Relationship between Fas/ FasL expression and apoptosis of colon adenocarcinoma cell lines

INTRODUCTIONFas/ FasL system has been identified as a keymediator of apoptosis in tumor cells[1-4]. Theoccurrence and development of neoplasm are closelyrelated to apoptosis[5-7] Most chemotherapeuticdrugs kill cancer cells mainly by inducingapoptosis[8-14].'

Paclitaxel induces apoptosis in human gastric carcinoma cells

AIM;To investigate the apoptosis in gastric cancer cells induced by paclitaxel,and the relation between this apoptosis and expression of Bcl-2 and Bax. METHODS:In in vitro experiments,MTT assay was used to determine the cell growth inhibitory rate.Transmission electron microscope and TUNEL staining method were used to quantitatively and qualitively detect the apoptosis status of gastric cancer cell line SGC-7901 before and after the paclitaxel treatment.Immunohistochemical staining was used to detect the expression of apoptosis-regulated gene Bcl-2 and Bax. RESULTS:Paclitaxel inhibited the growth of gastric cancer cell line SGC-7901 in a dose-and time-dependent manner. Paclitaxel induced SGC-7901 cells to undergo apoptosis with typically apoptotic characteristics,including morphological changes of chromatin condensation,chromatin crescent formation,nucleus fragmentation and apoptotic body formation.Paclitaxel could reduce the expression of apoptosis-regulated gene Bcl-2,and improve the expression of apoptosis-regulated gene Bax. CONCLUSION:Paclitaxel is able to induce the apoptosis in gastric cancer.This apoptosis may be mediated by down- expression of apoptosis-regulated gene Bcl-2 and up- expression of apoptosis-regulated gene Bax.

Effect of heparin on apoptosis in human nasopharyngeal carcinoma CNE2 cells

In order to study the mechanism of the effect of heparin on apoptosis in carcinoma cells, the nasopharyngeal carcinoma cell line CNE2 was used to identify the effect of heparin on apoptosis associated with the expression of c-myc, bax, bcl-2 proteins by use of Hoechst 33258 staining, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL), agarose gel electrophoresis, and flow cytometry, as well as Western blot analysis. The results showed that heparin induced apoptosis of CNE2 cells including the morphologic changes such as reduction in the volume, and the nuclear chromatin condensation, as well as the 'ladder pattern' revealed by agarose gel electrophoresis of DNA in a concentration-dependent manner. The number of TUNEL-positive cells was dramatically increased to 33.6+/-1.2% from 2.8+/-0.3% by treatment with heparin in different concentrations (10 to approximately 40 kU/L). The apoptotic index was increased to 32.5% from 3.5% by detecting SubG1 peaks on flow cytometry. Western blot analysis showed that levels of bcl-2, bax and c-myc were significantly overexpressed by treatment with the increase of heparin concentrations. These results suggest that heparin induces apoptosis of CNE2 cells, which may be regulated by differential expression of apoptosis-related genes.

Curcumin induces the expression of NF-κB and Bcl-2/Bax in human renal cell carcinoma cell line ACHN

Objective： To explore the in vitro effects of curcumin on the proliferation and apoptosis of the human renal cell carcinoma cell line ACHN, and to investigate its mechanisms of action. Methods： The human renal cell carcinoma cell line ACHN was treated with different concentrations of curcumin for 24 h. The MTT assay was used to evaluate the cytotoxic effects of curcumin and flow cytometry was utilized to observe and detect the apoptosis of ACHN cells induced by curcumin. The expression levels of Bcl-2, Bax and NF-κBP65 mRNA were evaluated by Reverse Transcription-Polymerase Chain Reaction （RT-PCR）, while the expression of Bcl- 2, Bax, NF-κBP65 and IκB proteins was evaluated by Western blot. Results： The concentrations of curcumin used significantly inhibited the proliferation of ACHN human renal cell carcinoma cells in vitro in a dose and time-dependent manner （Ftime=5.55, P 〈 0.05; Fdose=110.05, P 〈 0.05）. Obvious apoptosis of cells treated with different concentrations of curcumin could be observed by FCM. Compared with the control group, the apoptosis rates of curcumin-treated cells were markedly increased （F=96.35, P 〈 0.05）. Lower dose of curcumin significantly induced the apoptosis of ACHN cells. With intervention of different concentrations of curcumin （0, 10, 20 and 40 μmol/L） for 24 h, the expression levels of Bcl-2 and NF-κBP65 mRNA in ACHN cells were decreased while the expression level of Bax mRNA was increased （P 〈 0.05）, and Bcl-2, and NF-κBP65 protein decreased, while Bax and IκB protein increased compared with those in the untreated group. Conclusion： Curcumin inhibited proliferation and increased apoptosis of the human renal cell carcinoma cell line ACHN. These curcumin effects appear to involve up-regulating IκB, down-regulating NF-κB, and regulating the expression of the apoptosis genes Bcl-2/Bax.

Effect of Nimesulide on proliferation and apoptosis of human hepatoma SMMC-7721 cells

AIM: Cyclooxygenase-2 (COX-2) has been suggested to be associated with carcinogenesis. We sought to investigate the effect of the selective COX-2 inhibitor, Nimesulide on proliferation and apoptosis of SMMC-7721 human hepatoma cells.METHODS: This study was carried out on the culture of hepatic carcinoma SMMC-7721 cell line. Various concentrations of Nimesulide (0, 200 micromol/L, 300 micromol/L, 400 micromol/L) were added and incubated. Cell proliferation was detected with MTT colorimetric assay, cell apoptosis by electron microscopy, flow cytometry and TUNEL.RESULTS: Nimesulide could significantly inhibit SMMC-7721 cells proliferation dose-dependent and in a dependent manner compared with that of the control group. The duration lowest inhibition rate produced by Nimesulide in SMMC-7721 cells was 19.06%, the highest inhibition rate was 58.49%. After incubation with Nimesulide for 72 h, the most highest apoptosis rate and apoptosis index of SMMC-7721 cells comparing with those of the control were 21.20%+/-1.62% vs 2.24%+/-0.26% and 21.23+/-1.78 vs 2.01+/-0.23 (P【0.05). CONCLUSION:The selective COX-2 inhibitor, Nimesulide can inhibit the proliferation of SMMC-7721 cells and increase apoptosis rate and apoptosis index of SMMC-7721 cells. The apoptosis rate and the apoptosis index are dose-dependent. Under electron microscope SMMC-7721 cells incubated with 300 micromol and 400 micromol Nimesulide show apoptotic characteristics. With the clarification of the mechanism of selective COX-2 inhibitors, These COX-2 selective inhibitors can become the choice of prevention and treatment of cancers.

Growth inhibition and apoptosis induction Sulindac on Human gastric cancer cells

AIM: To evaluate the effects of sulindac in inducing growth inhibition and apoptosis of human gastric cancer cells in comparison with human hepatocellular carcinoma (HCC) cells. METHODS: The human gastric cancer cell lines MKN45 and MKN28 and human hepatocellular carcinoma cell lines HepG(2) and SMMC7721 were used for the study. Anti-proliferative effect was measured by MTT assay, and apoptosis was determined by Hoechst-33258 staining, electronography and DNA fragmentation. The protein of cyclooxygenase-2 (COX-2) and Bcl-2 were detected by Western dot blotting. RESULTS: Sulindac could initiate growth inhibition and apoptosis of MKN45, MKN28, HepG(2) and SMMC7721 cells in a dose-and time-dependent manner. Growth inhibitory activity and apoptosis were more sensitive in HepG(2) cells than in SMMC7721 cells, MKN45 and MKN28 cells. After 24 hours incubation with sulindac at 2mmol x L(-1) and 4mmol x L(-1), the level of COX-2 and Bcl-2 protein were lowered in MKN45, SMMC7721 and HepG(2) cells but not in MKN28 cells. CONCLUSION: Sulindac could inhibit the growth of gastric cancer cells and HCC cells effectively in vitro by apoptosis induction, which was associated with regression of COX-2 and Bcl-2 expression. The growth inhibition and apoptosis of HCC cells were greater than that of human gastric cancer cells. The different effects of apoptosis in gastric cancer cells may be related to the differentiation of the cells.

Killing effect of TNF-related apoptosis inducing ligand regulated by tetracycline on gastric cancer cell line NCI-N87

AIM: To clone the cDNA fragment of human TRAIL (TNF-related apoptosis inducing ligand) into a tetracycline-regulated gene expression system, the RevTet-On system, transduce expression vectors into a gastric carcinoma cell line-NCI-N87 and examine the effects of controlled expression of TRAIL in vitro on the gastric carcinoma cells. METHODS: The full-length cDNA of TRAIL was inserted into a vector under the control of the tetracycline-responsive element (TRE) to obtain the plasmid pRevTRE-TRAIL, which was transfected into a packaging cell line PT67. In addition, vector pRev-Tet On and pRevTRE were also transfected into PT67 separately. After hygromycin and G418 selection, the viral titer was determined. The medium containing retroviral vectors was collected and used to transduce a gastric carcinoma cell line NCI-N87. The resulting cell line NCI-N87-Tet On TRE-TRAIL and a control cell line, NCI-N87 Tet On-TRE, were established. TRAIL expression in the cell line was induced by incubating cells with doxycycline (Dox), which is a tetracycline analogue. The killing effect on gastric carcinoma cells was analyzed after induction. RESULTS: The recombinant plasmid pRev-TRE-TRAIL was constructed. After hygromycin or G418 selection, the producer cell lines PT67-TRE, PT67-TRE-TRAIL and PT67-Tet On were obtained,with titers of about 10(8)CFU.L(-1). By transducing NCI-N87 cells with retroviral vectors from these cell lines, stable cell lines NCI-N87-Tet-On TRE-TRAIL (NN3T) and control cell line NCI-N87-Tet-On-TRE (NN2T) were established. The growth curves of the selected cell lines were the same with the wild type NCI-N87. When Dox was added, cell death was obvious in the test groups (29%-77%), whereas no difference was observed in control and wild type cell lines. With the addition of a medium from the test group, human leukemia cell line Jurkat was activated till death (83%), indicating the secretion of active TRAIL proteins from the test cells to the medium. CONCLUSION: With the use of the RevTet-On system, a regulated expression system for TRAIL was constructed. Using this system, the selected killing effect of TRAIL on gastric carcinoma cell line NCI-N87 could be observed.

Curcumin联合放射对人结肠癌细胞株HT29的增殖抑制作用研究

目的探讨姜黄素(Curcumin,Cur)在放射线诱导的HT29细胞增殖及凋亡中的作用。方法常规培养HT29细胞,经6 Gy放射线照射和(或)Cur处理24 h后,通过MTT比色法分析空白对照组、6 Gy单独照射组及联合处理组(5μmol/L姜黄素+6 Gy组、10μmol/L姜黄素+6 Gy组、20μmol/L姜黄素+6 Gy组)HT29细胞增殖率,采用流式细胞术Annexin V-FITC/PI双染法分析细胞凋亡率,通过Elisa实验评价细胞中半胱氨酸蛋白酶Caspase-3、Caspase-6和Caspase-9活性。结果 Cur和6 Gy联合处理组的细胞增殖率明显高于空白对照组和6 Gy单独照射组(P<0.05),细胞凋亡率亦显著高于空白对照组和6 Gy单独照射组(P<0.01);同时,Cur和6 Gy联合处理组细胞中Caspase-3、Caspase-6和Caspase-9活性亦明显高于对照组和6 Gy单独照射组(P<0.05)。结论 Cur可通过促进细胞凋亡相关因子活性,进而诱导HT29细胞凋亡,抑制其增殖,发挥HT29细胞对放射线的增敏作用,此可为结肠癌放射治疗的临床研究提供新的思路。

Blockage of IGF-1R signaling sensitizes urinary bladder cancer cells to mitomycin-mediated cytotoxicity

A major problem which is poorly understood in the management of bladder cancer is low sensitivity to chemotherapy and high recurrence after transurethral resection. Insulin-like growth factor 1 receptor (IGF-1R) signaling plays a very important role in progression, invasion and metastasis of bladder cancer cells. In this study, we investigated whether IGF-1R was involved in the growth stimulating activity and drug resistance of bladder cancer cells. The results showed: The mRNAs of IGF-1, IGF-2 and IGF-1R were strongly expressed in serum-free cultured T24 cell line, whereas normal urothelial cells did not express these factors/receptors or only in trace levels; T24 cell responded far better to growth stimulation by IGF-1 than did normal urothelial cells; blockage of IGF1R by antisense oligodeoxynucleotide (ODN) significantly inhibited the growth of T24 cell and enhanced sensitivity and apoptosis of T24 cells to mitomycin (MMC). These results suggested that blockage of IGF-IR signaling might potentially contribute to the treatment of bladder cancer cells which are insensitive to chemotherapy.

探讨姜黄素通过NF-κB对鼻咽癌CNE-2Z细胞的生长抑制作用、诱导凋亡作用及其机制研究

目的:探讨姜黄素通过NF-κB对鼻咽癌CNE-2Z细胞增殖的影响。方法:MTT法测定姜黄素对鼻咽癌CNE-2Z细胞增殖的影响,采用流式细胞仪测定姜黄素不同浓度下的CNE-2Z细胞凋亡情况,Western Blot测定NF-κB蛋白的表达。结果:姜黄素能影响CNE-2Z细胞的NF-κB蛋白表达,使NF-κB蛋白表达水平降低,说明姜黄素对CNE-2Z的增殖和转移有一定的影响。姜黄素对CNE-2Z的作用效果受作用时间和浓度影响,其对CNE-2Z细胞24 h的IC50数值为(43.514~45.435)μmol/L,48 h的IC50数值为(8.366~13.11)μmol/L,72 h的IC50数值为(5.658~8.469)μmol/L。结论:姜黄素能够通过NF-κB蛋白的表达,来抑制鼻咽癌CNE-2Z细胞增殖与侵袭。姜黄素浓度越高,作用时间越长,CNE-2Z细胞增殖抑制效果越好。

基于生物信息学和体外实验探讨紫草素潜在的抗肿瘤机制

目的:紫草素(SHK),一种紫草根部的萘醌类活性成分,具有抗肿瘤活性。本研究通过生物信息学方法和细胞实验,探索SHK在肝细胞肝癌(LIHC)、前列腺腺癌(PRAD)和结肠腺癌(COAD)中的新靶点。方法:通过人类基因数据库(GeneCard)及癌症基因图谱(TCGA)获得SHK与3种癌症的交集基因,并进行基因本体(GO)和京都基因和基因组百科全书(KEGG)富集分析、蛋白质-蛋白质相互作用(PPT)网络构建等。体外实验检测SHK对人肝癌细胞(HepG2)、人前列腺癌细胞(LNCaP C4-2)和人结肠癌细胞(HT-29)的抑制作用,并分析SHK对细胞凋亡及预测靶点基因表达的影响。结果:SHK显著抑制3种癌细胞增殖并通过调节周期素依赖性激酶抑制因子1A(CDKN1A)等基因的表达实现抗肿瘤作用,且与生物信息学预测结果一致。此外,Kaplan-Meier生存曲线进一步表明CDKN1A等是SHK影响癌症患者生存的重要靶点;CDKN1A和B淋巴细胞瘤-2(BCL-2)是SHK抑制肿瘤细胞增殖和侵袭的核心靶点。结论:SHK可通过人体抑癌基因(P53)/CDKN1A和BCL-2/BCL-2关联X蛋白(BAX)通路诱导癌细胞凋亡。本研究报道了SHK抑制肿瘤的作用靶点及潜在机制,为含SHK的中草药作为抗肿瘤的潜在药物提供了初步依据。

姜黄素对小鼠肝癌细胞体外增殖和凋亡的影响

目的探讨姜黄素对小鼠肝癌Hepa1-6细胞体外增殖和凋亡的影响。方法取处于对数生长期的Hepa1-6细胞,随机分为对照组、10μmol/L组、20μmol/L组和40μmol/L组,分别采用0、10、20、40μmol/L的姜黄素进行干预,通过MTT法检测细胞增殖,流式细胞术检测细胞凋亡。RT-qPCR法检测Hepa1-6细胞中凋亡相关分子Bcl-2和Caspase-3及Toll样受体2(TLR2)、IFN-α、IFN-β基因表达。ELISA法检测Hepa1-6细胞培养上清IFN-Ⅰ。对照组、40μmol/L组中Hepa1-6细胞分别与CD4+T细胞、CD8+T细胞和NK细胞共孵育,流式细胞术检测CD4+T细胞、CD8+T细胞和NK细胞CD69表达。结果10、20、40μmol/L组Hepa1-6细胞增殖抑制率呈剂量依赖性增加,抑制率依次为(36.45±2.11)%、(46.40±2.08)%、(82.16±3.32)%,与对照组比较差异均有统计学意义(P均<0.05);10、20和40μmol/L组Hepa1-6细胞凋亡比例分别为10.47%、26.66%和49.81%,与对照组比较差异均有统计学意义(P均<0.01)。RT-qPCR结果显示,10、20和40μmol/L组中抗凋亡基因Bcl-2转录水平分别是对照组的(0.77±0.06)倍、(0.44±0.06)倍和(0.25±0.08)倍,与对照组比较差异均有统计学意义(P均<0.01);同时,促凋亡基因Caspase-3表达增高,10、20和40μmol/L组中促凋亡基因Caspase-3转录水平分别是对照组的(1.73±0.31)倍、(2.52±0.45)倍和(3.25±0.20)倍,与对照组比较差异均有统计学意义(P均<0.01)。随姜黄素浓度的增加,TLR2转录水平逐渐升高,10、20和40μmol/L组TLR2转录水平分别是对照组的(3.56±0.59)倍、(4.93±0.04)倍和(6.60±0.47)倍,与对照组比较差异均有统计学意义(P均<0.05);10、20和40μmol/L组IFN-α转录水平升高,分别为对照组的(4.21±0.22)倍、(5.54±0.39)倍和(8.05±0.93)倍,与对照组比较差异均有统计学意义(P均<0.05);IFN-β转录水平分别为对照组的(3.08±0.51)倍、(5.31±0.55)倍和(8.35±0.59)倍,与对照组比较差异均有统计学意义(P均<0.01)。10、20和40μmol/L组细胞分泌IFN-α水平分别为(57.00±8.8)、(82.47±4.42)、(100.37±8.99)pg/mL,对照组为(36.26±6.12)pg/mL,10、20和40μmol/L组细胞分泌IFN-α水平高于对照组(P均<0.01);10、20和40μmol/L组细胞分泌IFN-β水平分别为(60.67±6.81)、(91.33±5.51)、(144.00±10.15)pg/mL,对照组为(44.67±1.15)pg/mL,10、20和40μmol/L组细胞分泌IFN-β水平高于对照组(P均<0.01)。对照组CD4+T细胞、CD8+T细胞和NK细胞表达CD69水平分别为(24.53±1.39)%、(23.40±2.32)%、(32.33±3.08)%,40μmol/L组CD4+T细胞、CD8+T细胞和NK细胞表达CD69水平分别为(39.90±3.51)%、(31.47±3.88)%、(50.83±4.74)%,对照组与40μmol/L组CD4+T细胞、CD8+T细胞和NK细胞CD69水平比较差异均有统计学意义(P均<0.05)。结论姜黄素通过调控TLR2分子表达,促进IFN-Ⅰ分泌,从而抑制肝癌细胞增殖,促进肝癌细胞凋亡,同时促进免疫细胞活化。

miR-193b-3p、PAK4过表达对人结肠癌细胞增殖凋亡和迁移侵袭的影响及靶向关系

目的观察微小核糖核酸193b-3p(miR-193b-3p)、P21活化蛋白激酶4(PAK4)过表达对人结肠癌细胞系HCT116细胞增殖凋亡和迁移侵袭的影响,并验证两者的靶向关系。方法体外培养人正常结肠黏膜上皮细胞FHC及人结肠癌细胞HCT116、SW480、LoVo,采用RT-PCR检测各细胞miR-193b-3p、P21活化蛋白激酶4(PAK4)mRNA。取生长状态良好的对数生长期HCT116细胞,分为4组,miR-NC组转染miRNA阴性对照、miR-193b-3p组转染miR-193b-3p模拟物、miR-193b-3p+PAK4-NC组转染miR-193b-3p模拟物+P21活化蛋白激酶4(PAK4)空载体、miR-193b-3p+PAK4组转染miR-193b-3p模拟物+PAK4过表达载体,分别采用RT-PCR、CCK-8试验、流式细胞术、Transwell实验检测各组细胞miR-193b-3p、PAK4 mRNA表达及增殖活性、凋亡率、迁移细胞数、侵袭细胞数。采用生物信息学软件Target Scan7.2预测miR-193b-3p与PAK4的靶向关系,并采用双荧光素酶报告基因实验进行验证。结果过表达miR-193b-3p后,HCT116细胞增殖活性、迁移及侵袭能力均明显下降,凋亡率明显升高,PAK4 mRNA表达水平降低(P均<0.05)。上调PAK4表达能够部分逆转过表达miR-193b-3p对HCT116细胞增殖活性、迁移及侵袭能力的抑制及对凋亡的促进作用(P均<0.05)。双荧光素酶报告基因显示miR-193b-3p能靶向结合PAK4的3'UTR区,抑制其荧光素酶活性(P<0.05)。结论miR-193b-3p过表达可抑制HCT116细胞增殖、迁移及侵袭,并促进其凋亡,miR-193b-3p与PAK4存在靶向关系。

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。

姜黄素诱导Lovo细胞凋亡

目的旨在探讨姜黄素体外抗人结肠癌Ｌｏｖｏ细胞生长的作用。方法采用口丫啶橙荧光染色、透射电镜观察、流式细胞仪测定及ＤＮＡ凝胶电泳等技术研究姜黄素诱导肿瘤细胞凋亡的作用。结果经姜黄素２０μＭ处理２４ｈ肿瘤细胞即可发生凋亡，凋亡率达３２．６％。ＤＮＡ凝胶电泳产生特征性ＤＮＡ梯形带。口丫啶橙荧光染色和透射电镜观察证实肿瘤细胞形态呈凋亡特征性改变。结论姜黄素可诱导肿瘤细胞凋亡。

姜黄素阻断NF-κB信号通路促进食管鳞癌细胞凋亡的体外研究

背景与目的:活化的核转录因子-kappa B(nuclear factor-kappa B,NF-κB)信号通路参与调控多种与炎症、抗凋亡、肿瘤形成和转化有关的基因表达。但在食管鳞癌中的作用尚不清楚。姜黄素具有抗感染、抗氧化等多种药理作用。本研究将探讨姜黄素是否能够通过阻断NF-κB信号通路对食管鳞癌细胞增殖、抗凋亡产生影响。方法:Western blot法检测EC9706和Eca109细胞中加入姜黄素(50μmol/L)培养不同时间后,pIκBα和抗凋亡蛋白Bcl-2的表达情况。在EC9706和Eca109细胞中加入姜黄素培养72h,流式细胞仪检测凋亡细胞情况。MTT法检测姜黄素单独或与5-FU联合对细胞增殖的影响。结果:Western blot的结果显示,在姜黄素作用下EC9706和Eca109细胞中pIκBα和Bcl-2蛋白的表达水平随着时间的延长逐渐下降。在单独使用姜黄素后,就可促进EC9706和Eca109细胞的凋亡(P<0.05);当与5-FU联合使用时,可明显提高EC9706和Eca109细胞对化疗药物的敏感性,凋亡细胞显著增加(P<0.05)。姜黄素与5-FU联合应用48h和72h,可明显抑制EC9706和Eca109细胞的增殖,与单独使用姜黄素或5-FU组相比,细胞存活率显著降低,差异有统计学意义(P<0.05)。结论:姜黄素可以通过抑制IκBα的磷酸化阻断NF-κB信号通路,促进细胞凋亡,抑制细胞增殖,增加细胞对5-FU的敏感性。

姜黄素对人肾癌ACHN细胞放射的增敏作用及其机制

目的研究姜黄素对人肾癌ACHN细胞放射的增敏作用,并探讨其作用机制。方法以人肾癌ACHN细胞为研究对象,MTT比色法检测姜黄素对人肾癌ACHN细胞增殖的抑制作用;克隆形成实验检测姜黄素对ACHN细胞的放射增敏作用;流式细胞术检测ACHN细胞周期分布;RT-PCR检测ACHN细胞Bcl-2、Bax、NF-κBP65和DNA-PKcs mRNA的表达。结果姜黄素对人肾癌ACHN细胞生长具有明显的抑制作用,且呈现剂量和时间效应。10μmol/L姜黄素可降低放射后人肾癌ACHN细胞的细胞存活分数(P<0.05),有放射增敏作用,放射增敏比SERDq为2.36。药物+放射组ACHN细胞周期阻滞在放射敏感时相G2/M期。与放射组相比,药物+放射组Bcl-2、NF-κBP65和DNA-PKcs mRNA水平明显降低(P<0.05)。结论姜黄素对人肾癌ACHN细胞具有放射增敏作用,其作用机制可能与其抑制ACHN细胞NF-κB表达,下调Bcl-2/Bax比例,抑制DNA损伤修复,改变ACHN细胞周期分布有关。

大蒜素对结肠癌LoVo细胞增殖的影响

目的:观察大蒜素对结肠癌细胞LoVo生长、细胞凋亡及细胞周期的影响。方法:不同浓度的大蒜素作用于体外培养的LoVo细胞,倒置显微镜下观察LoVo细胞的形态学变化,采用MTT法检测大蒜素对LoVo细胞增殖抑制能力,An-nexinV-FITC标记流式细胞术检测大蒜素对LoVo细胞的凋亡抑制率,流式细胞术检测大蒜素对LoVo细胞周期影响。结果:大蒜素可抑制人结肠癌LoVo细胞增殖,具有明显量效和时间依赖性,24、48和72h大蒜素抑制LoVo细胞的IC50分别为32.23、10.74和6.58μg/ml;大蒜素能够诱导LoVo细胞凋亡,作用24h其诱导凋亡率随着药物浓度的递增具有增高趋势,作用48h其诱导凋亡作用峰值浓度为8μg/ml,后再继续增加浓度凋亡率反而下降;大蒜素作用LoVo细胞24h后,大蒜素浓度低于4μg/ml时,LoVo细胞周期被阻滞于G2/M;而高于4μg/ml时,细胞周期被阻滞于G2/M和G1期。结论:大蒜素能够诱导LoVo细胞凋亡,阻滞细胞周期,抑制细胞增殖。

姜黄素诱导肿瘤细胞凋亡的实验研究

目的:探讨姜黄素诱导HepG2细胞凋亡的作用机制。方法:应用形态学方法、AnnexinV荧光染色和流式细胞仪(FCM)检测HepG2细胞凋亡的发生,应用RT-PCR检测凋亡相关基因P53、bcl-2和Fas的变化。结果:姜黄素对HepG2细胞的生长有明显的抑制作用,并诱导肿瘤细胞发生凋亡。凋亡细胞表现为细胞固缩,核染色质碎裂;流式细胞仪检测凋亡率为11.7%,细胞停在G1和G2期。AnnexinV标记的方法检测凋亡时发现,坏死与凋亡共存。在姜黄素诱导HepG2细胞凋亡过程中,凋亡相关基因Fas转录水平比用药前增强。结论:凋亡为姜黄素抑癌的机制之一,姜黄素诱导HepG2细胞凋亡可能与P53、bcl-2和Fas基因表达有关。

灵芝多糖联合5-FU对人结肠癌HCT-116细胞增殖及凋亡的影响

目的:探讨灵芝多糖(GLP)联合5-氟尿嘧啶(5-FU)对人结肠癌HCT-116细胞增殖抑制及凋亡的影响。方法:采用MTT法测定单独和联用GLP与5-FU对人结肠癌HCT-116细胞的协同抑制作用,应用联合指数法分析两药物之间相互作用,Hoechst33258荧光染色观察细胞的形态学改变,碘化吡啶(PI)标记流式细胞术(FCM)检测GLP联合5-FU对HCT-116细胞周期和凋亡抑制率的变化。结果:MTT法测定结果显示GLP和5-FU单独用药均能显著抑制HCT-116细胞增殖。GLP(>659μg/mL)联用5-FU(>1.6μg/mL)联用呈协同效应(CI<1),与5-FU单独用药组相比有极显著差异(P<0.01),并呈时间依赖性。给药48h后,Hoechst33258荧光染色可见典型的凋亡形态学特征。FCM检测凋亡显示两药联合作用24h后,5mg/mL GLP联合50μg/mL 5-FU的凋亡率为36.14%,高于5-FU(50μg/mL)单独用药组(26.07%);1.25mg/mL GLP联合12.5μg/mL 5-FU、2.5mg/mL GLP联合25μg/mL 5-FU、5mg/mL GLP联合50μg/mL5-FU作用48h后,凋亡率分别为20.95%、32.87%、30.01%,均高于5-FU(50μg/mL)单独用药组(14.51%)。联合用药组可使HCT-116细胞阻滞于S期。结论:较高质量浓度的GLP与5-FU联用具有协同抑制人结肠癌细胞株HCT-116细胞增殖,诱导细胞凋亡,阻滞细胞周期作用。