去氢骆驼蓬碱诱导HepG2细胞凋亡并增强其对5-氟尿嘧啶和顺铂的敏感性

 目的:研究去氢骆驼蓬碱体外诱导HepG2细胞凋亡过程中c-Jun N末端激酶（JNK）途径的作用,并观察其联合化疗药物对HepG2细胞的影响。方法:CCK-8法检测联合或不联合使用JNK特异性抑制剂SP600125对细胞增殖的抑制作用;克隆形成实验观察不同浓度药物对细胞克隆形成的影响;Hoechst 33258染色法观察细胞形态变化;PI单染检测细胞亚二倍体率;Annexin V-PI双染测定细胞早期凋亡水平;Western blotting检测细胞聚（ADP-核糖）聚合酶（PARP）、JNK和p-JNK蛋白表达的改变;联合5-氟尿嘧啶（5-FU）或顺铂(DDP)观察细胞对化疗药物的敏感性。结果:去氢骆驼蓬碱随药物浓度的升高而抑制作用增强,48 h后IC50为9.80 mg/L;去氢骆驼蓬碱能显著抑制细胞克隆形成,并且导致细胞凋亡形态学变化;PI单染检测发现细胞周期的G1期前有亚二倍体凋亡峰,Annexin V-PI 双染检测细胞出现明显的早期凋亡细胞群;Western blotting检测到随着去氢骆驼蓬碱浓度增加PARP及p-JNK蛋白表达增加,JNK蛋白表达减少;联合使用SP600125对细胞增殖的抑制作用减弱;联合5-FU或顺铂明显增强化疗药物对肿瘤细胞的抑制作用,增敏倍数分别为1.47和5.78倍。结论: 去氢骆驼蓬碱对HepG2细胞有增殖抑制作用,并诱导其凋亡,激活JNK信号通路可能是其主要机制之一;同时去氢骆驼蓬碱可以增强HepG2细胞对5-FU和顺铂的敏感性。     

MicroRNA-98通过下调EZH2表达抑制结直肠癌细胞的活力与侵袭能力

目的:探讨微小RNA-98(mi R-98)与Zeste基因增强子同源物2(EZH2)之间的靶向关系,及其对结直肠癌细胞活力和侵袭能力的影响。方法:Target Scan软件预测EZH2和mi R-98之间的靶向结合,双萤光素酶报告基因实验验证mi R-98与EZH2之间的靶向关系。用mi R-98 mimic和mi R-98 inhibitor分别转染人结直肠癌SW480细胞和SW620细胞,Western blot检测EZH2的蛋白表达; MMT法检测细胞活力; Transwell法检测细胞的侵袭能力。转染EZH2过表达质粒检测其对细胞活力和侵袭的影响。结果:mi R-98能够靶向调节EZH2并负向调节SW480细胞和SW620细胞中EZH2的蛋白表达。在SW480细胞和SW620细胞中,过表达mi R-98显著下调细胞活力和侵袭能力,而抑制mi R-98表达显著促进细胞生长和侵袭。过表达EZH2也可促进SW480细胞和SW620细胞的生长和侵袭。结论:mi R-98通过下调EZH2表达抑制SW480细胞和SW620细胞的活力和侵袭。本研究为结直肠癌的治疗提供了新的靶点和方向。     

敲减NOB1基因表达对人结肠癌SW480细胞药物敏感性及侵袭和迁移能力的影响

目的:探讨通过小干扰RNA(small interfering RNA, siRNA)技术敲减NOB1基因表达对人结肠癌SW480细胞活力、药物敏感性、凋亡、细胞周期及侵袭和迁移能力的影响。方法:利用脂质体Lipofectamine 3000将NOB1 siRNA转染至SW480细胞,采用real-time PCR和Western blot检测转染后SW480细胞中NOB1 mRNA和蛋白表达的变化;采用MTT法检测敲减NOB1基因表达后SW480细胞活力及其对不同化疗药物(顺铂、5-氟尿嘧啶、奥沙利铂和卡培他滨)敏感性的变化;流式细胞术检测敲减NOB1基因表达对SW480细胞凋亡和周期的影响;Transwell方法检测敲减NOB1基因表达对结肠癌SW480细胞侵袭和迁移能力的影响。结果:转染NOB1 siRNA后,SW480细胞中NOB1的mRNA和蛋白表达水平明显降低(P0.05);与对照组和阴性对照siRNA组相比,NOB1 siRNA转染组的SW480细胞在24～72 h的细胞活力显著降低,顺铂、5-氟尿嘧啶、奥沙利铂和卡培他滨对该细胞的半数抑制浓度均显著降低,细胞凋亡率显著增加,细胞周期受到阻滞,细胞侵袭和迁移能力显著降低(P0.05)。结论:NOB1 siRNA转染能够抑制结肠癌SW480细胞活力及侵袭和转移能力,并增强细胞对药物的敏感性,促进细胞凋亡。NOB1能够成为结肠癌诊断和治疗的新靶点。     

Studies on anti-metastatic and anti-invasive effects of harmine using highly metastatic murine B16F-10 melanoma cells

Harmine is a beta-carboline alkaloid from the plant Peganum harmala. We evaluated the anti-metastatic activity of harmine using in vivo mouse lung metastasis and in vitro models. Lung metastasis was induced using B16F-10 melanoma cells in C57BL/6 mice by three different modalities of administration: simultaneous, prophylactic, and after tumor development. Harmine significantly inhibited tumor nodule formation in the lung tissue and decreased various biochemical parameters associated with lung metastasis. Higher expression levels of pro-metastatic genes such as matrix metalloproteinase-9 (MMP-9), extracellular signal[en]regulated kinase (ERK), and vascular endothelial factors (VEGFs), all of which play important roles in cancer cell migration and invasion, were observed in the metastatic group compared with normal, but were all down-regulated by treatment with harmine. Harmine was also able to inhibit tumor cell proliferation, invasion, and migration in vitro. In conclusion, harmine exerts anti-metastatic activity and this effect could be linked to the metastasis-related signaling pathway that includes ERK, VEGF, and MMPs.     

miR-23a和ESRP1在直肠癌中的作用

目的:研究miR-23a和上皮剪接调节蛋白1(epithelial splicing regulatory protein 1,ESRP1)在直肠癌组织及细胞系中的表达,以及对体外直肠癌细胞活力和凋亡的作用。方法:采用RT-q PCR分析miR-23a在36例直肠癌组织和癌旁组织中的表达,免疫组化检测ESRP1在直肠癌组织中的表达,分析miR-23a和ESRPl在直肠癌组织中的相关性;利用RT-q PCR检测miR-23a在直肠癌Caco-2和SW480细胞及人正常结肠上皮细胞株NCM460中的表达;合成miR-23a inhibitor和inhibitor阴性对照(inhibitor NC),并将其分别转染至SW480细胞后,通过CCK-8法检测miR-23a inhibitor转染SW480细胞后对细胞活力的影响,流式细胞术检测转染后细胞凋亡率,Transwell小室实验检测细胞侵袭;通过Western blot技术检测SW480细胞中ESRPl蛋白的表达;构建野生型pGL3-ESRP1-3’UTR(wt-pGL3-ESRP1-3’UTR)或突变型pGL3-ESRP1-3’UTR(mut-pGL3-ESRP1-3’UTR)质粒,并分别与miR-23a inhibitor或inhibitor NC共转染至HEK293和SW480细胞中,利用双萤光素酶报告基因检测试剂盒说明检测双萤光素酶活性;将ESRP1 mimic或mimic NC瞬时转染SW480细胞后,CCK-8法和流式细胞术分别检测细胞活力和凋亡;Western blot法检测瞬转ESRP1 mimic后对ESRP1、caspase-3、Smac和XIAP蛋白表达的影响。结果:miR-23a和ESRP1在直肠癌组织的表达较癌旁正常组织分别上调和下调,两者呈明显负相关(P0.01);miR-23a的表达与直肠癌的淋巴结转移和肿瘤浸润深度相关;与NCM460细胞相比较,miR-23a在SW480细胞中的表达量显著上调(P0.01);转染miR-23a inhibitor后,SW480细胞活力较inhibitor NC组显著下降(P0.01);转染miR-23a inhibitor后SW480细胞早期凋亡率明显升高,同时细胞体外侵袭能力受到抑制;萤光素酶报告基因结果表明ESRP1是miR-23a的直接靶基因;转染miR-23a inhibitor至SW480细胞后ESRP1蛋白表达水平明显升高;ESRP1 mimic转染SW480细胞后可抑制细胞活力并诱导细胞凋亡,同时上调caspase-3和Smac的表达,下调XIAP的表达。结论:miR-23a可通过负向调控下游靶基因ESRP1从而影响直肠癌细胞生长和凋亡。     

Harmine activates intrinsic and extrinsic pathways of apoptosis in B16F-10 melanoma

Background  

Harmine is a beta-carboline alkaloid from the plant Peganum harmala. Previous studies found that harmine inhibited metastasis of B16F-10 melanoma cells. This study aims to elucidate the role of harmine in apoptosis of B16F-10 cells.     

非甾体类抗炎药对结肠癌细胞NAG-1 基因表达的诱导

研究非甾体类抗炎药(Non-steroidal anti-inflammatory drug,NSAID)对结肠癌细胞生长的影响及NSAID活化基因-1(NAG-1)的诱导作用。体外培养HT-29、SW480及LS174-T三种结肠癌细胞,分别加入不同浓度的aspirin、celecoxib及meloxicam作用于HT-29及SW480细胞,采用MTT法检测结肠癌细胞增殖;蛋白质印迹技术检测三种结肠癌细胞COX-2的表达;采用半定量RT-PCR技术分析NSAID对三种结肠癌细胞NAG-1基因表达的影响。aspirin、celecoxib及meloxicam均能有效抑制体外培养的HT-29、SW480结肠癌细胞生长,并具有良好的量-效关系。Western blot表明,HT-29细胞表达COX-2,而SW480细胞不表达COX-2。三种结肠癌细胞均表达NAG-1基因mRNA,其中LS174-T细胞NAG-1基础水平较低;NSAID能不同程度上调结肠癌细胞NAG-1基因表达。NSAID能有效抑制结肠癌细胞生长,这种作用可能部分通过诱导结肠癌细胞NAG-1基因表达实现,NAG-1基因表达不受肿瘤细胞是否表达COX-2的影响。     

Mutagenicity of Ayahuasca and Their Constituents to the Salmonella/Microsome Assay

Ayahuasca is a beverage used in religious rituals of indigenous and nonindigenous groups, and its therapeutic potential has been investigated. Ayahuasca is obtained by decoction of the Banisteriopsis caapi that contains β-carbolines (harmine, harmaline, and tetrahydroharmine) plus Psychotria viridis that contains N,N-dimethyltryptamine. Although plants used in folk medicine are recognized as safe, many of them have genotoxic potential. The Salmonella/microsome assay is usually the first line of the mutagenicity evaluation of products intended for therapeutic use. Our objective was to evaluate the mutagenicity of ayahuasca beverage and their constituents using the Salmonella/microsome assay with TA98 and TA100. We analyzed two ayahuasca samples, and also beverage samples prepared each individual plant P. viridis and B. caapi. Harmine and harmaline were also tested. All beverage samples were chemically characterized and both ayahuasca samples could be considered representative of the beverages consumed in religious rituals. Both ayahuasca samples were mutagenic for TA98 and TA100 with and without S9, with similar potencies. The beverage obtained from P. viridis was not mutagenic, and beverage obtained from B. caapi was mutagenic for TA98 with and without S9. Harmine was nonmutagenic and harmaline was mutagenic only for TA98 without S9. Harmaline fully explain the mutagenicity observed with TA98 without S9 of both ayahuasca samples and the B. caapi beverage samples. We conclude that the ayahuasca samples are mutagenic and this effect is partially explained by harmaline, one of the β-carbolines present in the beverage. Other mutagenic compounds seem to be present and need to be further investigated. Environ. Mol. Mutagen. 60:269–276, 2019. © 2018 Wiley Periodicals, Inc.     

Cell cycle synchronizing properties of staurosporine

Staurosporine (SSP) is a microbial alkaloid isolated from cultures of Streptomyces. For its ability to specifically inhibit protein kinase C and other serine/threonine and tyrosine protein kinases, SSP has been utilized recently to synchronize cells in G1 and/or G2 phases of the cell cycle. In the present paper we focus on the synchronizing properties of SSP with respect to three human normal cell types (PHA-activated peripheral blood lymphocytes, HS-68 and WI-38) and eight human tumor cell cultures (SV-40 transformed WI-38, SW48, SW480, A253, T-24, A549, MOLT-4 and HL-60). We describe procedures for maintenance and synchronization of these cells in culture. We provide the DNA/RNA flow cytometric methodology to verify cell synchronization and to evaluate the position of cell accumulation in specific phase and the level of synchrony. Synchronization in G1 is being achieved in the three normal cell lines after 24h SSP treatment with low concentrations (5–10 ng/ml) and in G2 after 24h treatment at higher SSP concentrations (50–100 ng/ml) in four of the eight tumor cell lines (A253, SW48, SW480 and A549). The other four tumor cell cultures (SV-40, WI-38, T-24, MOLT-4 and HL-60) show, at 50–100 ng/ml SSP concentration, an apparent G2 block, which is actually due to the presence of cells entering higher DNA ploidy levels. All other cell type/SSP dose combinations fail to induce cell synchronization. We also report a summary of the literature data about cell synchronization with SSP in other cell lines. Our results, together with the results from the literature, suggest that, while SSP may be useful for synchronizing normal cells in G1, its application for synchronizing tumor and/or transformed cells is limited. Critical comments follow, as well as suggestions and words of caution addressed to the future users of SSP as a cell synchronizing agent.Abbreviations AO acridine orange - SSP staurosporine     

La/SSB ribonucleoprotein levels increased in transformed cells.

Autoantibodies to the La/SSB ribonucleoprotein are commonly found in patients with Sjögren''s syndrome. Previous studies have shown that La/SSB accumulates in cells shortly after viral infection. We have extended these studies by investigating levels of the La/SSB antigen in virally and spontaneously transformed cell lines (contact-insensitive and tumourigenic) relative to their non-transformed counterpart cell lines (contact-sensitive and non-tumourigenic). Transformed BALB/3T12-3 and KNRK fibroblasts were visibly brighter by immunofluorescence assay than non-transformed BALB/3T3 and NRK fibroblasts respectively, when reacted with anti-La/SSB specific sera. This was confirmed by flow cytometry, as La/SSB levels were elevated in the transformed counterparts of the same cell lines. An anti-Sm monoclonal antibody and normal human serum reacted with these cell lines failed to show a significant increase by flow cytometry. Finally, a two-fold increase in the La/SSB antigen was demonstrated in cell lysates of these cell lines by a capture ELISA. These data show that La/SSB is elevated in transformed cell lines compared with non-transformed counterpart cell lines and suggest that this increase is not restricted to viral transformation.     

miR-126 对结肠癌细胞生物学行为的影响及其在调控结肠癌EMT 转化中的作用

目的:观察miR-126 在不同转移潜能的人结肠癌细胞系中的表达情况及其对结肠癌细胞增殖、侵袭转移能力的影响并探讨可能的作用机制。方法:采用实时荧光定量PCR 检测结肠癌细胞系(SW480、SW620 及HCT116)中miR-126 的表达量。通过脂质体瞬时转染法将miR-126 过表达(miR-126 mimics),并设置阴性对照组,然后采用CCK8 法检测细胞的增殖能力,细胞划痕实验检测细胞的迁移能力,Transwell 侵袭小室实验检测细胞的侵袭能力,Western blot 实验检测E-cadherin 和Vimentin 蛋白表达量的变化。结果:相对于低转移潜能的结肠癌细胞株SW480,miR-126 在高转移潜能的SW620 和HCT116细胞中的表达降低。过表达miR-126 可使SW620 细胞增殖、迁移和侵袭能力降低,E-cadherin 蛋白表达增加,Vimentin 蛋白表达降低,差异具有统计学意义(P<0.05)。结论:低表达的miR-126 与结肠癌的转移密切相关,miR-126 影响结肠癌细胞生物学行为的作用可能是通过调控EMT 进程实现的。     

马钱子碱通过抑制IL-6/STAT3信号通路诱导结肠癌SW480细胞凋亡

目的:探讨马钱子碱(brucine)在体外对人结肠癌SW480细胞生长和凋亡的影响及可能的分子机制。方法:实验以人结肠癌细胞系SW480细胞为研究对象,分为空白对照组、brucine(1μmol/L)处理组、IL-6(100μg/L)处理组和brucine(1μmol/L)与IL-6(100μg/L)联用组,用CCK-8法检测细胞活力抑制率;流式细胞术Annexin V/PI双染法检测细胞凋亡;Western blot法检测凋亡相关蛋白表达。细胞免疫荧光检测相关蛋白表达定位和强度。结果:Brucine处理组和brucine与IL-6联用组都能抑制结肠癌细胞的活力,brucine浓度相同时,联用组抑制率小于brucine处理组(P0.05)。与空白对照组相比,单用brucine处理组凋亡细胞明显增多(P0.05)。与单用brucine相比,brucine与IL-6联用组凋亡细胞明显减少(P0.05)。与对照组相比,brucine能降低p-STAT3蛋白水平。与空白对照组相比,单用brucine组p-STAT3的蛋白减少,抗凋亡蛋白Bcl-2表达减少,促凋亡蛋白Bax和执行凋亡的cleaved PARP明显增多;与空白对照组相比,单用IL-6处理组的p-STAT3明显增多(P0.05);而与单用brucine相比,brucine与IL-6联合应用组的p-STAT3蛋白增多,抗凋亡蛋白Bcl-2表达增多,促凋亡蛋白Bax和执行凋亡的cleaved PARP均相对减少(P0.05)。结论:体外细胞实验中brucine可能通过调节IL-6/STAT3通路,抑制结肠癌SW480细胞中STAT3的磷酸化激活,从而发挥抗肿瘤作用。     

阿司匹林对胰腺癌细胞周期的影响及其机制

目的： 观察阿司匹林及其催化产物前列腺素E2（PGE2）对胰腺肿瘤细胞周期及细胞周期相关蛋白p21Wafl/cipl、p27Kipl/pic2表达的影响，探讨阿司匹林抗胰腺癌的作用机制。 方法： 以阿司匹林和PGE2处理胰腺癌细胞后，分别采用MTT检测细胞活力、ELISA检测细胞内PGE2浓度、流式细胞仪检测细胞周期变化、Western blotting检测细胞周期相关蛋白p21Wafl/cipl和p27Kipl/pic2的表达水平。 结果： 阿司匹林可抑制胰腺癌细胞生长并呈剂量依赖性减少细胞内PGE2的生成；阿司匹林可诱导细胞周期相关蛋白p21Wafl/cipl和p27Kipl/pic2表达升高并引起细胞阻滞在G0/G1期。但外源性PGE2并不能拮抗阿司匹林对细胞活力、细胞周期及细胞周期相关蛋白的影响。 结论： 阿司匹林抑制胰腺癌细胞的生长可能并非完全通过环氧合酶途径；诱导p21Wafl/cipl和p27Kipl/pic2表达的升高、进而诱导细胞周期的阻滞可能是其作用机制之一。     

CTNNB1基因沉默抑制结肠癌SW480细胞生长的研究

目的探讨人结肠癌SW480细胞的CTNNB1基因沉默效应和对细胞生长的抑制作用。方法构建靶向CTNNB1的shRNA载体质粒,然后转染入结肠癌SW480细胞。用RT-PCR和Western Blot方法检测CTNNB1的mRNA和蛋白的表达情况。MTT实验评价转染后各组细胞的增殖情况。结果靶向CTNNB1的shRNA能够明显下调CTNNB1mRNA和蛋白质表达(P0.05),其抑制率分别是38.29%和42.86%。MTT实验提示转染了特异性CTNNB1shRNA的CTN实验组细胞在转染后呈现随着时间延长而进行性生长抑制的现象。在转染后72h,CTN组的细胞存活率为43.7%,与空白对照组相比有显著性降低。结论靶向CTNNB1的特异性shRNA对结肠癌SW480细胞具有下调CTNNB1基因表达,并显著抑制细胞增殖的效应。     

蚯蚓体腔液体外抗肿瘤作用的实验研究

目的 探讨蚯蚓体腔液（Earthworm coelomic fluid,ECF）对肿瘤细胞株Siha,SW480,Colo205和PC12的生长抑制作用及作用机制.方法 通过MTT法、流式细胞仪检测及形态学观察分析蚯蚓体腔液粗提物对肿瘤细胞株及正常细胞株（Cos7）的增殖抑制作用.结果 ECF对Siha、SW480、Colo205、PC12细胞的生长均有抑制作用,但对不同肿瘤细胞系的敏感度不同.结论 蚯蚓体腔液粗提物在体外通过诱导肿瘤细胞凋亡有明显的抗肿瘤作用.     

KLF4对结直肠癌细胞生长抑制及化疗敏感性的影响

目的:探讨Krüppel样因子4(KLF4)对结直肠癌细胞活力、凋亡及顺铂化疗敏感性的影响。方法:Western blot法检测KLF4在结直肠癌Caco2、SW480和HCT116细胞中的表达。将SW480细胞分为pc DNA3. 1组(转染pc DNA3. 1空质粒)、pc DNA3. 1-KLF4组(转染构建的pc DNA3. 1-KLF4过表达质粒)和pc DNA3. 1-KLF4+顺铂组(转染pc DNA3. 1-KLF4 48 h后用1 mg/L顺铂处理细胞48 h),Western blot检测KLF4、p-IκBα、细胞周期素D1(cyclin D1)和生存素(survivin)的蛋白水平; CCK-8法检测各组细胞活力;流式细胞术检测细胞凋亡率; DCFH-DA探针检测活性氧簇(ROS)含量。结果:KLF4在结直肠癌细胞中的表达均显著低于在人结肠黏膜上皮NCM460细胞的表达(P 0. 05)。与pc DNA3. 1组相比,pc DNA3. 1-KLF4组的KLF4蛋白表达显著增高(P 0. 05),细胞活力及cyclin D1和survivin的蛋白表达均显著降低,细胞凋亡率、ROS含量及p-IκBα的蛋白表达均显著增高;而pc DNA3. 1-KLF4+顺铂组细胞活力及cyclin D1和survivin的蛋白表达均显著低于pc DNA3. 1-KLF4组,细胞凋亡率、ROS含量及p-IκBα的蛋白表达均显著高于pc DNA3. 1-KLF4组(P 0. 05)。结论:上调结直肠癌细胞KLF4基因表达可降低肿瘤细胞活力,诱导细胞凋亡,增强顺铂化疗敏感性,其机制可能与提高细胞内ROS含量及下调NF-κB信号关键分子IκBα的磷酸化水平有关。     

miR-496过表达抑制结肠癌细胞生长和转移

目的:研究miR-496过表达对结肠癌细胞生长和转移的影响及其分子机制。方法:运用生物信息学软件筛选miR-496靶向相互作用蛋白;real-time PCR和Western blot法测定结肠癌细胞系HT29、HCT116、SW480以及正常结肠上皮细胞NCM460中miR-496、CTNNB1 mRNA和β-catenin蛋白的表达;运用Lipofectamine 2000将miR-496 mimics转染HT29、HCT116和SW480细胞,分别命名为HT29-miR-496 mimics、HCT116-miR-496 mimics和SW480-miR-496 mimics细胞,转染scramble为阴性对照;运用MTT法、乳酸脱氢酶(LDH)试剂盒法、克隆形成实验和Transwell分别测定细胞活力、LDH漏出率、克隆形成能力和转移能力;萤光素酶报告基因实验测定miR-496启动子活性;Western blot法测定β-catenin、真核细胞翻译起始因子4E结合蛋白1(4E-BP1)、p-4E-BP1、低密度脂蛋白受体相关蛋白6(LRP6)、p-LRP6、MMP-7、MMP-9、MMP-13以及TIMP-2的蛋白水平。结果:miR-496与β-catenin内源性相互作用;miR-496在HT29、HCT116和SW480细胞中低表达,而在NCM460高表达;β-catenin在HT29、HCT116和SW480细胞中高表达,而在NCM460低表达;培养24 h、48 h、72 h、96 h的HT29-miR-496 mimics、HCT116-miR-496 mimics和SW480-miR-496 mimics细胞活力、LDH漏出率、克隆形成率和转移的细胞数均显著低于对照组(P0.05);萤光素酶报告基因实验结果显示转染miR-496 mimics细胞中的miR-496启动子活性明显增加(P0.05),分别是对照组的1.75倍、2.04倍和1.61倍。Western blot实验结果显示miR-496过表达抑制β-catenin蛋白表达,p-4E-BP1和p-LRP6的蛋白水平降低;siRNA或miR-496过表达介导的β-catenin表达下调能显著抑制MMP-7和MMP-9的表达,促进TIMP-2的表达。结论:miR-496在结肠癌细胞中低表达,在正常结肠上皮细胞中高表达;miR-496过表达抑制结肠癌细胞的生长和转移,其机制是通过抑制Wnt/β-catenin通路进一步抑制MMP-7和MMP-9表达,促进TIMP-2表达,从而抑制结肠癌细胞的恶性表型。     

重组人肿瘤坏死因子与阿霉素抗人结肠癌细胞株（SW480）的序贯作用研究

目的 评价rHuTNF和阿霉素抗人结肠癌细胞株的序贯作用。方法 采用克隆生成试验（Hamburger-Salmon法）,研究rHuTNF和DOX序贯作用于SW480细胞后的抗增殖效果。结果 对结肠癌细胞系SW480,存在DOX至rHuTNF序贯抗增殖作用;除反序贯给药情况外,出现显著的协同作用。结论 在DOX存在情况下,TNF的抗瘤作用增强,从而支持DOX可干扰细胞保护机制以使瘤细胞对TNF细胞毒作用更为敏感的理论。     

具有相同遗传背景的人结肠癌细胞系生物学特性的鉴定

目的 对三种取自不同转移部位的结肠癌细胞系进行生物学特性的鉴定.方法 从体内成瘤性、原位移植后的自发性转移能力,以及体外生长、克隆形成率、粘附、运动、侵袭能力等方面,探讨具有相同遗传背景的SW480、SW620以及SW480/M5三种细胞系生物学特性的差异.结果 体内实验证明SW480具有多器官转移的潜能,SW620只具有淋巴结转移的能力,SW480/M5只具有肝脏转移的能力,SW480/M5的皮下瘤生长速度最快,其次是SW620细胞;体外实验证明W48/M5和SW620的体外生长、克隆形成能力均强于SW480细胞,而两者对纤维黏连蛋白的粘附能力较SW480细胞弱,SW480/M5的运动及侵袭能力强于SW480及SW620细胞.结论 与SW480细胞相比,SW480/M5和SW620细胞具有一定的器官亲和力,三者的遗传背景一致,是研究结肠癌晚期演进的遗传改变的重要资源.     

整合素αvβ6对结肠癌细胞中整合素αvβ5内吞胞吐循环的影响

 目的：探讨整合素αvβ6对结肠癌细胞中整合素αvβ5内吞胞吐循环及细胞黏附、迁移能力的影响。方法：采用Western blotting检测不同细胞中整合素αvβ6和αvβ5的表达情况,通过整合素内吞实验、胞吐实验和capture-ELISA实验检测不同细胞中整合素αvβ6和αvβ5的内吞胞吐循环时相,利用细胞黏附实验和细胞迁移实验检测各种细胞在不同基质表面黏附和迁移能力的差异。结果：SW480、SW480 wild-type β6和SW480 mock细胞中整合素αv亚基和β5亚基的表达无显著差异（P>0.05）,SW480 wild-type β6细胞中整合素β6亚基的表达显著高于另外2种细胞（P<0.05）;SW480细胞中整合素αvβ5存在内吞胞吐循环,但当向SW480细胞中转染β6亚基后,整合素αvβ6进行内吞胞吐循环的同时,会对整合素αvβ5的内吞和胞吐过程产生抑制作用,差异有统计学意义（P<0.05）;3种细胞中整合素αvβ6和αvβ5的内吞胞吐循环的差异,会影响细胞在纤连蛋白（整合素αvβ6配体）和玻连蛋白（整合素αvβ5配体）表面的黏附和迁移能力。结论：整合素αvβ6和αvβ5拥有共同的α亚基,它们在细胞内的内吞胞吐循环存在某种竞争性关系,当二者同时存在时,整合素αvβ6会抑制αvβ5的内吞胞吐循环过程,并由此对细胞在相应基质表面黏附和迁移能力产生影响。