray F, Center MM, et al. Global cancer statistics. CA Cancer J Clin,2011, 61:69.
2. Center MM, Jemal A, Smith RA, et al. Worldwide variations in colorectal cancer. CA Cancer J Clin,2009,59(2):366-378.
3. Center MM, Jemal A, Ward E. International Trends in Colorectal Cancer Incidence Rates. Cancer Epidemiol Biomarkers Prev,2009,18(6):1688-1694.
4. Ganapathi S, Kumar D, Katsoulas N, et al. Colorectal cancer in the young:trends, charactistics and outcome. Int J Colorectal,2011,26(7):927-934.
5.林海,徐文彤.生物技术在肿瘤治疗中的作用.中国药房,2008,19(25)：1986-1987
6.朱小杨.立体适形放疗在原发性肝癌中的应用进展.中华现代内科学杂志,2006,3(9)：1002-1004.
7.张梦达,王爱玲,郭杰,等.电离辐射对心脏介入患者淋巴细胞DNA损伤的影响.安徽医科大学学报,2013,48(10)：1217-1220
8.陈英.辐射所致DNA损伤与肿瘤风险.癌变畸变突变,2011,23(6)：473-475
9.由莉,赵永成.电离辐射所致的DNA双链断裂检测技术的进展.中国辐射卫生,2006,15(3)：381-382
10.王芹.X射线修复交叉互补基因功能的研究进展.国际放射医学核医学杂志,2005,29(3)：132-136.
11. Du LQ, Wang Y, Wang H, et al. Knockdown of Rad51 expression induces radiation-and chemo-sensitivity in osteosarcoma cells. Med Oncol,2011,28(4):1481-1487.
12.王芹,刘强,孙元明,等.X射线交叉互补修复基因多态性与肿瘤,国际放射医学核医学杂志,2013,37(6),370-373.
13. Uphoff S, Kapanidis AN. Studying the organization of DNA repair by single-cell and single-molecule imaging. DNA Repair (Amst).2014 Mar 11. pii: S1568-7864(14)00053-6.
14. Abbotts R, Thompson N, Madhusudan S. DNA repair in cancer:emerging targets for personalized therapy. Cancer Manag Res.2014,6:77-92
15. Li Y, Reynolds P, O'Neill P, Cucinotta FA. Modeling damage complexity-dependent non-homologous end-joining repair pathway. PLoS One,2014,9(2):e85816.
16.王芹.DNA双链断裂修复途径中重要的修复蛋白,国际放射医学核医学杂志,2013,37(1)：34-37.
17. Cappelli E, Townsend S, Griffin C, et al. Homologous recombination proteins are associated with centrosomes and are required for mitotic stability. Exp Cell Res,2011, 317(8):1203-1213.
18. Romanowicz H, Smolarz B, Baszczynski J, et al. Genetics polymorphism in DNA repair genes by base excision repair pathway (XRCC1) and homologous recombination (XRCC2 and RAD51) and the risk of breast carcinoma in the Polish population. Pol J Pathol,2010,61(4):206-212.
19. Tambini CE, Spink KG, Ross CJ, et al. The importance of XRCC2 in RAD51-related DNA damage repair. DNA Repair (Amst),2010,9(5):517-525.
20. Rajesh C, Gruver AM, Basrur V, et al. The interaction profile of homologous recombination repair proteins RAD51C, RAD51D and XRCC2 as determined by proteomic analysis. Proteomics,2009,9(16):4071-4086.
21. Date O, Katsura M, Ishida M, et al. Haploinsufficiency of RAD51B causes centrosome fragmentation and aneuploidy in human cells. Cancer Res,2006, 66(12):6018-6024.
22. Park SW, Yoo NJ, Lee SH. Mutational analysis of mononucleotide repeats in XRCC2 and XRCC6 in cancers with microsatellite instability. Pathology,2011, 43(1):78-79.
23. Haines JW, Coster MR, Adam J, et al. Xrcc2 modulates spontaneous and radiation-induced tumorigenesis in Apcmin/+mice]. Mol Cancer Res,2010, 8(9):1227-1233.
24. Liu Y, Shete S, Wang LE, et al. Gamma-radiation sensitivity and polymorphisms in RAD51L1 modulate gliomarisk. Carcinogenesis,2010,31(10):1762-1769.
25. Kuhne M, Riballo E, Rief N, et al. Double-strandbreak repair defect in ATM-deficient cells contributes to radiosensitivity. Cancer Res,2004,64(2):500-508
26.史卫林,李坚,陈萍等.X线对肺癌细胞株A549 XRCC2和XRCC3表达水平的影响.南京医科大学学报(自然科学版),2009,29(11)：1517-1520.
27. Allal AS, Kahne T, Reverdin AK, et al. Radioresistance-related proteins in rectal cancer. Proteomics,2004,4(8):2261-2269.
28. Gollis SJ, Tighe A, Seott SD, et al. Ribozyme minigenemediated RAD51 down-regulation increases radiosensitivity of human prostate cancer cells. Nucleic Acids Res,2001,29 (7):1534-1538
29. Lee YJ, Sheu TJ, Keng PC. Enhancement of radiosensitivity in H1299 cancer cells by actin-associated protein cofilin. Biochem Biophys Res Commun,2005,335(2): 286-291
30. Zheng Z, Ng WL, Zhang X, et al. RNAi-mediated targeting of noncoding and coding sequences in DNA repair gene messages efficiently radiosensitizes human tumor cells. Cancer Res,2012,72(5):1221-1228.
31. Lin WY, Camp NJ, Cannon-Albright LA, et al. A role for XRCC2 gene polymorphisms in breast cancer risk and survival. Med Genet,2011,48(7):477-484.
32. Shamseldin HE, Elfaki M, Alkuraya FS. Exome sequencing reveals a novel Fanconi group defined by XRCC2 mutation. J Med Genet,2012,49(3):184-186.
33. Silva SN, Tomar M, Paulo C, et al. Breast cancer risk and common single nucleotide polymorphisms in homologous recombination DNA repair pathway genes XRCC2, XRCC3, NBS1 and RAD51. Cancer Epidemiol,2010,34(1):85-92.
34. Bastos HN, Antao MR, Silva SN, et al. Association of polymorphisms in genes of the homologous recombination DNA repair pathway and thyroid cancer risk. Thyroid,2009,19(10):1067-1075.
35. Pearce CL, Near AM, Van Den Berg DJ, et al. Validating genetic risk associations for ovarian cancer through the international ovarian cancer association consortium. Br J Cancer,2009,100(2):412-420.
36. Krupa R, Sliwinski T, Wisniewska-Jarosinska M, et al. Polymorphisms in RAD51, XRCC2 and XRCC3 genes of the homologous recombination repair in colorectal cancer-a case control study. Mol Biol Rep,2011,38(4):2849-2854.
37. Slattery ML, Curtin K, Wolff RK, et al. A comparison of colon and rectal somatic DNA alterations. Dis Colon Rectum,2009,52(7):1304-1311.
38. Curtin K, Lin WY, George R, et al. Meta association of colorectal cancer confirms risk alleles at 8q24 and 18q21. Cancer Epidemiol Biomarkers Prev,2009, 18(2):616-621.
39. Curtin K, Lin WY, George R, et al. Genetic variants in XRCC2:new insights into colorectal cancer tumorigenesis. Cancer Epidemiol Biomarkers Prev,2009, 18(9):2476-2484.
40. Reeves SG, Meldrum C, Groombridge C, et al. DNA repair gene polymorphisms and risk of early onset colorectal cancer in Lynch syndrome. Cancer Epidemiol,2012, 36(2):183-189.
41. Napoli CD, Lemieux C, Jorgensen. Introduction of a chalcone synthase gene into petunia results in reversible co-suppression of homologous gene in trans. Plant Cell, 1990,2:279-289.
42. Fire A, Xu S, Montgometry MK, et al. potent and specific genetic interference by double-stranded RNAin Caenorhabditis elegans. Nature,1998,391(6669):806-811.
43. Tabara H, Grishock A, Mello CC. RNAi C.elegans:soaking in the genome sequence. Science,1998,282(5388):430-431.
44. Bernstein E, Caudy AA, Hammond SM, et al. Role for a bidentate ribonuclease in the initiation step of RNA interference. Nature,2001,409 (6818):3632366.
45.杨媛,王蒙.RNAi作用机制研究进展及其应用.免疫学杂志,2005,21(6)：543-545
46.孙绍娟,王鸿程,许学亮,等.RNA干扰技术沉默STAT3对人肺癌细胞生长抑制的作用,肿瘤防治研究,2007,34(8)：565-567
47. Qi YH, Yao WL, Zhang CH, et al. Effect of lentivirus-mediated RNA interference of APC-Cdhl expression on spinal cord injury in rats. Genet Mol Res.2014, 13(1):1366-1372
48.何巍,李玉霞,刘佳,等.RNA干扰下调Slug表达对肺癌细胞A549的细胞周期、增殖和侵袭的影响.中国肿瘤生物治疗杂志,2013,20(6)：685-689
49. Ying X, Zhang R, Wang H, Teng Y. Lentivirus-mediated RNAi knockdown of LMP2A inhibits the growth of nasopharyngeal carcinoma cell line C666-1 in vitro. Gene.2014 Mar 12. pii:S0378-1119(14)00298-4.
50.周渊,王汉东,纪祥军,等.RNA干扰下调Nrf2对U251细胞自噬的影响.中华神经外科疾病研究杂志,2013,12(6)：509-512
51. Asada S, Watanabe S, Fujii T, et al. RNAi Knockdown of Potent Sugar Sensor in Cellulase-Producing Fungus Acremonium cellulolyticus. Appl Biochem Biotechnol. 2014,172(6):3009-3015
52. Smialowska A, Djupedal I, Wang J, et al. RNAi mediates post-transcriptional repression of gene expression in fission yeast Schizosaccharomyces pombe. Biochem Biophys Res Commun.2014,444(2):254-259
53.陈艳媛,廖慧娟,张灵,等.RNA干扰CD147稳定表达前列腺癌PC-3细胞株的建立.吉林医药学院学报,2013,34(6)：404-406
54.贾秀红,尹宝慧,李建厂.RNA干扰HOXA7联合甲氨蝶呤对U937细胞增殖、凋亡的影响.实用医学杂志,2013,29(20)：3285-3288
55.孝飞飞,贾秀红,李建厂.RNA干扰抑制Apollon表达联合川芎嗪可增强白血病细胞对化疗药物的敏感性.肿瘤,2013,33(11)：973-979
56. Mollaie HR, Monavari SH, Arabzadeh SA, et al. RNAi and miRNA in viral infections and cancers. Asian Pac J Cancer Prev.2013,14(12):7045-7056
57.邹燕梅,熊华,肖志平,等.RNAi沉默HIF-1a基因调控乏氧肺腺癌A549细胞放射敏感性和白噬能力.中国癌症杂志,2013,23(6)：413-419
58. Sado K, Ayusawa D, Enomoto A, et al. Identification of a mutated DNA ligase IV gene in the X-ray-hypersensitive mutant SX10 of mouse FM3A cells. J Biol Chem, 2001,276(13):9742-9748
59. Sak A, Stuschke M, Wurm R, et al. Selective inactivation of DNA-dependent protein kinase with antisense oligodeoxynucleotides:consequences for the rejoining of radiation-induced DNA double-strand breaks and radio sensitivity of human cancer cell lines. Cancer Res,2002,62(22):6621-6624
60.赵维勇,刘志远,毕良文,等.多西紫杉醇对大肠癌细胞放射增敏的作用研究 中国医药导报,2013,10(34)：10-13
61.竺炎,吴传高,刘少平,等.干扰Wrap53基因调控人骨肉瘤U20S细胞放射敏感性实验研究,中华肿瘤防治杂志,2013,20(21)：1657-1660
62. Yuki HIROTA, Shin-Ichiro MASUNAGA, Natsuko KONDO, et al. High linear-energy-transfer radiation can overcome radioresistance of glioma stem-like cells to low linear-energy-transfer radiation. Journal of Radiation Research,2013, 1-9
63.刘小群,乔田奎.厄洛替尼对人肺腺癌A549细胞的放射增敏作用.中华肿瘤杂志,2013,35(11)：819-823
64. Ainars Bajinskis, Adayapalam T. Natarajan, Klaus Erixon, et al. DNA double strand breaks induced by the indirect effect of radiationare more efficiently repaired by non-homologous end joiningcompared to homologous recombination repair. Mutat Res.2013,756(l-2):21-29
65.李鹏,刘江伟,袁芳,等.siRNA干扰S100A4mRNA对人胰腺癌细胞放射敏感性的影响,中华肝胆外科杂志,2013,19(10)：777-781
66. Zhuang HQ, Bo QF, Yuan ZY, et al.The different radiosensitivity when combining erlotinib with radiation at different administration schedules might be related to activity variations in c-MET-PI3K-AKT signal transduction. Onco Targets Ther.2013, 603-608.
67. OSTLING O, Johnson KJ. Microelectrophoretic study of radiation-induced DNA damages in individual mammalian cells[J]. Biochem Biophys Res Commun,1984,12 3(1):291-298.
68.赵静珺,肖卫,刘银梅,等.硫酸铟对V79细胞DNA损伤作用的彗星实验.工业卫生与职业病,2011,37(3)：149-152
69. Collins A R. The comet assay for DNA damage and repair:principles, applications, and limitations. Mol Biotechnol.2004,26(3):249-61
70.郭红刚,杨建一,高宝珍,等.利用彗星实验检测丙烯酰胺对小鼠两种细胞的DNA损伤和修复,生态毒理学报,2007,2(2)：232-236
71.林林,孙树秋.脱氧雪腐镰刀菌烯醇致Vero细胞核基因组DNA损伤与修复的彗星实验观察,中国地方病防治杂志,2004,19(3)：139-141
72. Praveen Kumar MK, Shyama SK, Sonaye BS, et al. Evaluation of y-radiation-induced DNA damage in two species of bivalves and their relative sensitivity using comet assay. Aquat Toxicol.2014 Feb 20;150C:1-8
73.赵琳娜,陈薛钗,钟儒刚,等.单细胞凝胶电泳技术检测DNA损伤的方法及进展,生物学杂志,2013,30(3)：85-71
74. Jafari M, Rezaei M, Kalantari H, et al. Determination of Cell Death Induced by Lovastatin on Human Colon Cell Line HT29 Using the Comet Assay. Jundishapur J Nat Pharm Prod.2013,8(4):187-191
75. Kalantari H, Rezaei M, Salehcheh M, et al. Determination of the mutagenicity potential of dillsun herbal medicine by single cell gel electrophoresis in rat hepatocytes. Jundishapur J Nat Pharm Prod.2013,8(2):55-59
76.张静,杨桂文,刘大胜.单细胞凝胶电泳检测Pb2+对小鼠淋巴细胞DNA的损伤,安徽农业科学,2012,40(10)：5955-5957
77. Moller PR. Genotoxicity of environmental agents assessed by the alkaline comet assay. Basic Clin Pharmacol Toxicol.2005,96 (Suppl):1-42
78. Johnson LA, Ferris JA. Single cell electrophoresis in determining cell death:potential for use in organ transplant research. Biochem Biophys Methods, 2005,63(1):53-68.
79. Jenner TJ, Fulford J and O'Neill P. Contribution of base lesions to radiation-induced clustered DNA damage:implication for models of radiation response. Radiat Res, 2001,156(5 Pt 2):590-593
80. Emanuele E, Spencer JM, Braun M. From DNA repair to proteome protection:new molecular insights for preventing non-melanoma skin cancers and skin aging. J Drugs Dermatol.2014,13(3):274-281
81. Moore S, Stanley FK, Goodarzi AA. The repair of environmentally relevant DNA double strand breaks caused by high linear energy transfer irradiation-No simple task. DNA Repair (Amst).2014 Feb 21. pii:S1568-7864(14)00025-1
82. Carvalho JF, Kanaar R. Targeting homologous recombination-mediated DNA repair in cancer. Expert Opin Ther Targets.2014,18(4):427-458
83.王作书,胡海燕,张志茹,等.pEgrl-AIF△1-480质粒联合电离辐射对人乳腺癌MDA-MB-231细胞周期及凋亡的作用.中国老年学杂志,2012,32(18)：3968-3970
84.邹联洪,徐勤枝,刘晓丹,等.TAB182对电离辐射诱发细胞周期G2/M阻滞的调节作用.中国生物化学与分子生物学报,2012,28(9)：811-817
85.樊嵘,刘晓丹,王豫,等.Tip60过表达对细胞DNA辐射损伤修复及细胞周期的影响.辐射防护,2012,32(2)：81-87
86.郑红,周平珅,汪思应,等.DNA损伤应答与DNA双链断裂修复,中华放射医学与防护杂志,2007,27(6)：607-610
87.郭传玲,王菊芳,李文建,等.细胞辐射敏感性与DNA双链断裂及修复相关性研究,中华放射医学与防护杂志,2007,27(3)：303-306
88.张寒,郑胡镛.丝氨酸/精氨酸富集剪接因子1在肿瘤发生发展过程中的作用,中国肿瘤生物治疗杂志,2013,20(6)：631-636
89.田云鹏.P53基因与肿瘤的研究进展,疾病监测与控制,2013,7(12)：740-736
90. Pawlik, T.M, Keyomarsi, K. Role of cell cycle in mediating sensitivity to radiotherapy. Int. J. Radiat. Oncol. Biol. Phys.2004,59,928-942.
91. Thacker J, Zdzienicka MZ. The XRCC genes:expanding roles in DNA double-strand break repair. DNA Repair (Amst),2004,3 (8-9):1081-1090.
92. Yunlan L, Juan Z, Qingshan L. Antitumor Activity of Di-n-Butyl-(2,6-Difluorobenzohydroxamato)Tin(IV) against Human Gastric Carcinoma SGC-7901 Cells via G2/M Cell Cycle Arrest and Cell Apoptosis. PLoS One.2014,9(3):e90793
93. Kerr JF, Wyllie AH, Currie AR. Apoptosis:a basic biological phenomenon with wide-ranging implications in tissue kinetics. Br J Cancer,1972,26(4):239-57.
94. Mishra R, Karande AA. Endoplasmic Reticulum Stress-Mediated Activation of p38 MAPK, Caspase-2 and Caspase-8 Leads to Abrin-Induced Apoptosis. PLoS One. 2014,9(3):e92586
95. Wu X, Deng G, Hao X, et al. A Caspase-Dependent Pathway Is Involved in Wnt/β-Catenin Signaling Promoted Apoptosis in Bacillus Calmette-Guerin Infected RAW264.7 Macrophages. Int J Mol Sci.2014,15(3):5045-5062
96. Jin J, Lin G, Huang H, et al. Capsaicin Mediates Cell Cycle Arrest and Apoptosis in Human Colon Cancer Cells via Stabilizing and Activating p53. Int J Biol Sci.2014, 10(3):285-295
97. Mendoza FJ, Espino PS, Cann KL, et al. Anti-tumor chemotherapy utilizing peptide-based approaches--apoptotic pathways, kinases, and proteasome as targets. Arch Immunol Ther Exp (Warsz),2005,53(1):47-60.
98. Hunter AM, Kottachchi D, Lewis J, et al. A novel ubiquitin fusion system bypasses the mitochondria and generates biologically active Smac/DIABLO. J Biol Chem, 2003,278(9):7494-9.
99. Hanahan D, Weinberg RA. The hallmarks of cancer. Cell,2000,100(1):57-70.
100.肖绍文,张珊文,吕有勇,等.外源性p53基因对人胃癌细胞的放射增敏作用.北京大学学报(医学版),2001,33(5)：427-431.
101.崔滨滨,刘明,赵鹏,等.重组腺病毒介导的野生型p53基因对结直肠癌细胞的放射治疗增敏作用.中华外科杂志,2005,(43)15：1002-1005.
102. Yu Y, Li CY and Little JB. Abrogation of p53 function by HPV16 E6 gene delays apoptosis and enhances mutagenesis but does not alter radiosensitivity in TK6 human lymphoblast cells. Oncogene,1997,14(14):1661-1667
103. Rengarajan T, Nandakumar N, Rajendran P, et al. D-Pinitol Promotes Apoptosis in MCF-7 Cells via Induction of p53 and Bax and Inhibition of Bcl-2 and NF-κB. Asian Pac J Cancer Prev.2014,15(4):1757-1762
104. Xiao Q, Hu Y, Liu Y, et al. BEX1 Promotes Imatinib-Induced Apoptosis by Binding to and Antagonizing BCL-2. PLoS One.2014,9(3):e91782
105. Ledoux D, Hamma KY, Dibenedtto M, et al. A new dimethyl ester bisphosphonate inhibits angiogenesis and growth of human epidermoid carcinoma xenograft in nude mice. Anticancer Drugs,2006,17(4):479-85.
106. Ma W, Ma L, Zhe H, et al. Detection of esophageal squamous cell carcinoma by cathepsin B activity in nude mice. PLoS One.2014,9(3):e92351.
107.李玉,董丹,阎英.肿瘤辐射增敏机制研究进展.国际放射医学核医学杂志,2007,31(1)：48-50
108.顾菲,刘晓秋.肿瘤辐射增敏的分子机制.国际放射医学核医学杂志,2006, 30 (5):298-301
109. Shi, W.L.; Li, J.; Chen, P.; Dai, C.H. Effect of X-ray on expression levels of XRCC2 and XRCC3 in lung cancer cell line A549. Acta Univ. Med. Nanjing Nat. Sci.2009,29,1517-1520.
[1]Demuth I, Digweed M. T The clinical manifestation of a defective response to DNA double-strand breaks as exemplified by Nijmegen breakage syndrome. Oncogene, 2007,26(56):7792-7798.
[2]Yano K, Morotomi-Yano K, Adachi N, et al. Molecular mechanism of protein assembly on DNA double-strand breaks in the non-homologous end-joining pathway. J Radiat Res,2009,50(2):97-108.
[3]Liu Y, Tarsounas M, O'regan P, et al. Role of RAD51C and XRCC3 in genetic recombination and DNA repair. J Biol Chem,2007,282(3):1973-1979.
[4]杨青山,樊飞跃.Ku蛋白与DNA修复.国际放射医学核医学杂志,2008,32(1)：40-43.
[5]程晋.DNA损伤修复及细胞周期检控点激活的研究进展.国际放射医学核医学杂志,2009,33(6)：360-364.
[6]Roberts SA, Ramsden DA. Loading of the nonhomologous end joining factor, Ku, on protein-occluded DNA ends. J Biol Chem,2007,282(14):10605-10613.
[7]Mari PO, Florea BI, Persengiev SP, et al. Dynamic assembly of end-joining complexes requires interaction between Ku70/80 and XRCC4. Proc Natl Acad Sci USA,2006,103(49):18597-18602.
[8]Evans JW, Liu XF, Kirchgessner CU, et al. Induction and repair of chromosome aberrations in scid cells measured by premature chromosome condensation. Radiat Res,1996,145(1):39-46.
[9]Simsek D, Jasin M. Alternative end-joining is suppressed by the canonical NHEJ component Xrcc4-ligase IV during chromosomal translocation formation. Nat Struct Mol Biol,2010,17(4):410-416.
[10]Nasiri M, Saadat I, Omidvari S, et al. Genetic variation in DNA repair gene XRCC7 (G6721T) and susceptibility to breast cancer. Gene,2012,505(1):195-197.
[11]Shammas MA, Shmookler Reis RJ, Koley H, et al. Dysfunctional homologous recombination mediates genomic instability and progression in myeloma. Blood, 2009,113(10):2290-2297.
[12]Kuznetsov SG, Haines DC, Martin BK, et al. Loss of Rad51c leads to embryonic lethality and modulation of Trp53-dependent tumorigenesis in mice. Cancer Res, 2009,69(3):863-872.
[13]王芹.X射线修复交叉互补基因功能的研究进展.国外医学放射医学核医学分册,2005,29(3)：132-136.
[14]Tambini CE, Spink KG, Ross CJ, et al. The importance of XRCC2 in RAD51-related DNA damage repair. DNA Repair (Amst),2010,9(5):517-525.
[15]Johnson RD, Liu N, Jasin M. Mammalian XRCC2 promotes the repair of DNA double-strand breaks by homologous recombination. Nature,1999,401(6751): 397-399.
[16]张占春.电离辐射损伤与DNA修复基因.国外医学放射医学核医学分册,2004,28(1)：26-29.
[17]Fan S, Meng Q, Auborn K, et al. BRCA1 and BRCA2 as molecular targets for phytochemicals indole-3-carbinol and genistein in breast and prostate cancer cells. Br J Cancer,2006,94(3):407-426.
[1]程晋.DNA损伤修复及细胞周期检控点激活的研究进展.国际放射医学核医学杂志,2009,33(6)：360-364.
[2]张占春.电离辐射损伤与DNA修复基因.国际放射医学核医学杂志,2004,28(1)：26-29.
[3]杨青山.Ku蛋白与DNA修复.国际放射医学核医学杂志,2008,32(1)：40-43.
[4]任振义,金一尊.Ku蛋白在肿瘤发生中的作用及其靶向抑制策略.国际放射医学核医学杂志,2008,32(5)：305-307.
[5]王芹.X射线修复交叉互补基因功能的研究进展,国际放射医学核医学杂志,2005,29(3)：132-136.
[6]Jorgensen TJ, Helzlsouer KJ, Clipp SC, et al. DNA repair gene variants associated with benign breast disease in high cancer risk women. Cancer Epidemiol Biomarkers Prev,2009,18(1):346-350.
[7]Loizidou MA, Michael T, Neuhausen SL, et al. Genetic polymorphisms in the DNA repair genes XRCC1, XRCC2 and XRCC3 and risk of breast cancer in Cyprus. Breast Cancer Res Treat,2008,112(3):575-579.
[8]Zienolddiny S, Campa D, Lind H, et al. Polymorphisms of DNA repair genes and risk of non-small cell lung cancer. Carcinogenesis,2006,27(3):560-567.
[9]Yen CY, Liu SY, Chen CH, et al. Combinational polymorphisms of four DNA repair genes XRCC1, XRCC2, XRCC3, and XRCC4 and their association with oral cancer in Taiwan. J Oral Pathol Med,2008,37(5):271-277.
[10]Moreno V, Gemignani F, Landi S, et al. Polymorphisms in genes of nucleotide and base excision repair:risk and prognosis of colorectal cancer. Clin Cancer Res, 2006,12(7 Pt1):2101-2108.
[11]Matullo G, Guarrera S, Sacerdote C, et al. Polymorphisms/haplotypes in DNA repair genes and smoking:a bladder cancer case-control study. Cancer Epidemiol Biomarkers Prev,2005,14(11 Pt 1):2569-2578.
[12]Romanowicz-Makowska H, Smolarz B, Zadrozny M, et al. The association between polymorphisms of the RAD51-G135C, XRCC2-Arg188His and XRCC3-Thr241Met genes and clinico-pathologic features in breast cancer in Poland. Eur J Gynaecol Oncol,2012,33(2):145-150.
[13]Lin WY, Camp NJ, Cannon-Albright LA, et al. A role for XRCC2 gene polymorphisms in breast cancer risk and survival. J Med Genet,2011,48(7): 477-484.
[14]Yu KD, Chen AX, Qiu LX, et al. XRCC2 Arg188His polymorphism is not directly associated with breast cancer risk:evidence from 37,369 subjects. Breast Cancer Res Treat,2010,123(1):219-225.
[15]Pooley KA, Baynes C, Driver KE, et al. Common single-nucleotide polymorphisms in DNA double-strand break repair genes and breast cancer risk. Cancer Epidemiol Biomarkers Prev,2008,17(12):3482-3489.
[16]Curtin K, Lin WY, George R, et al. Genetic variants in XRCC2:new insights into colorectal cancer tumorigenesis. Cancer Epidemiol Biomarkers Prev,2009,18(9): 2476-2484.
[17]Krupa R, Sliwinski T, Wisniewska-Jarosinska M, et al. Polymorphisms in RAD51, XRCC2 and XRCC3 genes of the homologous recombination repair in colorectal cancer--a case control study. Mol Biol Rep,2011,38(4):2849-2854.
[18]Jiao L, Hassan MM, Bondy ML, et al. XRCC2 and XRCC3 gene polymorphism and risk of pancreatic cancer. Am J Gastroenterol,2008,103(2):360-367.
[19]Li D, Liu H, Jiao L, et al. Significant effect of homologous recombination DNA repair gene polymorphisms on pancreatic cancer survival. Cancer Res,2006,66(6): 3323-3330.
[20]Wang R, Wang W, Zhang JW. Correlation between XRCC2 and XRCC5 single nucleotide polymorphisms and drug-sensitivity of human lung cancer cells. Zhonghua Yi Xue Za Zhi,2008,88(43):3059-3062.
[21]Bastos HN, Antao MR, Silva SN, et al. Association of polymorphisms in genes of the homologous recombination DNA repair pathway and thyroid cancer risk. Thyroid, 2009,19(10):1067-1075.
[22]Webb PM, Hopper JL, Newman B, et al. Double-strand break repair gene polymorphisms and risk of breast or ovarian cancer. Cancer Epidemiol Biomarkers Prev,2005,14(2):319-323.
[23]Jakubowska A, Gronwald J, Menkiszak J, et al. The RAD51135 G>C polymorphism modifies breast cancer and ovarian cancer risk in Polish BRCA1 mutation carriers. Cancer Epidemiol Biomarkers Prev,2007,16(2):270-275.
[24]Krupa R, Sliwinski T, Wisniewska-Jarosinska M, et al. Polymorphisms in RAD51, XRCC2 and XRCC3 genes of the homologous recombination repair in colorectal cancer-a case control study. Mol Biol Rep,2011,38(4):2849-2854.
[25]Wisniewska-Jarosinska M, Sliwinfski T, Krupa R, et al. The role of Rad51 gene polymorphism in patients with colorectal cancer in the Polish subpopulation. Pol Merkur Lekarski,2009,26(155):455-457.