黄芩苷对错配修复基因缺失LoVo细胞的抑制作用及其机制

目的:探讨黄芩苷诱导LoVo细胞凋亡的作用及机制.方法:将黄岑苷40 mg溶于19.8 mL生理盐水 100 μL HCI 100 μL NaOH,阿斯匹林1.8 g溶于2 mL乙腈 4 mLNaOH 2 mLHCl,分别处理LoVo细胞,1 g/L乙腈溶液为对照.采用体外培养技术、TUNEL法观察细胞凋亡率,变性凝胶电泳检测微卫星标志BAT-25、D2S123状况.结果:黄芩苷和阿斯匹林均能诱导LoVo细胞凋亡,在各时间点与对照组比较统计学差异有显著意义(P=0.0000);黄芩对结肠LoVo细胞的诱导凋亡作用明显强于阿司匹林,24 h两差异无统计学意义,96 h和1 wk两者差异统计学有显著意义(93.33％ vs 44.23％,63.29％ vs23.20％,均P=0.0000),其作用时间在96 h达到高峰,与时间不呈依赖关系.黄芩苷和阿司匹林均未影响LoVo细胞的BAT-25、D2S123微卫星状态.结论:黄芩苷具有较强诱导LoVo细胞凋亡的作用.但对LoVo细胞的BAT-25、D2S123微卫星状态无影响,其诱导LoVo细胞凋亡可能是通过其它作用途径.     

中药抗结直肠癌作用的研究进展

大肠癌是常见的消化系恶性肿瘤之一,其发病率在我国呈逐年上升趋势.近年来,中药治疗大肠癌已受到研究者的关注.研究发现,中药具有抗结肠癌的作用,主要通过抑制肿瘤细胞增殖、促进细胞凋亡、抑制端粒酶活性、阻滞细胞周期进展、抑制结肠癌血管内皮生长因子形成、诱导结肠癌细胞自噬、抑制结肠癌细胞迁移等多种途径.本文就中药抗大肠癌的作用机制、实验研究及临床应用进行综述.     

凋亡素基因对人结肠癌细胞作用的研究

目的探讨凋亡素基因的导人对人结肠癌细胞的影响。方法将凋亡素基因VP3克隆人真核表达载体pEGFP-C2，构建成重组质粒pEGFP-VP3。用脂质体转染法将pEGFP-C2和pEGFP—VP3分组分别转染人类结肠癌细胞（Lovo）和小鼠胚胎成纤维细胞（NIH3T3），通过荧光显微镜观察绿色荧光蛋白在不同组细胞中的定位、表达及细胞的生长、凋亡情况，MTT法测定不同组细胞的生长曲线，并用AnnexinV—FITC流式细胞技术检测细胞的凋亡率。结果在Lovo／EGFP组和3T3／EGFP—VP3组细胞中，EGFP均匀分布于细胞中，细胞形态无明显变化，细胞凋亡率较非转染细胞组亦无明显增加。而在Lovo／EGFP-VP3组细胞中，EGFP-VP3以荧光颗粒形式集中在细胞核，并逐渐变粗，最后细胞碎裂成片状，流式细胞技术检测Lov0／EGFP-VP3组的细胞凋亡率明显高于其他对照组（P〈0．01）。结论pEGFP-VP3可诱导人类结肠癌细胞凋亡。     

U6嵌和型Maxizyme对肝癌突变抑癌基因p53的抑制作用

目的探讨U6嵌和型Maxizyme对肝癌突变抑癌基因p53的抑制作用。方法应用计算机设计针对肝癌突变抑癌基因p53(mtp53)249位密码子(AGG→AGT)Maxizyme(Mz)的基因片段,构建其真核表达载体,使抗mtp53的Mz嵌于U6表达系统中,细胞外由T7 RNA聚合酶转录,细胞内由RNA聚合酶Ⅲ高效转录。检测Mz在细胞外对mtp53的切割效率。在LipofectamineTM2000介导下转染肝癌细胞MHCC97,应用逆转录聚合酶链反应(RT-PCR)检测Mz对肝癌细胞mtp53的抑制作用,western blot分析mtp53蛋白表达水平,并用四甲基偶氮唑盐(MTT)法观察肿瘤细胞的生长情况。结果在细胞外,Mz可特异性切割靶基因mtp53,切割效率为42%,而野生型p53(wtp53)没有被切割。RT-PCR和western blot检测结果提示转染Mz的MHCC97内mtp53 mRNA和蛋白(5.3 ×104)表达均明显下降,转染Mz的MHCC97增殖速度明显降低。结论U6表达系统能高效启动核酶等小分子RNA的转录,U6嵌和型Maxizyme在细胞内外均可特异性抑制mtp53表达,抑制肝癌细胞增殖,有望开发为肝癌基因治疗的新方法。     

VEGF反义寡核苷酸对体外生长的大肠癌HT-29细胞的抑制作用

目的:探讨血管内皮生长因子(VEGF)反义寡核苷酸(ASODN)对体外生长的人大肠癌HT-29细胞的抑制作用.方法:实验设空白对照组、脂质体转染组、错义链转染组(SODN组)和不同浓度反义链转染组(ASODN组).用LipofectamineTM2000介导的VEGF ASODN和错义寡核苷酸(SODN)转染人大肠癌细胞株HT-29,半定量RT-PCR检测各组细胞VEGF mRNA的表达:Western blot测定转染48、72 h后VEGF蛋白表达:MTT法和流式细胞术检测细胞增殖和凋亡.结果:转染48 h后,ASOND组的VEGF mRNA表达水平明显低于脂质体对照组和SODN组(0.455±0.032 vs 0.934±0.031,0.915±0.004,p<0.01);脂质体对照组与SODN组之间无显著差异.细胞转染48、72 h后,ASODN组蛋白表达明显弱于脂质体对照组和SODN组,且72h弱于48 h.与对照组比较.VEGF ASODN对HT-29细胞有明显的生长抑制作用,并且抑制呈剂量和时间依赖性(P<0.05).结论:VEGF ASODN通过抑制VEGF的基因表达,对体外生长的人大肠癌HT-29细胞的增殖进行抑制.     

反义RNA对胃癌细胞MT1-MMP基因表达和侵袭性的抑制作用

目的:膜研究膜型-1基质金属蛋白酶(MT1- MMP)反义RNA对人胃癌细胞BGC823靶基因表达和侵袭特性的影响方法:利用基因重组技术构建人MT1-MMP反义RNA真核表达载体,转染人胃癌细胞BGC823,应用RT-PCR、MTT、明胶酶谱和体外侵袭实验等方法观察人胃癌细胞BGC823转染前后,MT1-MMP mRNA表达水平、细胞生长、明教酶A活性及细胞体外侵袭能力等指标的变化.结果:成功构建了MT1-MMP反义RNA真核表达载体pasMMP14,将其转染胃癌细胞BGC823后,与阴性对照组相比,实验组MT1- MMP mRNA表达水平降低,抑制率为36%.转染48 h,明教酶A的活化受到了明显抑制.转染72 h,细胞增殖明显受抑(t=2.358,P<0.01 vs空白组:t=2.727 P<0.01 vs阴性组).实验组的穿膜细胞数明显低于空白对照组和阴性对照组(t=5.744,P<0.01;t=5.695,P<0.01).结论:反义RNA对人胃癌细胞MT1-MMP基因表达和侵袭能力具有明显的抑制作用,MT1-MMP基因可作为胃癌抗侵袭治疗的分子靶点.     

PAF对肠上皮细胞紧密连接的影响及ITF的保护作用

目的:探讨血小板活化因子(PAF)是否会引起肠黏膜屏障的破坏以及这种破坏机制是否与紧密连接相关,并观察肠三叶因子(ITF)的保护作用.方法:培养人结肠腺癌细胞株caco-2,分别设正常对照组:不加刺激物及干预因素;实验组:加入PAF,终浓度分别为50 ng/L、100 ng/L和200 ng/L;ITF预防组:先加入ITF0.3 g/L,30 min后加入PAF 100 ng/L;ITF治疗组:先加入PAF 100 ng/L,30 min后加入ITF0.3 g/L,24 h后进行实验.MTT比色法检测细胞活力;测定跨上皮电阻TER和荧光黄的透过量反映肠上皮细胞单层通透性:RT-PCR法检测紧密连接蛋白ZO-1和Occludin mRNA表达的变化;免疫荧光染色观察紧密连接蛋白ZO-1和Occludin的形态学.结果:PAF未影响到细胞的增殖和细胞活力.各浓度PAF作用24 h后,细胞单层通透性增加,跨上皮电阻(TER)下降,荧光黄透过增加.ITF治疗组及预防组TER下降值较模型组明显降低(122.2±14.7,100.3±10.9 vs 210.3±26.4,P＜0.05),荧光黄透过量减少(10226.1±556.2,9711.2±364.9 vs 11601.2±693.5,P＜0.05),预防组作用更明显.PAJF作用后,ZO-1和Occludin mRNA表达均有下降,以100 ng/L组改变最为明显.ITF预防组较之表达增加(1.28±0.06 vs 1.07±0.05,1.13±0.07 vs 0.81±0.06,P＜0.05),ITF治疗组改变不明显.免疫荧光染色发现ZO-1和Occludin主要分布在细胞内近胞膜处.PAF作用后,ZO-1及Occludin形态学改变,预防性给予ITF后,可明显减轻这种改变.结论:PAF可引起肠黏膜屏障破坏,其机制可能和紧密连接蛋白的破坏相关;ITF可以通过改变紧密连接蛋白的表达而部分恢复肠黏膜正常通透性,起到保护作用.     

控制正常细胞对肺癌细胞P~(16)基因缺失的污染的方法的建立及其应用

目的建立一种能有效提高从混有正常细胞的肿瘤组织中检测Ｐ１６基因纯合缺失的灵敏度的方法，以及探讨该基因的状态与肺癌临床病理的关系。方法将野生型ＤＮＡ与Ｐ１６基因纯合缺失的ＤＮＡ按一定比例混合，并将其有限稀释，以不同量的ＤＮＡ为模板，用聚合酶链反应（ＰＣＲ）扩增Ｐ１６基因第二外显子及内对照基因片断，在此基础上，以特定量肺癌ＤＮＡ为模板，用相同的ＰＣＲ条件对上述片断进行扩增，对扩增出的第二外显子行单链构型多态性（ＳＳＣＰ）分析。结果ＤＮＡ模板为５ｎｇ，野生型ＤＮＡ不超过总ＤＮＡ４０％时，不掩盖Ｐ１６基因纯合缺失。小细胞肺癌，癌旁肺无Ｐ１６基因纯合缺失及突变，５２例非小细胞肺癌中有２１例Ｐ１６基因纯合缺失，３例第二外显子ＳＳＣＰ异常，其中伴淋巴结转移的非小细胞肺癌Ｐ１６基因的纯合缺失率（７２％）显著高于无淋巴结转移者（１６．６％）。同时还发现Ｐ１６基因的异常与非小细胞肺癌的临床病理分级及预后明显相关。Ｐ１６基因缺失的患者术后存活时间显著低于无Ｐ１６基因缺失者。结论控制ＰＣＲ中模板的量有助于提高检测Ｐ１６基因缺失的灵敏度。Ｐ１６基因异常可能参与非小细胞肺癌的恶性进展。     

FasL基因转染诱导类风湿关节炎患者滑膜细胞凋亡的实验研究

目的通过构建FasL重组质粒并转染原代培养的类风湿关节炎(RA)患者滑膜细胞,研究FasL基因对体外培养的RA滑膜细胞的凋亡诱导作用,寻找针对RA关节腔内基因治疗的有效靶基因.方法采用反转录-聚合酶链反应(RT-PCR)方法扩增FasL cDNA全长片段,经BamH Ⅰ和Xho Ⅰ双酶切,将FasL基因导入真核表达载体pcDNA3.1-neo;体外原代培养RA患者及正常人的滑膜细胞:脂质体包裹真核表达质粒pcDNA3.1-FasL及空质粒pcDNA3.1-neo,分别转染处于指数生长期的RA患者及正常人的滑膜细胞;经G418筛选,采用形态学、TUNEL法及Annexin Ⅴ/碘化丙啶(PI)染色等方法检测各组滑膜细胞的凋亡情况.结果FasL基因原核及真核重组质粒载体顺利构建,基因序列检测结果与国外报道完全一致;RA患者及正常人的滑膜细胞原代培养、传代顺利完成;RA患者滑膜细胞转染FasL重组质粒(rhFasL)15 h后,光镜下可见大量细胞体积缩小、扭曲、变形,胞核中出现颗粒样物质,少数细胞脱落底壁,G418筛选2周后仅有1～2个/低倍视野细胞存活,且生长相对静止;RA患者滑膜细胞在转染空质粒及正常人滑膜细胞在转染pcDNA3.1-FasL及空质粒后仅有少数细胞变形、反光度下降,很少脱离底壁,G41 8筛选2～4周后细胞再次生长并形成克隆;经TUNEL方法检测可见大量转染rhFasL的RA滑膜细胞的细胞核呈棕黄或棕褐色,胞核浓缩,呈环行、小圆形或颗粒状,而其他3组对照组滑膜细胞的细胞核呈蓝色或浅黄色,未见明显凋亡标记阳性细胞;基因转染后的各组滑膜细胞予Annexin Ⅴ/PI染色、流式细胞仪检测后均查到少量早期的凋亡细胞,但各组间差异无统计学意义.结论pcDNA3.1-FasL基因可诱导体外培养的RA滑膜细胞间的凋亡增加.     

载脂蛋白A4基因多态性对中药降血脂的影响

目的探讨载脂蛋白（Apo）A4基因多态性与芪参益气滴丸治疗气虚血瘀型冠心病疗效的关系。方法气虚血瘀型冠心病患者49例,门诊服用芪参益气滴丸1个月,治疗前后各抽取血样一次,测定血脂含量并提取外周血白细胞DNA,PCR扩增ApoA4基因第3外显子,测序检测多态性位点。结果在ApoA4基因的第3外显子中发现1个有义突变位点,第917位碱基C→T的突变,减弱了药物对LDL的降低作用,在非突变组比突变组之间达到极显著差异（P=0.009）。结论ApoA4基因C917T多态性对芪参益气滴丸降低低密度脂蛋白（LDL）有显著影响。     

Clinical and molecular analysis of hereditary non-polyposis colorectal cancer in Chinese colorectal cancer patients

AIM:To analyze the frequency of hereditary non-polyposis colorectal cancer(HNPCC)in Chinese colorectal cancer(CRC)patients,and to discuss the value of microsatellite instability(MSI)and/or immunohistochemistry(IHC)for MSH2/MLH1 protein analysis as pre-screening tests in China.METHODS:The Amsterdam criteriaⅠandⅡ(clinical diagnosis)and/or germline hMLH1/hMSH2 mutations(genetic diagnosis)were used to classify HNPCC families.Genetic tests,including microsatellite instability,immunohistochemistry for MSH2/MLH1 proteins and hMSH2/hMLH1 genes,were performed in each proband.RESULTS:From July 2000 to June 2004,1988 patients with colorectal cancer were analysed and 114 CRC patients(5.7%)from 48 families were categorized as having HNPCC,including 76 from 26 families diagnosed clinically and 38 from the other 22 families diagnosed genetically.The sensitivity and specificity of high MSI and IHC for predicting mutations were 100% and 54%,and 79% and 77%,respectively.CONCLUSION:The frequency of HNPCC is approximately 10% among all Chinese CRC cases.The MSI and IHC detections for hMSH2/hMLH1 proteins are reliable pre-screening tests for hMLH1/hMSH2 germline mutations in families suspected of having HNPCC.     

k-ras基因在中国结直肠癌患者中的突变状态

目的:评价中国结直肠癌患者中K-ras基因突变状态及其与临床病理参数的关系.方法:收集2008-01/2009-12在中国人民解放军南京军区福州总医院手术切除的临床资料完整的结直肠癌石蜡包埋组织280例,分别应用实时荧光定量PCR和直接测序法检测结直肠癌中K-ras基因外显子2中第12、13编码子上最常见的7种突变类型...     

Detection of telomerase activity in biopsy samples of colorectal cancer

BACKGROUND: Telomerase is a ribonucleoprotein that synthesizes telomeric DNA onto chromosomal ends. The expression of telomerase is thought to be required for cellular immortality and oncogenesis. METHODS: To investigate the role of telomerase in the pathogenesis of colorectal cancer, we analysed telomerase activity in biopsy samples of colorectal cancer and colonic adenomas. Using a polymerase chain reaction-based assay, we examined telomerase activity in 52 samples of colorectal cancer, 12 colonic adenomas and 30 normal colonic mucosa samples obtained by endoscopic biopsy. RESULTS: Telomerase activity was detectable in 88.5% (46/52) of colorectal carcinomas, in 50% (6/12) of colonic adenomas but not in normal colorectal mucosa. There was no correlation between telomerase activity and tumour location, type, size and differentiation (P > 0.05). CONCLUSIONS: It was concluded that telomerase activation plays a role in the evolution of colorectal cancer, and that measurement of telomerase activity in biopsied colorectal mucosa samples may provide information both as a diagnostic marker to detect small numbers of cancer cells, and as a screening method for patients at high risk for colorectal carcinoma.     

Decreased expression of miR-133a correlates with poor prognosis in colorectal cancer patients

AIM: To investigate microRNA-133a (miR-133a) expression in colorectal cancer (CRC) and its relationship with tumorigenesis and disease prognosis.METHODS: Quantitative real-time polymerase chain reaction was used to measure levels of miR-133a in tumor samples and adjacent non-cancerous tissues from 169 patients undergoing radical resection for CRC. The associations between miR-133a expression and patient age, sex, as well as clinicopathologic parameters, such as tumor size, differentiation, location, invasion depth, metastasis, tumor-node-metastasis (TNM) stage and overall patient survival, were analyzed by Mann-Whitney U and Kruskal-Wallis tests. The Kaplan-Meier method and Cox proportional hazards regression analyses were performed to estimate the prognostic factors for patient survival prediction.RESULTS: The expression of miR-133a was significantly downregulated in CRC tissues compared with adjacent non-cancerous tissues (P < 0.05). This reduction was associated with the depth of the local invasion, poor differentiation, lymph node metastasis and advanced disease (P < 0.05). Moreover, Kaplan-Meier analysis demonstrated that patients with low miR-133a expression had poorer overall survival (OS) than those with high miR-133a expression (P < 0.001). Univariate analysis revealed statistically significant correlations between OS and miR-133a level, tumor local invasion, lymph node metastasis and TNM stage (P < 0.001). Furthermore, miR-133a levels and TNM stage were independently associated with OS (HR = 0.590, 95%CI: 0.350-0.995, P < 0.05; and HR = 6.111, 95%CI: 1.029-36.278, P < 0.05, respectively).CONCLUSION: The downregulation of miR-133a may play an important role in the progression of CRC and can be used as an independent factor to determine CRC prognosis.     

人结直肠癌微小核糖核酸的差异表达及其临床意义

目的:研究人结直肠癌、腺瘤和癌旁正常组织中微小核糖核酸(microRNAs,miRNAs)的差异表达谱,并初步探讨其临床意义.方法:选取2008-01/07苏州大学附属第一医院和泰州市人民医院结直肠癌、对应癌旁正常组织以及结直肠腺瘤标本,提取组织总RNA,采用illumina microRNA芯片技术检测3种不同类型组织中miRNAs的表达,采用实时定量PCR技术对芯片检测结果进行验证.将结直肠癌组织中异常表达的miRNAs与结直肠癌患者的临床病理资料进行分析.结果:3种不同类型结直肠组织中miRNAs表达有明显差异,结直肠癌与癌旁正常组织相比,有65个miRNAs表达异常(P<0.001),其中35个上调,30个下调,而腺瘤与正常结直肠组织相比,有55个miRNAs表达差异(P<0.001),其中上调29个,下调26个.有25个miRNAs相对于正常组织同时在结直肠癌和腺瘤中异常表达,其中高表达12个,低表达有13个.与腺瘤相比,结直肠癌中有25个miRNAs表达异常(P<0.01),其中13个上调,12个下调.进一步定量PCR验证结果显示与正常结直肠黏膜组织相比,在癌组织中miR-552,miR-142-...     

氧化苦参碱对人胃癌细胞杀伤作用的机制

目的:探讨氧化苦参碱(oxymatrine,OM)对人胃癌细胞株MKN45的杀伤作用及其抗肿瘤作用的机制.方法:培养人胃癌MKN45细胞,以0.5,1,2,4,6 g/L OM处理.采用四唑蓝(MTT)比色法、流式细胞仪、聚合酶链反应(PCR),酶联免疫吸附测定(ELISA)和RT-PCR法检测OM对MKN45细胞的杀伤作用、细胞周期分布、端粒酶活性和端粒酶逆转录酶(hTERT)及其上游调控基因(c-myc,p53,mad1)表达的影响.结果:OM对MKN45细胞具有剂量依赖性杀伤作用,半数抑制浓度(IC_(50))78 g/L.OM作用48 h后,与对照组相比,在2 g/L剂量组,MKN45 G0/G1期细胞增加(62.2%±1.3% vs 56.7%±4.0%,P<0.05)、G2/M期细胞减少(5.4%±1.1% vs 10.0%±2.8%,P<0.05);在4 g/L剂量组,S期细胞减少(30.5%±1.3% vs 33.4%±1.2%,P<0.05).OM可抑制MKN45细胞的端粒酶活性,其作用呈剂量依赖性.OM可引起MKN45细胞hTERT基因表达下调,p53和mad1基因的表达升高,对c-myc基因的表达无影响.结论:OM对人胃癌细胞株MKN45具有杀伤作用,可能通过影响hTERT及其上游调控基因的表达来抑制肿瘤细胞端粒酶活性,发挥其抗肿瘤作用.     

结直肠癌组织中ECM1基因水平的测定及临床意义

目的:探讨细胞外基质蛋白1基因在结直肠癌中的表达及其意义.方法:基于TaqMan-MGB荧光探针技术,建立实时荧光定量RT-PCR方法,检测正常结直肠黏膜组织(n=46),结直肠腺瘤(n=18),结直肠癌(淋巴结未转移)(n=25)和结直肠癌(淋巴结转移)(n=21)中ECM1基因的表达.结果:正常黏膜,腺瘤组织,结直肠癌(淋巴结未转移)组织和结直肠癌(淋巴结转移)组织中ECM1基因的表达均值分别为(9.81±3.16)×10~8拷贝/g RNA,(10.1±3.65)×10~8拷贝/g RNA,(6.89±2.96)×10~9拷贝/g RNA,(5.01±2.22)×10~(10)拷贝/g RNA.正常黏膜和腺瘤组织组间无明显差异(P>0.05);结直肠癌(淋巴结未转移)组明显高于正常黏膜和腺瘤组织组P<0.01);结直肠癌(淋巴结转移)组明显高于其他三组(P<0.01).结论:ECM1基因在结直肠癌中表达升高,并且与结直肠癌的转移相关.     

大肠癌患者外周血人类斯钙素基因的检及其意义

目的探讨靶基因人类斯钙素(hSTC-1)在大肠癌患者外周血中的表达以及与肿瘤恶性程度的关系.方法采用RT-PCR方法检测15例健康成人、5例妊娠期妇女、14例消化道炎症疾病患者、57例大肠癌患者外周血的hSTC-1 mRNA.结果57例大肠癌患者外周血中hSTC-1 mRNA的阳性率为49.12%(28/57),并与大肠癌的临床分期有显著相关性(P＜0.05).而健康成人、妊娠期妇女、消化道炎症疾病患者外周血则无一例出现阳性.结论应用RT-PCR方法检测大肠癌患者外周血中的hSTC-1 mRNA具有高度敏感性和特异性,它有望成为判断大肠癌生物学行为恶性程度、转移和复发以及疗效观察的客观指标.     

Association of Fusobacterium nucleatum infection with colorectal cancer in Chinese patients

AIM: To investigate Fusobacterium nucleatum(F. nucleatum) abundance in colorectal cancer(CRC) tissues and its association with CRC invasiveness in Chinese patients.METHODS: The resected cancer and adjacent normal tissues(10 cm beyond cancer margins) from 101 consecutive patients with CRC were collected. Fluorescent quantitative polymerase chain reaction(FQ-PCR) was applied to detect F. nucleatum in CRC and normal tissues. The difference of F. nucleatum abundance between cancer and normal tissues and the relationship of F. nucleatum abundance with clinical variables were evaluated. Fluorescence in situ hybridization(FISH) analysis was performed on 22 CRC tissues with the highest F. nucleatum abundance by FQ-PCR testing to confirm FQ-PCR results.RESULTS: The median abundance of F. nucleatum in CRC tissues [0.242(0.178-0.276)] was significantly higher than that in normal controls [0.050(0.023-0.067)](P 0.001). F. nucleatum was over-represented in 88/101(87.1%) CRC samples. The abundance of F. nucleatum determined by 2~(-ΔCT) was significantly greater in tumor samples [0.242(0.178, 0.276)] than in normal controls [0.050(0.023, 0.067)](P 0.001). The frequency of patients with lymph node metastases was higher in the over-abundance group [52/88(59.1%)] than in the under-abundance group [0/13(0%)](P 0.005). No significant association of F. nucleatum with other clinico-pathological variables was observed(P 0.05). FISH analysis also found more F. nucleatum in CRC than in normal tissues(median number 6, 25~(th) 3, 75~(th) 10 vs 2, 25~(th) 1, 75~(th) 5)(P 0.01).CONCLUSION: F. nucleatum was enriched in CRC tissues and associated with CRC development and metastasis.