Inactivated Sendai Virus Strain Tianjin Induces Apoptosis in Human Breast Cancer MDA-MB-231 Cells

Sendai virus strain Tianjin is a novel genotype. Here, we investigate the antitumor and proapoptotic effects of ultraviolet-inactivated Sendai virus strain Tianjin (UV-Tianjin) on human breast cancer MDA-MB-231 cells in vitro, as well as the involvement of the apoptotic pathway in the mechanism of UV-Tianjin-induced antitumor effects. MTT assays showed that treatment with UV-Tianjin dose-dependently inhibited the proliferation of MDAMB-231 cells but not normal MCF 10A breast epithelium cells. Hoechst staining and flow cytometric analysis revealed that UV-Tianjin induced apoptosis of MDA-MB-231 cells in a dose-dependent manner. Moreover, UV-Tianjin treatment resulted in reduction in the mitochondria membrane potential (MMP) and release of cytochrome complex (cyt c) via regulation of Bax and Bcl-2, as well as activation of caspase-9, caspase-3, Fas, FasL and caspase-8 in MDA-MB-231 cells. In summary, our study suggests that UV-Tianjin exhibits anticancer activity in human breast cancer MDA-MB-231 cells through inducing apoptosis, which may involve both the endogenous mitochondrial and exogenous death receptor pathways.     

Pectic-Oligoshaccharides from Apples Induce Apoptosis and Cell Cycle Arrest in MDA-MB-231 Cells,a Model of Human Breast Cancer

Background: The effects of plant products on cancer cells has become a field of major importance. Manysubstancesmay induce apoptosis in anti-cancer treatment. Pectins, a family of complex polysaccharides, andtheir degradation products may for exasmple exert apoptotic effects in cancer cells. Apples and citrus fruits arethe main sources of pectin which can be applied for anti-cancer research. The present study concerned an intactform of pectic-oligoshaccharide named pectic acid (poly galactronic acid). Materials and Methods: Inhibition ofcell proliferation assays (MTT), light microscopy, fluorescence microscopy (acridin orange/ethidium bromide),DNA fragmentation tests, cell cycle analysis, annexin PI and Western blotting methods were applied to evaluateapoptosis. Results: The results indicated that pectic acid inhibited cell growth and reduced cell attachment after24h incubation. This did not appear to be due to necrosis, since morphological features of apoptosis were detectedwith AO/EB staining and cell cycling was blocked in the sub-G1 phase. Annexin/PI and DNA fragmentationfindings indicated that apoptosis frequency increased after 24h incubation with pectic acid. In addition, the datashowed pectic acid induced caspase-dependent apoptosis. Conclusions: These data indicate that apple pectic acidwithout any modification could trigger apoptosis in MDA-MB-231 human breast cancer cells and has potentialto improve cancer treatment as a natural product.     

Neem Seed Oil Induces Apoptosis in MCF-7 and MDA MB-231Human Breast Cancer Cells

Background: In traditional Indian medicine, azadirachta indica (neem) is known for its wide range of medicinal properties. Various parts of neem tree including its fruit, seed, bark, leaves, and root have been shown to possess antiseptic, antiviral, antipyretic, anti-inflammatory, antiulcer, antimalarial, antifungal and anticancer activity. Materials and Methods: MCF-7 and MDA MB-231 cells were exposed to various concentrations of 2% ethanolic solution of NSO (1-30 μl/ml) and further processed for cell viability, cell cycle and apoptosis analysis. In addition, cells were analyzed for alteration in Mitochondrial Membrane Potential (MMP) and generation of Reactive Oxygen Species (ROS) using JC-1 and DCFDA staining respectively. Results: NSO give 50% inhibition at 10 μl/ml and 20 μl/ml concentration in MCF-7 and MDA MB-231 cells respectively and, arrests cells at G0/G1 phase in both the cell types. There was a significant alteration in mitochondrial membrane potential that leads to the generation of ROS and induction of apoptosis in NSO treated MCF-7 and MDA MB-231 cells. Conclusion: The results showed that NSO inhibits the growth of human breast cancer cells via induction of apoptosis and G1 phase arrest. Collectively these results suggest that NSO could potentially be used in the management of breast cancer.     

Glaucocalyxin A Activates FasL and Induces Apoptosis Through Activation of the JNK Pathway in Human Breast Cancer Cells

This study was conducted to analyze the molecular mechanisms responsible for anti-proliferation effects ofglaucocalyxin A in cultured MCF-7 and Hs578T breast cancer cells. The concentration that reduced cell viabilityto 50% (IC50) after 72 h treatment was derived and potential molecular mechanisms of anti-proliferationusing the IC50 were investigated as changes in cell cycle arrest and apoptosis. Gene and protein expressionchanges related to apoptosis were investigated by semi-quantitative RT-PCR and western blotting, respectively.Involvement of phosphorylated mitogen-activated protein kinases and JNK signaling in regulation of thesemolecules was characterized by western blotting. Cell viability decreased in a concentration-dependent mannerand the IC50 was determined as 1μM in MCF-7 and 4μM in HS578T cell. Subsequently, we demonstrated thatthe GLA-induced MCF-7 and Hst578T cell death was due to cell cycle arrest at the G2/M transition and wasassociated with activation of the c-jun N-terminal kinase (JNK) pathway. We conclude that GLA has the potentialto inhibit the proliferation of human breast cancer cells through the JNK pathway and suggest its applicationforthe effective therapy for patients with breast cancer.     

Celecoxib Inhibits Urokinase-Type Plasminogen Activator (uPA) Production in MDA-MB-231 Breast Cancer Cells

Summary Elevated urokinase-type plasminogen activator (uPA) expression in breast tumors predicts poor survival. We found celecoxib (25 μM) significantly reduced uPA protein and mRNA in MDA-MB-231 breast cancer cells following 72 h of treatment. Celecoxib also inhibited cell viability (12.5 and 25 μM) and induced G₂M arrest (25 μM). Therefore, celecoxib therapy for uPA positive breast cancer should be explored.     

5-aza-2'-deoxycytidine重新激活MDA-MB-231乳腺癌细胞雌激素受体基因的表达

目的　探讨 5 AZA CdR重新激活MDA MB 2 3 1乳腺癌细胞雌激素受体基因的表达。方法　采用免疫组织化学的方法 ,对用浓度为 2mg/L的 5 AZA CdR处理MDA MB 2 3 1乳腺癌细胞前后和阳性对照MCF 7乳腺癌细胞雌激素受体基因的表达情况进行检测分析。结果　 5 AZA CdR处理过的MDA MB 2 3 1乳腺癌细胞ER的阳性表达率明显增高 (P <0 .0 5 )。结论　 5 AZA CdR可以重新激活MDA MB 2 3 1乳腺癌细胞雌激素受体基因的表达     

全反式维甲酸诱导大鼠C6脑胶质瘤细胞凋亡的实验研究

目的: 探讨全反式维甲酸对大鼠C6脑胶质瘤细胞的增殖抑制及其分子机制。 方法: MTT法检测全反式维甲酸作用于大鼠C6脑胶质瘤细胞后,观察其对细胞增殖抑制率的影响。流式细胞仪观察肿瘤细胞周期及凋亡率的变化。电镜观察C6细胞超微结构变化。Western blot法在不同时间点对凋亡相关基因caspase-3活性蛋白产物的表达进行了检测。 结果: MTT结果表明ATRA对C6细胞的抑制作用具有时间和浓度依赖性。流式细胞仪检测证明与对照组相比,处理组C6细胞发生G₁期阻滞;S、G₂期细胞比例下降;细胞出现亚二倍峰,凋亡比例明显增加。电镜下全反式维甲酸作用72h后处理组C6细胞呈凋亡改变:如核固缩、染色质趋边凝聚。Western blot检测发现,处理组出现了caspase-3蛋白活性裂解片段。 结论: 全反式维甲酸抑制C6脑胶质瘤细胞生长,全反式维甲酸抑制脑胶质瘤的作用机理可能至少通过改变细胞周期分布、诱导凋亡来实现。     

Gambogenic Acid Induction of Apoptosis in a Breast Cancer Cell Line

Background: Gambogenic acid is a major active compound of gamboge which exudes from the Garciniahanburyi tree. Gambogenic acid anti-cancer activity in vitro has been reported in several studies, including anA549 nude mouse model. However, the mechanisms of action remain unclear. Methods: We used nude mousemodels to detect the effect of gambogenic acid on breast tumors, analyzing expression of apoptosis-relatedproteins in vivo by Western blotting. Effects on cell proliferation, apoptosis and apoptosis-related proteins inMDA-MB-231 cells were detected by MTT, flow cytometry and Western blotting. Inhibitors of caspase-3,-8,-9were also used to detect effects on caspase family members. Results: We found that gambogenic acid suppressedbreast tumor growth in vivo, in association with increased expression of Fas and cleaved caspase-3,-8,-9 and bax,as well as decrease in the anti-apoptotic protein bcl-2. Gambogenic acid inhibited cell proliferation and inducedcell apoptosis in a concentration-dependent manner. Conclusion: Our observations suggested that Gambogenicacid suppressed breast cancer MDA-MB-231 cell growth by mediating apoptosis through death receptor andmitochondrial pathways in vivo and in vitro.     

沉默LncRNA WT1-AS对三阴性乳腺癌细胞MDA-MB-231侵袭和迁移的影响

目的 探讨LncRNA WT1-AS对三阴性乳腺癌细胞MDA-MB-231侵袭和迁移的影响.方法 qRT-PCR检测WT1-AS在三阴性乳腺癌细胞中的表达及基因沉默的效率;Transwell实验检测WT1-AS对MDA-MB-231细胞侵袭能力的影响;划痕实验检测WT1-AS对MDA-MB-231细胞迁移能力的影响;W...     

Chalcone-3 Inhibits the Proliferation of Human Breast Cancer MDA-MB-231 Cell Line

Objective: Chalcone-3 has been shown to be cytotoxic and selective against luminal subtype breast cancer cell lines, which are suspected to occur through the mechanism of epidermal growth factor receptors (EGFR) inhibition. However, the cytotoxic effect has never been tested on cell strains from patients with triple negative breast cancer (TNBC), where EGFR expression is known to increase. This study aimed to identify the role of chalcone-3 in one of the downstream targets of EGFR as an antiproliferative agent. Methods: Chalcone-3 was examined for its effect on proliferation in human breast cancer MDA-MB-231 cell lines. The percentage of proliferation inhibition was analyzed using methyl-thiazol tetrazolium assay. Flow cytometry was used to analyze the population of cell cycle distribution and the expression of cyclin-D1 and pEGFR. Results: Chalcone-3 inhibited the proliferation of MDA-MB-231 cells in a dose and time-dependent manner with an IC50 value of 17.98±6.36 µg/mL by inducing cell cycle arrest at the G2/M phase. Flow cytometry assays showed that chalcone-3 significantly reduced the expression of pEGFR and cyclin-D1, contributing to cell cycle arrest. Conclusion: Chalcone-3 might have potential as an anti-proliferative drug to treat TNBC.     

p38 MAPK Signaling Mediates Mitochondrial Apoptosis in Cancer Cells Induced by Oleanolic Acid

Oleanolic acid (OA) is a nutritional component widely distributed in various vegetables. Although it has beenwell recognized for decades that OA exerts certain anti-tumor activity by inducing mitochondria-dependentapoptosis, it is still unclear that what molecular signaling is responsible for this effect. In this study, we employedcancer cell lines, A549, BXPC-3, PANC-1 and U2OS to elucidate the molecular mechanisms underlying OA antitumoractivity. We found that activation of MAPK pathways, including p-38 MAPK, JNK and ERK, was triggeredby OA in both a dose and time-dependent fashion in all the tested cancer cells. Activation was accompaniedby cleavage of caspases and PARP as well as cytochrome C release. SB203580 (p38 MAPK inhibitor), but notSP600125 (JNK inhibitor) and U0126 (ERK inhibitor), rescued the pro-apoptotic effect of OA on A549 and BXPC-3 cells. OA induced p38 MAPK activation promoted mitochondrial translocation of Bax and Bim, and inhibitedBcl-2 function by enhancing their phosphorylation. OA can induce reactive oxygen species (ROS)-dependentASK1 activation, and this event was indispensable for p38 MAPK-dependent apoptosis in cancer cells. In vivo,p38 MAPK knockdown A549 tumors proved resistant to the growth-inhibitory effect of OA. Collectively, weelucidated that activation of ROS/ASK1/p38 MAPK pathways is responsible for the apoptosis stimulated byOA in cancer cells. Our finding can contribute to a better understanding of molecular mechanisms underlyingthe antitumor activity of nutritional components.     

Down-Regulation of Notchl and NF-κB by Curcumin in Breast Cancer Cells MDA-MB-231

Objective:To test whether the down-regulation of Notch1 gene expression by curcumin could inhibit cell growth and induce apoptosis,which may be associated mechanistically with the down-regulation of NF-κB in breast cancer cells. Methods:Breast cancer cell lines MDA-MB-231 were cultured in vitro and treated with different dosages of curcumin(0,1.25,5.0,20.0μmol/L)for dose-dependent assay and different time(0,24,48,72 h)at the dosage of 5.0μmol/L for time course assay.The changes of the mRNA and protein expression of Notch1 and NF-κB were measured by RT-PCR and Western Blot,and MTT assay was used to measure the change of proliferation. Results:The mRNA and protein levels of Notch 1 and NF-κB were decreased significantly in human breast cancer cell line with the increase of dosage of curcumin(P＜0.05),and with the extension of time course(P＜0.05).These changes suggested a dose- and time-dependent manner.The proliferation rate of cells also was significantly inhibited(P＜0.05). Conclusion:The current results show that the Notch-1 signaling pathway is associated mechanistically with NF-κB activity during curcumin-induced cell growth inhibition and apoptosis of breast cancer cells.These results suggest that the down-regulation of Notch signaling by curcumin may be a novel strategy for the treatment of patients with breast cancer.     

Fenugreek Induced Apoptosis in Breast Cancer MCF-7 Cells Mediated Independently by Fas Receptor Change

Trigonella foenum in graecum (Fenugreek) is a traditional herbal plant used to treat disorders like diabetes,high cholesterol, wounds, inflammation, gastrointestinal ailments, and it is believed to have anti-tumor properties,although the mechanisms for the activity remain to be elucidated. In this study, we prepared a methanol extractfrom Fenugreek whole plants and investigated the mechanism involved in its growth-inhibitory effect on MCF-7 human breast cancer cells. Apoptosis of MCF-7 cells was evidenced by investigating trypan blue exclusion,TUNEL and Caspase 3, 8, 9, p53, FADD, Bax and Bak by real-time PCR assays inducing activities, in thepresence of FME at 65 μg/mL for 24 and 48 hours. FME induced apoptosis was mediated by the death receptorpathway as demonstrated by the increased level of Fas receptor expression after FME treatment. However,such change was found to be absent in Caspase 3, 8, 9, p53, FADD, Bax and Bak, which was confirmed by atime-dependent and dose-dependent manner. In summary, these data demonstrate that at least 90% of FMEinduced apoptosis in breast cell is mediated by Fas receptor-independently of either FADD, Caspase 8 or 3, aswell as p53 interdependently.     

Bishonokiol A Induces Multiple Cell Death in Human Breast Cancer MCF-7 Cells

Objective: A dimeric neolignan, bishonokiol A (BHNKA) isolated from Magnolia grandiflora, significantly inhibits the proliferation of human breast cancer cells. However, the exact mechanism of BHNKA induced breast cancer cell death is unknown. In this study, we investigated the pharmacological mechanism underlying BHNKA induced MCF-7 cell death. Methods: Cell viability measurement was performed by the MTT assay. Flow cytometry with PI staining, DAPI staining, and electron microscopy were used to analyze cellular death modes. In addition, western blotting, siRNA transfection, ATP assay, and fluorescence microscopy were used to determine the mechanism of BHNKA induced MCF-7 cell death. Results: BHNKA induced cell death by apoptosis, necroptosis and autophagy at the same concentration and time in MCF-7 cells, and electron microscopy confirmed these results. The mechanism of BHNKA triggered apoptosis and autophagy in MCF-7 cells was primarily due to an increase in the Bax/Bcl-2 ratio and simultaneous up-regulation of LC3-II protein expression, respectively. BHNKA induced necroptosis by activation of the RIP1-RIP3-MLKL necroptosis cascade, up-regulation of cyclophilin D (CypD) protein expression to stimulate ROS generation. We further demonstrated that siRNA-mediated down-regulation of CypD protected against BHNKA induced cell death. Conclusions: These results suggest that BHNKA may be a potential lead compound for development as an anti-breast cancer agent for induction of multiple cell death pathways.     

Fangchinoline Inhibits Cell Proliferation Via Akt/GSK-3beta/cyclin D1 Signaling and Induces Apoptosis in MDA-MB-231 Breast Cancer Cells

Fangchinoline (Fan) inhibits cell proliferation and induces apoptosis in several cancer cell lines. The effectsof Fan on cell growth and proliferation in breast cancer cells remain to be elucidated. Here, we show that Faninhibited cell proliferation in the MDA-MB-231 breast cancer cell line through suppression of the AKT/Gsk-3beta/cyclin D1 signaling pathway. Furthermore, Fan induced apoptosis by increasing the expression of Bax(relative to Bcl-2), active caspase 3 and cytochrome-c. Fan significantly inhibited cell proliferation of MDAMB-231 cells in a concentration and time dependent manner as determined by MTT assay. Flow cytometryanalysis demonstrated that Fan treatment of MDA-MB-231 cells resulted in cell cycle arrest at the G1 phase,which correlated with apparent downregulation of both mRNA and protein levels of both PCNA and cyclin D1.Further analysis demonstrated that Fan decreased the phosphorylation of AKT and GSK-3beta. In addition, Fanup-regulated active caspase3, cytochrome-c protein levels and the ratio of Bax/Bcl-2, accompanied by apoptosis.Taken together, these results suggest that Fan is a potential natural product for the treatment of breast cancer.     

ALEX1 Regulates Proliferation and Apoptosis in Breast Cancer Cells

Background: Arm protein lost in epithelial cancers, on chromosome X (ALEX) is a novel subgroup withinthe armadillo (ARM) family, which has one or two ARM repeat domains as opposed to more than six-thirteenrepeats in the classical Armadillo family members. Materials and Methods: In the study, we explore the biologicalfunctions of ALEX1 in breast cancer cells. Overexpression of ALEX1 and silencing of ALEX1 were performedwith SK-BR3 and MCF-7 cell lines. Cell proliferation and colony formation assays, along with flow cytometry,were carried out to evaluate the roles of ALEX1. Results: ALEX1 overexpression in SK-BR3 breast cancer cellsinhibited proliferation and induced apoptosis. Furthermore, depletion of ALEX1 in MCF-7 breast cancer cellsincreased proliferation and inhibited apoptosis. Additional analyses demonstrated that the overexpression ofALEX1 activated the intrinsic apoptosis cascades through up-regulating the expression of Bax, cytosol cytochromec, active caspase-9 and active caspase-3 and down-regulating the levels of Bcl-2 and mitochondria cytochrome c.Simultaneouly, silencing of ALEX1 inhibited intrinsic apoptosis cascades through down-regulating the expressionof Bax, cytosol cytochrome c, active caspase-9, and active caspase-3 and up-regulating the level of Bcl-2 andmitochondria cytochrome c. Conclusions: Our data suggest that ALEX1 as a crucial tumor suppressor genehas been involved in cell proliferation and apoptosis in breast cancer, which may serve as a novel candidatetherapeutic target.