下调CENP-E对乳腺癌MCF-7细胞的影响

目的:探讨有丝分裂检查点蛋白着丝粒蛋白-E(CENP-E)基因在肿瘤发生发展中的作用。方法:利用shRNA下调CENP-E基因的表达,分别用巢式PCR和Western blot检测CENP-E mRNA和蛋白的表达;MTT检测CENP-E下调后MCF-7细胞的增殖变化;流式细胞术检测CENP-E下调后对MCF-7细胞凋亡的影响;Transwell试验检测MCF-7细胞的迁移和侵袭能力变化;间接免疫荧光检测细胞内CENP-E蛋白和有丝分裂情况。结果:shRNA能有效抑制CENP-E mRNA和蛋白的表达。MTT结果显示CENP-E下调后MCF-7细胞的增殖能力减弱(P<0.05);流式细胞术显示下调CENP-E后能促进MCF-7细胞的凋亡;间接荧光结果显示CENP-E干扰后MCF-7细胞内CENP-E蛋白减少并伴有核分裂异常;Transwell试验显示CENP-E干扰组细胞的迁移和侵袭能力增强(P<0.05)。结论:下调部分CENP-E的表达能抑制MCF-7细胞的增殖,促进MCF-7细胞的凋亡,增强MCF-7细胞的迁移和侵袭能力。     

胰岛素样生长因子-1 受体(IGF-IR)在乳腺癌组织中的表达及其 临床意义初探

目的:检测分析胰岛素样生长因子-1受体(IGF-IR)在乳腺癌组织中的表达状况及其临床意义。方法:应用半运用半定量RT-PCR方法分析84例乳腺癌和癌旁正常乳腺组织中IGF-1R基因mRNA的表达水平,并分析其表达与患者临床病理特征及预后之间的关系。结果:乳腺癌组织中IGF-1R基因mRNA表达水平显著高于癌旁乳腺组织,二者具有统计学差别(P<0.001)。乳腺癌组织中IGF-1R基因mRNA表达水平与肿瘤组织分化程度及乳腺癌患者的TNM分期和淋巴结转移情况显著相关(P值分别是0.005,0.025和0.041)。另外,高表达IGF-1R的乳腺癌患者的五年总体生存率(38.3%)显著高于低表达IGF-1R的患者(49.7%;P=0.009)。多因素COX模型分析结果表明:IGF-1R基因mRNA表达水平是乳腺癌患者的一个独立预后分子(HR=2.78,95%CI:1.94-3.94,P=0.041)。结论:IGF-1R基因表达水平上调在乳腺癌发展过程中起着重要的作用。IGF-1R基因mRNA表达水平有望成为临床乳腺癌患者预后判断的一个重要分子标志物。     

胰岛素样生长因子-1受体（IGF—IR）在乳腺癌组织中的表达及其临床意义初探

目的：检测分析胰岛素样生长因子-1受体（IGF-IR）在乳腺癌组织中的表达状况及其临床意义。方法：应用半运用半定量RT-PCR方法分析84例乳腺癌和癌旁正常乳腺组织中IGF—IR基因mRNA的表达水平,并分析其表达与患者临床病理特征及预后之间的关系。结果：乳腺癌组织中IGF-IR基因mRNA表达水平显著高于癌旁乳腺组织,二者具有统计学差别（P〈0．001）。乳腺癌组织中IGF-IR基因mRNA表达水平与肿瘤组织分化程度及乳腺癌患者的TNM分期和淋巴结转移情况显著相关（P值分别是0．005,0．025和0．041）。另外,高表达IGF-IR的乳腺癌患者的五年总体生存率（38．3％）显著高于低表达IGF-1R的患者（49．7％;P=0．009）。多因素COX模型分析结果表明：IGF-IR基因mRNA表达水平是乳腺癌患者的一个独立预后分子（HR=2．78,95％CI：1．94-3．94,P=0．041）。结论：IGF-IR基因表达水平上调在乳腺癌发展过程中起着重要的作用。IGF-IR基因mRNA表达水平有望成为临床乳腺癌患者预后判断的一个重要分子标志物。     

磺化壳聚糖对MCF-7的体外抑制作用研究

目的:研究磺化壳聚糖(SCTS)对体外培养的人乳腺癌细胞的增殖抑制和凋亡的作用.方法:用不同浓度磺化壳聚糖对体外培养人乳腺癌细胞MCF-7进行干预,MTT法检测SCTS对MCF-7细胞增殖的抑制作用;显微荧光法、流式细胞术检测细胞凋亡.结果:磺化壳聚糖抑制MCF-7细胞增殖,且呈时间、剂量依赖性;镜下可见凋亡细胞的形态学改变、FCM显示G0/G1期细胞增加,而S期细胞减少.结论:磺化壳聚糖可有效抑制人乳腺癌细胞MCF-7增殖,促进细胞凋亡.     

siRNA对乳腺癌细胞Cyclin E表达和生长抑制作用

研究siRNA对乳腺癌MCF-7细胞株cyclin E表达的抑制及对细胞生长的影响。化学合成针对cyclin E基因的小干扰RNA（siRNA）,转染MCF-7细胞株;分别应用荧光定量PCR和免疫印迹测定cyclin E mRNA和蛋白质的表达,CCK-8测定细胞的增殖活性,流式细胞仪检测细胞周期,软琼脂培养检测细胞克隆形成能力。10、50、100nmol／L siRNA-cyclin E分别使MCF-7细胞cyclin E基因表达降低了24．7％、62．5％和71．0％,蛋白质表达降低了40．8％、66．5％和71．3％。转染siRNA-cyclin E后,G1期细胞增多,S期减少,增殖受到抑制,软琼脂克隆形成率降低。结果提示,在MCF-7细胞株中,导入针对cyclin E的siRNA,可有效抑制cyclin E的表达,进而使细胞增殖减缓,逆转其恶性表型。     

谷氨酸对大鼠脂肪干细胞诱导分化神经细胞的影响及机制

目的:研究谷氨酸(Glu)对大鼠脂肪干细胞Adipose-derived stem cells(ADCSs)诱导分化神经细胞的作用及机制。方法:取成年大鼠腹股沟脂肪组织进行体外细胞培养,采用免疫组化方法检测证实为ADSCs。对照组为正常培养的ADSCs并诱导分化神经细胞,谷氨酸(Glu)处理组加入不同浓度的Glu,MTT比色法观察脂肪干细胞的存活率。结果:从ADSCs诱导分化的细胞包括神经元及神经胶质细胞,免疫组化结果显示神经元特异性烯醇化酶(NSE)染色阳性和胶质纤维酸性蛋白(GFAP)染色阳性。Glu处理组给药24h后,与对照组比较ADSCs存活率明显降低,50μmol·L-1Glu组细胞存活率为83.98%,与对照组比较差异无显著性(P>0.05);100及1000μmol·L-1Glu组干细胞存活率(分别为66.82%和17.08%)低于对照组(P<0.05,P<0.01)。结论:Glu对ADSCs有损伤作用,随着Glu剂量的增加,ADSCs的存活率逐渐降低,二者呈剂量依赖关系。     

色胺酮对乳腺癌MCF-7细胞凋亡的诱导作用

目的:探讨色胺酮(Tryptanthrin,Try)对人乳腺癌MCF-7细胞增殖和凋亡的影响。方法:利用MTT方法检测Try(1.56-100μmol/L)对细胞增殖的影响;透射电镜观察细胞的形态学改变;流式细胞术检测细胞周期、凋亡情况及线粒体跨膜电位等指标。结果:MTT结果显示,Try在12.5-100μmol/L浓度范围内能明显抑制MCF-7细胞的增殖,并具有时间和浓度依赖性;透射电镜下可见Try作用48h后,MCF-7细胞有典型的凋亡样改变。Annexin V-FITC与PI双染,流式细胞仪检测结果显示:50、100μmol/LTry作用后,细胞的凋亡情况明显,与对照组相比差异显著;且影响了MCF-7的细胞周期分布,将细胞阻滞于G1期,抑制其DNA的合成;并导致细胞线粒体跨膜电位下降。结论:色胺酮能明显抑制MCF-7细胞增殖并具有诱导细胞发生凋亡的作用。     

Doxorubicin Impairs the Insulin-Like Growth Factor-1 System and Causes Insulin-Like Growth Factor-1 Resistance in Cardiomyocytes

BackgroundInsulin-like growth factor-1 (IGF-1) promotes the survival of cardiomyocytes by activating type 1 IGF receptor (IGF-1R). Within the myocardium, IGF-1 action is modulated by IGF binding protein-3 (IGFBP-3), which sequesters IGF-1 away from IGF-1R. Since cardiomyocyte apoptosis is implicated in anthracycline cardiotoxicity, we investigated the effects of the anthracycline, doxorubicin, on the IGF-1 system in H9c2 cardiomyocytes.ConclusionsDoxorubicin down-regulates IGF-1R and up-regulates IGFBP-3 via p53 and oxidative stress in H9c2 cells. This leads to resistance to IGF-1 that may contribute to doxorubicin-initiated apoptosis. Further studies are needed to confirm these findings in human cardiomyocytes and explore the possibility of manipulating the IGF-1 axis to protect against anthracycline cardiotoxicity.     

A Mathematical Model of Cell Cycle Progression Applied to the MCF-7 Breast Cancer Cell Line

In this paper, we present a model of cell cycle progression and apply it to cells of the MCF-7 breast cancer cell line. We consider cells existing in the three typical cell cycle phases determined using flow cytometry: the G1, S, and G2/M phases. We further break each phase up into model phases in order to capture certain features such as cells remaining in phases for a minimum amount of time. The model is also able to capture the environmentally responsive part of the G1 phase, allowing for quantification of the number of environmentally responsive cells at each point in time. The model parameters are carefully chosen using data from various sources in the biological literature. The model is then validated against a variety of experiments, and the excellent fit with experimental results allows for insight into the mechanisms that influence observed biological phenomena. In particular, the model is used to question the common assumption that a ‘slow cycling population’ is necessary to explain some results. Finally, an extension is proposed, where cell death is included in order to accurately model the effects of tamoxifen, a common first line anticancer drug in breast cancer patients. We conclude that the model has strong potential to be used as an aid in future experiments to gain further insight into cell cycle progression and cell death.     

软骨多糖对MCF-7乳腺癌细胞VEGF和bFGF的表达影响

目的:研究软骨多糖对乳腺癌血管生成抑制作用的机制.方法:选用MCF-7人乳腺癌细胞系体外培养,应用MTT法检测细胞生长抑制率;HE染色法观察细胞形态学变化;免疫荧光检测VEGF、bFGF蛋白表达.软骨多糖浓度为200 μg.ml-1.结果:MTT实验结果表明软骨多糖能够显著抑制人乳腺癌细胞MCF-7的生长,且呈现一定的浓度依赖性和时间依赖性.HE染色观察结果表明乳腺癌细胞MCF-7经软骨多糖作用后,细胞开始出现凋亡现象,如产生空泡、胞膜扩散、胞质外溢、形态变圆、胞核皱缩等,最终导致大量细胞破碎死亡.免疫荧光实验结果表明软骨多糖对乳腺癌细胞MCF-7的VEGF和bFGF两种血管生长因子的合成与分泌有显著的抑制作用,且抑制呈浓度与时间依赖性.结论:软骨多糖对乳腺癌细胞MCF-7有直接杀伤作用,并可能通过抑制乳腺癌细胞VEGF和bFGF的合成分泌而抑制乳腺癌的血管生成.     

A Model for Transfer of P-Glycoproteins in MCF-7 Breast Cancer Cell Line with Multiple Transfer Rules

In this paper, we consider a direct protein transfer process between cells in co-culture. Assuming that cells continually encounter each other, and from some hypotheses on cell-to-cell rules of transfer, we derive discrete and continuous Boltzmann-like integro-differential equations. The novelty of this model is to take into account multiple transfer rules. This new transfer model is used to fit the experimental data of cell-to-cell protein transfer in breast cancer.     

Impact of miRNA Sequence on miRNA Expression and Correlation between miRNA Expression and Cell Cycle Regulation in Breast Cancer Cells

The miRNAs regulate cell functions by inhibiting expression of proteins. Research on miRNAs had usually focused on identifying targets by base pairing between miRNAs and their targets. Instead of identifying targets, this paper proposed an innovative approach, namely impact significance analysis, to study the correlation between mature sequence, expression across patient samples or time and global function on cell cycle signaling of miRNAs. With three distinct types of data: The Cancer Genome Atlas miRNA expression data for 354 human breast cancer specimens, microarray of 266 miRNAs in mouse Embryonic Stem cells (ESCs), and Reverse Phase Protein Array (RPPA) transfected by 776 miRNAs in MDA-MB-231 cell line, we linked the expression and function of miRNAs by their mature sequence and discovered systematically that the similarity of miRNA expression enhances the similarity of miRNA function, which indicates the miRNA expression can be used as a supplementary factor to predict miRNA function. The results also show that both seed region and 3'' portion are associated with miRNA expression levels across human breast cancer specimens and in ESCs; miRNAs with similar seed tend to have similar 3'' portion. And we discussed that the impact of 3'' portion, including nucleotides , is not significant for miRNA function. These results provide novel insights to understand the correlation between miRNA sequence, expression and function. They can be applied to improve the prediction algorithm and the impact significance analysis can also be implemented to similar analysis for other small RNAs such as siRNAs.     

蛋白酪氨酸磷酸酶SHP-2在乳腺癌细胞移动及粘附中的作用

探讨蛋白酪氨酸磷酸酶SHP 2在乳腺癌细胞MCF 7的移动及粘附中的作用 .利用基因重组技术分别将野生型SHP 2与突变型SHP 2与绿色荧光蛋白GFP的基因片段构成重组质粒 (SHP 2 GFP、SHP 2C >S GFP) .脂质体转染法分别转入MCF 7中 ,表达成功后筛选并建立SHP 2 GFP和SHP 2C >S GFP细胞株 .荧光显微镜观察细胞移动情况 ,免疫印迹法检测粘附分子E 钙粘蛋白和金属蛋白酶MMP 1及MMP 9的表达 .实验后建立SHP 2 GFP及SHP 2C >S GFP细胞株 ,同时观察到SHP 2C >S GFP细胞的形态发生明显改变 :从梭形状态变成圆形状态 .荧光显微镜发现 ,MCF 7细胞和SHP 2 GFP、SHP 2C >S GFP转染的细胞在 3h、6h、9h的移动情况分别是MCF 7为 10 %、2 3%、5 4% ,SHP 2 GFP为 15 %、4 9%、98% ,SHP 2C >S GFP为 4 %、11%、30 % .免疫印迹结果表明 ,SHP 2C >S GFP细胞的E 钙粘蛋白表达比SHP 2 GFP细胞明显升高 (P <0 0 5 ) .MMP 1及MMP 9的表达量在SHP 2 GFP细胞中有所增强 (P <0 0 5 ) .实验表明 ,SHP 2可能通过调节粘附分子和基质金属磷酸酶而在细胞移动、粘附中发挥重要作用     

LRP16对乳腺癌MCF-7细胞增殖的影响

用Northern印迹方法检测雌二醇 (17β E2 )对LRP16mRNA表达的时间及剂量依赖性调控作用 .构建LRP16基因启动子序列调控的萤光素酶报告子 (pS0 ) ,并与雌激素受体α和 β(ERα和ERβ)表达载体共转染COS 7和MCF 7细胞后测定萤光素酶活性 .将LRP16基因的表达载体转染MCF 7细胞 ,测定过表达LRP16对细胞的生长特性的影响 .17β E2 使MCF 7细胞中LRP16mRNA表达水平增加 ,增加幅度未显示出 17β E2 培养时间和剂量的依赖性 .pS0 与ERα表达载体共转染细胞的相对萤光素酶活性较非共转染组 (对照组 )及pS0 ERβ表载体共转染组升高 5～ 10倍 .LRP16基因过表达促进MCF 7细胞的增殖 .研究表明 ,雌激素可能通过ERα上调乳腺癌MCF 7细胞LRP16基因的表达并促进细胞增殖     

Breast Cancer Metastasis Suppressor 1 Regulates Hepatocellular Carcinoma Cell Apoptosis via Suppressing Osteopontin Expression

Breast cancer metastasis suppressor 1 (BRMS1) was originally identified as an active metastasis suppressor in human breast cancer. Loss of BRMS1 expression correlates with tumor progression, and BRMS1 suppresses several steps required for tumor metastasis. However, the role of BRMS1 in hepatocellular carcinoma (HCC) remains elusive. In this study, we found that the expression level of BRMS1 was significantly down-regulated in HCC tissues. Expression of BRMS1 in SK-Hep1 cells did not affect cell growth under normal culture conditions, but sensitized cells to apoptosis induced by serum deprivation or anoikis. Consistently, knockdown of endogenous BRMS1 expression in Hep3B cells suppressed cell apoptosis. We identified that BRMS1 suppresses osteopontin (OPN) expression in HCC cells and that there is a negative correlation between BRMS1 and OPN mRNA expression in HCC tissues. Moreover, knockdown of endogenous OPN expression reversed the anti-apoptosis effect achieved by knockdown of BRMS1. Taken together, our results show that BRMS1 sensitizes HCC cells to apoptosis through suppressing OPN expression, suggesting a potential role of BRMS1 in regulating HCC apoptosis and metastasis.     

Insulin-Like Growth Factors,Insulin, and Growth Hormone Signaling in Breast Cancer: Implications for Targeted Therapy

ObjectiveIn recent decades, multiple therapeutics targeting the estrogen and human epidermal growth factor-2 (HER2) receptors have been approved for the treatment of breast cancer.MethodsThis review discusses a number of growth factor pathways that have been implicated in resistance to both anti-estrogen and HER2-targeted therapies. The association between growth factors and breast cancer is well established. Over decades, numerous laboratories have studied the link between insulin-like growth factor (IGF), insulin, and growth hormone (GH) to the development and progression of breast cancer.ResultsAlthough preclinical data demonstrates that blockade of these receptors inhibits breast cancer growth, progression, and drug resistance, therapies targeting the IGF, insulin, and GH receptors (GHRs) have not been successful in producing significant increases in progression- free, disease-free, or overall survival for patients with breast cancer. The failure to demonstrate a benefit of growth factor blockade in clinical trials can be attributed to redundancy in IGF, insulin, and GHR signaling pathways. All 3 receptors are able to activate oncogenic phosphoinositide- 3 kinase (PI3K) and mitogen-activated protein kinase (MAPK) pathways.ConclusionConsequently, multitargeted blockade of growth factor receptors and their common downstream kinases will be necessary for the successful treatment of breast cancer. (Endocr Pract. 2014;20:1214-1221)     

Regulation of Sialyltransferase Expression by Estradiol and 4-OH-Tamoxifen in the Human Breast Cancer Cell MCF-7

We have addressed the effects of estradiol and 4-OH-tamoxifen on the expression of five sialyltransferases in the hormono-dependent MCF-7 cell line using a Multiplex RT-PCR approach. Estradiol induced a statistically significant increase in ST3Gal III and a decrease in ST6Gal I, whereas the two other enzymes, ST3Gal IV and ST3Gal I, are not modified and expression of the fifth enzyme, ST3Gal II, was very low or not detectable. Estradiol effects were dose dependent and completely antagonized by 4OH-tamoxifen. In addition, there is no direct relation between cellular proliferation and sialyltransferase expression. This suggests that ST3Gal III and ST6Gal I could be used as supplementary markers of hormono-sensitivity in breast cancer.     

An ATP-Sensitive K+ Current that Regulates Progression Through Early G1 Phase of the Cell Cycle in MCF-7 Human Breast Cancer Cells

Whole-cell recordings were used to identify in MCF-7 human breast cancer cells the ion current(s) required for progression through G1 phase of the cell cycle. Macroscopic current-voltage curves were fitted by the sum of three currents, including linear hyperpolarized, linear depolarized and outwardly rectifying currents. Both linear currents, but not the outwardly rectifying current, were increased by 1 μm intracellular Ca²⁺ and blocked by 2 mm intracellular ATP. When tested at concentrations previously shown to inhibit proliferation by 50%, linogliride, glibenclamide and quinidine inhibited the linear hyperpolarized current, and quinidine and linogliride inhibited the linear depolarized current; none of these agents affected the outwardly rectifying current. In contrast, tetraethylammonium completely inhibited the outwardly rectifying current, but did not inhibit either linear current. Changing the bath solution to symmetric K⁺ shifted the reversal potential of the linear hyperpolarized current from near the K⁺ equilibrium potential (−84 mV) to −4 mV. Arrest of the cell cycle in early G1 by quinidine was associated with significantly smaller linear hyperpolarized currents, without a change in the linear depolarized or outwardly rectifying currents, but this reduction was not observed with arrest by lovastatin at a site ≈6 hr later in G1. The linear hyperpolarized current was significantly larger in ras-transformed than in untransformed cells. We conclude that the linear hyperpolarized current is an ATP-sensitive K⁺ current required for progression of MCF-7 cells through G1 phase. Received: 22 January 1999/Revised: 11 May 1999