Contribution of platelets to tumor aggressivity.

2012 ◽  
Vol 30 (15_suppl) ◽  
pp. e21156-e21156
Author(s):  
Judith Delage ◽  
Hong Li ◽  
He Lu ◽  
Lionel Cazin ◽  
Jeannette Soria ◽  
...  
Keyword(s):  
Platelet Aggregation ◽  
Cancer Cells ◽  
Antithrombin Iii ◽  
Factor Xa ◽  
Procoagulant Activity ◽  
Thrombin Inhibitors ◽  
Thrombin Inhibitor ◽  
Breast Cancer Cell Lines ◽  
Cancer Aggressiveness ◽  
Mcf 7

e21156 Background: The interaction between cancer and coagulation process has been shown since many years. The aim of our study is to understand the mechanisms implicated and to propose new therapeutic approaches. Methods: Two breast cancer cell lines were used: a very aggressive (MDA-MB231) and a much less aggressive (MCF-7). Platelet aggregation tests were done with washed platelets, normal or fibrin removed plasma and cancer cells (20 to 2.105 cells/ml). Procoagulant activity of cancer cells was studied. Aspirin, Apyrase (ADPase), a direct thrombin inhibitor (Hirudin), two Xa inhibitors (Fondaparinux, Rivaroxaban) were the inhibitors tested. Interaction between platelets and cancer cells was visualized by confocal microscopy. Angiogenic effect of supernatants from platelets-cancer cells co-incubation was investigated. Results: The data obtained show that a platelet aggregation is induced by cancer cells in the presence of a small amount of plasma. This aggregation depends on both the type and number of cancer cells. Aggressive MDA-MB231 cells have a more potent pro-aggregating activity than MCF-7. This aggregation appears to be due to thrombin generation since it is inhibited by Hirudin. Rivaroxaban, a direct inhibitor of factor Xa, inhibits platelets aggregation but not Fondaparinux, an indirect anti Xa inhibitor which binds to Antithrombin III. Aspirin and Apyrase have no effect. Moreover, the procoagulant activity of cancer cells with plasma is inhibited by Hirudin and Rivaroxaban but not by Fondaparinux. This suggests that the Fondaparinux-Antithrombin III complex cannot access to cell membrane-bound factor Xa. It may be due to its steric hindrance since thromboplastin induced coagulation is inhibited by Rivaroxaban but not by Fondaparinux. The confocal microscopic study shows that platelets protect tumor cells from immune attack via the formation from a protective envelope around cancer cells. Angiogenesis assays show that activation of platelets by cancer cells releases angiogenesis stimulating factors and cytokines. Conclusions: The present work confirms the crucial role of platelets in cancer aggressiveness and reveals that Rivaroxaban or Thrombin inhibitors could be efficient drugs to reduce cancer progression, metastasis and thrombosis.

Inhibition of Thrombin Generation in Plasma by Inhibitors of Factor Xa

1997 ◽  
Vol 78 (04) ◽  
pp. 1215-1220 ◽  
Author(s):  
D Prasa ◽  
L Svendsen ◽  
J Stürzebecher
Keyword(s):  
Thrombin Generation ◽  
Factor Xa ◽  
Thrombin Inhibitors ◽  
Thrombin Inhibitor ◽  
Thrombin Generation Assay ◽  
Ic50 Values ◽  
Fxa Inhibitor ◽  
20 Nm ◽  
Tick Anticoagulant Peptide ◽  
Inhibition Of Thrombin

SummaryA series of inhibitors of factor Xa (FXa) were investigated using the thrombin generation assay to evaluate the potency and specificity needed to efficiently block thrombin generation in activated human plasma. By inhibiting FXa the generation of thrombin in plasma is delayed and decreased. Inhibitor concentrations which cause 50 percent inhibition of thrombin generation (IC50) correlate in principle with the Ki values for inhibition of free FXa. Recombinant tick anticoagulant peptide (r-TAP) is able to inhibit thrombin generation with considerably low IC50 values of 49 nM and 37 nM for extrinsic and intrinsic activation, respectively. However, the potent synthetic, low molecular weight inhibitors of FXa (Ki values of about 20 nM) are less effective in inhibiting the generation of thrombin with IC50 values at micromolar concentrations.The overall effect of inhibitors of FXa in the thrombin generation assay was compared to that of thrombin inhibitors. On the basis of similar Ki values for the inhibition of the respective enzyme, synthetic FXa inhibitors are less effective than thrombin inhibitors. In contrast, the highly potent FXa inhibitor r-TAP causes a stronger reduction of the thrombin activity in plasma than the most potent thrombin inhibitor hirudin.

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.

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.

scholarly journals Osteoblast-conditioned medium promotes proliferation and sensitizes breast cancer cells to imatinib treatment

2007 ◽  
Vol 14 (1) ◽  
pp. 61-72 ◽  
Author(s):  
Marina Brama ◽  
Sabrina Basciani ◽  
Sara Cherubini ◽  
Stefania Mariani ◽  
Silvia Migliaccio ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Tyrosine Kinase ◽  
Cancer Cells ◽  
Conditioned Medium ◽  
Human Breast Cancer ◽  
Breast Cancer Cells ◽  
Breast Cancer Cell Lines ◽  
Imatinib Treatment ◽  
Human Breast ◽  
Mcf 7

Inhibition of platelet-derived growth factor receptor (PDGFR) signaling restricts the growth of human breast cancer in the bone of nude mice. We hypothesized that osteoblast-secreted substances may alter the response capacity of breast cancer cells to the PDGFRs tyrosine kinase inhibitor imatinib mesylate. We found that osteoblast-conditioned medium (OCM) increases the proliferation rate of the estrogen receptor negative (ER−) MDA-MB-231 and of the ER+ MCF-7 human breast cancer cell lines and the growth-promoting effect on ER+ cells is independent from estrogen. OCM significantly improved the dose- and the time-dependent sensitivity of the tumor cells to the anti-proliferative effect of imatinib. We also found that MDA-MB-231 and MCF-7 cells express the two PDGFRs subtypes, PDGFR-α and PDGFR-β, and OCM treatment increases the expression of the PDGFRs. Furthermore, imatinib inhibited the phosphorylation rate of its target tyrosine kinase receptors. We conclude that bone microenvironment, through osteoblast-secreted substances may cause estrogen-independent proliferation of breast cancer cells by a mechanism mediated by the induction of PDGFRs expression. The enhanced sensitivity of OCM-treated breast cancer cells to imatinib would justify investigation on the efficacy of imatinib in bone breast cancer metastasis.

Rheology of Cancer Cells With Different Metastatic Properties

2009 ◽  
Author(s):  
T. Yoshimoto ◽  
T. Ishikawa ◽  
N. Matsuki ◽  
H. Fujiwara ◽  
Y. Imai ◽  
...  
Keyword(s):  
Rheological Properties ◽  
Cancer Cells ◽  
Human Breast Cancer ◽  
Human Breast Cancer Cell ◽  
The Body ◽  
Breast Cancer Cell Lines ◽  
Human Breast ◽  
Cell Deformability ◽  
Distant Part ◽  
Mcf 7

Cancer is the leading cause of death in Japan as well as many other countries. One of the most serious problem of cancer is that cancer cells often migrate to a distant part of the body, referred to as metastasis. The rheological properties of cancer cells have been investigated by some reserchers [1,2]. However, the correlations between the metastasis and the rheological properties are still unclear, because of limited number of experimental cases reported so far. In this study, we used two kinds of human breast cancer cell lines, MCF-7 and KPL-4. It is known that KPL-4 has much higher metastatic property than MCF-7. The rheological properties of these cells were measured by a micropipette aspiration method [3,4]. By comparing Young’s modulus between two kinds of cancer cells, we discuss the correlations between the metastasis and the cell deformability.

scholarly journals Estrogen Withdrawal-Induced NF-κB Activity and Bcl-3 Expression in Breast Cancer Cells: Roles in Growth and Hormone Independence

2003 ◽  
Vol 23 (19) ◽  
pp. 6887-6900 ◽  
Author(s):  
M. A. Christine Pratt ◽  
Tanya E. Bishop ◽  
Dawn White ◽  
Gordon Yasvinski ◽  
Michel Ménard ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Dna Binding ◽  
Cancer Cells ◽  
Breast Cancer Cells ◽  
Breast Cancer Cell Lines ◽  
Stable Form ◽  
Estrogen Withdrawal ◽  
Hormone Independence ◽  
Mcf 7

ABSTRACT About one-third of breast cancers express a functional estrogen (β-estradiol [E2]) receptor (ER) and are initially dependent on E2 for growth and survival but eventually progress to hormone independence. We show here that ER+, E2-independent MCF-7/LCC1 cells derived from E2-dependent MCF-7 cells contain elevated basal NF-κB activity and elevated expression of the transcriptional coactivator Bcl-3 compared with the parental MCF-7 line. LCC1 NF-κB activity consists primarily of p50 dimers, although low levels of a p65/p50 complex are also present. The ER− breast cancer cell lines harbor abundant levels of both NF-κB complexes. In contrast, nuclear extracts from MCF-7 cells contain a significantly lower level of p50 and p65 than do LCC1 cells. Estrogen withdrawal increases both NF-κB DNA binding activity and expression of Bcl-3 in MCF-7 and LCC1 cells in vitro and in vivo. Tumors derived from MCF-7 cells ectopically expressing Bcl-3 remain E2 dependent but display a markedly higher tumor establishment and growth rate compared to controls. Expression of a stable form of IκBα in LCC1 cells severely reduced nuclear expression of p65 and the p65/p50 DNA binding heterodimer. Whereas LCC1 tumors in nude mice were stable or grew, LCC1(IκBα) tumors regressed after E2 withdrawal. Thus, both p50/Bcl-3- and p65/p50-associated NF-κB activities are activated early in progression and serve differential roles in growth and hormone independence, respectively. We propose that E2 withdrawal may initiate selection for hormone independence in breast cancer cells by activation of NF-κB and Bcl-3, which could then supplant E2 by providing both survival and growth signals.

The Effect of Antithrombin III-Independent Thrombin Inhibitors and Heparin on Fibrin Accretion onto Fibrin-Coated Polyethylene

1993 ◽  
Vol 69 (02) ◽  
pp. 130-134 ◽  
Author(s):  
F D Rubens ◽  
J I Weitz ◽  
J L Brash ◽  
R L Kinlough-Rathbone
Keyword(s):  
Vascular Graft ◽  
Antithrombin Iii ◽  
Vascular Grafts ◽  
Barium Chloride ◽  
Thrombin Inhibitors ◽  
Thrombin Inhibitor ◽  
Recombinant Hirudin ◽  
Graft Thrombosis ◽  
Polyethylene Tubing

SummaryProsthetic vascular grafts become coated with a layer of fibrin that contributes to graft thrombosis and occlusion. We compared the effect of antithrombin III-independent inhibitors of thrombin with heparin for their ability to prevent fibrin accretion onto a model of a vascular graft formed in vitro by coating polyethylene tubing with thrombin bound to a layer of polymerized fibrin. Equivalent antithrombin concentrations of heparin, D-Phe-Pro-Arg CH2Cl (PPACK), recombinant hirudin (r-hirudin), and Hirulog-1 were added to barium chloride-adsorbed plasma containing radiolabelled fibrinogen. Whereas, PPACK and r-hirudin persistently inhibited fibrin accretion, the inhibition by heparin was transient. Hirulog-1 had no effect on early fibrin accretion and was actually associated with enhanced accretion at 30 min (control 11.7 ± 2.0 μg fibrin/cm2; Hirulog-1, 18.4 ± 3.5 μg fibrin/cm2, p <0.001). Both Hirulog-1 and r-hirudin displaced radiolabelled thrombin from the fibrin surface. Whereas hirudin-thrombin complexes are stable, Hirulog-1 produces only transient inhibition of the displaced thrombin thereby accounting for the enhanced fibrin accretion with this anticoagulant. These studies show that the antithrombin III-independent inhibitors, r-hirudin and PPACK, are more effective inhibitors of fibrin accretion onto fibrin-coated polyethylene than heparin or Hirulog-1. In addition, they emphasize the importance of determining the ability of anticoagulants to displace thrombin from fibrin and to form stable thrombin-inhibitor complexes; lack of stability of thrombin-inhibitor complexes must be countered by levels of anticoagulant that are adequate to maintain its effectiveness.

The Effect of Thrombin Inhibitors on Tissue Plasminogen Activator Induced Thrombolysis in a Rat Model

1992 ◽  
Vol 68 (01) ◽  
pp. 064-068 ◽  
Author(s):  
Petr Klement ◽  
Anita Borm ◽  
Jack Hirsh ◽  
John Maraganore ◽  
Gregory Wilson ◽  
...  
Keyword(s):  
Blood Flow ◽  
Plasminogen Activator ◽  
Tissue Plasminogen Activator ◽  
Rat Model ◽  
Antithrombin Iii ◽  
Balloon Catheter ◽  
Thrombin Inhibitors ◽  
Thrombin Inhibitor ◽  
Limited Effectiveness ◽  
Tissue Plasminogen

SummarySuccessful coronary thrombolysis depends on rapidly restoring blood flow and maintaining patency of the infarct-related artery. Although widely used as an adjunct to lytic therapy, heparin is limited in its ability to produce these effects. Since the limitations of heparin may reflect its inability to inactivate clot-bound thrombin, we developed a rat model of tissue plasminogen activator (t-PA) induced thrombolysis to compare doses of heparin, hirudin, hirulog (a synthetic hirudin-derived peptide), and D-Phe-Pro-ArgCH2Cl (PPACK) that produced a 4-fold prolongation of the baseline activated partial thromboplastin time (APTT) with saline in terms of their ability to accelerate thrombolysis and to prevent reocclusion. A thrombus rich in red cells and fibrin was formed in the distal aorta by applying an external constrictor after denuding the endothelium with a balloon catheter. Thrombolysis was induced with t-PA (1 mg/kg bolus, followed by 1 mg kg–1 h–1 over 30 min) and the rats were then randomized to receive a concomitant 80 min infusion of a thrombin inhibitor or saline. By continuously monitoring blood flow and pre- and post-stenotic blood pressures, the time to clot lysis, and the number of reocclusions were determined. Compared to saline, heparin had no significant effect on these variables. In contrast, hirudin, hirulog, and PPACK significantly (p <0.01) increased the percentage of the time that the vessel remained patent from 63.9 ± 7.7 to 90.7 ± 2.2, 94.0 ± 0.9, and 94.7 ± 1.0%, respectively by significantly (p <0.01) decreasing the number of reocclusions. The superiority of the antithrombin III-independent inhibitors over heparin supports the hypothesis that the limited effectiveness of heparin in this setting reflects its inability to inactivate clot-bound thrombin. Compared to saline, hirulog and PPACK also significantly (p <0.02) accelerated the time to thrombolysis from 10.5 ± 2.3 to 4.4 ± 0.6, and 4.2 ± 0.8 min, respectively, whereas heparin and hirudin did not. The ability of the lower molecular weight inhibitors of thrombin to accelerate lysis may reflect their greater accessibility to clot-bound thrombin. These findings raise the possibility that the antithrombin III-independent inhibitors of thrombin may not be equally effective as adjuncts to thrombolytic therapy with t-PA.

scholarly journals Impact of ethanolic extract of Mikania glomerata on human breast cancer (MCF 7) cell line

2016 ◽  
Vol 2 (4) ◽  
pp. 94 ◽  
Author(s):  
Sarojini S. ◽  
Senthilkumaar P. ◽  
Ramesh V.
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Human Breast Cancer ◽  
Breast Cancer Cells ◽  
Ethanolic Extract ◽  
Breast Cancer Cell Lines ◽  
Human Breast ◽  
Anti Cancer ◽  
Mikania Glomerata ◽  
Mcf 7

The ethanol extract of Mikania glomerata has anti-proliferative effect on the human breast cancer cell lines. The object of the present work is to investigate the anti-cancer effect of Mikania glomerata ethanolic extract on breast cancer. Soxlet fractions using crude ethanolic extract of Mikania glomerata was prepared by standard extraction protocols. To check the antiproliferative effect of this extract, the extract chosen was tested for cell viability on the breast cancer cells MCF 7 in different concentrations. Cell viability was evaluated by MTT assay for 24 hour and 48 hours. The LD50 value was calculated and different morphometric assays were performed with the effective dose of the extract. The effect of the extract on the normal cell was evaluated as well. Cell proliferation, cell cycle, Clonogenic survival, Apoptosis and MTT assays were performed. The ethanolic extract showed a dose-dependent and time dependent inhibition on cell proliferation in the breast cancer cell lines. It showed low cytotoxicity in the normal cells and inhibited cellular adhesion and wound healing in treated cancer cells. The present study suggests that the leaf extract from Mikania glomerata induces anticancer effect on the breast cancer cells. Further study might help to confirm it as an anti-cancer drug.

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