scholarly journals Tamoxifen-Induced Rapid Death of MCF-7 Breast Cancer Cells Is Mediated via Extracellularly Signal-Regulated Kinase Signaling and Can Be Abrogated by Estrogen

Endocrinology ◽  
2007 ◽  
Vol 148 (6) ◽  
pp. 2764-2777 ◽  
Author(s):  
Aiping Zheng ◽  
Anu Kallio ◽  
Pirkko Härkönen
Keyword(s):  
Breast Cancer ◽  
Cell Death ◽  
Cancer Cells ◽  
Nuclear Localization ◽  
Breast Cancer Cells ◽  
Fluorescent Protein ◽  
Breast Cancer Cell Lines ◽  
Primary Role ◽  
17Β Estradiol ◽  
Mcf 7

Tamoxifen (Tam) is widely used in chemotherapy of breast cancer. It inhibits proliferation and induces apoptosis of breast cancer cells by estrogen receptor (ER)-dependent modulation of gene expression. In addition, recent reports have shown that Tam also has nongenomic effects. We previously reported induction of a rapid mitochondrial death program in breast cancer cells at pharmacological concentrations of Tam. Here we studied the upstream signaling events leading to mitochondrial disruption by Tam. We observed that 5 μm Tam rapidly induced sustained activation of ERK1/2 in ER-positive breast cancer cell lines (MCF-7 and T47D) and that PD98059 (inhibitor of ERK activation) was able to protect MCF-7 cells against Tam-induced death. These data suggest that activation of ERK has a primary role in the acute death response of the cells. In addition, inhibition of epidermal growth factor receptor (EGFR) opposed both Tam-induced ERK1/2 phosphorylation and cell death, which suggests that EGFR-associated mechanisms are involved in Tam-induced death. ERK1/2 phosphorylation was associated with a prolonged nuclear localization of ERK1/2 as determined by fluorescence microscopy with ERK2-green fluorescent protein construct. 17β-Estradiol was shown to exert a different kind of temporal pattern of ERK nuclear localization in comparison with Tam. Moreover, 17β-estradiol was found to oppose the rapid effects of Tam in MCF-7 and T47D cells but not in MDA-MB-231 cells, which implies a role for estrogen receptors in the protective effect of estrogen. The pure antiestrogen ICI182780 could not, however, prevent Tam-induced ERK1/2 phosphorylation, suggesting that the Tam-induced rapid cell death is primarily ER-independent or mediated by ICI182780 insensitive nongenomic mechanisms.

scholarly journals A radiosensitizer, gallotannin-rich extract from Bouea macrophylla seeds, inhibits radiation-induced epithelial-mesenchymal transition in breast cancer cells

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Jiraporn Kantapan ◽  
Siwaphon Paksee ◽  
Aphidet Duangya ◽  
Padchanee Sangthong ◽  
Sittiruk Roytrakul ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Dna Damage ◽  
Cell Death ◽  
Cancer Cells ◽  
Breast Cancer Cells ◽  
Epithelial Mesenchymal Transition ◽  
Breast Cancer Cell Lines ◽  
Mesenchymal Transition ◽  
Mammosphere Formation ◽  
Radiation Induced

Abstract Background Radioresistance can pose a significant obstacle to the effective treatment of breast cancers. Epithelial–mesenchymal transition (EMT) is a critical step in the acquisition of stem cell traits and radioresistance. Here, we investigated whether Maprang seed extract (MPSE), a gallotannin-rich extract of seed from Bouea macrophylla Griffith, could inhibit the radiation-induced EMT process and enhance the radiosensitivity of breast cancer cells. Methods Breast cancer cells were pre-treated with MPSE before irradiation (IR), the radiosensitizing activity of MPSE was assessed using the colony formation assay. Radiation-induced EMT and stemness phenotype were identified using breast cancer stem cells (CSCs) marker (CD24−/low/CD44+) and mammosphere formation assay. Cell motility was determined via the wound healing assay and transwell migration. Radiation-induced cell death was assessed via the apoptosis assay and SA-β-galactosidase staining for cellular senescence. CSCs- and EMT-related genes were confirmed by real-time PCR (qPCR) and Western blotting. Results Pre-treated with MPSE before irradiation could reduce the clonogenic activity and enhance radiosensitivity of breast cancer cell lines with sensitization enhancement ratios (SERs) of 2.33 and 1.35 for MCF7 and MDA-MB231cells, respectively. Pretreatment of breast cancer cells followed by IR resulted in an increased level of DNA damage maker (γ-H2A histone family member) and enhanced radiation-induced cell death. Irradiation induced EMT process, which displayed a significant EMT phenotype with a down-regulated epithelial marker E-cadherin and up-regulated mesenchymal marker vimentin in comparison with untreated breast cancer cells. Notably, we observed that pretreatment with MPSE attenuated the radiation-induced EMT process and decrease some stemness-like properties characterized by mammosphere formation and the CSC marker. Furthermore, pretreatment with MPSE attenuated the radiation-induced activation of the pro-survival pathway by decrease the expression of phosphorylation of ERK and AKT and sensitized breast cancer cells to radiation. Conclusion MPSE enhanced the radiosensitivity of breast cancer cells by enhancing IR-induced DNA damage and cell death, and attenuating the IR-induced EMT process and stemness phenotype via targeting survival pathways PI3K/AKT and MAPK in irradiated breast cancer cells. Our findings describe a novel strategy for increasing the efficacy of radiotherapy for breast cancer patients using a safer and low-cost natural product, MPSE.

scholarly journals Doxorubicin resistance mediated by cytoplasmic macrophage colony-stimulating factor is associated with switch from apoptosis to autophagic cell death in MCF-7 breast cancer cells

2016 ◽  
Vol 241 (18) ◽  
pp. 2086-2093 ◽  
Author(s):  
Mengxia Zhang ◽  
Hailiang Zhang ◽  
Fan Tang ◽  
Yuhua Wang ◽  
Zhongcheng Mo ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cell Death ◽  
Cancer Cells ◽  
Breast Cancer Cells ◽  
Colony Stimulating Factor ◽  
Doxorubicin Resistance ◽  
Macrophage Colony Stimulating Factor ◽  
Macrophage Colony ◽  
Stimulating Factor ◽  
Mcf 7

Macrophage colony-stimulating factor is a vital factor in maintaining the biological function of monocyte–macrophage lineage. It is expressed in many tumor tissues and cancer cells. Recent findings indicate that macrophage colony-stimulating factor might contribute to chemoresistance, but the precise mechanisms are unclear. This study was to explore the effect of macrophage colony-stimulating factor on doxorubicin resistance in MCF-7 breast cancer cells and the possible mechanism. In the study, the human breast cancer cells, MCF-7, were transfected with macrophage colony-stimulating factor. We document that cytoplasmic macrophage colony-stimulating factor induces doxorubicin resistance and inhibits apoptosis in MCF-7 cells. Further studies demonstrated that cytoplasmic macrophage colony-stimulating factor-mediated apoptosis inhibition was dependent on the activation of PI3K/Akt/Survivin pathway. More importantly, we found that macrophage colony-stimulating factor-induced autophagic cell death in doxorubicin-treated MCF-7 cells. Taken together, we show for the first time that macrophage colony-stimulating factor-induced doxorubicin resistance is associated with the changes in cell death response with defective apoptosis and promotion of autophagic cell death.

scholarly journals ARTEMISININ MODULATING EFFECT ON HUMAN BREAST CANCER CELL LINES WITH DIFFERENT SENSITIVITY TO CYTOSTATICS

2017 ◽  
Vol 39 (1) ◽  
pp. 25-29 ◽  
Author(s):  
V F Chekhun ◽  
N Yu Lukianova ◽  
T Borikun ◽  
T Zadvornyi ◽  
A Mokhir
Keyword(s):  
Breast Cancer ◽  
Drug Resistance ◽  
Cancer Cells ◽  
Breast Cancer Cells ◽  
Iron Homeostasis ◽  
Chemotherapeutic Agents ◽  
Fold Change ◽  
Breast Cancer Cell Lines ◽  
Cellular Iron ◽  
Mcf 7

Aim: To explore effects of Artemisinin on a series of breast cancer cells with different sensitivity to typical cytotoxic drugs (doxorubicin — Dox; cisplatin — DDP) and to investigate possible artemisinin-induced modification of the mechanisms of drug resistance. Materials and Methods: The study was performed on wild-type breast cancer MCF-7 cell line (MCF-7/S) and its two sublines MCF-7/Dox and MCF-7/DDP resistant to Dox and DDP, respectively. The cells were treated with artemisinin and iron-containing magnetic fluid. The latter was added to modulate iron levels in the cells and explore its role in artemisinin-induced effects. The MTT assay was used to monitor cell viability, whereas changes of expression of selected proteins participating in regulation of cellular iron homeostasis were estimated using immunocytochemical methods. Finally, relative expression levels of miRNA-200b, -320a, and -34a were examined by using qRT-PCR. Results: Artemisinin affects mechanisms of the resistance of breast cancer cells towards both Dox and DDP at sub-toxic doses. The former drug induces changes of expression of iron-regulating proteins via different mechanisms, including epigenetic regulation. Particularly, the disturbances in ferritin heavy chain 1, lactoferrin, hepcidin (decrease) and ferroportin (increase) expression (р ≤ 0.05) were established. The most enhanced increase of miRNA expression under artemisinin influence were found for miRNA-200b in MCF-7/DDP cells (7.1 ± 0.98 fold change), miRNA-320a in MCF-7/Dox cells (2.9 ± 0.45 fold change) and miRNA-34a (1.7 ± 0.15 fold change) in MCF-7/S cells. It was observed that the sensitivity to artemisinin can be influenced by changing iron levels in cells. Conclusions: Artemisinin can modify iron metabolism of breast cancer cells by its cytotoxic effect, but also by inducing changes in expression of iron-regulating proteins and microRNAs (miRNAs), involved in their regulation. This modification affects the mechanisms that are implicated in drug-resistance, that makes artemisinin a perspective modulator of cell sensitivity towards chemotherapeutic agents in cancer treatment.

Effet radiosensibilisateur de l'acide linoléique conjugué chez les cellules cancéreuses du sein MCF-7 et MDA-MB-231

2004 ◽  
Vol 82 (2) ◽  
pp. 94-102 ◽  
Author(s):  
Geneviève Drouin ◽  
Annie Douillette ◽  
Pierre Lacasse ◽  
Benoit Paquette
Keyword(s):  
Breast Cancer ◽  
Linoleic Acid ◽  
Cancer Cells ◽  
Conjugated Linoleic Acid ◽  
Breast Cancer Cells ◽  
Fold Increase ◽  
Breast Cancer Cell Lines ◽  
Apoptotic Pathways ◽  
Induced Apoptosis ◽  
Mcf 7

Apoptotic pathways in breast cancer cells are frequently altered, reducing the efficiency of radiotherapy. Conjugated linoleic acid (CLA), known to trigger apoptosis, was tested as radiosensitizer in breast cancer cells MCF-7 and MDA-MB-231. The CLA-mix, made up of the isomers CLA-9cis 11trans and CLA-10trans 12cis, was compared to three purified isomers, i.e., the CLA-9cis 11cis, CLA-9cis 11trans, and CLA-10trans 12cis. Using the apoptotic marker YO-PRO®-1, the CLA-9cis 11cis at 50 µmol/L turned out to be the best apoptotic inducer leading to a 10-fold increase in MCF-7 cells and a 2,5-fold increase in MDA-MB-231 cells, comparatively to the CLA-mix. Contrary to previous studies on colorectal and prostate cancer cells, CLA-10trans 12cis does not lead to an apoptotic response on breast cancer cell lines MCF-7 and MDA-MB-231. Our results also suggest that the main components of the CLA-mix (CLA-9cis 11trans and CLA-10trans 12cis) are not involved in the induction of apoptosis in the breast cancer cells studied. A dose of 5 Gy did not induce apoptosis in MCF-7 and MDA-MB-231 cells. The addition of CLA-9cis 11cis or CLA-mix has allowed us to observe a radiation-induced apoptosis, with the CLA-9cis 11cis being about 8-fold better than the CLA-mix. CLA-9cis 11cis turned out to be the best radiosensitizer, although the isomers CLA-9cis 11trans and CLA-10trans 12cis have also reduced the cell survival following irradiation, but using a mechanism not related to apoptosis. In conclusion, the radiosensitizing property of CLA-9cis 11cis supports its potential as an agent to improve radiotherapy against breast carcinoma.Key words: breast cancer, conjugated linoleic acid (CLA), radiotherapy, apoptosis.

Methotrexate induced cell death mechanisms in MCF-7 adenocarcinoma breast cancer cells: Enhanced cytotoxicity following dff45-siRNA pre-treatment

Synergy ◽  
2018 ◽  
Vol 7 ◽  
pp. 10-16
Author(s):  
Fatemeh Kiani ◽  
Negin Rasouli ◽  
Tahereh Kashkoolinejad ◽  
Shahrokh Safarian ◽  
Seyed Jalal Zargar ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cell Death ◽  
Cancer Cells ◽  
Breast Cancer Cells ◽  
Pre Treatment ◽  
Cell Death Mechanisms ◽  
Mcf 7

scholarly journals HDAC3–ERα Selectively Regulates TNF-α-Induced Apoptotic Cell Death in MCF-7 Human Breast Cancer Cells via the p53 Signaling Pathway

Cells ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 1280
Author(s):  
Seung-Ho Park ◽  
Hyunhee Kim ◽  
Sungmin Kwak ◽  
Ji-Hoon Jeong ◽  
Jangho Lee ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cell Death ◽  
Cancer Cells ◽  
Human Breast Cancer ◽  
Breast Cancer Cells ◽  
Apoptotic Cell ◽  
Human Breast Cancer Cells ◽  
Human Breast ◽  
Tnf Α ◽  
Mcf 7

Tumor necrosis factor-α (TNF-α) plays a significant role in inflammation and cancer-related apoptosis. We identified a TNF-α-mediated epigenetic mechanism of apoptotic cell death regulation in estrogen receptor-α (ERα)-positive human breast cancer cells. To assess the apoptotic effect of TNF-α, annexin V/ propidium iodide (PI) double staining, cell viability assays, and Western blotting were performed. To elucidate this mechanism, histone deacetylase (HDAC) activity assay and immunoprecipitation (IP) were conducted; the mechanism was subsequently confirmed through chromatin IP (ChIP) assays. Finally, we assessed HDAC3–ERα-mediated apoptotic cell death after TNF-α treatment in ERα-positive human breast cancer (MCF-7) cells via the transcriptional activation of p53 target genes using luciferase assay and quantitative reverse transcription PCR. The TNF-α-induced selective apoptosis in MCF-7 cells was negatively regulated by the HDAC3–ERα complex in a caspase-7-dependent manner. HDAC3 possessed a p53-binding element, thus suppressing the transcriptional activity of its target genes. In contrast, MCF-7 cell treatment with TNF-α led to dissociation of the HDAC3–ERα complex and substitution of the occupancy on the promoter by the p53–p300 complex, thus accelerating p53 target gene expression. In this process, p53 stabilization was accompanied by its acetylation. This study showed that p53-mediated apoptosis in ERα-positive human breast cancer cells was negatively regulated by HDAC3–ERα in a caspase-7-dependent manner. Therefore, these proteins have potential application in therapeutic strategies.

scholarly journals A Combination of an Antimitotic and a Bromodomain 4 Inhibitor Synergistically Inhibits the Metastatic MDA-MB-231 Breast Cancer Cell Line

2019 ◽  
Vol 2019 ◽  
pp. 1-13 ◽  
Author(s):  
Thandi Mqoco ◽  
André Stander ◽  
Anna-Mart Engelbrecht ◽  
Anna M Joubert
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Cell Line ◽  
Cancer Cell ◽  
Breast Cancer Cell ◽  
Breast Cancer Cells ◽  
Chemotherapeutic Agents ◽  
Breast Cancer Cell Lines ◽  
Mcf 7

Current chemotherapeutic agents have many side effects and are toxic to normal cells, providing impetus to identify agents that can effectively eliminate tumorigenic cells without damaging healthy cells. The aim of this study was to examine whether combining a novel BRD4 inhibitor, ITH-47, with the antimitotic estradiol analogue, ESE-15-ol, would have a synergistic effect on inhibiting the growth of two different breast cancer cell lines in vitro. Our docking and molecular dynamics studies showed that compared to JQ1, ITH-47 showed a similar binding mode with hydrogen bonds forming between the ligand nitrogens of the pyrazole, ASN99, and water of the BRD4 protein. Data from cell growth studies revealed that the GI50 of ITH-47 and ESE-15-ol after 48 hours of exposure was determined to be 15 μM and 70 nM, respectively, in metastatic MDA-MB-231 breast cancer cells. In tumorigenic MCF-7 breast cancer cells, the GI50 of ITH-47 and ESE-15-ol was 75 μM and 60 nM, respectively, after 48 hours of exposure. Furthermore, the combination of 7.5 μM and 14 nM of ITH-47 and ESE-15-ol, respectively, resulted in 50% growth inhibition of MDA-MB-231 cells resulting in a synergistic combination index (CI) of 0.7. Flow cytometry studies revealed that, compared to the control, combination-treated MDA-MB-231 cells had significantly more cells present in the sub-G1 phase and the combination treatment induced apoptosis in the MDA-MB-231 cells. Compared to vehicle-treated cells, the combination-treated cells showed decreased levels of the BRD4, as well as c-Myc protein after 48 hours of exposure. In combination, the selective BRD4 inhibitor, ITH-47, and ESE-15-ol synergistically inhibited the growth of MDA-MB-231 breast cancer cells, but not of the MCF-7 cell line. This study provides evidence that resistance to BRD4 inhibitors may be overcome by combining inhibitors with other compounds, which may have treatment potential for hormone-independent breast cancers.

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