香豆雌酚对乳腺癌细胞株MCF-7增殖的影响

<正>乳腺癌是女性最常见的恶性肿瘤之一,它的发病与体内激素水平有关。植物雌激素是从植物中获取的结构与雌激素相似,并具有雌激素效能的天然化合物[1],它可以与雌激素受体(estrogen receptor,ER)结合,不同种类和不同浓度的植物雌激素与ER结合显示出不同的作用效能。香豆雌酚     

尿石素A对乳腺癌细胞MCF-7增殖、凋亡的影响及其机制研究

目的 研究尿石素A对乳腺癌细胞MCF-7增殖、凋亡的影响并探讨其作用机制。方法 CCK-8法考察不同浓度尿石素A作用12、24、36、48 h对MCF-7细胞增殖能力的影响;细胞凋亡染色法考察20、40 μmol/L的尿石素A对MCF-7细胞凋亡的影响;实时荧光定量PCR（RT-qPCR）检测c-Myc、Cyclin D1、Bcl-2、Bax mRNA的表达水平;Western blotting法检测c-Myc、Cyclin D1、Bcl-2、Bax蛋白的表达水平。结果 尿石素A对MCF-7细胞增殖具有抑制作用且呈时间浓度相关性;细胞凋亡染色显示,20、40 μmol/L尿石素A给药后均能够诱导MCF-7细胞凋亡;RT-qPCR及Western blotting结果显示,20、40 μmol/L尿石素A能够显著降低MCF-7细胞中c-Myc、Cyclin D1、Bcl-2 mRNA及蛋白的表达水平（P<0.05、0.01）,升高Bax mRNA及蛋白的表达水平（P<0.05、0.01）。结论 尿石素A具有抑制MCF-7细胞增殖并诱导其凋亡的作用,其作用机制可能与抑制c-Myc、Cyclin D1、Bcl-2表达,升高Bax表达水平有关。     

槲皮素、补骨脂素对乳腺癌细胞株MCF-7增殖的影响

目的探讨槲皮素(quercetin,Que)和补骨脂素(psor-alen,Pso)对人类乳腺癌细胞株增殖的影响。方法采用流式细胞术和蛋白印迹法检测槲皮素和补骨脂素对雌激素依赖性乳腺癌细胞MCF-7的影响,并以雌激素受体拮抗剂ICI182,780为工具药来评价槲皮素和补骨脂素发挥雌激素样作用与雌激素受体的关系。结果①槲皮素、补骨脂素在10μmol.L-1可使MCF-7细胞增殖指数明显升高,增加S期细胞的比例,与10-3μmon.L-1E2阳性对照组的变化趋势一致。当ICI182,780分别与E2、金雀异黄素、槲皮素、补骨脂素共孵育48 h后,E2、金雀异黄素、槲皮素、补骨脂素的增殖效应被抑制,细胞周期S期细胞数比例下降,G0/G1期细胞数比例上升。②10μmol.L-1槲皮素和10μmol.L-1补骨脂素均上调MCF-7细胞ERα蛋白水平,而对ERβ蛋白表达没有影响;当分别与ICI182,780共孵育MCF-7细胞ERα蛋白表达被拮抗。结论槲皮素和补骨脂素具有雌激素活性,此作用是通过雌激素受体(ER)介导的;产生的类似金雀异黄素促进MCF-7细胞增殖的作用是通过增加ERα表达实现的。     

铜绿假单胞茵注射液对人乳腺癌细胞的体外杀伤及促凋亡作用研究

目的研究铜绿假单胞菌（pseudo—monas aeruginosa,PA-MSHA）注射液在体外实验中对人乳腺癌细胞（MCF-7）凋亡和增殖的影响,并探讨其可能的作用机制。方法应用MTT比色法检测铜绿假单胞菌注射液对体外培养的MCF-7细胞增殖抑制作用,应用流式细胞术检测铜绿假单胞菌注射液诱导乳腺癌细胞凋亡,检测其对细胞周期的影响。用Hoechst33258染色法染色,荧光显微镜检测铜绿假单胞菌注射液诱导体外培养的MCF-7肿瘤细胞凋亡的形态学改变。结果铜绿假单胞菌注射液抑制MCK7细胞增殖,呈剂量和时间依赖性;与对照组相比,铜绿假单胞菌注射液组MCF7细胞的凋亡率明显增高（P〈0．01）、G0／G1期细胞比例明显增高、S期细胞所占百分比明显降低（P〈0．05）,染色荧光显微镜检测发现PAMSHA能诱导体外培养的肿瘤细胞呈现明显的凋亡图像。结论铜绿假单胞菌注射液可能通过对细胞周期中G0／G1期阻滞,诱导MCF-7细胞凋亡,从而抑制MCF-7细胞的增殖。     

Design,synthesis and antibreast cancer MCF-7 cells biological evaluation of heterocyclic analogs of resveratrol

A new series of resveratrol heterocyclic analogs (4a–m) were designed and synthesized, and their inhibitiory effects on MCF-7 cells were evaluated to investigate structure–activity relationship. The effects of these analogs on human breast cancer MCF-7 cells were also determined. Results showed that MCF-7 cells could be inhibited more potently by these analogs than by resveratrol (IC₅₀ = 80.0 μM). Among the analogs, compounds 4c, 4e, and 4k showed a significantly higher activity (IC₅₀ = 42.7, 48.1, and 43.4 μM) than resveratrol. Furthermore, the derivatives without additional heterocyclic structure in the 4′-OH position exhibited a more potent activity than that with addition heterocyclic structure. In addition, docking simulation was performed to adequately position compound 4c in a human F₁-ATPase active site to determine a probable binding model. These heterocyclic analogs could be effective candidates for the chemoprevention of human breast cancer.     

白藜芦醇通过激活p38-p53通路诱导人乳腺癌MCF-7细胞凋亡

本研究探讨了白藜芦醇(resveratrol,RSV)诱导人乳腺癌MCF-7细胞凋亡及其作用机制。以MTT法检测白藜芦醇对MCF-7的细胞毒性;应用Hoechst 33258染色观察细胞凋亡的形态学变化;采用流式细胞术检测细胞的凋亡率;以Western blotting检测相关蛋白的表达。结果表明,白藜芦醇可以时间和剂量依赖性地抑制MCF-7细胞的生长;60μmol.L-1白藜芦醇作用于MCF-7细胞48 h后可使细胞核皱缩、染色质凝聚,并形成明显的凋亡小体;白藜芦醇可以时间依赖性地诱导MCF-7细胞凋亡及p38和p53蛋白的活化。p38 MAPK抑制剂SB203580和p53抑制剂pifithrin-α可以显著降低白藜芦醇诱导的MCF-7细胞的生长抑制率和凋亡率;并且SB203580可以下调由白藜芦醇引起的p53的活化,而pifithrin-α对白藜芦醇引起p38的活化无影响。研究表明,白藜芦醇可以通过激活p38-p53信号通路诱导MCF-7细胞发生凋亡。     

地塞米松预处理人乳腺癌MCF-7细胞对多西他赛抗肿瘤活性的影响

目的 探讨地塞米松预处理人乳腺癌MCF-7细胞后,对化疗药物多西他赛(艾素)抗肿瘤活性的影响.方法 以不同浓度(1×10-8～1×10-6 mol·L-1)的地塞米松预先作用于人乳腺癌MCF-7细胞后,再以艾素(5×10-6 mol·L-1)处理,在以上药物作用的相应时间段,通过流式细胞仪技术测定细胞凋亡,采用细胞计数观察细胞生长密度、形态.结果 地塞米松对MCF-7细胞增殖有抑制作用(P＜0.01),艾素能够明显抑制MCF-7细胞增殖,促进其凋亡(P＜0.01),地塞米松预处理后艾素干预MCF-7细胞的增殖抑制作用较单用艾素减弱(P＜0.01),且随地塞米松浓度的增加,其对化疗药艾素的凋亡抑制作用的影响增强.结论 地塞米松预处理对艾素诱导的人乳腺癌MCF-7细胞的凋亡具有明显的阻抑作用,抑制了多西他赛的抗肿瘤活性.     

Resveratrol inhibits oral squamous cell carcinoma cells proliferation while promoting apoptosis through inhibition of CBX7 protein

As a natural compound, resveratrol (Res) is confirmed to be promising drug for the treatment of malignant tumors. Therefore, our study aimed to observe the impacts of Res on the proliferation and apoptosis of oral squamous cell carcinoma cells (HSC‐3 cells) as well as the mechanism involving chromobox protein homolog 7 (CBX7) signal transduction. HSC‐3 cells were treated with Res, Akt agonist (AL3818) and p16 inhibitor (SC79), and transfected with CBX7 mimics and inhibitor plasmids. The CCK‐8 assay was used to detect cell proliferation, flow cytometry was performed to assess cell cycle and apoptosis, and cell colonies and histone DNA level were also measured. Western blot analysis was used to determine the expression levels of related proteins. HSC‐3 cells showed decreased cell proliferation, colonies, BrdU‐counled cells and increased apoptosis, histone DNA level, the activities of caspase‐3 and caspase‐9 when treated with Res. Western blot analysis revealed elevated Cle‐PARP and Cle‐caspase 3 expression and reduced t‐PARP expression in HSC‐3 cells treated with Res compared with control. AL3818 and SC79 could decrease the inhibitory effects of Res on the growth of HSC‐3 cells. Furthermore, CBX7 overexpression could also partly reverse the roles of Res in the growth of HSC‐3 cells, and Akt and p16 signal transduction. Our results demonstrate that Res suppresses the proliferation, and induces the apoptosis of oral squamous cell carcinoma cells through the inhibition of CBX7/Akt and the activation of p16 cascades.     

Sodium arsenite alters cell cycle and MTHFR, MT1/2, and c-Myc protein levels in MCF-7 cells

There is limited available information on the effects of arsenic on enzymes participating in the folate cycle. Therefore, our aim was to evaluate the effects of sodium arsenite on the protein levels of methylenetetrahydrofolate reductase (MTHFR) and dihydrofolate reductase (DHFR) and its further relationship with the expression MT1/2 and c-myc in MCF-7 cells. Arsenite treatment (0-10 μM) for 4 h decreased MTHFR levels in a concentration-dependent fashion without significant effects on DHFR. The effects on MTHFR were observed at arsenite concentrations not significantly affecting cell viability. We also observed an increase in S-phase recruitment at all concentrations probed. Lower concentrations (< 5 μM) induced cell proliferation, showing a high proportion of BrdU-stained cells, indicating a higher DNA synthesis rate. However, higher concentrations (≥ 5 μM) or longer treatment periods induced apoptosis. Arsenite also induced dose-dependent increases in MT1/2 and c-Myc protein levels. The levels of MTHFR were inversely correlated to MT1/2 and c-Myc overexpression and increased S-phase recruitment. Our findings indicate that breast epithelial cells are responsive to arsenite and suggest that exposure may pose a risk for breast cancer. The reductions in MTHFR protein levels contribute to understand the mechanisms underlying the induction of genes influencing growth regulation, such as c-myc and MT1/2. However, further research is needed to ascertain if the effects here reported following short-time and high-dose exposure are relevant for human populations chronically exposed to low arsenic concentrations.     

金雀异黄素和槲皮素对人类乳腺癌细胞增殖和细胞周期的影响

目的探讨金雀异黄素(genistein,Gen)和槲皮素(quercetin,Que)对人类乳腺癌细胞株增殖的影响。方法采用噻唑蓝(MTT)比色法测定槲皮素对雌激素依赖性乳腺癌细胞MCF-7、T47D和非雌激素依赖性乳腺癌细胞MDA-MB231的细胞增殖作用,并以雌激素受体拮抗剂ICI182780为工具药来评价金雀异黄素、槲皮素发挥雌激素样作用与雌激素受体的关系,流式细胞术对MCF-7细胞的增殖情况进行分析。结果Gen和Que在一定剂量范围内能促进T47D和MCF-7细胞的增殖,而对雌激素受体阴性MDA-MB231细胞未见增殖作用,并将MCF-7细胞周期由G1期向S期推进,促进DNA合成,提高细胞分裂增殖指数,且Gen和Que促进MCF-7细胞增殖作用被雌激素受体拮抗剂所拮抗。结论金雀异黄素和槲皮素具有雌激素活性,此作用可能是通过雌激素受体(ER)介导的。     

4-氨基-2-三氟甲基苯基维甲酸酯对MCF-7细胞增殖和分化的影响及其机制研究

目的研究4-氨基-2-三氟甲基苯基维甲酸酯(4-ami-no-2-trifluoromethyl-phenyl retinate,ATPR)对人乳腺癌MCF-7细胞增殖和分化的作用及其可能机制。方法不同浓度的ATPR作用MCF-7细胞后,绘制细胞生长曲线,分析细胞增殖情况;瑞氏-吉姆萨染色法观察细胞形态学改变;酶联免疫法(ELISA法)检测粘蛋白(mucin 1,MUC-1)活性;RT-PCR法检测维甲酸受体(RARα、RARβ、RARγ)、维甲酸受体诱导基因1(RRIG1)、雌激素受体(ERα、ERβ)mRNA的表达;Western blot法检测RARα、RARβ、RARγ蛋白的表达。结果 ATPR明显抑制MCF-7细胞增殖,且随浓度和时间增加而逐渐增强;镜下观察ATPR作用72 h后MCF-7细胞形态趋向正常细胞分化;ELISA结果显示ATPR明显降低MCF-7细胞培养上清MUC-1浓度(P<0.05);ATPR作用MCF-7细胞72 h后,RARβ、RRIG1、ERβ表达增强(P<0.05),RARγ表达下调(P<0.05),RARα和ERα表达则无明显变化。结论 ATPR可明显抑制MCF-7细胞增殖并诱导其分化程度增高,其机制可能与调节维甲酸受体和雌激素受体平衡,并上调RRIG1表达有关。     

体外观察雷公藤内酯醇对乳腺癌细胞MCF-7增殖及凋亡的影响

目的:探讨雷公藤内酯醇(triptolide,TP)对人乳腺癌细胞MCF-7增殖及凋亡的影响。方法:MTT法检测不同条件下TP对MCF-7细胞的增殖抑制作用;倒置显微镜观察TP对MCF-7细胞形态学影响;流式细胞仪检测MCF-7细胞的凋亡情况;Caspase检测试剂盒测定Caspase-3,9的变化。结果:TP以剂量及时间依赖性方式明显抑制MCF-7细胞的增殖;TP作用MCF-7细胞后,细胞出现明显的形态学改变(形态不规则、脱落,细胞碎片等)。流式细胞仪检测5μg/mL的TP明显诱导MCF-7细胞凋亡;Caspase-3,9表达水平明显升高,和对照组相比差异有统计学意义(P<0.05)。结论:TP可能通过线粒体通路诱导MCF-7细胞凋亡而发挥其抑制作用。     

紫杉醇诱导人乳腺癌MCF-7细胞周期阻断及凋亡的基因表达谱分析

目的研究紫杉醇诱导人MCF-7细胞周期阻断及凋亡的分子机制。方法用流式细胞仪分析紫杉醇对MCF-7细胞周期变化的影响，用自制的含9 984个已知基因和EST的高密度基因芯片检测MCF-7细胞在不同浓度紫杉醇作用下的基因表达变化。结果MCF-7细胞在100 nmol·L^-1紫杉醇作用24 h，流式细胞仪结果显示77.8%细胞阻断在G₂/M期和1.3%细胞发生凋亡；基因表达谱分析发现：在12.5 nmol·L^-1 (IC₅₀)及100 nmol·L^-1紫杉醇作用下，分别有27及77个基因差异表达。结论紫杉醇可诱导MCF-7细胞周期阻断在G₂/M期并引起部分细胞凋亡，该作用与药物浓度有关。基因表达谱分析显示部分差异表达基因参与细胞微管及骨架结构、细胞周期调控、以及DNA损伤修复和凋亡过程。     

绞股蓝次级皂苷H诱导人乳腺癌MCF-7细胞凋亡的作用研究

目的 探讨绞股蓝次级皂苷H （Gypensapogenin H,GH）对人乳腺癌MCF-7细胞的诱导凋亡作用。方法 采用5、10、20、40、60、80 μmol/L的GH处理人乳腺癌MCF-7细胞48 h后,MTT法测定GH对细胞增殖的影响;20 μmol/L的GH作用细胞24 h后,相差显微镜下观察细胞的形态学变化,DAPI染色,荧光显微镜下观察凋亡小体的形成;GH作用细胞6、12、24 h后,流式细胞仪测定细胞凋亡率;免疫印迹法检测GH对Bcl-2、Bax、Cytochrome C、Caspase 3等蛋白表达的影响。结果 GH抑制细胞增殖作用呈明显的浓度相关性,半数抑制浓度（IC₅₀）为（8.67±1.22）μmol/L;GH组细胞形态与对照组比较发生显著变化,主要表现为细胞皱缩、染色质浓缩、细胞核变形;细胞经DAPI染色后在荧光显微镜下可观察到有凋亡小体形成;随GH作用时间延长,细胞凋亡率明显上升,与对照组比较,GH作用12、24 h细胞早期凋亡率显著升高（P<0.05、0.01）;蛋白免疫印迹显示,与对照组比较,GH作用6、24 h Bax,6、12、24 h Cleaved Caspase 3和Cytochrome C蛋白水平显著增加（P<0.05、0.01）;6、12、24 h Bcl-2和12、24 h Caspase 3蛋白表达量显著减少（P<0.05、0.01）。结论 GH通过线粒体通路诱导乳腺癌MCF-7细胞凋亡。     

18F-氟代脱氧葡萄糖诱导MCF-7细胞株的凋亡研究

目的研究18F-氟代脱氧葡萄糖(18F-FDG)诱导体外培养MCF-7乳腺癌细胞的凋亡情况。方法不同剂量18F-FDG加入体外培养MCF-7乳腺癌细胞中共培养,以γ计数仪测定细胞摄取18F-FDG的量;用流式细胞仪测定细胞早期和晚期凋亡率;用TUNEL法测定细胞凋亡的数量。结果①相同数量级的MCF-7细胞对18F-FDG的摄取量与剂量增加呈线性;②流式细胞结果示:经12 h18F-FDG孵育引起MCF-7的平均早期凋亡率为12.5%,平均晚期凋亡率为39.3%,总平均凋亡率为51.8%。经24 h18F-FDG孵育引起MCF-7的平均早期凋亡率为10.4%,平均晚期凋亡率为42.1%,总平均凋亡率为52.5%;③TUNEL显示:用凋亡指数(apoptotic index,AI)表示,与空白对照组AI(5.13±1.51)%相比,18F-FDG孵育12 h爬片的AI为(45.93±1.51)%,18F-FDG孵育24 h爬片的AI为(46.93±1.52)%。结论一定剂量范围内,18F-FDG对MCF-7细胞诱导凋亡效果显著。     

蛇床子素通过p53信号通路诱导人乳腺癌细胞株MCF-7凋亡

目的 探讨蛇床子素对人乳腺癌细胞株MCF-7的作用及其机制。方法 对数生长期的MCF-7 细胞用0,25,50,100 mmol·L^-1的蛇床子素处理。细胞培养48 h后,利用MTT检测细胞增殖;流式检测细胞凋亡和膜电位。RT-PCR检测p53、p21、BCL-2、Bax和CytC mRNA水平;免疫印迹法检测p53、p21、BCL-2、Bax 和CytC 表达。结果 蛇床子素可以成浓度依赖性诱导MCF-7 细胞增殖抑制和凋亡,上调Bax、p53、p21和CytC表达,下调 Bcl-2的表达以及细胞膜电位。结论 蛇床子素可通过激活p53信号通路而诱导MCF-7细胞凋亡。     

三氧化二砷诱导乳腺癌细胞株MCF-7凋亡对端粒酶活性的影响

<正>乳腺癌是严重威胁妇女健康的恶性肿瘤之一,近年发病率逐年上升,且发病年龄也趋于年轻化。近年来研究发现As2O3不仅对APL细胞,而且对其他血液肿瘤细胞和许多实体瘤细胞均具有诱导凋亡作用。Wang等研究表明端粒酶与恶性肿瘤发生有着紧密的关联,p21特异性核苷     

P53-mediated cell cycle arrest and apoptosis through a caspase-3- independent, but caspase-9-dependent pathway in oridonin-treated MCF-7 human breast cancer cells

Aim： To study the caspase-3-independent mechanisms in oridonin-induced MCF-7 human breast cancer cell apoptosis in vitro. Methods： The viability of oridonin- treated MCF-7 cells was measured by MTT （thiazole blue） assay. Apoptotic cells with condensed nuclei were visualized by phase contrast microscopy. Nucleosomal DNA fragmentation was assayed by agarose gel electrophoresis. The apoptotic ratio was determined by lactate dehydrogenase assay. Cell cycle alternation and mitochondrial membrane potential were measured by flow cytometric analysis. Bax, Bcl-2, caspase-3, caspase-9, heat shock protein （Hsp）90, p53, p-p53, p21, Poly （ADP-ribose） polymerase （PARP）, and the inhibitor of caspase-activated DNase （ICAD） protein expressions were detected by Western blot analysis. Results： Oridonin inhibited cell growth in a time- and dose-dependent manner. Cell cycle was altered through the upregulation of p53 and p21 protein expressions. Pancaspase inhibitor Z-VAD-fmk and calpain inhibitor II both decreased cell death ratio. Nucleosomal DNA fragmentation and the downregulation of △ψmit were detected in oridonin-induced MCF-7 cell apoptosis, which was involved in a postmitochondrial caspase-9-dependent pathway. Decreased Bcl-2 and Hsp90 expression levels and increased Bax and p21 expression levels were positively correlated with elevated levels of phosphorylated p53 phosphorylation. Moreover, PARP was partially cleaved by calpain rather than by capase-3. Condusion： DNA damage provoked alternations in the mitochondrial and caspase-9 pathways as well as p53-mediated cell cycle arrest, but was not related to caspase-3 activity in oridonin-induced MCF-7 cells.     

Growth inhibition and induction of apoptosis in MCF-7 breast cancer cells by oridonin nanosuspension

The mechanism for anti-tumor activity of oridonin (ORI) nanosuspension, prepared by the high pressure homogenization method, was studied using MCF-7 human breast carcinoma cells in vitro. MTT assay, observation of morphologic changes, flow cytometric analysis, and western blot analysis indicated that ORI nanosuspension could significantly intensify the in vitro anti-tumor activity to MCF-7 cells, as compared with ORI solution. Furthermore, ORI nanosuspension induced G₂/M stage proliferation arrest and apoptosis in MCF-7 cells depending on its concentration. In addition, western blot analysis indicated that the pro-caspase-3 protein was not cleaved into the activated form and the expression of anti-apoptotic Bcl-2 protein decreased, on the contrary, the expression of pro-apoptotic Bax protein increased in a dose-dependent manner in ORI nanosuspension-treated cells. These observations indicated that the anti-tumor activity of ORI nanosuspension was intensified by cell-cycle arrest and apoptosis induction.     

Silencing livin gene by siRNA leads to apoptosis induction, cell cycle arrest, and proliferation inhibition in malignant melanoma LiBr cells

Aim： The aim of the present study was to investigate the effects of silencing the livin gene by small interfering RNA （siRNA） on the expression of livin and the effects on apoptosis, cell cycle, and proliferation in human malignant melanoma LiBr cells. Methods： Three chemically-synthetic siRNA duplexes targeting livin were transiently transfected into the LiBr cells, and the effects on livin expression were detected both at the mRNA level by real-time RT-PCR and at the protein level by Western blotting. Apoptosis was evaluated by terminal deoxynucleotidyl transferase-mediated digoxigenin-dUTP nick-end labeling assay, flow cytometric analysis, and the expression of procaspase-3 and activated caspase-3 analysis by Western blotting. Cell cycle was analyzed by flow cytometry. Cell proliferation was determined by 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide. Results： One of the 3 designed siRNA could effectively knock down the livin expression both at the mRNA and protein levels in dose- and time-dependent manners; 100 nmol/L with maximum downregulation on mRNA at 48 h, and on the protein at 72 h after transfection. Silencing livin could significantly induce apoptosis, arrest cell cycle at the Go/G1 phase, and inhibit proliferation in LiBr cells. Meanwhile, caspase-3 was activated. Conclusion： The livin gene could serve as a potential molecular target for gene therapy by siRNA for malignant melanoma.