Oleuropein Counteracts Both the Proliferation and Migration of Intra- and Extragonadal Seminoma Cells

Recent and growing literature has reported that oleuropein (OLE), the main polyphenol in olive leaf extract, inhibits tumor cell proliferation and reduces the invasiveness properties of cancer cells; therefore, OLE may play a significant role in the development of new drugs for cancer treatment. These antineoplastic properties have been reported in many experimental cancer models, but the effect of OLE on seminoma cells is yet to be evaluated. In the present study, we demonstrate, for the first time, that OLE reduces cell viability in both intra- and extragonadal TCAM-2 and SEM-1 seminoma cells, respectively, in a dose-dependent manner. As shown by Western-blot analysis, OLE exposure reduced cyclin-D1 expression and upregulated p21^Cip/WAF1, concomitantly affecting the upstream pathway of NF-κB, leading to the reduction of its nuclear content, thereby suggesting that OLE could modulate cell-cycle regulators by inhibiting NF-κB. Moreover, Annexin V staining revealed that OLE induced apoptosis in cancer cells and upregulated the pro-apoptotic factor BAX. Through wound-healing scratch and transmigration assays, we also demonstrated that OLE significantly reduced the migration and motility of TCAM-2 and SEM-1 cells, and downregulated the expression of TGFβ-1, which is known to be the main pro-fibrotic factor involved in the acquisition of the migratory and invasive properties of cancer cells. Collectively, our results indicate that OLE reduces seminoma cell proliferation, promotes apoptosis, and counteracts cell migration and motility. Further studies are needed to explore the molecular mechanisms underlying these observed effects.     

Induction of apoptosis and cell cycle arrest in cancer cells by in vivo metabolites of teas

The present study was conducted to determine in vivo possibilities of inducing apoptosis and cell cycle arrest in rat cancer cells by green, oolong, and black teas and also to further identify the mechanisms inhibiting cancer cell proliferation by the sera from tea-treated rats. The tea extracts from these three kinds of tea, the rat sera obtained after oral intubation of the tea extracts, and the tea polyphenolic compounds, (-)-epigallocatechin-3-gallate, (-)-epigallocatechin, (-)-epicatechin-3-gallate, and the aflavins, were used in the related tests. The extracts, the sera from the treated rats, and the polyphenolic compounds significantly inhibited the proliferation of a rat hepatoma cell line (AH109A) and murine B16 melanoma cells but not normal rat mesothelial (M) cells. (-)-Epicatechin exhibited synergistic effects with (-)-epigallocatechin-3-gallate, (-)-epicatechin-3-gallate, and theaflavins against AH109A cell proliferation. The fluorescence staining of the nuclei, electrophoresis detection of DNA fragmentation, and analysis of cell cycle indicated that the sera from the tea-treated rats, the tea extracts, and the related tea components resulted in loss of viability, apoptosis, and cell cycle arrest at the G1 phase in AH109A and/or B16 cells, but not in normal M cells. Our results suggest that induction of apoptosis and cell cycle arrest may be important mechanisms of in vivo proliferation inhibition of AH109A and other cancer cells by these teas.     

大蒜提取物二烯丙基三硫化物对人膀胱癌T24细胞增殖的影响

目的研究大蒜提取物二烯丙基三硫化物(DATS)于体外对人膀胱癌细胞系T24细胞增殖和细胞周期的影响及其可能机制。方法采用MTT法观察不同浓度的DATS作用不同时间后对T24细胞增殖的影响。同时应用集落形成试验观察不同浓度的DATS对T24细胞集落形成的影响。采用流式细胞仪对经不同浓度DATS作用24h后T24细胞进行细胞周期分析。应用Western blotting方法检测细胞周期相关蛋白Cdc25C的表达,以观察DATS对其的影响。结果DATS对T24细胞的增殖有明显的抑制作用,MTT法显示随药物浓度升高和作用时间延长其抑制作用逐渐增强。DATS抑制T24细胞集落形成,随着浓度增高集落形成率逐步下降。经流式细胞仪检测,不同浓度DATS作用后,G2/M期细胞逐渐增多,表明DATS可引起G2/M期停滞。不同浓度DATS作用后,Cdc25C蛋白表达随药物浓度增加。结论DATS能显著抑制T24细胞增殖和集落形成,其抑制呈时间和剂量依赖性。DATS能显著抑制T24细胞中Cdc25C蛋白的表达,这可能是诱导T24细胞G2/M期停滞的分子机制之一。     

Potential Anticancer Activity of Myricetin in Human T24 Bladder Cancer Cells Both In Vitro and In Vivo

Myricetin, a naturally occurring phytochemical, has potent anticancer-promoting activity and contributes to the chemopreventive potential of several foods. In this preliminary study, we evaluate the chemopreventive potential of myricetin against bladder cancer and its mechanism of action. The results of a MTT assay showed that myricetin was able to inhibit the viability and proliferation of T24 cells in a dose- and time-dependent manner. It also promoted cell cycle arrest at G2/M in a dose-dependent manner and induced apoptosis detected by flow cytometry and DNA fragmentation analysis. Treatment with myricetin led to G2/M cell cycle arrest in T24 cells by downregulation of Cyclin B1 and cyclin-dependent kinase cdc2. Myricetin-induced apoptosis correlates with the modulation of Bcl-2 family proteins and activation of the caspase-3. Myricetin also inhibited the phosphorylation of Akt, whereas the phosphorylation of p38 MAPK was enhanced. Myricetin had a significantly reduced T24 cell migration that was accompanied by a decreasing MMP-9 expression in vitro. Furthermore, myricetin treatment significantly inhibited the tumor growth on T24 bladder cancer xenografts model. These findings suggest that myricetin has potential anticancer activity and could be an important chemoprevention agent for bladder cancer.     

Potential anticancer activity of myricetin in human T24 bladder cancer cells both in vitro and in vivo

Myricetin, a naturally occurring phytochemical, has potent anticancer-promoting activity and contributes to the chemopreventive potential of several foods. In this preliminary study, we evaluate the chemopreventive potential of myricetin against bladder cancer and its mechanism of action. The results of a MTT assay showed that myricetin was able to inhibit the viability and proliferation of T24 cells in a dose- and time-dependent manner. It also promoted cell cycle arrest at G2/M in a dose-dependent manner and induced apoptosis detected by flow cytometry and DNA fragmentation analysis. Treatment with myricetin led to G2/M cell cycle arrest in T24 cells by downregulation of Cyclin B1 and cyclin-dependent kinase cdc2. Myricetin-induced apoptosis correlates with the modulation of Bcl-2 family proteins and activation of the caspase-3. Myricetin also inhibited the phosphorylation of Akt, whereas the phosphorylation of p38 MAPK was enhanced. Myricetin had a significantly reduced T24 cell migration that was accompanied by a decreasing MMP-9 expression in vitro. Furthermore, myricetin treatment significantly inhibited the tumor growth on T24 bladder cancer xenografts model. These findings suggest that myricetin has potential anticancer activity and could be an important chemoprevention agent for bladder cancer.     

抗菌肽merecidin通过ERK/mTOR 信号通路对肺癌A549细胞增殖、凋亡、迁移和侵袭的影响

目的 探讨抗菌肽merecidin通过ERK/mTOR 信号通路对肺癌A549细胞增殖、凋亡、迁移和侵袭的影响。方法 实验分为对照组Control、抗菌肽Merecidin干预组和雷帕霉素Rapamycin干预组。通过CCK-8 法检测A549细胞的增殖能力,通过流式细胞术检测A549细胞凋亡和周期,通过平板划痕试验和Transwell检测A549细胞的迁移和侵袭能力,通过 Western blot 法检测A549细胞中MAPK1、MEK2、mTOR、PRAS40、EIF4EBP1 磷酸化蛋白的表达量。结果 抗菌肽merecidin能够明显抑制A549的增殖能力,处理24 h后的 IC50值为10.01 μmol /L(P<0.05)。与control组比较,抗菌肽merecidin处理后促进细胞凋亡(P<0.05),阻滞细胞周期于S期(P<0.05),细胞的迁移及侵袭能力均降低(P<0.05)。同时抗菌肽merecidin可抑制p-MAPK1和p-MEK2蛋白的表达,并且降低了mTOR、PRAS40和EIF4EBP1 的磷酸化水平(P<0.05)。结论 抗菌肽merecidin可抑制肺癌A549细胞增殖、迁移和侵袭能力,促进细胞凋亡,阻滞细胞周期于S期,该作用可能与其抑制ERK/mTOR通路有关。     

The Flavonoid Quercetin Transiently Inhibits the Activity of Taxol and Nocodazole Through Interference With the Cell Cycle

Quercetin is a flavonoid with anticancer properties. In this study, we examined the effects of quercetin on cell cycle, viability, and proliferation of cancer cells, either singly or in combination with the microtubule-targeting drugs taxol and nocodazole. Although quercetin induced cell death in a dose-dependent manner, 12.5–50 μM quercetin inhibited the activity of both taxol and nocodazole to induce G2/M arrest in various cell lines. Quercetin also partially restored drug-induced loss in viability of treated cells for up to 72 h. This antagonism of microtubule-targeting drugs was accompanied by a delay in cell cycle progression and inhibition of the buildup of cyclin-B1 at the microtubule organizing center of treated cells. However, quercetin did not inhibit the microtubule targeting of taxol or nocodazole. Despite the short-term protection of cells by quercetin, colony formation and clonogenicity of HCT116 cells were still suppressed by quercetin or quercetin-taxol combination. The status of cell adherence to growth matrix was critical in determining the sensitivity of HCT116 cells to quercetin. We conclude that although long-term exposure of cancer cells to quercetin may prevent cell proliferation and survival, the interference of quercetin with cell cycle progression diminishes the efficacy of microtubule-targeting drugs to arrest cells at G2/M.     

The flavonoid quercetin transiently inhibits the activity of taxol and nocodazole through interference with the cell cycle

Quercetin is a flavonoid with anticancer properties. In this study, we examined the effects of quercetin on cell cycle, viability, and proliferation of cancer cells, either singly or in combination with the microtubule-targeting drugs taxol and nocodazole. Although quercetin induced cell death in a dose-dependent manner, 12.5-50 μM quercetin inhibited the activity of both taxol and nocodazole to induce G2/M arrest in various cell lines. Quercetin also partially restored drug-induced loss in viability of treated cells for up to 72 h. This antagonism of microtubule-targeting drugs was accompanied by a delay in cell cycle progression and inhibition of the buildup of cyclin-B1 at the microtubule organizing center of treated cells. However, quercetin did not inhibit the microtubule targeting of taxol or nocodazole. Despite the short-term protection of cells by quercetin, colony formation and clonogenicity of HCT116 cells were still suppressed by quercetin or quercetin-taxol combination. The status of cell adherence to growth matrix was critical in determining the sensitivity of HCT116 cells to quercetin. We conclude that although long-term exposure of cancer cells to quercetin may prevent cell proliferation and survival, the interference of quercetin with cell cycle progression diminishes the efficacy of microtubule-targeting drugs to arrest cells at G2/M.     

可溶性铀的内吞外排及对HK-2细胞的损伤研究

目的研究人肾近曲小管细胞(HK-2)对可溶性铀的内吞和外排情况,了解铀暴露后的细胞毒性效应。方法采用CCK-8法测定不同浓度铀染毒后细胞活性,分别在光镜和透射电子显微镜下观察细胞铀染毒后的变化;采用ICP-MS法测定细胞在不同时间对铀的内吞、外排情况;采用流式细胞仪检测铀染毒后细胞周期和细胞凋亡的变化。结果 HK-2细胞在铀暴露后出现剂量依赖性损伤,细胞周期阻滞在G1期,细胞发生凋亡和坏死,细胞增殖受到了抑制;细胞内吞的铀含量在24 h内逐渐增加,同时铀的内吞量存在阈值,细胞表面结合的铀含量分数较低(<0.2%),细胞内吞的铀1 h内40%以上都会排出胞外;铀在细胞内和细胞外均会形成针样状沉淀(300μM);结论细胞在铀染毒后出现周期阻滞、凋亡和细胞活性下降,可溶性铀的内吞、外排过程非常迅速,细胞可将可溶性铀转化为无毒性的沉淀。     

大豆苷原对体外培养人胃癌细胞增殖和细胞周期的影响

目的:了解二羟异黄酮对胃癌细胞有无促增殖与诱导凋亡作用。方法:以不同浓度的二羟异黄酮处理人胃癌细胞系MGC-803细胞。然后分别用MTT法测定细胞增殖情况、流式细胞仪和琼脂糖凝胶电泳测定细胞周期和细胞凋亡等。结果:MTT 结果显示:二羟异黄酮对胃癌细胞具有促进和抑制增殖的双相作用-在低浓度(0.1-1 μmol/L)时促进细胞生长,在较高浓度(10-100 μmol/L)时对细胞生长则有抑制作用。流式细胞术结果显示:癌细胞群阻滞在G1期,没有明显凋亡峰的出现;凝胶电泳也末检测到明显的DNA阶梯状条带。结论:二羟异黄酮对体外培养的胃癌细胞的生长有双相作用,较高浓度可抑制胃癌细胞的生长并使细胞阻滞在G1期,而无诱导细胞凋亡的作用。     

黑米皮提取物对PC-3细胞增殖的抑制作用

目的观察黑米皮提取物对人前列腺癌PC-3细胞增殖的抑制作用并探讨其机制。方法用不同浓度的黑米皮提取物(20,150和300μg/ml)处理PC-3细胞,通过MTT法、流式细胞仪、western blot法研究提取物对细胞的影响。结果处理组的细胞增殖率随着提取物作用浓度和时间的增加而降低(P<0.05);与对照组相比,处理组细胞凋亡率增加,差异有统计学意义(P<0.05);细胞周期中,G1期细胞百分比显著增多,S、G2-M期细胞显著减少,细胞被阻滞在G1-S期。与对照组相比,处理组细胞的p-p38、p-JNK的蛋白表达则随着提取物浓度的增加而增强。结论黑米皮提取物能够抑制人前列腺癌PC-3细胞的增殖,改变细胞周期的分布,激活JNK、p38通路,诱导细胞凋亡。     

溴结构域蛋白4影响胃癌恶性生物学行为的机制研究

目的探讨溴结构域蛋白4(bromodomain-containing Protein4,BRD4)影响胃癌细胞恶性生物学行为的潜在分子机制。方法在胃癌细胞HGC27和AGS中使用BRD4抑制剂JQ1,通过免疫印迹实验(western blot,WB)检测BRD4及c-MYC的蛋白水平改变,采用细胞活性测定(CCK-8)实验检测细胞增殖情况。运用shRNA构建BRD4敲减的稳定胃癌细胞HGC27和AGS,通过Western Blot验证BRD4的敲减效率,采用流式细胞术检测细胞凋亡,采用Transwell实验分析侵袭转移等恶性生物学行为。结果在胃癌细胞HGC27和AGS中,BRD4抑制剂JQ1可显著下调c-MYC的蛋白水平,且具有一定的浓度依赖性;JQ1分别与5-氟尿嘧啶(5-FU)、顺铂(cisplatin)、紫杉醇(paclitaxel)三种抗肿瘤化疗药物联合使用,明显抑制了胃癌细胞的增殖能力,且具有一定的时间、浓度依赖性。此外,敲减BRD4可促进胃癌细胞凋亡,抑制胃癌细胞的侵袭转移能力。结论BRD4在胃癌的增殖及侵袭转移等恶性进程中起到了重要的作用,有望成为胃癌临床治疗的潜在靶点。     

Plant-Derived Protease Inhibitors LC-pi (Lavatera cashmeriana) Inhibit Human Lung Cancer Cell Proliferation In Vitro

The objective of this study was to check the anticancer activity of purified protease inhibitors of Lavatera cashmeriana viz LC-pi I, II, III, and IV (Lavatera cashmeriana protease inhibitors) on A549 (lung) cell. It was found that LC-pi I and II significantly inhibited the proliferation of A549 cells with IC₅₀ value of 54 μg/ml and 38μg/ml, respectively, whereas inhibition by LC-pi III and IV was negligible. LC-pi I and II were further found to inhibit formation of colonies in a dose-dependent manner. Also, both inhibitors were found to induce apoptosis causing chromatin condensation and DNA fragmentation, without loss of mitochondrial membrane potential. Cell cycle revealed a significant increase of subG₀/G₁ phase cells that are apoptotic cells. We also demonstrated a dose-dependent decrease in migration of A549 cells on cell migration assay by both inhibitors. Taken together, we demonstrate that LC-pi I and II inhibited proliferation through arresting cells before apoptosis, inducing apoptosis and inhibiting cell migration in human lung cancer cells, but the study warrants further investigation. Our results support the notion that plant protease inhibitors may have the potential to advance as chemopreventive agents.     

Anticancer effects of the metabolic products of the resveratrol analogue, DMU-212: structural requirements for potency

The methoxylated trans-stilbene resveratrol analogue, (E)-3,4,5,4'-tetramethoxystilbene (1), has shown promising antiproliferative activity in in vitro cell line and in vivo models. In vivo 1 gives rise to several metabolic products through demethylation or hydroxylation reactions at the stilbene moiety. In the present study we examined the anticancer activity of 1 and the metabolites (E)-3'-hydroxy-3,4,5,4'-tetramethoxystilbene (2), (E)-4'-hydroxy-3,4,5-trimethoxystilbene (3), (E)-4-hydroxy-3,5,4'-trimethoxystilbene (4) and (E)-3-hydroxy-4,5,4'-trimethoxystilbene (5) by means of cell viability testing, cell cycle analysis, immunostaining and Western blotting. Compounds 1 and 2 exhibited submicromolar toxicity in MCF-7 breast adenocarcinoma and HepG2 hepatoma cells, whereas 3, 4 and 5 were inactive in terms of inhibition of cellular proliferation. Incubation with 1 or 2 at 10 μM for 24h induced apoptosis and G2/M cell cycle arrest in MCF-7 and HepG2 cells. Immunostaining of MCF-7 cells for β-tubulin in the presence of either 1 or 2 revealed shorter localization of the protein around the nucleus, as compared to control cells. Western blot analyses further demonstrated that treatment with either 1 or 2 at concentrations between 30 and 50 μM for 24 h caused a downregulation in the levels of β-tubulin and cyclin D1 expression and an upregulation in the levels of p53 expression in MCF-7 and HepG2 cells. 2 further increased the ratio of mRNA levels of the apoptosis-related genes Bax/Bcl-xL in both MCF-7 and HepG2 cells in a dose-dependent manner. We conclude that 2 inhibits HepG2 and MCF-7 cellular proliferation by inducing apoptosis and G2/M arrest through p53 and Bax/Bcl-xL upregulation. Our findings further demonstrate that trimethoxy substitutions along with the presence of a methoxy group at position 4' are necessary for retaining the activity of 1.     

辛伐他汀抑制鼻咽癌细胞增殖和亲环素A表达

目的研究辛伐他汀对鼻咽癌细胞株CNE2细胞增殖和细胞周期的作用以及对亲环素A表达的影响。方法用CCK-8方法观察辛伐他汀对鼻咽癌细胞株CNE2细胞增殖的抑制作用,用流式细胞仪检测辛伐他汀对鼻咽癌细胞株CNE2细胞周期分布的影响,用蛋白免疫印迹检测亲环素A蛋白表达。结果CCK-8方法结果显示,辛伐他汀抑制鼻咽癌细胞株CNE2细胞增殖,作用72h时IC50为2.0μmol/L。流式细胞仪结果表明辛伐他汀将鼻咽癌细胞株CNE2细胞阻滞在细胞周期的G0/G1期,蛋白免疫印迹结果显示辛伐他汀明显抑制亲环素A蛋白表达,以上效应均呈浓度依赖性。结论辛伐他汀能浓度依赖性地抑制CNE2细胞增殖,将细胞阻滞在G0/G1期,同时伴随有亲环素A表达减少。     

辛伐他汀抑制鼻咽癌细胞增殖和亲环素A表达

目的研究辛伐他汀对鼻咽癌细胞株CNE2细胞增殖和细胞周期的作用以及对亲环素A表达的影响。方法用CCK-8方法观察辛伐他汀对鼻咽癌细胞株CNE2细胞增殖的抑制作用,用流式细胞仪检测辛伐他汀对鼻咽癌细胞株CNE2细胞周期分布的影响,用蛋白免疫印迹检测亲环素A蛋白表达。结果CCK－8方法结果显示,辛伐他汀抑制鼻咽癌细胞株CNE2细胞增殖,作用72h时Ic50为2．0μmol／L。流式细胞仪结果表明辛伐他汀将鼻咽癌细胞株CNE2细胞阻滞在细胞周期的G0／G1期。蛋白免疫印迹结果显示辛伐他汀明显抑制亲环素A蛋白表达,以上效应均呈浓度依赖性。结论辛伐他汀能浓度依赖性地抑制CNE2细胞增殖．将细胞阻滞在G0／G1期。同时伴随有亲环素A表达减少。     

Pin1抑制剂对宫颈癌SiHa细胞增殖和凋亡的影响

目的:研究Pin1抑制剂(Juglone)对宫颈癌SiHa细胞增殖和凋亡的影响,探讨Juglone的抗肿瘤作用。方法:体外培养人宫颈癌细胞SiHa,采用MTT试验观察细胞生长抑制状况,流式细胞仪检测细胞周期阻滞以及Hoechst33258检测细胞凋亡情况。结果:MTT试验表明,Juglone对宫颈癌SiHa细胞生长有明显的抑制作用,且随着作用浓度和作用时间的增加,抑制作用增强。流式细胞仪检测表明,Juglone药物(50μmol/L)培养12、24、48 h后,G2/M期细胞比例数明显增加,而S期细胞比例数却较对照组降低。Hoechst33258实验组可见凋亡细胞。结论:Juglone可能通过体外抑制细胞增殖,诱导细胞凋亡途径抑制宫颈癌的发展。     

Apigenin acts on the tumor cell invasion process and regulates protease production

Apigenin is a widely distributed plant flavonoid and was proposed as an antitumor agent. In this study, we investigated the apigenin effects on the protease-mediated invasiveness in an estrogen-insensitive breast tumor cell line MDA-MB231. The results show that apigenin at 22.8-45.5 microM (2.5-10 micrograms/ml) strongly inhibited, in a dose-dependent manner, tumor cell invasion through Matrigel, cell migration, and cell proliferation. We show that apigenin treatment from 22.8 microM (2.5 micrograms/ml) led to a partial decrease in urokinase-plasminogen activator expression and to a total inhibition of phorbol 12-myristate 13-acetate-induced matrix metalloproteinase-9 secretion. We also demonstrate in the apigenin-treated cells a defective adhesion to Matrigel and a G2-M cell cycle arrest. Taken together, our results demonstrate that apigenin is a pleiotropic effector affecting protease-dependent invasiveness and associated processes and proliferation of tumor cells.     

Mechanism of growth inhibitory effect of cape aloe extract in ehrlich ascites tumor cells.

Cape aloe (Aloe ferox Miller) has been a herb well known for its cathartic properties and has also been used popularly as a health drink (juice, tea and tonic) in the United States and in Europe. Cape aloe extract also has been reported to possess several pharmacological effects, such as anti-inflammatory, anti-bacterial, anti-fungal and protective effect against liver injury. However, the investigations on an anti-tumor activity in cape aloe extract are very few and subsequent mechanisms have not been well elucidated. In this study, we examined the effect of the selective growth inhibitory activity of cape aloe extract and found that the cape aloe extract, especially the dichloromethane (CH(2)Cl(2)) extract, caused a dose-dependent growth inhibitory effect in Ehrlich ascites tumor cells (EATC), but not in mouse embryo fibroblast (NIH3T3) cells, which was used as a normal cell model. Furthermore, the CH(2)Cl(2) extract caused an accumulation of cells in the G1 phase and a decrease of cells in the S and G2/M phase of the cell cycle and inhibited DNA synthesis in a dose-dependent manner. In addition, other results suggest that cell cycle arrest and inhibition of proliferation in EATC by the CH(2)Cl(2 )extract are associated with decreased retinoblastoma protein (Rb) phosphorylation.