Norsolorinic acid inhibits proliferation of T24 human bladder cancer cells by arresting the cell cycle at the G0/G1 phase and inducing a Fas/membrane-bound Fas ligand-mediated apoptotic pathway

1. Norsolorinic acid, isolated from Aspergillus nidulans, has been shown to have antiproliferative activity in T24 human bladder cancer cells by arresting the cell cycle at the G(0)/G(1) phase and inducing apoptosis. The aim of the present study was to investigate the antiproliferative activity of norsolorinic acid in T24 human bladder cancer cells. 2. The effects of norsolorinic acid (1, 5, 10 and 20 micromol/L) on the proliferation of T24 cells and on the distribution of cells within different phases of the cell cycle were investigated indirectly using an XTT assay and a flow cytometer, respectively. Factors affecting the cell cycle and apoptosis, including p53, p21, Fas receptor, Fas ligand (FasL) and caspase 8 activity, were examined using ELISA. 3. The results showed that norsolorinic acid inhibited proliferation of T24 cells in a dose-dependent manner, with an IC(50) of 10.5 micromol/L. The effect involved the induction of cell cycle arrest at the G(0)/G(1) phase and apoptosis. 4. These results demonstrate that G(0)/G(1) phase arrest is due to increased expression of p21 in cells treated with norsolorinic acid (10 and 20 micromol/L) for 24 h. Moreover, enhanced Fas and membrane-bound Fas ligand (mFasL) may be responsible for the apoptotic effect of norsolorinic acid. Thus, the present study reports, for the first time, that induction of p21 and the Fas/mFas ligand apoptotic system may participate in the antiproliferative action of norsolorinic acid in T24 human bladder cancer cells.     

Induction of G(2)/M phase arrest and apoptosis by a new synthetic anti-cancer agent, DW2282, in promyelocytic leukemia (HL-60) cells.

We studied the effect of DW2282-,[(S)-(+)-4-phenyl-1-[N-(4-aminobenzoyl)-indoline-5-sulfonyl-4,5-dihydro-2-imidazolone].hydrochloride], a newly developed anti-cancer agent, on cell proliferation, cell cycle progression, and induction of apoptosis in human promyelocytic leukemia (HL-60) cells. DW2282, a diarylsulfonylurea compound, was cytotoxic to HL-60 cells, with an IC(50) of 1.0 microg/mL. Treatment with DW2282 fragmented DNA in a concentration- and time-dependent manner, suggesting that these cells underwent apoptosis. Flow cytometric analysis further confirmed that DW2282-treated HL-60 cells were hypodiploid, in terms of DNA content, and were arrested at the G(2)/M phase. The cell cycle arrest was reversible upon the removal of DW2282. HL-60 cells also underwent distinct morphological changes in response to DW2282 treatment, including the appearance of elongated cells with conical tails and other apoptotic characteristics. G(2)/M phase cell cycle arrest was accompanied by a decrease in the levels of cdc2, a protein that plays a critical role for progression through the G(2)/M phase. Treatment of HL-60 cells with DW2282 was also associated with decreased levels of the anti-apoptotic protein Bcl-2, activation of caspase-3, and proteolytic cleavage of poly(ADP-ribose) polymerase. Taken together, these results demonstrate that DW2282 dramatically suppressed HL-60 cell growth by inducing apoptosis after G(2)/M phase arrest. These findings are consistent with the possibility that G(2)/M phase arrest was mediated by the down-regulation of cdc2 levels in HL-60 cells. The data also suggest that DW2282 triggered apoptosis by decreasing Bcl-2 levels and activating caspase-3 protease. These results provide important new information towards understanding the mechanisms by which DW2282 and other diarylsulfonylureas mediate their therapeutic effects.     

苦参碱抑制人子宫内膜癌细胞增殖转移及机制研究

目的探讨苦参碱对人子宫内膜癌细胞增殖转移的抑制作用及机制。方法 MTT法检测苦参碱对人子宫内膜癌Ishikawa细胞株的抑制作用;流式细胞术观察对细胞周期的影响;ELISA法检测细胞培养上清液中炎性因子IL-8的浓度;Western印迹法检测经苦参碱干预该细胞48h后,NF-кB信号途径中p65的变化。结果苦参碱可显著抑制Ishikawa细胞生长,并呈时间和剂量依赖性。苦参碱使细胞阻滞于G0/G1期。细胞培养上清液中IL-8的浓度随着干预时间延长而减少(P<0.05)。苦参碱作用48h后,细胞NF-кBp65表达明显下降(P<0.05)。结论苦参碱具有抑制人子宫内膜癌Ishikawa细胞增殖的作用,使细胞阻滞于G0/G1期;抑制子宫内膜癌转移的作用,可能与抑制IL-8分泌及阻断NF-кB信号通路有关。     

Sorafenib alone or as combination therapy for growth control of cholangiocarcinoma

BACKGROUND/AIM: Treatment options of advanced cholangiocarcinoma (CC) are unsatisfactory and new therapeutic approaches are mandatory. Dysregulations of the mitogen-activated kinase (MAPK) pathway associated with proliferative advantages of tumors are commonly observed in CCs. The novel multi-kinase inhibitor sorafenib potently suppresses the growth of various cancers by inhibiting kinases of wild-type B-Raf, mutant(V559E)B-Raf and C-Raf but its effects on CC remains to be explored. We therefore studied the antineoplastic potency of sorafenib in human CC cells alone and in combination with conventional cytostatics or IGF-1R inhibition. METHODS AND RESULTS: Sorafenib treatment dose-dependently blocked growth-factor-induced activation of the MAPKP and inhibited the proliferation of EGI-1 and TFK-1 CC cells in a time- and dose-dependent manner. At least two mechanisms accounted for the effects observed: arrest at the G(1)/G(0)-transition of the cell cycle and induction of apoptosis. The cell cycle arrest was associated with upregulation of the cyclin-dependent kinase inhibitor p27(Kip1) and downregulation of cyclin D1. Combining sorafenib with doxorubicin or IGF-1R-inhibition resulted in (over)additive antiproliferative effects whereas co-application of sorafenib and the antimetabolites 5-FU or gemcitabine diminished the antineoplastic effects of the cytostatics. CONCLUSION: Our study demonstrates that the growth of human CC cells can be potently suppressed by sorafenib alone or in certain combination therapies and may provide a promising rationale for future in vivo evaluations and clinical trials.     

小鼠p27~(kip1)真核表达载体的构建及其对单个核细胞周期的影响

目的构建小鼠p27kip1真核表达载体,探讨其对单个核细胞生长情况和细胞周期的影响,为进一步研究p27kip1在疾病防治中的作用奠定基础。方法将小鼠p27kip1基因克隆至pcDNA3.0真核表达载体上,并经脂质体介导转染至小鼠单个核细胞中,应用MTT法和流式细胞仪分析转染细胞生长情况和细胞周期。结果经酶切分析和测序鉴定,成功构建了小鼠pcDNA3.0/p27kip1重组质粒;经pcDNA3.0/p27kip1转染的单个核细胞中p27蛋白表达增多,其生长增殖不仅受到明显抑制,而且处于G1/G0期的细胞明显增加,处于S期的细胞明显减少。结论构建的pcDNA3.0/p27kip1真核表达载体能够在单个核细胞中表达,且高表达的pcD-NA3.0/p27kip1可以通过抑制细胞周期的方式抑制单个核细胞的生长。     

薯蓣苷元诱导人黑素瘤细胞A375-S2凋亡依赖半胱天冬酶和MAPK途径

目的　研究薯蓣苷元诱导人黑素瘤细胞A375 S2凋亡的机制。方法　MTT法测定细胞生长抑制率及半胱天冬酶和有丝分裂原活化的蛋白激酶(MAPK)抑制剂对薯蓣苷元诱导细胞凋亡的影响。电镜观察细胞形态变化。流式细胞仪检测细胞凋亡及周期分布。用半胱天冬酶活力检测试剂盒测定半胱天冬酶活力。结果　薯蓣苷元抑制A375 S2细胞的生长呈时间 剂量依赖性。经薯蓣苷元处理后的A375 S2细胞表现出典型的凋亡特征 :细胞表面微绒毛消失、胞质空泡化、染色质浓集、边聚。流式细胞仪检测表明薯蓣苷元导致DNA片段化和细胞周期阻滞在G0 /G1期。半胱天冬酶家族抑制剂 (z VAD fmk )和p38MAPK抑制剂 (SB2 0 35 80 )可部分抑制薯蓣苷元诱导的A375 S2细胞凋亡。结论薯蓣苷元可诱导A375 S2细胞凋亡。其诱导凋亡作用与半胱天冬酶及MAPK的活化相关。     

β-榄香烯对肝癌细胞增殖及细胞周期的影响

目的观察β-榄香烯对体外培养肝癌细胞增殖以及细胞周期的影响。方法肝癌7402细胞体外培养,β-榄香烯干预;四甲基偶氮唑蓝(MTT)法检测β-榄香烯对细胞增殖的抑制作用;流式细胞仪检测细胞周期。结果肝癌7402细胞经过β-榄香烯干预,其存活率明显降低,并呈剂量依赖性。细胞周期检测结果显示,β-榄香烯干预后,进入S期和G2期细胞明显减少,G1期细胞增多,细胞周期被阻滞于G1期。结论β-榄香烯可明显抑制肝癌细胞的增殖及细胞周期,阻滞细胞从G1期进入S期。     

岩大戟内酯B通过阻断PI3K/Akt/NF-κB通路抑制结肠癌细胞的增殖和转移

目的:研究岩大戟内酯B(JB)对结肠癌HT-29细胞增殖和转移的抑制作用及其作用机制。方法:用不同浓度JB处理HT-29细胞,采用MTT法检测细胞增殖率;平板克隆实验检测细胞克隆形成率;流式细胞仪检测细胞周期变化;划痕实验分析细胞的迁移能力;Transwell小室实验研究细胞的侵袭能力;免疫荧光法和Western blotting法检测E-钙黏蛋白(E-cadherin)、N-钙黏蛋白(N-cadherin)、波形蛋白vimentin、锌指蛋白(Snail)1、Snail2、基质金属蛋白酶(MMP)-2和MMP-9蛋白的表达;Western blotting法检测p-PI3K、PI3K、p-Akt、Akt、NF-κB P65、p-NF-κB P65蛋白表达水平。100μg/L IGF-1组和100μg/L IGF-1+20μmol/L JB组分别处理HT-29细胞,Western blotting法检测PI3K/Akt/NF-κB通路相关蛋白表达变化。结果:JB抑制HT-29细胞增殖作用浓度依赖性,其作用24 h的IC 50为52.68μmol/L;JB呈浓度依赖性地降低HT-29细胞的克隆形成率(P<0.05);与对照组相比,JB处理后的HT-29细胞G0/G1期比例显著增高,S期细胞比例明显下降;JB可显著抑制HT-29细胞的体外迁移、侵袭能力(P<0.05);JB作用后的HT-29细胞E-cadherin蛋白水平升高,vimentin、Snail1、Snail2、N-cadherin、MMP-2、MMP-9、p-PI3K、p-Akt、p-NF-κB P65蛋白表达水平显著降低(P<0.05);IGF-1+JB组p-PI3K、p-Akt、与p-NF-κB P65蛋白的表达水平较IGF-1组显著下降(P<0.05)。结论:JB在体外能抑制HT-29细胞增殖,诱导细胞在G0/G1期阻滞,抑制HT-29迁移和侵袭,调控上皮-间质转化(EMT)及MMPs,其机制可能与阻断PI3K/Akt/NF-κB通路有关。     

Inhibitory effects of cancer cell proliferation by novel histone deacetylase inhibitors involve p21/WAF1 induction and G2/M arrest

Two compounds were synthesized which have a structural component other than those of our new series histone deacetylase (HDAC) inhibitors to determine the structure-activity relationship. It was also examined whether the inhibitory effects on cancer cell proliferation by HDAC inhibitors involve p21/WAF1 induction and G(1) or G(2)/M arrest in p53-mutated MG63 human osteosarcoma cells as do other HDAC inhibitors. It was demonstrated that inhibitors with the 2-naphthylcarbonyl group and hydroxamic acid at both termimal sides as well as the phenylene component at the center of molecule markedly induce the p21/WAF1 protein by stimulating p21/WAF1 gene promoter activity. Furthermore, cell cycle analysis revealed that these compounds arrest MG63 cells in the G(2)/M phase.     

Andrographolide isolated from Andrographis paniculata induces cell cycle arrest and mitochondrial-mediated apoptosis in human leukemic HL-60 cells

The in vitro cytotoxicities of the ethanol extract of Andrographis paniculata (APE) and its main diterpenoid components were evaluated in various cancer cells. APE was found to be significantly growth inhibitory to human acute myeloid leukemic HL-60 cells with an IC (50) value of 14.01 microg/mL after 24 h of treatment. Among the three main diterpenoids in A. paniculata, andrographolide exhibited the highest degree of cytotoxicity followed by deoxyandrographolide while neoandrographolide was the least effective. Laser confocal microscopy and gel electrophoresis studies revealed chromosomal DNA fragmentations suggesting the occurrence of apoptosis. An increase of G (0)/G (1) phase cells from 51.88 % to 78.69 % was noted after andrographolide treatment for 36 h. The G (0)/G (1) phase arrest and apoptosis were associated with disappearance of mitochondrial cytochrome c and increased expression of Bax but decreased expression of Bcl-2 proteins in the inhibited cells. Although the order of all these events has not been determined, it is concluded that APE and andrographolide induce cell cycle arrest and affect an intrinsic mitochondria-dependent pathway of apoptosis by regulating the expression of some pro-apoptotic markers in HL-60 cells.     

(-)-Syringaresinol inhibits proliferation of human promyelocytic HL-60 leukemia cells via G1 arrest and apoptosis

We examined the effect of (-)-syringaresinol, a furofuran-type lignan isolated from Daphne genkwa, on cell cycle regulation in HL-60 human promyelocytic leukemia cells in vitro. (-)-Syringaresinol decreased the viability of HL-60 cells by inducing G(1) arrest followed by apoptosis in a dose- and time-dependent manner. The G(0)/G(1) phase of the cell cycle is regulated by cyclin-dependent kinases (Cdk), cyclins and cyclin-dependent kinase inhibitors (Cdki). We show by western blot analysis, that the (-)-syringaresinol-induced G(1) arrest was mediated through the increased expression of Cdki proteins (p21(cip1/waf1) and p27(kip1)) with a simultaneous decrease in cdk2, cdk4, cdk6, cyclin D(1), cyclin D(2), and cyclin E expression. The induction of apoptosis after treatment with (-)-syringaresinol for 24 h was demonstrated by morphological changes, DNA fragmentation, altered ratio of Bax/Bcl-2, cleavage of poly(ADP-ribose) polymerase and flow cytometry analysis. (-)-Syringaresinol also induced cytochrome c release and activation of caspase-3 and caspase-9. To our knowledge, this is the first time that (-)-syringaresinol has been reported to potently inhibit the proliferation of human promyelocytic HL-60 cells through G(1) arrest and induction of apoptosis. These findings suggest that (-)-syringaresinol may be a potential chemotherapeutic agent for the treatment of cancer.     

戊地昔布对人胃癌细胞生长的抑制作用

目的　探讨选择性环氧化酶 2 (COX 2 )抑制剂戊地昔布对人胃癌BGC 82 3细胞的作用及其作用机制。方法　用MTT法检测戊地昔布对人胃癌BGC 82 3细胞生长的作用 ,用流氏细胞仪检测细胞凋亡和细胞周期分布 ,用激光共聚焦显微镜、透射电镜和DNA片段进一步检测细胞凋亡 ,用乳酸脱氢酶 (LDH)试剂盒测定BGC 82 3细胞的LDH含量。结果　戊地昔布 (2 5～ 4 0 0 μmol·L-1 )可时间和浓度依赖性抑制人胃癌BGC 82 3细胞的生长 ,作用 72h后 ,对细胞生长抑制率可达 2 4 0 %～ 92 0 % ,凋亡率由 (2 6± 0 7) %增加到 (7 6±1 5 ) %～ (1 6 5± 1 5 ) %。 1 0 0～ 4 0 0 μmol·L-1 也降低增殖指数 ,减少细胞周期S期细胞 ,增加G0 /G1 期细胞。随浓度增加 ,戊地昔布引起的LDH释放率有增加趋势 ,但只有 4 0 0μmol·L-1 戊地昔布可显著增加LDH释放率。结论　戊地昔布可通过诱导凋亡和细胞周期停滞而抑制人胃癌BGC 82 3细胞生长 ,4 0 0 μmol·L-1 戊地昔布抑制BGC 82 3细胞生长作用与细胞坏死有关     

吡格列酮对HepG2细胞增殖和凋亡的影响及机制研究

目的观察吡格列酮对体外培养的HepG2细胞增殖和凋亡的影响,并探讨其是否通过PPARγ依赖途径发挥上述药理作用。方法将不同浓度的吡格列酮作用于体外培养HepG2细胞,以MTT比色法检测HepG2细胞增殖情况,以3H-TdR参入实验检测细胞DNA合成速率,采用RT-PCR和Western blot检测PPARγmRNA和蛋白的表达,以流式细胞术检测细胞凋亡和细胞周期;同时观察PPARγ特异性拮抗剂GW9662和(或)瞬时转染pSG5-PPARγ真核表达质粒对吡格列酮细胞增殖作用的影响;并将PPARγ小干扰RNA(pGCsi-PPARγ)表达质粒稳定转染HepG2细胞,观察PPARγ沉默后吡格列酮对HepG2细胞增殖作用的影响。结果吡格列酮作用于HepG2细胞后,导致HepG2细胞的增殖受到抑制、DNA合成速率减慢,并诱导细胞凋亡,呈一定的剂量依赖关系;在此过程中,G0/G1期细胞比例明显增加,S期细胞比例明显减少,但PPARγmRNA和蛋白的表达没有变化;GW9662部分拮抗吡格列酮的增殖抑制作用,但转染pSG5-PPARγ真核表达质粒可以逆转GW9662的作用;吡格列酮在高浓度(20μmol.L-1)时对pGCsi-PPARγ表达质粒稳定转染的HepG2细胞仍表现出增殖抑制作用。结论吡格列酮能够抑制HepG2细胞的增殖并诱导凋亡,具有潜在的抗瘤作用,这种作用与其诱导细胞G0/G1期的停滞有关,PPARγ依赖和非依赖途径参与上述过程。     

Hexachlorobenzene induces TGF-β1 expression,which is a regulator of p27 and cyclin D1 modifications

Hexachlorobenzene (HCB) is an organochlorine pesticide widely distributed in the environment. In this study we have demonstrated that HCB induced loss of cell viability and alterations in cell cycle regulation in FRTL-5 rat thyroid cells. Analysis of cell cycle distribution by flow cytometric analysis demonstrated that HCB induced cell cycle arrest at G2/M and at G0/G1 phase, inhibiting cell cycle progression at the G1/S phase, after 24 h and 72 h of treatment.     

Manganese chloride-induced G0/G1 and S phase arrest in A549 cells

In the present study, we investigated the effects of manganese chloride (MnCl2) on cell cycle progression in A549 cells used as a model of Mn-induced lung toxicity. Cells were treated with various concentrations of MnCl2 (0, 0.01, 0.1, 0.5, 1.0 or 2.0 mM) for 24, 48 or 72 h. Cell proliferation was determined with MTT assay and mitotic index measurement and apoptosis was measured by flow cytometer. The results showed that MnCl2 inhibited A549 cells proliferation in a dose- and time-dependent manner, and induced apoptosis in A549 cells. When G0/G1 cells obtained by serum starvation were incubated with 0.5 mM of MnCl2 in the presence of 10% serum for several time intervals, the disruption of cell cycle progression was observed. The G0/G1 arrest was induced by MnCl2 treatment at 16 h and the arrest maintained for 8 h. Following the G0/G1 arrest, MnCl2 blocked the cells at S phase at 28 h and the S phase arrest maintained for at least 4 h. And moreover, proteasome inhibitor MG132 was able to prolong the duration of G0/G1 arrest induced by MnCl2 treatment. Results of western blotting assay revealed that cellular Cdk4, Cdk2 and phospho-Cdk2 (Thr160) levels decreased in manganese-treated cells at both 20 and 28 h. In addition, the decreasing of Cyclin A level and the increasing of p53 and WAF1/p21 were also induced by MnCl2 treatment at 20 h. The expression of Cyclin D1, Cyclin E and Cdc25A proteins was not altered in manganese-treated cells at both 20 and 28 h. Our results indicate that MnCl2 orderly induces G0/G1 and S phase arrest in A549 cells, the decreasing of Cdk4, Cdk2 and Cyclin A, and the increasing of p53 and Cdks inhibitor WAF1/p21 might be responsible for the G0/G1 arrest, and the decreasing of Cdk4 and Cdk2 levels for the S phase arrest.     

Antiproliferative activity of aucubin is through cell cycle arrest and apoptosis in human non-small cell lung cancer A549 cells

Aucubin, an iridoid glycoside isolated from the leaves of Aucuba japonica, inhibits human non-small cell lung cancer A549 cells by blocking cell cycle progression in the G(0)/G(1) phase and inducing apoptosis. An ELISA showed that the G(0)/G(1) phase arrest is due to p53-mediated induction of p21. Enhancement of Fas and its two ligands, membrane-bound and soluble Fas ligand, may be responsible for the apoptotic effect induced by aucubin. The present study shows, for the first time, that the induction of p53 and activity of the Fas/Fas ligand apoptotic system may participate in the antiproliferative activity of aucubin in A549 cells.     

Effect of berberine on proliferation,cell cycle and apoptosis in HeLa and L1210 cells

Previous studies on the anticancer activity of protoberberine alkaloids against a variety of cancer cell lines were extended to human tumour HeLa and murine leukemia L1210 cell lines. An attempt was also made to investigate the relationship between the cytotoxic activity of berberine and its molecular mechanism of action. Cytotoxicity was measured in-vitro using a primary biochemical screening according to Oyama and Eagle, and the growth inhibition assay. The in-vitro cytotoxic techniques were complemented by cell cycle analysis and determination of apoptotic DNA fragmentation in L1210 cells. Berberine acted cytotoxically on both tumour cell lines. The sensitivity of leukemia L1210 cells to the berberine was higher than that of HeLa cells. The IC(100) was below 100 microg mL(-1) for HeLa cells and approached a 10 microg mL(-1) limit for the leukemia L1210 cells. For both cell lines the IC(50) was found to be less than 4 microg mL(-1), a limit put forward by the National Cancer Institute (NCI) for classification of the compound as a potential anticancer drug. In L1210 cells treated with 10-50 microg mL(-1) berberine, G(0)/G(1) cell cycle arrest was observed. Furthermore, a concentration-dependent decrease of cells in S phase and increase in G(2)/M phase was detected. In addition, apoptosis detected as sub-G(0) cell population in cell cycle measurement was proved in 25-100 microg mL(-1) berberine-treated cells by monitoring the apoptotic DNA fragmentation (DNA ladder) using agarose gel electrophoresis.     

Ribotoxic mycotoxin deoxynivalenol induces G2/M cell cycle arrest via p21Cip/WAF1 mRNA stabilization in human epithelial cells

Deoxynivalenol (DON) and other trichothecene mycotoxins mediate a broad range of epithelial injury including atrophic growth inhibition and inflammation in the human gastrointestinal and respiratory tracts. The purpose of this study was to test the hypothesis that DON alters the cell cycle progress linked to the pathogenesis in the human epithelium. We demonstrated that human epithelial cells underwent G(2)/M phase arrest in response to DON treatment without significant increase in apoptotic cell death. Moreover, cells deficient in p21 or p53 gene expression showed the attenuated response of G(2)/M phase arrest by DON. Gene expression of p21 was also induced by DON treatment in a dose-dependent manner with no increase in p53 protein levels, suggesting p53-independent p21 induction. Signaling pathways associated with DON-induced p21 gene expression included PI3 kinase and ERK1/2 MAP kinase cascade. Particularly, ERK1/2 signal was associated with DON-induced p21 mRNA stabilization in the human epithelial cells. Taken together, deoxynivalenol arrested epithelial cell cycle at G(2)/M phase via elevated p21 gene expression.