Epigenetic modification regulates both expression of tumor-associated genes and cell cycle progressing in human colon cancer cell lines: Colo-320 and SW1116

The aim of this study is to assess the effects of DNA methylation and historic acetylation, alone or in combination, on the expression of several tumor-associated genes and cell cycle progression in two established human colon cancer cell lines: Colo-320 and SW1116. Treatments with 5-aza-2'-deoxycytidine (5-aza-dC) and trichostatin A, alone or in combination, were applied respectively. The methylation status of the CDKN2A promoter was determined by methyla-tion-specific PCR, and the acetylated status of the histones associated with the p21WAF1 and CDKN2A genes was examined by chromatin immunoprecipitation. The expression of the CDKN2A, p21WAF1, p53, p73, APC, c-myc, c-Ki-ras and survivin genes was detected by real-time RT-PCR and RT-PCR. The cell cycle profile was established by flow cytometry. We found that along with the demethylation of the CDKN2A gene promoter in both cell lines induced by 5-aza-dC alone or in combination with TSA, the expression of both CDKN2A and APC genes increased. The treatment of TSA or sodium butyrate up-regulated the transcription of p21WAF1 significantly by inducing the acetylation of histones H4 and H3, but failed to alter the acetylation level of CDKN2A-associated histones. No changes in transcription of p53, p73, c-myc, c-Ki-ras and survivin genes were observed. In addition, TSA or sodium butyrate was shown to arrest cells at the G1 phase. However, 5-aza-dC was not able to affect the cell cycle progression. In conclusion, regulation by epigenetic modification of the transcription of tumor-associated genes and the cell cycle progression in both human colon cancer cell lines Colo-320 and SW1116 is gene-specific.

Radiosensitivity of human colon cancer cell enhanced by immunoliposomal docetaxel

AIM:To enhance the radiosensitivity of human colon cancer cells by docetaxel. METHODS: Immunoliposomal docetaxel was prepared by coupling monoclonal antibody against carcinoembryonic antigen to cyanuric chloride at the PEG terminus of liposome. LoVo adenocarcinoma cell line was treated with immunoliposomal docetaxel or/and irradiation. MTT colorimetric assay was used to estimate cytotoxicity of immunoliposomal docetaxel and radiotoxicity. Cell cycle redistribution and apoptosis were determined with flow cytometry. Survivin expression in LoVo cells was verified by immunohistochemistry. D801 morphologic analysis system was used to semi-quantify immunohistochemical staining of survivin. RESULTS: Cytotoxicity was induced by immunoliposomal docetaxel alone in a dose-dependent manner. Immunoliposomal docetaxel yielded a cytotoxicity effect at a low dose of 2 nmol/L. With a single dose irradiation, the relative surviving fraction of LoVo cells showed a dose-dependent response, but there were no significant changes as radiation delivered from 4 to 8 Gy. Compared with liposomal docetaxel or single dose irradiation, strongly radiopotentiating effects of immunoliposomal docetaxel on LoVo cells were observed. A low dose of immunoliposomal docetaxel could yield sufficient radiosensitivity. Immunoliposomal docetaxel were achieved both specificity of the conjugated antibody and drug radiosensitization. Combined with radiation, immunoliposomal docetaxel significantly increased the percentage of G2/M cells and induced apoptosis, but significantly decreased the percentage of cells in G2/G1 and S phase by comparison with liposomal docetaxel. Immunohistochemical analysis showed that the brown stained survivin was mainly in cytoplasm of LoVo cells. Semi-quantitative analysis of the survivin immunostaining showed that the expression of survivin in LoVo cells under irradiation with immunoliposomal docetaxel was significantly decreased. CONCLUSION: Immunoliposomal docetaxel is strongly effective for target radiosensitation in LoVo colon carcinoma cells, and may offer the potential to improve local radiotherapy.

Anti-cancer effect of ethylacetate fraction from Orostachys japonicus on HT-29 human colon cancer cells by induction of apoptosis through caspase-dependent signaling pathway

Objective: To investigate the anti-colon cancer effects of ethylacetate fraction from Orostachys japonicus(0. japonicus) on HT-29 cancer cells. Methods: The viability of HT-29 cells was assayed by the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2 H-tetrazolium(MTS) method. Apoptosis induction and cell cycle inhibition were confirmed by fluorescein isothiocyanate and propidium iodide staining using flow cytometry.Morphological changes in the nucleus were observed, using a fluorescence microscope with4',6-diamidino-2-phenylindole(DAPI) nuclear staining. The expression levels of the upstream and downstream proteins involved in the anti-cancer mechanism were confirmed by Western blotting. Results: After treating HT-29 cells with different concentrations of ethylacetate fraction from O. japonicus, the viability of cells decreased in a concentration-dependent manner,while apoptosis induction and apoptotic body formation increased. Cell cycle analysis showed that the arrest occurred at the sub-G_1 and S phase. Among the upstream and downstream proteins involved in anti-cancer activity, the level of B cell lymphoma-2 decreased, and the bcl-2-associated x protein increased. The level of pro-caspase-3, pro-caspase-8, and pro-caspase-9 decreased, while the level of cleaved-caspase-3, cleaved-caspase-8, and cleaved-caspase-9 increased. Moreover, the phosphorylation, that is, activation of extracellular signal regulated kinase 1/2, Jun-N-terminal kinase, and p38 increased. Conclusions: Combining the above results, it is thought that the survival of HT-29 cells is suppressed by ethylacetate fraction from0. japonicus through mitochondrial regulation-induced caspase cascade activation, induction of apoptosis and cell cycle arrest.

Expression of T-STAR gene is associated with regulation of telomerase activity in human colon cancer cell line HCT-116

AIM： To investigate the effects on telomerase activity of transfection of human T-STAR gene full-length sense cDNA or partial antisense cDNA into human colon cancer cell line HCT-116.METHODS： mRNA and protein expression levels of T-STAR gene were determined by RT-PCR and western blot, and telomerase activity was measured by PCR- ELISA, after transfection of T-STAR sense or antisense gene into HCT-116 cells with lipofectamine. RESULTS： T-STAR gene expression was enhanced or knocked down both at mRNA and protein levels, and telomerase activity was significantly increased or decreased. CONCLUSION： The T-STAR gene may participate in regulation of telomerase activity in human colon cancer HCT-116 cells in a parallel fashion.

Pro-apoptotic Effects of OSNQ on Human Colon Cancer SW480 Cells

[Objectives] The aim was to elucidate the pro-apoptosis mechanism of naphthoquinone derivative 2-octyl sulfoxide-1,4-naphthoquinone(OSNQ) on human colon cancer SW480 cells.[Methods]The cytotoxic effect of OSNQ on colon cancer SW480 cells was detected by MTT colorimetry.The pro-apoptotic effect of OSNQ on human colon cancer SW480 cells was detected by Annexin V-FITC/PI double staining.The changes in expression of apoptosis-related proteins were detected by Western blot.[Results]The results of MTT assay showed that OSNQ had a significant cytotoxic effect on colon cancer SW480 cells.The results of Western blot showed that OSNQ induced the apoptosis in colon cancer SW480 cells through promoting the expression of pro-apoptotic caspase-3 and inhibiting the expression of apoptosis-inhibiting protein Bcl-2.[Conclusions] OSNQ has a significant cytotoxic effect on colon cancer SW480 cells,and it induces the apoptosis of colon cancer SW480 cells by AKT signaling pathway.

Estradiol agonists inhibit human Lo Vo colorectal-cancer cell proliferation and migration through p53

AIM: To investigate the effects of 17β-estradiol via estrogen receptors (ER) or direct administration of ER agonists on human colorectal cancer.

Fermented Herbal Decoction Selectively Targeting Human Cancer Cell Line and Human Pathogenic Microorganism

Introduction: Prolonged immuno-suppressed status promised to induce internal growth of malignant cell and infectious agent, yet, only a small part of affected individuals seek medical attention or berried by commercially over-flowed fake information. Several studies have described complementary and alternative medicine as effective strategies for improving anti-infectious agent including malignant cell. The purpose of this study was to investigate the effect of a fermented herbal decoction (FHD) both in vitro and in vivo to malignant cells and microorganism by regulating leukocyte subset proportioning FHD as dietary material. Methods: In this approach of alternative study, selective anti-cancer effect by fermented decoction was tried to show first in vitro system both, cancer cell and virus strain. The fermented herbal decoction consisting of 80 sorts of herbs and fruits. The selective toxicity was set up and then for immunological factors in animal and human. The most important factor is to reduce side effect for a normal cell. Results: First, FHD was proved as safe by animal test. FHD regulated also the proportion of granulocyte and lymphocyte ratio both animal and human. In vitro culture showed selective toxicity by FHD against human melanoma and leukemia cell line but reduced toxicity was showed by normal cell line. As for the anti-virus activity, anti-virus effect was tested on the feeder layer of human fibroblast cell, after 9 days of culture. Second, FHD inhibits colon cancer growth in 3-methylholanthrene induced cancer in rat. Conclusion: The present results suggest that our fermented herbal decoction showed selective anti-cancer activities and anti-virus activities, together with the regulative effect on the immune system.

探讨DetectCell~染色在良恶性细胞鉴别中的价值

目的:用DetectCell染色人结肠癌细胞(HT-29)和小鼠胚胎成纤维细胞(C3H)细胞,探索DetectCell染色在细胞良恶性鉴别中的价值。方法:DetectCell染色试剂主要由含有酸性红,碱性绿和具有特殊反应亲和力的无花果属植物提取液组成。通过检测各主要染色试剂pH值、稀释浓度波长的吸光度比值(OD540/OD630)以控制染色试剂的检测标准,然后进行DetectCell染色观察细胞形态与颜色特征。结果:DetectCell主要染液的pH值和540 nm/630 nm波长处OD值均符合检测标准;DetectCell染色HT-29细胞和C3H细胞能保持原有细胞的形态,同时分别使纤维母细胞C3H被染成绿色,使癌细胞HT-29被染成红色。结论:DetectCell染色使癌细胞呈红色,非癌细胞呈绿色,并不影响细胞形态特征,因此该染色提供了颜色和形态双重分析功能。

Identification of an anticancer compound against HT-29 cells from Phellinus linteus grown on germinated brown rice

Objective:To isolate and identify the anticancer compound against proliferation of human colon cancer cells from ethyl acetate(EtOAc)extract ol Phellinus linteus grown on germinated brown rice(PB).Methods:EtOAc extract of PB was partitioned with n-hexane,EtOAc,and water-saturated n-butanol.Anticancer compound of n-hexane layer was isolated and identified by HPLC and NMR,respectively.Cytotoxicity against HT-29 cells was tested by SRB assay.Results:The n-hexane layer obtained after solvent fractionation of PB EtOAc extracts showed a potent anticancer activity against the HT-29 cell line.Atractylenolide I,a eudesmane-type sesquiterpene lactone,a major anticancer substance of PB,was isolated from the n-hexane layer by silica gel column chromatography and preparative-HPLC.This structure was elucidated by one-and two-dimensional NMR spectroscopic data.Atractylenolide I has not been reported in mushrooms or rice as of yet.The isolated compound dose-dependently inhibited the growth of HT-29 human colon cancer cells.Conclusions:Atractylenolide I might contribute to the anticancer effect of PB.

右美托咪定下调PI3K/AKT信号通路改善脂多糖诱导的结肠炎结肠上皮细胞损伤

为研究右美托咪定对脂多糖(LPS)诱导的人结肠上皮NCM-460细胞的炎症、增殖和凋亡的影响及磷脂酰肌醇-3-激酶/丝氨酸-苏氨酸激酶(PI3K/AKT)信号通路的调控作用,本研究体外培养人结肠上皮NCM-460细胞,将其分为对照组、LPS组(1μg/mL LPS)和不同质量浓度右美托咪定组(1μg/mL LPS+1.25、2.50、5.00和10.00μg/mL右美托咪定),干预24 h,筛选出合适的右美托咪定作用质量浓度用于后续试验。随后,将人结肠上皮NCM-460细胞分为对照组、LPS组、右美托咪定组(1μg/mL LPS+5.00μg/mL右美托咪定)、LY294002组(1μg/mL LPS+10μmol/L PI3K/AKT通路抑制剂LY294002)、抑制剂组(1μg/mL LPS+5.00μg/mL右美托咪定+10μmol/L LY294002)和激活剂组(1μg/mL LPS+5.00μg/mL右美托咪定+10μmol/L PI3K/AKT通路激动剂SC79),干预24 h。用细胞计数试剂盒-8(CCK-8)检测细胞活力;通过酶联免疫吸附试验(ELISA)检测肿瘤坏死因子-α(TNF-α)和白细胞介素-8(IL-8)的表达水平;用5-乙炔基-2'脱氧尿嘧啶核苷(EdU)测定细胞增殖率;用Hoechst 33258染色法测定细胞凋亡率;用蛋白免疫印迹(WB)法测定细胞周期蛋白D1(Cyclin D1)、剪切的半胱氨酸蛋白酶-3(cleaved Caspase 3)和PI3K/AKT信号通路关键蛋白的表达水平。根据细胞活力和炎症因子TNF-α的表达水平选择5.00μg/mL右美托咪定用于后续试验。结果显示,与对照组相比,LPS组细胞增殖率和Cyclin D1的表达水平显著降低(P<0.05),细胞凋亡率、TNF-α、IL-8、cleaved Caspase 3的表达水平、p-PI3K/PI3K及p-AKT/AKT的比值显著升高(P<0.05);右美托咪定组和LY294002组中的右美托咪定和LY294002扭转了LPS对人结肠上皮NCM-460细胞的上述作用(P<0.05);与右美托咪定组相比,抑制剂组中的LY294002增强了右美托咪定对LPS诱导的人结肠上皮NCM-460细胞的作用(P<0.05),激活剂组中的SC79则削弱了右美托咪定对LPS诱导的人结肠上皮NCM-460细胞的作用(P<0.05)。研究表明,右美托咪定能促进LPS诱导的人结肠上皮NCM-460细胞增殖,抑制其炎症和凋亡,其作用机制可能与阻滞PI3K/PI3K信号通路信号转导有关。本研究为结肠炎的治疗提供了新的方向。

盐酸小檗碱对人结肠癌细胞SW480增殖、迁移及侵袭的影响

目的探究盐酸小檗碱对人结肠癌细胞SW480增殖、迁移和侵袭过程的影响及可能的机制。方法将人结肠癌细胞SW480细胞分成实验组、对照组、空白组,用CCK8法测定不同浓度的盐酸小檗碱对SW480细胞增殖的作用,并计算出盐酸小檗碱不同浓度作用下SW480细胞的存活率;通过平板克隆形成、细胞划痕、Transwell等实验,明确盐酸小檗碱对SW480的克隆形成、迁移及侵袭的作用。结果盐酸小檗碱能明显地抑制SW480细胞的增殖,并表现出明显的时间和浓度依赖关系;盐酸小檗碱对SW480细胞的克隆形成、迁移及侵袭过程有显著的抑制作用,差异有统计学意义(P<0.05)。结论盐酸小檗碱对细胞SW480的克隆形成、增殖、侵袭和迁移过程均有明显的抑制作用。

罗哌卡因减轻LPS诱导的人结肠上皮细胞系NCM-460凋亡

目的探究罗哌卡因对脂多糖(LPS)诱导的人结肠上皮细胞系NCM-460凋亡和对核苷酸寡聚化结构域(NOD)样受体蛋白3(NLRP3)炎性小体活性的影响。方法体外培养人结肠上皮细胞系NCM-460,将细胞分组:对照组(control,不干预)、模型组(model,10μg/mL的LPS处理)、低/中/高浓度组(0.5、1、1.5 mmol/L罗哌卡因干预模型组)。然后将细胞分为对照组、模型组、罗哌卡因组(1.5 mmol/L罗哌卡因干预模型组)、罗哌卡因+抑制剂组(1μmol/L NF-κB通路抑制剂BAY 11-7082干预罗哌卡因组)、抑制剂组(1μmol/L NF-κB通路抑制剂BAY 11-7082干预罗哌卡因组)和罗哌卡因+激活剂组(1μmol/L NF-κB通路激活剂Prostratin干预罗哌卡因组),干预24 h。采用酶联免疫吸附试验(ELISA)检测IL-6、IL-8及肿瘤坏死因子-α(TNF-α)水平;EdU掺入法检测增殖率、Hoechst 33258染色法检测凋亡率;Western blot检测周期蛋白D1(cyclinD1)、半胱氨酸天冬氨酸蛋白酶-3(caspase-3)、NLRP3和NF-κB通路相关蛋白水平。结果与对照组相比,模型组细胞活力降低,高浓度罗哌卡因组活力升高(P<0.05)。与对照组相比,模型组细胞炎性因子IL-6、IL-8、TNF-α浓度、凋亡率和caspase-3、NLRP3、磷酸化(p)-NF-κB蛋白水平上升(P<0.05),增殖率和cycilnD1蛋白水平下降(P<0.05);与模型组相比,罗哌卡因组和抑制剂组IL-6、IL-8、TNF-α浓度、凋亡率和caspase-3、NLRP3、p-NF-κB蛋白水平下降(P<0.05),增殖能力和cycilnD1蛋白水平上升(P<0.05);与罗哌卡因组相比,罗哌卡因+抑制剂组上述指标趋势变化更加显著(P<0.05),罗哌卡因+激动剂组则显著扭转了这些指标趋势(P<0.05)。结论罗哌卡因抑制LPS诱导的NCM-460细胞凋亡,促进增殖,NF-κB通路可能参与起作用。

复方葛根汤诱导结肠癌HCT116细胞铁死亡分子机制研究

为探究复方葛根汤对结肠癌HCT116细胞增长作用及其分子机制,通过MTT法检测、克隆形成、形态学分析探讨复方葛根汤对HCT116细胞增长作用,以活性氧试剂盒检测、荧光显微成像及蛋白免疫印迹法探究其分子机制。研究结果显示,与溶媒对照组相比,复方葛根汤能显著抑制HCT116细胞增长能力,并呈浓度和时间依赖性,机制上能显著增加细胞内活性氧,显著上调铁死亡相关蛋白PTGS2、ACSL4蛋白的表达,及明显下调铁死亡相关蛋白GPX4表达,表明复方葛根汤可能通过诱导铁死亡机制抑制HCT116细胞增长。

DADS负调控uPAR/uPA信号抑制人结肠癌SW480细胞侵袭和EMT

目的探讨二烯丙基二硫(DADS)抑制人结肠癌SW480细胞侵袭和上皮间质转化(EMT)的可能机制。方法免疫组化检测结肠癌组织中尿激酶型纤溶酶原激活剂(uPA)受体(uPAR)的表达。基因转染技术构建uPAR过表达细胞。实验分为SW480组、SW480+DADS组、uPAR组、uPAR+DADS组。迁移、侵袭实检测各组细胞迁移与侵袭能力。RT-PCR、Western blotting分别检测相关信号通路分子mRAN及其蛋白的表达。裸鼠实验验证DADS对uPAR过表达SW480细胞移植瘤的影响。结果结肠癌组织中uPAR表达显著高于癌旁正常黏膜组织(P<0.05)。成功构建稳定uPAR过表达SW480细胞。uPAR过表达上调uPA、uPAR表达,而DADS下调uPA、uPAR表达。uPAR过表达增强细胞迁移、侵袭能力,DADS抑制uPAR过表达细胞的迁移、侵袭能力。DADS通过下调Vimentin、基质金属蛋白酶(MMP-9)表达,上调E-cadherin、组织金属蛋白酶抑制物(TIMP)-3表达抑制SW480细胞EMT。裸鼠实验结果显示,DADS可体内抑制uPAR过表达SW480细胞EMT。结论DADS通过负调控uPAR/uPA信号体内外抑制人结肠癌SW480细胞侵袭和EMT。

SOX4靶向miR-17对结肠癌细胞HCT-116生物学行为的影响

目的探讨性别决定区Y框蛋白4(SOX4)及miR-17在结直肠癌中的表达及对HCT-116细胞生物学行为的作用。方法收集2020年3月至2022年1月在河北北方学院一附院和张家口市第一医院的27例结直肠癌患者组织标本并检测SOX4及miR-17的表达水平,并分析与临床病理特征的关系。利用慢病毒转染技术干预HCT-116细胞的SOX4及miR-17表达。检测各组细胞中SOX4和miR-17的表达及细胞增殖、侵袭、迁移能力、细胞活性变化和相关蛋白表达。结果与正常组织比较,结直肠癌组织中SOX4表达水平升高。SOX4及miR-17在结直肠癌组织中的表达呈正相关(r=0.724,P<0.001),SOX4和miR-17的表达和病理分期、淋巴结转移、肝转移情况相关,差异有统计学意义(P<0.05),而与肿瘤的大小、分化程度无相关(P>0.05)。SOX4模拟组细胞增殖能力、迁移能力及细胞活性显著高于对照组及SOX4抑制剂组(P<0.05)。SOX4抑制剂组与对照组相比迁移及增殖相关蛋白表达差异有统计学意义(P<0.05)。结论SOX4在结直肠癌组织中表达上调,SOX4的表达可促进结肠癌细胞增殖、迁移和侵袭能力,miR-17可能是其下游调控靶点。

姜黄素对人结直肠癌SW-620细胞抗肿瘤效果的研究

目的:研究姜黄素(Cur)对人结直肠癌SW-620细胞生长、迁移的抑制作用。方法:不同浓度Cur(2、5、10μg/mL)处理SW-620细胞后,采用MTT法检测细胞增殖能力变化,流式细胞仪分别结合Rh123、DCFH-DA、Annexin V-FITC/PI染色检测细胞线粒体膜电位(Δψ_(m))变化、活性氧簇(ROS)生成及细胞凋亡情况,彗星电泳观察细胞DNA损伤情况,荧光显微技术观察细胞凋亡特征,Transwell实验检测细胞迁移能力,扫描电子显微镜观察细胞表面结构变化。结果:与对照组相比,5、10μg/mL Cur处理24、48 h可显著抑制细胞增殖(t=5.28、21.8、18.19、33.19,均P<0.01),半数抑制浓度分别为6.46、3.75μg/mL。药物处理4 h,与对照组相比,2、5、10μg/mL Cur组细胞内ROS生成分别增加至15.8%、30.2%和45%(t=3.64、7.4、13.8,均P<0.05);Δψ_(m)下降的细胞比例分别为22.7%、38.5%和72.7%(t=7.7、11.32、45.26,均P<0.01);药物处理12、24 h,2、5、10μg/mL Cur组凋亡细胞比例分别为6.6%(t=3.79,P=0.11)、32.6%、68.7%(t=21.3、64.39,均P<0.01)和16.9%(t=10.37,P<0.05)、47.2%、78.9%(t=23.46、19.8,均P<0.01);药物处理12 h,2、5、10μg/mL Cur组迁移细胞的数量分别减少至79.66%(t=7.14,P<0.05)、53.36%和39.45%(t=21.91、25.04,均P<0.01)。结论:Cur可抑制人结直肠癌SW-620细胞增殖和迁移。

NF-κB对人结肠癌细胞上皮间质转化及侵袭转移的影响

目的:研究核转录因子-κB(nuclear factorkappa B,NF-κB)对人结肠癌细胞上皮间质转化(epithelial-mesenchymal transition,EMT)及侵袭和转移的影响.方法:将人结肠癌HCT116细胞分为NF-κB激活组,抑制组和空白对照组.分别用NF-κB活化激活剂肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α),终浓度为20 ng/mL,NF-κB活化抑制剂吡咯烷二硫代甲酸铵(ammonium pyrrolidinedithiocarbamate,PDTC),终浓度为20μmol/L干预HCT116细胞4 d.采用相差显微镜观察细胞形态变化,Transwell小室模型观察细胞侵袭迁移能力变化,Western blot检测p65、P-p65、E-cadherin和N-cadherin的蛋白表达,QT-PCR检测E-cadherin和N-cadherin的mRNA表达.结果:TNF-α可上调P-p65和N-cadherin的表达,抑制E-cadherin的表达,同时明显促进HCT116细胞的EMT形态发生(如细长丝状伪足和纺锤状细胞形成),并使侵袭和迁移能力增强;相反,PDTC则降低P-p65和N-cadherin的表达,而增加E-cadherin的表达,且抑制细胞的EMT形态发生(如伪足不明显,细胞成多角形并紧密排列)及减弱细胞的侵袭迁移能力.对照组、TNF-α组及PDTC组的侵袭细胞数(97.75±3.77 vs 118.50±1.95,51.00±1.83);迁移细胞数(140.00±4.32 vs 167.00±6.36,80.00±2.53);N-cadherin mRNA的表达(1.00±0.00 vs 3.90±0.47,0.08±0.02);E-cadherin mRNA的表达(1.00±0.00 vs0.26±0.08,6.03±0.59,均P<0.05).结论:NF-κB可以促进结肠癌HCT116细胞的EMT发生、侵袭和转移.

螺旋藻藻蓝蛋白对癌激光疗法增敏作用的实验研究

用藻蓝蛋白处理2种癌细胞作体内外激光治癌试验。人大肠癌细胞株HR_(8348)培养后分别用100μg,50μg和25μg的藻蓝蛋白处理,经光波为630nm的铜激光辐照12J/cm^2,用MTT法检测培养癌细胞存活率分别为22.2％,37.6％和89.7％,显示良好的剂量效应。用S_(180)移植瘤小鼠,分别给予藻蓝蛋白注射2mg或口服20mg后,经铜激光辐照瘤体15d后,有效率分别为50％和53％,与对照组比较,具显著差异(P=0.007)。体内外试验证实藻蓝蛋白确具有光敏作用,且其无毒,无副作用,是一种理想的光敏剂。

三氧化二砷抗裸鼠人结肠癌移植瘤作用及其机制的研究

目的:探讨三氧化二砷(As2O3)抗人结肠腺癌裸鼠移植瘤作用、作用机制以及药物毒性。方法:建立人结肠癌裸鼠移植瘤模型,随机分为4组,即生理盐水组、5-氟脲嘧啶(5-FU)组、低剂量As2O3组和高剂量As2O3组,比较各组的抑瘤作用和裸鼠一般状态的变化,并对标本分别行光镜和电镜观察、原位末端标记(TUNEL)、免疫组化和血常规检测。结果:As2O3能够明显抑制结肠癌裸鼠移植瘤的增长,并能诱导癌细胞凋亡,调控相关基因表达;未见As2O3引起明显肝、肾和造血系统损害。结论:As2O3对人结肠腺癌细胞裸鼠移植瘤具有显著的抗癌作用,此作用可能与诱导癌细胞凋亡密切相关,且受到多种有关基因的调控;但是对裸鼠的肝、肾和造血系统无明显的毒性。

胎盘间充质干细胞低氧培养液对肠黏膜上皮细胞氧化应激损伤的保护作用

目的研究胎盘间充质干细胞(p MSCs)低氧培养液对肠黏膜上皮细胞氧化应激损伤的作用。方法组织块培养法提取p MSCs,流式细胞术检测表面标志,ELISA检测p MSCs常氧(21%O_2)或低氧(1%O_2)培养5 d后培养液中胰岛素样生长因子1(IGF-1)的含量。人结肠腺癌细胞(Caco2)经100μmol/L H_2O_2处理12 h后分别培养于正常培养液、p MSCs常氧培养液或p MSCs低氧培养液,5 d后台盼蓝染色测细胞存活情况,MTT测细胞增殖,Annexin V-FITC/PI双染测细胞凋亡。结果 p MSCs阳性表达CD29,CD44。p MSCs低氧培养液中的IGF-1明显多于p MSCs常氧培养液(P<0.05)。与p MSCs常氧培养液相比,p MSCs低氧培养液中H_2O_2处理的Caco2存活细胞多,增殖快,凋亡少(P<0.05)。向p MSCs低氧培养液中加入IGF-1抗体后,细胞增殖减慢,凋亡增多(P<0.05)。结论 p MSCs低氧培养液对H_2O_2处理的Caco2具有保护作用。机制与IGF-1促进细胞增殖、抑制凋亡相关。