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.

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.

Antitumor Activities and Apoptosis-regulated Mechanisms of Fermented Wheat Germ Extract in the Transplantation Tumor Model of Human HT-29 Cells in Nude Mice

Objective A subcutaneous transplantation tumor model of human HT-29 cells in nude mice was established to evaluate anticarcinogenic activities, and the apoptosis-regulated mechanism effect of aqueous extract of fermented wheat germ with Lactobacillus plantarum dy-1 （LFWGE）. Methods The HT-29 cells were transplanted via subcutaneous injection of 1×10^7cells into the right flank of each nude mouse. Then, nude mice were treated for 30 d with LFWGE （high-dose 2 g/kg/d; low-dose 1 g/kg/d） and for 7 d with 5-fluorouracil （5-FU, 25 mg/kg/d） by gavage and intraperitoneal injection, respectively. An inhibition of tumor growth was observed. Results Tumor volume and weights decreased significantly in both groups of nude mice treated with LFWGE. In addition, the cell apoptosis rate of the LFWGE group （2 g/kg/d, 60.2%＋4.4%; 1 g/kg/d, 58.6%＋6.9%） was significantly higher than that of the control group （11.5%＋1.6%） and 5-FU group （32.1%＋3.5%） as measured by the TUNEL assay. Moreover, the real-time fluorescent quantitative PCR and Western blot method further confirmed these enhancing apoptosis and growth inhibition effects. The involvement of LFWGE in inducing apoptosis was confirmed by the expression of Bax, Bcl-2, Caspase-3, and CyclinD1. Conclusion The results showed that LFWGE could induce subcutaneous transplantation tumor apoptosis in nude mice and could be as a natural nutrient supplements or chemopreventive agent in the treatment of human colon cancer.

Antitumor Activities and Apoptosis-regulated Mechanisms of Fermented Barley Extract in the Transplantation Tumor Model of Human HT-29 Cells in Nude Mice

Objective A subcutaneous transplantation tumor model of human HT-29 cells was established in nude mice to study the anticarcinogenic activities and apoptosis-regulatory mechanistic effect of aqueous extract of fermented barley with Lactobacillus plantarum dy-1 （LFBE）. Methods HT-29 cells were transplanted via subcutaneous injection of 1 × 107cells into the right flank of each nude mouse. Then, nude mice were treated for 30 days with LFBE （high-dose 2 g·kg-1·d-1; low-dose 1 g·kg-1·d-1） and for 7 days with 5-fluorouracil （5-FU, 25 g·kg-1·d-1） by gavage and intraperitoneal injection, respectively. Results Tumor volume and weight decreased significantly in both groups of nude mice treated with LFBE. In addition, the cell apoptosis rate of the LFBE group was significantly higher than that of the control group and 5-FU groups as measured by the TUNEL assay. Moreover, the real-time fluorescent quantitative PCR and Western blot methods further confirmed these apoptosis-enhancing and growth-inhibiting effects. The involvement of LFBE in inducing apoptosis was confirmed by the expression of Bax, Bcl-2, caspase-3, and cyclin D1. Conclusion The results showed that LFBE could induce subcutaneous transplantation tumor apoptosis in nude mice and could be used as a natural nutrient supplement or chemopreventive agent in the treatment of human colon cancer.

Interaction between Colon Cancer Cells and Human Liver Sinusoidal Endothelial Cells Promotes Liver Metastasis of Tumor Cells

OBJECTIVE To investigate the effect of co-culture between colon cancer cells （SW1116） and human liver sinusoidal endothelial cells （HLSECs） on cancer cell metastasis, and to provide a novel model for studying the mechanism of colon cancer liver metastasis. METHODS HLSECs and SW1116 were co-cultured for 21 rounds in vitro. Transwell migration, gelatin-zymography, CCK-8 proliferation and colony formation assays were used to examine the invasion, proliferation, and colony forming ability of cancer cells. Assays were carried out to examine tumor growth ability and liver metastasis. The associated molecular change was examined by western blotting. RESULTS After 21 selection rounds, colon cancer cells SWl 1161）21 displayed a clear boundary. Compared with the 5W1116 cells, SW1116P21 cells had a greater invasive ability, cell proliferation and colony formation in soft agar. A gelatin-zymography assay showed that the ability of SW1116P21 cells to secrete matrix metalloproteinase-2/9 was significantly greater than that of SWl116 cells. Additionally, the capacity for subcutaneous tumor formation of SW1116P21 was significantly increased. It was found that mice injected with SW1116P21 cells developed significantly more visually observable liver nodules than mice injected with SW1116 cells. Western blotting showed increased vimentin expression and decreased E-cadherin expression in the SW1116P21 cells, compared with the SWl 116 cells. CONCLUSION The interaction between SW1116 and HLSECs may promote tumor cell invasion, proliferation and colony formation in vitro, and tumor formation and liver metastasis in vivo. An epithelial-mesenchymal transition occurs in SWl 116P21 cells, which contributes to the change in the characteristics of tumor cells.

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.

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.

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.

姜黄素类似物对人结肠癌HT-29细胞增殖与自噬的影响

目的初步探究姜黄素类似物——WH-8对人结肠癌HT-29细胞增殖和自噬的影响。方法选用不同浓度WH-8作用于人结肠癌HT-29细胞,应用四甲基偶氮唑盐还原法观察药物对细胞的生长抑制作用;通过荧光染色技术和细胞成像技术观察WH-8作用下细胞自噬囊泡的变化;四甲基偶氮唑盐还原法检测经自噬特异性抑制剂3-MA预处理后WH-8对细胞生长抑制率的影响;蛋白质印迹法观察WH-8作用下细胞自噬特征性蛋白酵母自噬相关基因1(Beclin 1)和微管相关蛋白1轻链3(LC3)的表达情况。结果WH-8呈时间-剂量依赖性抑制人结肠癌HT-29细胞增殖,48 h平均半数抑制浓度为(12.5±1.3)μmol/L;一定浓度下WH-8可诱导细胞的自噬囊泡增多;3-MA可逆转WH-8对人结肠癌HT-29细胞的生长抑制作用,差异有统计学意义(P<0.05);WH-8可诱导Beclin-1表达上调,且在一定时间内促进LC3Ⅰ向LC3Ⅱ转化。结论WH-8可抑制人结肠癌HT-29细胞增殖并诱导细胞自噬。

基于JAK2/STAT3信号通路探讨对叶百部总生物碱对人结肠癌HT-29细胞增殖、凋亡的影响

目的基于Janus激酶2(JAK2)/信号转导及转录激活因子3(STAT3)信号通路,探讨对叶百部总生物碱对人结肠癌HT-29细胞增殖、凋亡的影响。方法将人结肠癌HT-29细胞分为55μg/mL组、150μg/mL组和250μg/mL组进行实验,另设仅添加培养基的空白组(含细胞)。除空白组外,其他组给予相应浓度的对叶百部总生物碱进行干预。干预24 h、48 h、72 h后,采用四甲基偶氮唑蓝法检测各组细胞增殖抑制率;干预48 h后,采用Hoechst 33258染色法观察各组细胞凋亡情况,采用流式细胞术检测各组细胞凋亡率,采用Western blot检测各组细胞JAK2、磷酸化JAK2(p-JAK2)、STAT3和磷酸化STAT3(p-STAT3)的蛋白表达水平。结果与空白组比较,各浓度组细胞增殖抑制率增加;经Hoechst 33258染色后在各浓度组中可观察到典型的细胞凋亡形态改变,凋亡细胞数及细胞凋亡率均增加(均P<0.05);流式细胞术检测结果显示150μg/mL组和250μg/mL组细胞凋亡率增加(均P<0.05)。与空白组比较,各浓度组的p-JAK2蛋白和p-STAT3蛋白表达水平均下调(均P<0.05)。55μg/mL组、150μg/mL组和250μg/mL组的细胞增殖抑制率、凋亡细胞数及细胞凋亡率依次增加,p-JAK2蛋白和p-STAT3蛋白表达水平依次降低(均P<0.05)。结论对叶百部总生物碱可能通过抑制JAK2/STAT3信号通路相关蛋白的活化,来抑制人结肠癌HT-29细胞增殖并促进其凋亡。

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

AIM: To investigate the effects of 17&#x003b2;-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.

Pien Tze Huang(片仔癀)-Induced Apoptosis in Human Colon Cancer HT-29 Cells Is Associated with Regulation of the Bcl-2 Family and Activation of Caspase 3

Objective：To investigate the cellular effects of Pien Tze Huang（片仔癀,PZH） in the HT-29 human colon carcinoma cell line.Methods：The viability of HT-29 cells was determined by MTT assay.A fluorescence-activated cell sorting（FACS） analysis with annexin-V/propidium iodide（PI） and JC-1 staining were performed to determine cell apoptosis and the loss of mitochondrial membrane potential,respectively.Activation of caspase 3 was evaluated by a colorimetric assay.The mRNA expression levels of Bcl-2 and Bax were measured by reverse transcription polymerase chain reaction（RT-PCR）.Results：PZH,in a dose- and time-dependent manner,reduced viability and induced apoptosis of HT-29 cells.Moreover,PZH treatment resulted in the collapse of the mitochondrial membrane potential,activation of caspase 3,and an increase in the Bax/Bcl-2 ratio.Conclusion：PZH inhibits the growth of HT-29 cells by inducing cancer cell apoptosis via regulation of the Bcl-2 family and activation of caspase 3,which may,in part,explain its anticancer activity.

二烯丙基二硫对人结肠癌HT-29细胞G_1期的阻滞作用

目的探讨二烯丙基二硫(DADS)对人结肠癌HT-29细胞G1期的阻滞作用及分子机制。方法采用MTT、细胞计数法、流式细胞术和免疫细胞化学方法分析DADS对体外培养的HT-29细胞增殖抑制作用、细胞周期分布及细胞周期相关蛋白表达的影响。结果MTT法显示,60、120μmol.L-1DADS作用HT-29细胞24 h后,生长抑制率分别达23.1%、45.6%。细胞计数法表明,常规培养HT-29细胞群体倍增时间为22.58 h,60μmol.L-1DADS作用HT-29细胞后,其细胞群体倍增时间延长到31.20 h。流式细胞仪分析结果显示,60μmol.L-1DADS阻滞HT-29细胞在G1期,与对照组相比,可使G1期细胞增加约2倍,而120μmol.L-1DADS显著地将细胞阻滞在G2/M期。免疫细胞化学分析表明在G1期阻滞同时有p21W af1蛋白表达上调,Cyc lin E、C-myc蛋白表达下降。结论低剂量DADS对HT-29细胞的抑制增殖作用可能与G1期阻滞有关,DADS对HT-29细胞G1期阻滞的分子机制可能与调节p21W af1、Cyc lin E、C-myc表达相关。

苦参碱抑制大肠癌HT-29细胞环氧化酶-2表达的研究

目的从基因和蛋白水平探讨中药成分苦参碱 (matrine)对大肠癌HT-2 9细胞环氧化酶-2(COX-2 )表达的影响。方法分别采用RT-PCR、Western blot、ELISA等方法检测不同浓度苦参碱处理HT-2 9细胞前后COX-2mRNA、蛋白及其产物前列腺素E2 (PGE2 )水平的改变。结果苦参碱可抑制HT-2 9细胞COX-2mRNA、蛋白表达及PGE2 合成水平 ,但对COX 1无影响。当苦参碱 2 .0mg/ml处理时 ,COX 2mRNA表达在处理后 6h和 9h时抑制率均为 10 0 % ;细胞培养液PGE2 合成水平在 9h时抑制率为6 3.9% ;COX-2蛋白表达在 12h和 2 4h时抑制率分别为 4 8%和 10 0 %。结论苦参碱具有选择抑制HT-2 9细胞COX-2的基因转录、蛋白表达和功能活性等作用 ,在一定浓度和时间范围内 。

戊地昔布对人结肠癌HT-29细胞凋亡的影响

目的观察戊地昔布(Valdecoxib)对COX-2高表达的人结肠癌HT-29细胞凋亡的影响。方法将体外培养HT-29细胞分为正常组(C)、药物处理组(V)及溶剂对照组(S)。采用流式细胞术检测细胞凋亡,Western blot检测COX-2、caspase-3、cleaved caspase-3、Bcl-2、p38 MAPK、p-p38MAPK。结果与正常组相比,药物处理组细胞凋亡明显增加(P<0.05),cleaved caspase-3和p-p38MAPK表达增高,Bax/Bcl-2比率明显升高(P<0.05)。Valdecoxib干预能够显著促进HT-29细胞凋亡,上调cleaved caspase-3和p-p38 MAPK的表达,增加Bax/Bcl-2比率。结论 COX-2选择性抑制剂Valdecoxib能够促进HT-29细胞凋亡部分可能是通过激活p38MAPK信号通路而实现的。

扶正解毒祛瘀方联合奥沙利铂对人结肠癌HT-29细胞增殖与凋亡的影响及机制研究

目的:研究扶正解毒祛瘀方(简称"扶正方")联合奥沙利铂(L-OHP)对人结肠癌HT-29细胞增殖与凋亡的影响及机制。方法:将HT-29细胞分为空白对照组(不加药物)、扶正方组(1 000 mg/L)、L-OHP组(31.25 mg/L)和联合用药组(1 000 mg/L扶正方+31.25 mg/L L-OHP)。加入相应药物作用48 h后,采用MTT法检测细胞增殖情况,倒置显微镜下观察细胞形态的改变,流式细胞术检测细胞周期和凋亡率,实时荧光定量聚合酶链式反应(q RT-PCR)法检测细胞中促凋亡基因Bax、抑凋亡基因Bcl-2 m RNA的表达,Western blot法检测细胞中Bax、Bcl-2蛋白的表达。结果:与空白对照组比较,L-OHP组和联合用药组细胞增殖均受到抑制、S期和G_2/M期细胞比例升高、G_0/G_1期细胞比例降低(P<0.05),L-OHP组、扶正方组和联合用药组细胞凋亡率升高、细胞中Bax m RNA及蛋白的表达上调、细胞中Bcl-2 m RNA的表达下调(P<0.05),且联合用组变化较两药单用组更明显(P<0.05)。结论:扶正方与L-OHP联合应用可抑制HT-29细胞的增殖、促进细胞凋亡,且作用优于两药单用;其机制可能与上调细胞中Bax基因与蛋白表达、下调细胞中Bcl-2基因表达有关。

人参皂苷Rg3对HT-29细胞株MMP-1表达和迁移能力的影响

目的:研究人参皂苷Rg3对结肠癌细胞株HT-29基质金属蛋白酶-1(MMP-1)表达和细胞迁移能力的影响。方法:体外培养HT-29细胞,分为人参皂苷Rg3高剂量组(100μg/mL)、中剂量组(50μg/mL)、低剂量组(25μg/mL)和空白对照组,培养HT-29细胞24、48、72h,RT-PCR法测MMP-1 mRNA表达。利用划痕实验观察Rg3对HT-29细胞迁移能力的影响。结果:24h高剂量组与对照组相比,有显著的统计学差异(P<0.01);48h低、中、高剂量组与对照组相比均有显著的统计学差异(P<0.05、P<0.01、P<0.01);72h低、中、高剂量组与对照组相比均有显著的统计学差异(P<0.01、P<0.01、P<0.01)。划痕实验中空白对照组过河时间为(47.33±2.49)h,低、中、高剂量组过河时间分别为(55.33±2.49)h(P<0.01)、(64.00±1.63)h(P<0.01)和(73.33±1.89)h(P<0.01)。结论:人参皂苷Rg3能抑制HT-29细胞MMP-1的表达和抑制HT-29细胞的迁移能力,并且随着药物浓度的增加及时间的延长,抑制作用增强。

人结直肠癌耐药细胞株HT-29/CPT-11的构建及其生物学特性探讨

目的:建立耐伊立替康(CPT-11)的人结直肠癌细胞株(HT-29/CPT-11),并研究其生物学特性。方法:采用药物浓度梯度递增间歇诱导法建立人结直肠癌耐药株HT-29/CPT-11;CCK-8法检测CPT-11对亲本细胞HT-29和耐药细胞株HT-29/CPT-11细胞的半数抑制率(IC50);绘制细胞生长曲线,并计算细胞倍增时间;流式细胞术分析细胞周期分布;RT-PCR检测HT-29/CPT-11和HT-29细胞MDR-1 mRNA的表达。结果:(1)成功建立人结直肠癌耐药细胞株HT-29/CPT-11,耐药指数为6.51。(2)HT-29/CPT-11耐药细胞株倍增时间较原代细胞HT-29延长[分别为(41.29±1.69)h和(27.12±2.73)h,P<0.05]。(3)流式细胞术检测细胞周期结果显示,耐药细胞株HT-29/CPT-11 G1期细胞数目增加,S期细胞数目减少(P<0.05)。(4)耐药细胞HT-29/CPT-11的MDR-1 mRNA表达水平明显高于亲本细胞株HT-29,分别为1.086±0.054和0.416±0.02(P<0.05)。结论:成功构建了人结直肠癌耐药细胞株HT-29/CPT-11,为下一步研究耐药机制奠定实验基础。