scholarly journals The Effect of Canertinib on Sensitivity of Cytotoxic Drugs in Tamoxifen-Resistant Breast Cancer Cells In Vitro

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Hesham A. M. Gomaa ◽  
Asmaa T. Ali ◽  
M. Abdel Gabbar ◽  
M. A. Kandeil
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Breast Cancer Cells ◽  
Kinase Inhibitor ◽  
Apoptotic Cell ◽  
Combined Treatment ◽  
Single Agent ◽  
Tamoxifen Resistance ◽  
Cytotoxic Drugs ◽  
Mcf 7

Aims and Objectives. To investigate and examine the reversal effects of canertinib on the activity of EGFR and tamoxifen resistance in drug-resistant human breast carcinoma cells (MCF-7/TamR). Materials and Methods. The antiproliferative activity of canertinib alone or in combination with a conventional EGFR-targeting chemotherapies cytotoxic drugs differing in the mechanism(s) of action, such as paclitaxel, carboplatin, etoposide, vinorelbine, and daunorubicin as well as resistance mechanisms of EGFR targeting, have been investigated. Results. With an elevated dosage of canertinib, a significant decrease in proliferation and increase in apoptosis was observed. The treatment with higher doses of canertinib resulted in a 2-3-fold increase in apoptosis. In the combined treatment, it had been noticed a significant developed apoptotic cell death rather induced by single agent treatment. A significant downregulation of the antiapoptotic protein bcl-2 was exposed by immunocytochemistry investigation. Sensitivity to paclitaxel was also measured and was found to inversely correlate to bcl-2 status. Conclusion. Proliferation inhibition and apoptosis in MCF-7/TAM-R cells increase with increasing dosage of canertinib. This suggests that canertinib can reverse tamoxifen resistance in breast cancer cells. The antitumor effect of this EGFR-irreversible tyrosine kinase inhibitor provides a rationale for its clinical evaluation in combination with other cytotoxic drugs.

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 Mechanisms of Gefitinib-mediated reversal of tamoxifen resistance in MCF-7 breast cancer cells by inducing ERα re-expression

2015 ◽  
Vol 5 (1) ◽  
Author(s):  
Xia Zhang ◽  
Bin Zhang ◽  
Jie Liu ◽  
Jiwei Liu ◽  
Changzheng Li ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Breast Cancer Cells ◽  
Tamoxifen Resistance ◽  
Mcf 7

scholarly journals Proton pump inhibitors enhance chemosensitivity, promote apoptosis, and suppress migration of breast cancer cells

2020 ◽  
Vol 70 (2) ◽  
pp. 179-190 ◽  
Author(s):  
Worood G. Ihraiz ◽  
Mamoun Ahram ◽  
Sanaa K. Bardaweel
Keyword(s):  
Breast Cancer ◽  
Cell Migration ◽  
Synergistic Effect ◽  
Cancer Cells ◽  
Cell Lines ◽  
Proton Pump ◽  
Breast Cancer Cells ◽  
Combined Treatment ◽  
Combined Effects ◽  
Mcf 7

AbstractBreast cancer is the most common cancer and is the leading cause of cancer deaths among women worldwide. Despite the availability of numerous therapeutics for breast cancer management, cytotoxicity and emergence of drug resistance are major challenges that limit their benefits. The acidic microenvironment surrounding tumor cells is a common feature inducing cancer cell invasiveness and chemoresistance. Proton pump inhibitors (PPIs) are one of the most commonly prescribed drugs for the treatment of acid-related conditions. PPIs have been reported to exhibit antitumorigenic effects in many cancer types. In this study, the anti-proliferative and anti-migratory effects of PPIs in three breast cancer cell lines; MCF-7, T47D, and MDA-MB-231 cells, have been investigated. In addition, the combined effects of PPIs with anticancer drugs, as well as the mechanism of PPI-mediated anti-proliferative activity were evaluated. The anti-proliferative and combined effects of PPIs were evaluated by MTT assay. Cell migration was assessed using the wound-healing assay. The mechanism of cell death was assessed using annexin V-FITC/propidium iodide staining flow cytometry method. Our results indicated that PPIs treatment significantly inhibited the growth of breast cancer cells in a dose-dependent manner. The antiproliferative activity of PPIs was significantly induced by apoptosis in all tested cell lines. The combined treatment of PPIs with doxorubicin resulted in a synergistic effect in all cell lines, whereas the combined treatment with raloxifene exhibited synergistic effect in T47D cells only and additive effects in MDA-MB-231 and MCF-7 cells. In addition, PPIs treatment significantly reduced cell migration in MDA-MB-231 cells. In conclusion, the addition of PPIs to the treatment regimen of breast cancer appears to be a promising strategy to potentiate the efficacy of chemotherapy and may suppress cancer metastasis.

scholarly journals Signal Transducer and Activator of Transcription 5b, c-Src, and Epidermal Growth Factor Receptor Signaling Play Integral Roles in Estrogen-Stimulated Proliferation of Estrogen Receptor-Positive Breast Cancer Cells

2008 ◽  
Vol 22 (8) ◽  
pp. 1781-1796 ◽  
Author(s):  
Emily M. Fox ◽  
Teresa M. Bernaciak ◽  
Jie Wen ◽  
Amanda M. Weaver ◽  
Margaret A. Shupnik ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cyclin D1 ◽  
Cancer Cells ◽  
Breast Cancer Cells ◽  
Transcriptional Activity ◽  
Growth Factor Receptor ◽  
Tamoxifen Resistance ◽  
Cancer Proliferation ◽  
Epidermal Growth ◽  
Mcf 7

Abstract 17β-Estradiol (E2) acts through the estrogen receptor α (ERα) to stimulate breast cancer proliferation. Here, we investigated the functional relationship between ERα and signal transducer and activator of transcription (STAT)5b activity in ER+ MCF-7 and T47D human breast cancer cells after specific knockdown of STAT5b. STAT5b small interfering RNA (siRNA) inhibited E2-induced bromodeoxyuridine (BrdU) incorporation in both cell lines, as well as the E2-induced increase in MCF-7 cell number, cyclin D1 and c-myc mRNA, and cyclin D1 protein expression, indicating that STAT5b is required for E2-stimulated breast cancer proliferation. E2 treatment stimulated STAT5b tyrosine phosphorylation at the activating tyrosine Y699, resulting in increased STAT5-mediated transcriptional activity, which was inhibited by a Y669F STAT5b mutant. E2-induced STAT5-mediated transcriptional activity was inhibited by overexpressing a kinase-defective epidermal growth factor receptor (EGFR), or the EGFR tyrosine kinase inhibitor tyrphostin AG1478, indicating a requirement for EGFR kinase activity. Both E2-induced STAT5b tyrosine phosphorylation and STAT5-mediated transcription were also inhibited by the ER antagonist ICI 182,780 and the c-Src inhibitor PP2, indicating additional requirements for the ER and c-Src kinase activity. EGFR and c-Src kinase activities were also required for E2-induced cyclin D1 and c-myc mRNA. Together, these studies demonstrate positive cross talk between ER, c-Src, EGFR, and STAT5b in ER+ breast cancer cells. Increased EGFR and c-Src signaling is associated with tamoxifen resistance in ER+ breast cancer cells. Here we show that constitutively active STAT5b not only increased basal DNA synthesis, but also conferred tamoxifen resistance. Because STAT5b plays an integral role in E2-stimulated proliferation and tamoxifen resistance, it may be an effective therapeutic target in ER+ breast tumors.

scholarly journals Cyclooxygenase-2 utilizes Jun N-terminal kinases to induce invasion, but not tamoxifen resistance, in MCF-7 breast cancer cells

2013 ◽  
Vol 30 (3) ◽  
pp. 1506-1510 ◽  
Author(s):  
VIANEY GONZALEZ-VILLASANA ◽  
YOLANDA GUTIÉRREZ-PUENTE ◽  
ANA M. TARI
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Breast Cancer Cells ◽  
Tamoxifen Resistance ◽  
Cyclooxygenase 2 ◽  
Mcf 7
Sign in / Sign up

Export Citation Format

Share Document