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.

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.

18β-glycyrrhetinic Acid-induced Apoptosis and Relation with Intracellular Ca^2＋ Release in Human Breast Carcinoma Cells

To study the effects of 18β-glycyrrhetinic acid (GA) on proliferation inhibition, apoptotic induction, and the relationship between GA-induced apoptosis and intracellular Ca^2+ concentration in human breast carcinoma (MCF-7) cells. Methods: After MCF-7 cells were treated with GA at the concentrations from 50 μmol/L to 250 μmol/L for 24 h, cell viability of proliferation was as sessed by MTTassay. After the cells were treated with 100 μmol/L, 150 μmol/L, and 200 μmol/L GA for 24 h, the rates of cell apoptosis were examined by terminal deoxynucleotide transferase mediated dUTP nick-end-labeling method and flow cytometry with Annexin V/propidium iodide fluorescent stain. After the cells treated with 150 μmol/L GA for 24 h, intracellular Ca^2+ concentration was measured by Fure-2 fluorescein load method. Results: After the cells were treated with GA at the concentrations from 100 μmol/L to 250 μmol/L, the rates of proliferative inhibition were increased significantly (P<0.05 and P<0.01) in a dosedependent fashion. IC50 of the proliferation inhibition was 234.33 μmol/L. Treated with 100 μmol/L, 150 μmol/L, and 200 μmol/L, the rates of cell apoptosis were increased significantly (P<0.01). Intracellular Ca^2+ concentration after treatment with GA was higher evidently than that of control (P<0.05). Conclusion: 18β-glycyrrhetinic acid has the effects of the proliferation inhibition and the apoptotic induction on MCF-7 cells. The rise of intracellular Ca^2+ level may be depended on apoptosis induced by GA in MCF-7 cells.

Effect of amlodipine on apoptosis of human breast carcinoma MDA-MB-231 cells

Objective: To elucidate the effects of amlodipine on the proliferation and apoptosis of human breast carcinoma MDA-MB-231 cells. Methods: Light microscopy was used to determine the effects of amlodipine on cell morphology; Flow cytometry was used to quantitate cells undergoing apoptosis; the expression of a cell cycle-related protein, proliferating cell nuclear antigen (PCNA) and an antiapoptosis protein, Bcl-2 were assessed by immunocytochemistry. Results: Amlodipine concentration of 8.25 μmol/L (1/2 of IC50) affected the morphology, decreased the expression of PCNA and Bcl-2 and induced apoptosis of human breast carcinoma MDA-MB-231 cells. Conclusion: The effect of amlodipine on the antiproliferation of human breast carcinoma MDA-MB-231 cells is related to inducement of apoptosis, and the decrease of the expression of Bcl-2 and PCNA may be the possible mechanism for proliferation inhibitory and inducement of apoptosis.

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.

毛酸浆内酯通过抑制STAT3诱导人乳腺癌MCF-7细胞凋亡

[目的]旨在探讨信号转导和转录激活因子3(STAT3)在毛酸浆内酯(PPB)诱导人乳腺癌MCF-7细胞凋亡中发挥的作用。[方法]采用荧光染色法分析PPB诱导MCF-7细胞凋亡;使用生物信息学方法预测PPB抗乳腺癌的潜在机制;采用噻唑蓝(MTT)法考察STAT3抑制剂S3I-201以及STAT3小干扰RNA(siRNA)对PPB抑制MCF-7细胞生长的作用;采用蛋白免疫印迹(Western Blot)法考察PPB单独处理或STAT3 siRNA预处理后对MCF-7细胞中STAT3、B淋巴细胞瘤-2(Bcl-2)、Bcl-2相关X蛋白(Bax)、半胱氨酸天冬氨酸蛋白酶8(Caspase8)、半胱氨酸天冬氨酸蛋白酶9(Caspase9)、细胞色素c(Cytochrome c)以及多聚ADP核糖聚合酶(PARP)蛋白表达的影响。[结果]MCF-7细胞经PPB作用后凋亡形态特征明显,凋亡比例上升;生物信息学结果显示PPB与乳腺癌疾病的共同靶点STAT3在乳腺癌组织中高表达,单基因GSEA结果提示STAT3高表达与凋亡信号通路呈负相关;Western Blot法检测结果显示PPB能够抑制STAT3的磷酸化;S3I-201抑制剂或siRNA敲降STAT3均能进一步促进PPB抑制MCF-7细胞生长;此外,敲降STAT3进一步增加PPB对促凋亡蛋白Bax、Cytochrome c、裂解的Caspase8(Cleaved-Caspase8)、裂解的Caspase9(Cleaved-Caspase9)以及裂解的PARP(Cleaved-PARP)的促进作用,并增加PPB对抗凋亡蛋白Bcl-2的抑制作用。[结论]PPB通过抑制STAT3诱导人乳腺癌MCF-7细胞凋亡。

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.

Inhibition of cell proliferation by siRNA targeting hPRLR in breast cancer MCF-7 cell line

Objective： To study the inhibition of proliferation of breast cancer by small interfering RNA（siRNA） targeting human prolactin （hPRLR） and the underlying mechanisms. Methods：The siRNA targeting hPRLR was chemically synthesized and transfected into MCF-7 cells, the expression of hPRLR was analyzed by real-time quantitive PCR, cell growth inhibition was measured with MTT assay, cell cycle of the transfected cells was examined by flow cytometry, meanwhile, expression of cyclin D1 was tested by semi-quantitative RT-PCR, Results：24 h after transfection with 100 nmol/L siRNA-PRLR, the expression of hPRLR mRNA was suppressed by 65%, cells in G1 phase increased, but cells in S phase decreased. Down regulated hPRLR expression exhibited significant inhibition in cell proliferation. And the expression of cyclin D 1 was down regulated. Conclusion：The results indicate that siRNA-hPRLR is a useful tool for silencing hPRLR expression and inhibiting cell proliferation in breast cancer MCF-7 cell line, and it may be a possible new approach for breast cancer gene therapy.

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.

Effect of Guizhi Fuling capsule and its extracts on human breast cancer cells proliferation

OBJECTIVE To evaluate the effect of Guizhi Fuling Capsule active pharmaceutical ingredient(API)and its fractions on human breast cancer cells proliferation by high-throughput screening assay.METHODS The crude fractions were obtained from the extraction and elution of the API of Guizhi Fuling Capsule,and 929 standard fractions were obtained by the optimal separation conditions.Sulforhodamine B(SRB)method was used to evaluate the effects of the Guizhi Fuling capsule API and929 kinds of fractions on the proliferation of human breast cancer cells MCF-7 and MDA-MB-231.RESULTS The Guizhi Fuling capsule API had a strong ability to inhibit the proliferation of MCF-7 cells at high concentration and the ability to inhibit MDA-MB-231 cells' proliferate at low concentration following 72 h treatment;some samples of 929 fractions(5μg·mL^(-1))was found to have a breast cancer cell growth inhibition rate above 50%,without toxicity on HUVECs proliferation.CONCLUSION The API of Guizhi Fuling capsule had significant cytotoxicity effects on these two human breast cancer cells,with significant concentration-and time-dependent manner.

Retinoic acid affects basic cellular processes and SOX2 and SOX18 expression in breast carcinoma cells

Genetic and molecular heterogeneity,together with intrinsic and acquired resistance to therapy,represent the major obstacles to the successful treatment of different types of breast carcinoma.Increasing evidence demonstrates that SOX transcription factors in breast carcinomas could act both as oncogenes and tumor suppressors and have been associated with tumor stage and grade,poor prognosis,and therapy resistance.Both SOX2 and SOX18 overexpression has been correlated with poor prognosis in breast carcinomas,and these genes are recognized as potential antitumor targets.Our aim was to evaluate the effect of retinoic acid(RA),a well-known cyto-differentiating agent,on breast carcinoma cells in vitro and to investigate the potential of RA treatment to modify the expression of SOX2 and SOX18 genes.By applying various experimental approaches,we evaluated the effect of RA on basic cellular processes in SK-BR-3 and MCF7 breast carcinoma cell lines.We have shown that RA inhibits cell growth,reduces the number of Ki-67 positive cells,and causes cell-cycle arrest.RA effect was more prominent in SK-BR-3 cell line that lacks SOX2 expression,including a higher decrease in cell viability,reduction in colony formation,and significant remodeling of cellular structure.We have shown that RA treatment led to the downregulation of SOX2 expression in MCF7 cells and to the reduction of SOX18 expression in both cell lines.By functional analysis,we showed that the anti-proliferative effect of RA in both cell lines was not based on the activity of stemness marker SOX2,pointing to a SOX2-independent mechanism of action.The ability of RA to reduce SOX2/SOX18 expression raises the possibility that these genes can be used as biomarkers to distinguish RA-responders from non-responders.Together,our study shows that the response of breast carcinoma cell lines to RA treatment may vary,highlighting that the development of RA-based therapy should consider differences in breast carcinoma subtypes.

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.

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.

苦参碱对人乳腺癌MCF-7细胞自噬及细胞凋亡的影响

目的:研究苦参碱对人乳腺癌MCF-7细胞自噬及凋亡的影响,并分析其机制,探索二者之间潜在的关系。方法:采用MTT法和Annexin V/PI双染法检测细胞增殖活力和凋亡率;自噬双标腺病毒法(mRFP-GFP-LC3)和透射电镜法检测细胞自噬水平;Western Blot检测自噬相关蛋白Beclin-1、LC3及凋亡相关蛋白Caspase-3、cleaved-Caspase-3、cleaved-Caspase-9的表达;运用自噬抑制剂(3-MA)和凋亡抑制剂(Z-VAD-FMK)对上述相关指标进行干预。结果:苦参碱在未加入抑制剂干预的情况下可显著抑制MCF-7细胞的增殖,提高凋亡率和自噬水平,可上调自噬相关蛋白Beclin-1、LC3和凋亡相关蛋白cleaved-Caspase-3、cleaved-Caspase9的表达(P<0.05或P<0.01)。加入自噬抑制剂(3-MA)后,细胞存活率显著降低,凋亡率显著升高(P<0.05);加入凋亡抑制剂(Z-VAD-FMK)后,自噬水平显著升高(P<0.05)。结论:苦参碱可诱导人乳腺癌MCF-7细胞凋亡和细胞自噬,二者之间可能存在着互相调控的关系。

基于PI3K/Akt/mTOR信号通路的苦参碱诱导人乳腺癌MCF-7细胞自噬及其机制的研究

目的 研究苦参碱对人乳腺癌MCF-7细胞自噬及其相关信号通路的影响,为苦参碱的抗肿瘤作用提供更多依据。方法 采用自噬双标腺病毒(mRFP-GFP-LC3)法、透射电镜法(TEM)检测给药后细胞自噬水平的变化;Western blot检测苦参碱对自噬相关蛋白LC3、Beclin-1,信号通路蛋白PI3K、p-PI3K、Akt、p-Akt、mTOR、p-mTOR表达水平的影响。结果 随着苦参碱浓度的上升,细胞中的自噬水平也在逐渐升高,自噬相关蛋白LC3-II/LC3-I、Beclin-1的表达量呈上升趋势,通路相关蛋白PI3K、Akt、mTOR无明显变化,p-PI3K、p-Akt、p-mTOR的表达量均呈现下降趋势。结论 苦参碱可剂量依赖性升高MCF-7细胞的自噬水平,机制可能与PI3K/Akt/mTOR介导的信号通路有关。

不同浓度丙泊酚对人乳腺癌雌激素受体阳性MCF-7细胞增殖、迁移及侵袭的影响

目的研究不同浓度丙泊酚对人乳腺癌雌激素受体阳性MCF-7细胞增殖、迁移及侵袭的影响。方法以人乳腺癌雌激素受体阳性MCF-7细胞为研究对象,随机将其分为3组,即P_(0)组(为空白对照)、P_(25)组(给予25μg/mL丙泊酚)和P_(50)组(给予50μg/mL丙泊酚)。对3组细胞分别进行克隆形成实验、Transwell细胞迁移实验、侵袭实验、划痕愈合实验,观察各组细胞的增殖、迁移、侵袭变化情况。采用Western blot法检测不同浓度丙泊酚对人乳腺癌胞Ki-67、PD-L1的蛋白表达水平的影响;RT-qPCR法检测不同浓度丙泊酚对Ki-67、PD-L1的RNA表达水平的影响。结果与P_(0)组比较,P_(50)组人乳腺癌雌激素受体阳性MCF-7细胞增殖、迁移及侵袭能力均升高,差异有统计学意义(P<0.05);与P_(25)组比较,差异无统计学意义(P>0.05)。与P_(0)组相比,P_(50)组PD-L1、Ki-67蛋白表达水平升高,差异有统计学意义(P<0.05),其中PD-L1表达随丙泊酚浓度的增高而增高;与P_(25)组比较,差异无统计学意义(P>0.05)。3组间PD-L1、Ki-67的RNA表达水平比较,差异均有统计学意义(P<0.001)。结论高浓度丙泊酚能促进人乳腺癌雌激素受体阳性MCF-7细胞增殖、侵袭、迁移能力,该变化与相关蛋白Ki-67、PD-L1表达增强有关。

Cytotoxicity screening of Melastoma malabathricum extracts on human breast cancer cell lines in vitro

Objective:To screen the cytotoxic activity of Melasloma malabathricum(M,malubathricum)against human breast carreer cell line(MCF-7)in vitro.Methods:A three steps extraction protocol using n-hexane,chloroform and methanol as the solvents systems was carried out on leaves,stems and flowers of M.nalabathricum.Dimethyl sulfoxide was used in extracts dilution and serial dilutions were conducted to obtain five different extract concentrations(100μg/mL,50μg/mL,25μg/mL,123μg/rnL and 6.25μg/mL).The evaluation of cell growth was determined using methylene blue assay.Results:Methanol extract from the leaves showed significant anticancer activity against MCF-7cell lines with the TC_(50)value of 7.14μg/ml while methanol and chloroform extract from the flowers exhibited a moderate activity towards MCF-7 cell line,with the IC_(50)value of 33.63μg/mL and 45.76μg/mL respectively after 72 h of treatment.Conclusions:The extracts from leaves and flowers of M.nulabatkricum showed promising anticancer activity toward human breast cancer cell lines with the lowest IC_(50)at 7.14μg/mL while the extracts from stems showed less growth inhibition activity.

Anticancer property of sediment actinomycetes against MCF-7 and MDA-MB-231 cell lines

Objective:To investigate the anticancer property of marine sediment actinomvceles against two different breast cancer cell lines.Methods:In vitro anticancer activity was carried out against breast(MCF-7 and MDA-MB-231)cancer cell lines.Partial sequences of the 16s rRNA gene,phylogenetic tree construction,multiple sequence analysis and secondary structure analysis were also carried out with the actinomycetes isolates.Results:Of the selected five actinomycete isolates,ACT01 and ACT02 showed the IC_(50)value with(10.13±0.92)and(22.34±5.82)μg/mL concentrations,respectively for MCF-7 cell line at 48 h,but ACT01 showed the minimum(18.54±2.49μg/mL)level of IC_(50)value with MDA-MB-231 cell line.Further,the 16s rRNA partial sequences of ACT01,ACT02,ACT03,ACT04 and ACT05 isolates were also deposited in NCBI data bank with the accession numbers of GQ478246,GQ478247,GQ478248,GQ478249 and GQ478250.respectively.The phylogenetic tree analysis showed that,the isolates of ACT02 and ACT03 were represented in groupⅠandⅢ,respectively,but ACT01 and ACT02 were represented in groupⅡ.The multiple sequence alignment of the actinomycete isolates showed that,the maximum identical conserved regions were identified with the nucleotide regions of 125 to 221st base pairs,65 to 119th base pairs and 55,48 and 31st base pairs.Secondary structure prediction of the 16s rRNA showed that,the maximum free energy was consumed with ACT03 isolate(-45.4 kkal/mol)and the minimum free energy was consumed with ACT04 isolate(-57.6 kkal/mol).Conclusions:The actinomycete isolates of ACT01 and ACT02(GQ478246 and GQ478247)which are isolated from sediment sample can be further used as anticancer agents against breast cancer cell lines.

Sensitivity Evaluation of Two Human Breast Cancer Cell Lines to Tamoxifen through Apoptosis Induction

Tamoxifen citrate (TAM) has been used to treat breast cancer in women for many years. The com-parative effects of TAM in inducing apoptosis were evaluated in estrogen receptor-positive (ER- positive MCF-7) and estrogen receptor-negative (ER-negative MDA-MB-231) human breast cancer cell lines in vitro in order to determine if these two cell lines differ in their sensitivity to TAM. Mi-tochondrial membrane permeability potential disruption was assessed in both cell lines by a lip-ophilic cationic dye (DePsipher assay, Trevigen, Inc.) utilizing fluorescence microscopy. Using this specific fluorochrome, we were able to associate mitochondrial membrane disruption to early, mid-, and late apoptotic cells. TAM induced cell death via apoptosis in both ER-positive and ER- negative cells, however, apoptosis induction was more pronounced in ER-positive MCF-7 compared to ER-negative MDA-MB-231 breast cancer cells. These findings may have some therapeutic use in the treatment of estrogen dependent and estrogen independent breast cancer.

Expression levels of PTK7, HER-2 and Mcm5 proteins in esophageal squamous cell carcinoma and their clinical prognostic value

Objective:To investigate the expression levels and clinical prognosis of tyrosine protein kinase-7(PTK7),human epidermal growth factor receptor 2(HER-2)and minichromosome maintenance protein 5(Mcm5)in esophageal squamous cell carcinoma(ESCC)value.Methods:180 patients with ESCC were enrolled as the study subjects.Tumor tissues were collected and 100 paracancerous tissues were randomly collected.The expression levels of PTK7,HER-2 and Mcm5 proteins were detected by immunohistochemical staining,and their clinical pathological features and prognosis.Relationship.Results:The positive rates of PTK7,HER-2 and Mcm5 in ESCC tissues were significantly higher than those in adjacent tissues(P<0.05).The positive rate of PTK7 in lymphatic metastasis was significantly higher than that in lymphatic metastasis(P<0.05).The tumor body diameter was greater than 2 cm,the TNM stage was stage III and IV,and the HER-2 positive rate of ESCC tissues with lymphatic metastasis was significantly increased(P<0.05).The positive rate of Mcm5 in stage III and IV and combined lymphatic metastasis ESCC was higher in TNM stage(P<0.05).The expression level of PTK7 in ESCC tissues was positively correlated with lymphatic metastasis(P<0.05).HER-2 was positively correlated with TNM stage and lymphatic metastasis(P<0.05).Mcm5 was positively correlated with tumor size,TNM stage and lymphatic metastasis(P<0.05).The tumor-free survival of PTK7,HER-2,and Mcm5-positive ESCC patients was significantly shorter than that of the negative group(P<0.05).Conclusion:The expression levels of PTK7,HER-2,and Mcm5 were significantly up-regulated in ESCC tissues,and high levels of HER-2 and Mcm5 predicted more severe pathological stage and lymphatic metastasis,and PTK7,HER-2,Mcm5 and worse.Prognosis is related.