Triterpenoid of avocado (Persea americana) seed and its cytotoxic activity toward breast MCF-7 and liver HepG2 cancer cells

Objective:To determine the structure of triterpenoid isolated from avocado seeds and the cytotoxic effect on MCF-7 and Hep G2 cells.Methods:The powder sample was macerated with ethanol,followed with separation of the extract by column chromatography.The target compound was monitored on thin layer chromatography plate and reagent Lieberman–Buchard.The isolated compound was characterized by spectral analysis,mainly ultraviolet,infrared,and liquid chromatographymass spectroscopy and their spectroscopic data with those reported in literature were compared.In vitro cytotoxic activity was investigated against Vero,MCF-7,and Hep G2 cell lines using MTT assay.Results:A triterpenoid compound was isolated from ethanol extract.The extracts,fraction(F3),and the isolated compound showed a significant cytotoxic activity against all investigated cell lines.MTT assay showed that the triterpenoid isolate inhibited cell proliferation of MCF-7 and Hep G2 cell line with the IC50 values of 62 mg/m L and 12 mg/m L,respectively,and was safe to normal cells.Conclusions:The results of the present study reveal that triterpenoid from avocado seeds have the potential for further development as anticancer agents.

A Variant of Human Estrogen Receptor-α,hER-α36 Weakens Docetaxel Drug Efficacy against Human Breast Cancer Cell Line MCF-7

Objective： hER-α36 is a variant of estrogen receptor-a, identified and cloned by a team of American. This research is to determine whether hER-α36 can enhance or weaken chemosensitivity to docetaxel in breast cancer cell line MCF-7（ERα66 positive）. Methods： RT-PCR was used to detect the expressions of ERα66 and ERa36 in the two human breast cancer cell lines MCF-7（MCF-7/ERα66） and MCF-7 transfected with ERa36（MCF-7/ERα36）. The two cell lines were treated with docetaxel（0-100umol/L）, and cell growth and apoptosis were evaluated using MTT （3-（4,5-dimethylthiazol- 2-yl）-2,5-diphenyl tetrazolium bromide） assay （using adriamycin （0-50umol/L） as the control） and flowcytometry. Western blot analysis was used to measure the effect of docetaxel on phosphor-ERKl/2 expression in the two cell lines. Results： The expressions of ERct36 and ERα66 were detectable in both MCF-7/ERα66 and MCF-7/ERα36 cell lines, while the expression of ERα36 in MCF-7/ER36 cells was higher. Both docetaxel and adriamycin inhibited the proliferation of both cells lines in a dose and time dependent manner. In comparison with MCF-7/ERα36 cell line, the MCF-7/ERα66 cells produced greater growth inhibition and apoptosis after treatment with docetaxel, but there was no significant difference in growth inhibition between the two cell lines treated with adriamycin; The MCF-7/ERα36 cell line resulted in a significant activation （phosphorylation） of ERK1/2 after treatment with docetaxel in a dose-dependent manner, but in the MCF-7/ERα66 cell line , a decrease in the level of phosphor- ERK1/2 expression was observed as the dose of docetaxel increased. Conclusion： ERa36 may be an agent that weakens chemosensitivity to docetaxel in breast cancer, probably by activating the expression of ERKI/2.

Dietary Daidzein Enhances Antiapoptotic Effect of 17β-Estradiol (E_2) on Breast Cancer MCF-7 Cells

Objective： To investigate whether dietary daidzein interact with endogenous 17β-Estradiol （E2） to give rise to additive or inhibitory effects on proliferation and apoptosis in breast cancer cells. Methods： Cell cycle distribution and apoptosis induction were analyzed by using flow cytometry when breast cancer cell lines MCF-7 were cotreated with daidzein （1, 5 μmol/L） and E2 （0.1-10 nmol/L） for 5 days. Whether daidzein could alter E2-modulated mRNA expression of estrogen receptor alpha （ERα）, estrogen receptor beta （ERI3） and ERβ-estrogen response element （ERE） dependent transcription was investigated by RT-PCR and luciferase induction assays. The effects of daidzein on E2-modulated expression of proapoptotic p53, bax and antiapoptotic bcl-2 at both mRNA and protein levels were also investigated by RT-PCR and Western blot. Results： Daidzein enhanced the antiapoptotic effect in an Ea dose-dependent manner, but had no effect on E2-induced proliferation. Daidzein antagonized E2-induced ERβ mRNA expression and ERβ-ERE dependent transcription. In addition, daidzein only antagonized E2-upregulated expression of p53 and bax, but had no effect on E2-upregulated expression of bcl-2. Conclusion： Daidzein enhances the antiapoptotic effect of E2 on breast cancer cells by inhibiting E2-mediated p53-bax proapoptotic pathway. These results suggest that dietary daidzein may enhance deleterious effect of endogenous E2 in hormone-dependent breast cancer.

Studies on mechanism of cis9,trans11-CLA and trans10,cis12-CLA inducing apoptosis of human breast cancer cell line MCF-7

Objective： The aim of the study was to explore the activities of cis9, trans11-CLA （C9, t11-CLA） and transl0, cis12-CLA （t10, c12-CLA） inhibiting tumor, and investigate their relationships with PPARy and apoptotic proteins, and mechanism of anti-cancer. Methods： The inhibitory rate, cell growth curve and apoptotic morphological observation of MCF-7 cells were obtained by MTT assay, trypan blue staining and Hoechst33342 fluorescence staining. The apoptotic rate and cell cycle were detected with flow cytometry. Transcriptional level of genes was detected with RT-PCR semi-quantitative method, and Western blot was performed to detect proteins levels. Results： The two CLA isomers could reduce cell proliferation （P 〈 0.05）, increase apoptotic rate （P 〈 0.05）, and increase obviously the transcriptional and protein levels of PPARy （P 〈 0.01）. The synchronism and correlation between the effects of CLA to PPARy and apoptotic proteins Bax, Bcl-2, Caspase 3 changes were found with the dose- and time-dependent manners. There was cooperative relation between the levels of PPARy and the rates of Bax/Bcl-2, Caspase 3 （small fragment） by experiments of PPARy inhibitor GW9662 and ligand Rosiglitazone. Conclusion： The apoptotic pathway of PPARy-Bcl-2-Caspase 3 signaling was found. The C9, t11-CLA and tl0, c12-CLA could inhibit MCF-7 cell proliferation and promote apoptosis via activating PPARy-Bcl-2-Caspase 3 pathway. CLA may be a kind of activator of PPARv.

Soy isoflavone extracts stimulate the growth of nude mouse xenografts bearing estrogen-dependent human breast cancer cells(MCF-7)

We explored the effects of different lifetime exposures to soy isoflavone extracts on the growth of estrogen- dependent human breast cancer cells （MCF-7） implanted into athymic mice of different ovarian statuses. The athymic mice, ovariectomized or not, were implanted with MCF-7 cells. Mice were fed with low, moderate and high doses of soy isoflavone extract, at dietary concentrations of 6.25, 12.5 and 25 g/kg, in different reproductive models, respectively. The expression of ki-67 was detected by immunohistochemistry, pS2 expression in tumors was analyzed by real-time PCR. Estrogen level in the serum was measured by chemiluminescence enzyme im- munoassay. Total genistein and daidzein levels in serum and urine were determined by liquid chromatography- electrospray tandem mass spectrometry （LC-ES/MS/MS）. In Group A, on week 4, nude mice were exposed to different doses of soy iosflavone extracts. In Group B, the experimental diets were given to the nude mice follow- ing ovariectomy and tumor implantation. In both groups, 6.25 and 12.5 g/kg soy isoflavone extracts stimulated the growth of MCF-7 xenografts, increased pS2 expression, proliferation and estrogen level in serum. In both Group B （postmenopausal mouse model） and Group C （premenopausal mouse model）, soy isoflavone extracts at doses of 6.25 and 12.5 g/kg showed stimulatory effects on the growth of MCF-7 tumors. In conclusion, administration of soy isoflavone extracts at doses of 6.25 and 12.5 g/kg during adolescence or later in life stimulated tumor growth in both menopausal and postmenopausal mouse models.

Breast Cancer MCF-7 Cell Spheroid Culture for Drug Discovery and Development

In vitro 3D cancer spheroids (tumoroids) exhibit a drug resistance profile similar to that found in solid tumors. 3D spheroid culture methods recreate more physiologically relevant microenvironments for cells. Therefore, these models are more appropriate for cancer drug screening. We have recently developed a protocol for MCF-7 cell spheroid culture, and used this method to test the effects of different types of drugs on this estrogen-dependent breast cancer cell spheroid. Our results demonstrated that MCF-7 cells can grow spheroid in medium using a low attachment plate. We managed to grow one spheroid in each well, and the spheroid can grow over a month, the size of the spheroid can grow over a hundred times in volume. Our targeted drug experimental results suggest that estrogen sulfotransferase, steroid sulfatase, and G protein-coupled estrogen receptor may play critical roles in MCF-7 cell spheroid growth, while estrogen receptors α and β may not play an essential role in MCF-7 spheroid growth. Organoids are the miniatures of in vivo tissues and reiterate the in vivo microenvironment of a specific organ, best fit for the in vitro studies of diseases and drug development. Tumoroid, developed from cancer cell lines or patients’ tumor tissue, is the best in vitro model of in vivo tumors. 3D spheroid technology will be the best future method for drug development of cancers and other diseases. Our reported method can be developed clinically to develop personalized drugs when the patient’s tumor tissues are used to develop a spheroid culture for drug screening.

木黄酮对MCF-7/HER-2细胞uPA表达影响

目的探讨植物化学物质染料木黄酮(genistein)抗HER-2/neu高表达乳腺癌血管生成的分子机制。方法采用基因转染技术建立HER-2/neu高表达MCF-7乳腺癌细胞(命名为MCF-7/HER-2),5×10-5mol/L染料木黄酮处理MCF-7/HER-2细胞24,48,72 h后,应用western bolt、免疫沉淀、RT-PCR及激酶活性分析法检测genistein对MCF-7/HER-2乳腺癌细胞尿激酶型纤维蛋白溶酶原激活剂(urokinase-type plasminogen activator,uPA)表达、HER-2/neu受体蛋白磷酸化水平及蛋白酪氨酸激酶(PTK)活性变化。结果MCF-7/HER-2细胞uPA的mRNA和蛋白表达量比MCF-7细胞uPA的mRNA和蛋白表达量高,HER-2/neu受体蛋白磷酸化水平和PTK活性增加,染料木黄酮处理MCF-7/HER-2细胞后,uPA的mRNA和蛋白表达量下调,HER-2/neu受体蛋白磷酸化水平降低,PTK活性下降,且这种作用具有时效性。结论染料木黄酮能下调MCF-7/HER-2细胞HER-2/neu受体的PTK活性和蛋白磷酸化水平,抑制uPA表达,这可能是染料木黄酮抗乳腺癌血管生成的分子机制之一。

QCM Detection of Adhesion, Spreading and Proliferation of Human Breast Cancer Cells (MCF-7) on a Gold Surface

The quartz crystal microbalance （QCM） was used to monitor the one-day incubation of human breast cancer cells （MCF-7） on the gold electrode. In combination with an optical microscope simulation experiment, the cell-population pictures at various stages, the QCM responses to the cells＇ adhesion, spreading and proliferation on the electrode surface were discussed. The △f0 and △R1 responses were found mainly from mixed effects of viscodensity and surface stress, and in proportion to the cell coverage, rather than to the number of cells at the electrode. The significant fore-and-aft changes in cyclic voltammetry and electrochemical impedance spectroscopy of the ferri-ferrocyanide redox couple also proved that the cells were adhesion to the gold surface.

REVERSION OF MULTIDRUG RESISTANCE IN THE P-GLYCOPROTEIN POSITIVE BREAST CANCER CELL LINE(MCF-7/ADR) BY INTRODUCTION OF HAMMERHEAD RIBOZYME

A hammerhead ribozyme which site-specifically cleaved the GUC position in canon 880 of the mdr1 mRNA was designed. The target site was chosen between the two ATP binding sites, which may be important for the function of the P-Gp as an ATP-dependent pump. A DNA sequence encoding the ribozyme gene was then incorporated into a eukaryotic expression vector (pH Apr-1 neo) and transfected into the breast cancer cell line MCF-7/Adr, which is resistant to adriamycin and expresses the MDR phenotype. The ribozyme was stably expressed in the cell line by the RNA dot blotting assay. The result of Northern blot assay showed that the expressed ribozyme could decrease the level of mdrl mRNA expression by 83. 5 %; and the expressed ribozyme could inhibite the formation of p-glycoprotein detected by immuno- cy-tochemistry assay and could reduce the cell’s resistance to adrimycin; this means that the resistant cells were 1 000-fold more resistant than the parental cell line(MCF-7), whereas those cell clones that showed ribozyme expression were only 6-fold more resistant than the parental cell line. These results show that a potentially useful tool is at hand which may inactivate MDR1 mRNA and revert the multidrug resistance phenotype.

Cytotoxic Activity of <i>Thelesperma megapotamicum</i>Organic Fractions against MCF-7 Human Breast Cancer Cell Line

Thelesperma megapotamicum (Asteraceae) is commonly used in Argentine to treat various diseases (renal, digestive affections, and as anaesthesia). The present study showed the mechanisms involved “in vitro” cytotoxicity of T. megapotamicum Fractions. Five Fractions (F1 - F5) were separated by column chromatography (Silica gel) using hexane:diethyl ether as eluents. Viability was evaluated in Human breast carcinoma cell line (MCF-7) by staining with crystal violet. With respect to F1 Fraction treatment, the cell survival was 49.14% ± 8.87%, while the F2 and F3 ones exhibited a strong reduction of cell viability to only 26.35% ± 1.63% and 23.3%1 ± 0.53% of the control cell at 50 μg/ml, respectively. Apoptotic effect of these Fractions was detected using FITC-labeled Annexin V and propidium iodide binding assays and was confirmed by a higher proportion of apoptotic cells due to F2 and F3 treatments. T. megapotamicum active Fractions could facilitate the tumoral cells death by decreasing the activity of the enzyme Gamma-glutamyltranspeptidase and causing alteration in cell membrane sialoglycoconjugates and others involved anticancer mechanisms including apoptosis.

Study on Cisplatin Aggravating DNA Damage and Causing a High Apoptosis Rate on Breast Cancer MCF-7 Cells

[Objectives] To investigate the mechanism of DNA damage of cisplatin( DDP),a broad spectrum anticancer drug on breast cancer MCF-7 cells,and to study the mechanism of apoptosis induced by DDP.[Methods]MCF-7 cells were treated by DDP( 0 mg/L,2 mg/L,4 mg/L,6 mg/L,6 mg/L,and 10 mg/L) for 48 hours. MTT assay was used to detect the inhibitory effect of DDP on MCF-7 cells and IC50 value was calculated. Western blot was adopted to detect the expression of γ-H2 AX,which was the marker of DNA double stranded breaks( DSBs) and ATM( sensory molecules of DSBs),the apoptotic signal transduction molecule cleaved caspase-3,and the proteins associated with apoptosis calpain.[Results]DDP inhibited MCF-7 cell activity in a concentration-dependent manner and IC50 was 7. 57 mg/L. In contrast to the control group( without DDP treatment),MCF-7 cells with DDP treatment expressed more γ-H2 AX,ATM,cleaved caspase-3 and calpain.[Conclusions] DDP could inhibit the activity of breast cancer MCF-7 cells. Its mechanisms may be associated with inhibition of MCF-7 cell apoptosis,induction of DNA double strand breaking and the expression of pro-apoptotic protein up-regulation.

LMAN2在HR阳性乳腺癌组织中的表达与患者预后的关系及其对MCF-7细胞增殖和迁移的影响

目的:探究甘露糖结合凝集素2(LMAN2)在激素受体(HR)阳性乳腺癌组织中的表达水平与乳腺癌患者预后的关系及其对MCF-7细胞增殖和迁移的影响。方法:通过TCGA、Bc-GenExMiner、GEPIA和Kaplan-Meier Plotter数据库分析LMAN2在乳腺癌组织和正常乳腺组织中的差异性表达及其与患者预后的关系。采用小RNA干扰技术将si-LMAN2#1、si-LMAN2#2及si-NC转染至MCF-7细胞,将过表达LMAN载体(pc-LMAN)及空载体pcDNA3.1阴性对照(pc-NC)转染至MCF-7细胞,实验分为si-LMAN2#1、si-LMAN2#2、si-NC、pc-LMAN2和pc-NC组。通过qPCR和WB实验检测各组细胞中LMAN2 mRNA和蛋白的表达水平,CCK-8、克隆形成、Transwell迁移、WB等实验检测敲低和过表达LMAN 2对MCF-7细胞增殖、克隆形成、迁移及AKT信号通路相关蛋白表达的影响。结果:LMAN2在乳腺癌组织中的表达水平显著高于正常乳腺组织(P<0.001)。HR阳性乳腺癌组织中LMAN2表达水平显著高于HR阴性乳腺癌组织(P<0.001);LMAN2高表达与HR阳性乳腺癌患者不良预后有关联。敲低LMAN2可显著降低MCF-7细胞的增殖和迁移能力(P<0.01或P<0.001),过表达LMAN2可显著提高MCF-7细胞的增殖和迁移能力(均P<0.001)。敲低LMAN2组MCF-7细胞中PTEN和P21蛋白表达水平均显著升高,p-AKT蛋白表达水平显著降低(均P<0.01)。结论:LMAN2在乳腺癌组织和HR阳性乳腺癌组织中高表达,且与不良预后有关联。LMAN2高表达与MCF-7细胞增殖和迁移有关联,其作用机制可能涉及AKT信号通路。

2-aminoethyl Dihydrogen Phosphate as a Modulator of Proliferative and Apoptotic Effects in Breast Cancer Cell Lines

Background: Breast cancer is a type of cancer that affects more women throughout the world, in developing anddeveloped countries. 2-AEH2P is a phospholipid analog of cellular membrane, which makes it different from existing molecules fortheir absorption, stability and display anti-inflammatory, anti-proliferative and pro-apoptotic properties. Methods: MCF-7 humanbreast adenocarcinoma cells were treated with 2-AEH2P. The viability and adhesion cells were evaluated by MTT assay. Cell cyclephases, apoptosis, markers and mitochondrial potential were assessed by flow cytometry. Morphological ultrastructural analyzeswere performed by laser confocal microscopy. Results: MCF-7 Tumor cells acquired round shapes, lost cytoplasmic expansions,formed clusters in suspension and decreased significantly viability. There were changes in the morphology, membrane fragmentationand loss of cytoplasmic projection. The obtained concentrations for IC50% were 37.2;25.8;1.8 mM for periods of 24, 48 and 72 h,respectively. Changes in the distribution of cell population phases of the cell cycle showed an increase in fragmented DNA and anincrease in the G2/M phase. The expression β-gal showed proliferative reduction induced by 2-AEH2P. Laser confocal microscopyshowed changes in the mitochondrial membrane and alteration in distribution. Proliferative index of MCF-7 tumor cells treated with2-AEH2P decreased significantly when compared to fibroblast normal cells. The compound 2-AEH2P is a phospholipid withantiproliferative potential and apoptosis modulator.

Synthesis and Characterization of Trithiocarbonate-Organoclays Nanohybrids and Their Interaction with MCF-7 Cancer Cells

This work presents a new approach for the fabrication of organic/inorganic nanohybrids as anticancer drugs by an intercalation method using S,S-bis（α,α′-dimethyl-α″-acetic acid） （trithiocarbonate） as a modifier and two organoclays, such as reactive octadecylamine/MMT （montmorillonite） and non-reactive dimethyldidodecyl ammonium/MMT. The chemical and physical structures and the surface morphology of these covalently and non-covalently linked nanohybrids were investigated by FT-IR （Fourier translbrm infrared） spectroscopy, ^13C and ^29Si solid state NMR （nuclear magnetic resonance） spectroscopy, XRD （X-ray powder diffraction） and SEM （scanning electron microscopy） analyses, respectively. To evaluate the anticancer activities of the novel BATC/organoclay hybrids against MCF-7 breast cancer cells, a combination of different biochemical and biophysical testing techniques were used. Cell proliferation and cytotoxicity were detected in vitro using a real-time analysis. Cell death was confirmed by using apoptotic and necrotic analyses, the effects of which were detennined by the double staining and Annexin-V-FLUOS testing method. The results demonstrate that intercalated hybrid complexes containing a combination of various anticancer sites, such as free and complexed carboxyl, trithiocarbonate, amine and ammonium cations significantly induced cell death in breast cancer via their interactions with the DNA macromolecules of cancer cells by destroying the self-assemb｜ed structure of growing cells. Fabricated hybrid complexes may represent a new generation of effective and selective anticancer drug systems with a synthetic/natural origin for cancer chemotherapy.

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。

黄芪甲苷通过Bax/Bcl-2/Caspase-3信号通路诱导人乳腺癌MCF-7细胞凋亡的机制研究

目的观察黄芪甲苷(Astragaloside-IV,AS)抑制人乳腺癌MCF-7细胞增殖及诱导凋亡作用,并探讨其Bax/Bcl-2/Caspase-3信号通路作用机制。方法将MCF-7细胞分为空白对照组(AS,0μmol·L-1)和黄芪甲苷50、25、12.5μmol·L-1浓度组。采用CCK-8和台盼蓝计数法检测黄芪甲苷对MCF-7细胞增殖和生长曲线的影响;采用Hoechst 33258荧光染色法观察黄芪甲苷对MCF-7细胞凋亡形态学的影响;采用逆转录聚合酶链反应(RT-PCR)和Western Blot法分析黄芪甲苷对MCF-7细胞Bax、Bcl-2、Caspase-3、Cleaved Caspase-3 mRNA及蛋白表达的影响。结果与空白对照组比较,黄芪甲苷25、50μmol·L-1组MCF-7细胞增殖明显被抑制(P<0.01),生长曲线(2~7 d)显著减缓(P<0.05,P<0.01),细胞凋亡明显增多;RT-PCR和Western Blot试验结果发现黄芪甲苷25、50μmol·L-1组MCF-7细胞Bax、Caspase-3 mRNA和蛋白表达水平显著上调(P<0.01),Cleaved Caspase-3蛋白表达水平升高(P<0.01),Bcl-2 mRNA和蛋白表达水平明显下调(P<0.01)。结论黄芪甲苷可抑制人乳腺癌MCF-7细胞增殖,诱导其凋亡,其作用机制可能与调控Bax/Bcl-2/Caspase-3凋亡信号通路有关。

阿司匹林和塞来昔布对乳腺癌细胞MCF-7中COX-2及VEGF表达的影响

目的:通过研究非甾体类抗炎药物(NSAIDs)阿司匹林和塞来昔布对乳腺癌细胞MCF-7增殖及环氧化酶-2(COX-2)和血管内皮生长因子(VEGF)表达的影响,探讨NSAIDs的抗肿瘤作用。方法:MCF-7细胞根据所加药物不同分为不同浓度的阿司匹林(2.5、5.0和10.0mmol.L-1)组和塞来昔布(30、60和120μmol.L-1)组,以不含药物的培养液作为阴性对照组。MTT法检测不同时间(24、48和72h)各组细胞增殖抑制率,应用免疫组织化学SP法检测不同时间(24和48h)各组MCF-7细胞中COX-2及VEGF的表达。结果:①2.5 mmol.L-1阿司匹林作用48h、30μmol.L-1塞来昔布作用48和72 h及60μmol.L-1塞来昔布作用48 h细胞增殖抑制率与阴性对照组比较差异无显著性(P>0.05),其他各剂量组细胞增殖抑制率高于阴性对照组(P<0.05)。10.0 mmol.L-1阿司匹林作用24、48和72 h细胞增殖抑制率高于同一时间2.5 mmol.L-1阿司匹林组(P<0.05)。120μmol.L-1塞来昔布作用24、48和72 h细胞增殖抑制率高于同一时间30和60μmol.L-1塞来昔布组(P<0.05)。2.5、5.0和10.0 mmol.L-1阿司匹林作用72 h较作用24 h细胞增殖抑制率升高(P<0.05)。②MCF-7细胞中均有COX-2和VEGF蛋白表达,均定位于细胞浆,染色呈黄或棕黄色。③30μmol.L-1塞来昔布作用24、48 h和60μmol.L-1塞来昔布作48 h与阴性对照组比较MCF-7中COX-2和VEGF表达差异无显著性(P>0.05),其他各剂量组细胞中COX-2和VEGF表达均低于阴性对照组(P<0.05)。10.0 mmol.L-1阿司匹林作用24和48 h细胞中COX-2和VEGF表达低于同一时间2.5和5.0 mmol.L-1阿司匹林组(P<0.05)。120μmol.L-1塞来昔布作用24和48 h细胞中COX-2和VEGF表达低于同一时间30μmol.L-1塞来昔布组(P<0.05)。10.0 mmol.L-1阿司匹林和120μmol.L-1塞来昔布作用48 h较作用24 h细胞中COX-2和VEGF表达降低(P<0.05)。结论:阿司匹林和塞来昔布均有抑制乳腺癌细胞MCF-7增殖的作用,同时亦能抑制细胞中COX-2和VEGF的表达,上述抑制作用随药物浓度的增加、作用时间的延长而增强。

不同化疗方案对裸鼠MCF-7乳腺癌移植瘤PCNA和Bcl-2表达的影响

目的:研究不同化疗方案对乳腺癌组织PCNA和Bcl-2的影响,探讨二者与化疗的关系及评价疗效的价值。方法:制备MCF-7乳腺癌荷瘤裸鼠模型,化疗后观察移植瘤病理组织学疗效,用免疫组化SP法显示乳腺癌组织PCNA和Bcl-2表达情况。结果:(1)各化疗组瘤组织PCNA表达显著低于对照组(P<0.05),且NP、TP和Xeloda组显著低于CMF、CAF组(P<0.05)。PCNA表达与病理疗效显著相关(P=0.001)。(2)CAF、NP、TP和Xeloda化疗组Bcl-2蛋白表达显著高于对照组(P<0.05),且TP组显著高于CMF、CAF组(P<0.05)。Bcl-2表达与病理疗效无显著相关性(P=0.093)。结论:化疗可降低乳腺癌组织PCNA表达,并增强Bcl-2的表达,且不同化疗方案对二者影响的差异有显著性。PCNA可作为评价乳腺癌化疗效果的参考指标,对选择化疗方案可能有指导意义。

辛伐他汀抑制人乳腺癌MCF-7细胞内多能干细胞标志物Oct3/4 Nanog和Sox-2表达

目的:研究辛伐他汀(simvastatin,SIM)对人乳腺癌MCF-7细胞内多能干细胞标志物Oct3/4、Nanog和Sox-2表达的影响。方法:应用实时荧光定量聚合酶链式反应(qRT-PCR)技术、免疫荧光染色方法,流式细胞仪和免疫印迹(Western blot)方法检测SIM对MCF-7细胞内多能干细胞标志物表达的影响。结果:qRT-PCR结果显示,10、50和100μmol/L SIM作用于MCF-7细胞48h后,能显著抑制细胞内Oct3/4、Nanog和Sox-2基因表达,与对照组相比,差异有统计学意义(P<0.05),而SIM 1μmol/L浓度组和对照组相比差异无统计学意义(P>0.05)。SIM 50、100μmol/L浓度组和10μmol/L浓度组相比,抑制Oct3/4和Nanog的表达差异有统计学意义(P<0.05),而对Sox-2的表达抑制,SIM 10、50μmol/L和100μmol/L各浓度组间差异无统计学意义(P>0.05)。免疫荧光染色显示经10μmol/L SIM处理48 h后MCF-7细胞核内Oct3/4、Nanog和Sox-2蛋白表达减弱,部分细胞核无表达。流式细胞检测显示MCF-7细胞经10μmol/L SIM处理48 h后,Oct3/4阳性细胞数、Nanog阳性细胞数和Sox-2阳性细胞数显著减少(P<0.05),Western blot进一步证实经10μmol/L SIM处理48 h后MCF-7细胞核内Oct3/4、Nanog和Sox-2蛋白表达显著减少(P<0.05)。结论:SIM在体外能有效地抑制人乳腺癌MCF-7细胞内多能干细胞标志物Oct3/4、Nanog和Sox-2的表达,为SIM应用于癌症治疗提供实验依据。

Piperine suppresses growth and migration of human breast cancer cells through attenuation of Rac1 expression

Objective:To investigate the effect of piperine on human breast cancer cells.Methods:The effect of piperine on proliferation and migration of human breast cancer cells,MCF-7 and MDA-MB-231,was investigated using colony formation assays,wound healing assays,Matrigel migration assays,flow cytometry,RT-qPCR,and Western blotting assays.Results:Piperine inhibited the growth of MCF-7 and MDA-MB-231 cells and suppressed colony formation.Cell reduction at the G_(0)/G_(1) phase and cell arrest at the G_(2)/M phase were observed in breast cancer cells.However,the significant effect was only demonstrated in MDA-MB-231 cells.Moreover,cancer cell migration was suppressed by piperine at low concentration.RT-qPCR and Western blotting assays showed that piperine downregulated Rac1 gene and protein expression.Conclusions:Piperine could inhibit growth and migration of breast cancer cells by reducing Rac1 gene and protein expression.