scholarly journals Cyclin E expression is associated with high levels of replication stress in triple-negative breast cancer

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Sergi Guerrero Llobet ◽  
Bert van der Vegt ◽  
Evelien Jongeneel ◽  
Rico D. Bense ◽  
Mieke C. Zwager ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Dna Replication ◽  
Cancer Cells ◽  
Triple Negative ◽  
Cyclin E ◽  
Replication Stress ◽  
Clinical Samples ◽  
Breast Cancers ◽  
Spearman Correlation ◽  
Expression Levels

Abstract Replication stress entails the improper progression of DNA replication. In cancer cells, including breast cancer cells, an important cause of replication stress is oncogene activation. Importantly, tumors with high levels of replication stress may have different clinical behavior, and high levels of replication stress appear to be a vulnerability of cancer cells, which may be therapeutically targeted by novel molecularly targeted agents. Unfortunately, data on replication stress is largely based on experimental models. Further investigation of replication stress in clinical samples is required to optimally implement novel therapeutics. To uncover the relation between oncogene expression, replication stress, and clinical features of breast cancer subgroups, we immunohistochemically analyzed the expression of a panel of oncogenes (Cyclin E, c-Myc, and Cdc25A,) and markers of replication stress (phospho-Ser33-RPA32 and γ-H2AX) in breast tumor tissues prior to treatment (n = 384). Triple-negative breast cancers (TNBCs) exhibited the highest levels of phospho-Ser33-RPA32 (P < 0.001 for all tests) and γ-H2AX (P < 0.05 for all tests). Moreover, expression levels of Cyclin E (P < 0.001 for all tests) and c-Myc (P < 0.001 for all tests) were highest in TNBCs. Expression of Cyclin E positively correlated with phospho-RPA32 (Spearman correlation r = 0.37, P < 0.001) and γ-H2AX (Spearman correlation r = 0.63, P < 0.001). Combined, these data indicate that, among breast cancers, replication stress is predominantly observed in TNBCs, and is associated with expression levels of Cyclin E. These results indicate that Cyclin E overexpression may be used as a biomarker for patient selection in the clinical evaluation of drugs that target the DNA replication stress response.

scholarly journals Cyclin E expression is associated with high levels of replication stress in triple-negative breast cancer

2019 ◽  
Author(s):  
Sergi Guerrero Llobet ◽  
Bert van der Vegt ◽  
Evelien Jongeneel ◽  
Rico D. Bense ◽  
Carolien P. Schröder ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Dna Replication ◽  
Cancer Cells ◽  
Triple Negative ◽  
Cyclin E ◽  
Replication Stress ◽  
Experimental Models ◽  
Clinical Samples ◽  
Spearman Correlation ◽  
Expression Levels

AbstractReplication stress entails the improper progression of DNA replication. In cancer cells, including breast cancer cells, an important cause of replication stress is oncogene activation. Importantly, tumors with high levels of replication stress may have different clinical behavior, and high levels of replication stress appear to be a vulnerability of cancer cells, which may be therapeutically targeted by novel molecularly targeted agents. Unfortunately, data on replication stress is largely based on experimental models. Further investigation of replication stress in clinical samples is required to optimally implement novel therapeutics. To uncover the relation between oncogene expression, replication stress and clinical features of breast cancer subtypes, we immunohistochemically analyzed the expression of a panel of oncogenes (Cdc25a, Cyclin E and c-Myc) and markers of replication stress (phospho-Ser33-RPA32 and γ-H2AX) in treatment-naive breast tumor tissues (n=384). Triple-negative breast cancers (TNBCs) exhibited the highest levels of phospho-Ser33-RPA32 (P<0.001 for all tests) and γ-H2AX (P<0.05 for all tests). Moreover, expression levels of Cyclin E (P<0.001 for all tests) and c-Myc (P<0.001 for all tests) were highest in TNBCs. Expression of Cyclin E positively correlated with phospho-RPA32 (Spearman correlation r=0.37, P<0.001) and γ-H2AX (Spearman correlation r=0.63, P<0.001). Combined, these data indicate that replication stress is predominantly observed in TNBCs, and is associated with expression levels of Cyclin E. These results indicate that Cyclin E overexpression may be used as a biomarker for patient selection in the clinical evaluation of drugs that target the DNA replication stress response.

scholarly journals Use of Proton Pump Inhibitors as Adjunct Treatment for Triple-Negative Breast Cancers. An Introductory Study

2014 ◽  
Vol 17 (3) ◽  
pp. 439 ◽  
Author(s):  
Wayne Goh ◽  
Inna Sleptsova-Freidrich ◽  
Nenad Petrovic
Keyword(s):  
Breast Cancer ◽  
Cancer Treatment ◽  
Cancer Cells ◽  
Proton Pump ◽  
Triple Negative Breast Cancer ◽  
Triple Negative ◽  
Dependent Manner ◽  
Breast Cancers ◽  
Gastric Type ◽  
Dose Dependent

PURPOSE: Triple negative breast cancers (estrogen, progesterone and human epidermal growth factor 2 (HER2) receptor-negative) are among the most aggressive forms of cancers with limited treatment options. Doxorubicin is one of the agents found in many of the current cancer treatment protocols, although its use is limited by dose-dependent cardiotoxicity. This work investigates one of the ways to suppress cancer growth by inhibiting tumor cell ability to remove acid accumulated during its metabolism by proton pump inhibitor esomeprazole (a drug with extensive clinical use) which could serve as an addition to doxorubicin therapy. METHODS: In this work, we have investigated growth suppression of triple-negative breast cancer cells MDA-MB-468 by esomeprazole and doxorubicin by trypan blue exclusion assay. Measurement of acidification of treated cancer cells was performed using intracellular pH-sensitive probe, BCECF-AM. Finally, expression of gastric type proton pump (H+/K+ ATPase, a target for esomeprazole) on MDA-MB-468 cells was detected by immunofluorescence and Western blotting. RESULTS: We have found that esomeprazole suppresses growth of triple-negative breast cancer cell in vitro in a dose-dependent manner through increase in their intracellular acidification. In contrast, esomeprazole did not have significant effect on non-cancerous breast epithelial MCF-10A cells. Esomeprazole increases doxorubicin effects suggesting that dual treatments might be possible. In addition, response of MDA-MB-468 cells to esomeprazole could be mediated by gastric type proton pump (H+/K+ ATPase) in cancer cells contrary to previous beliefs that this proton pump expression is restricted to parietal cells of the stomach epithelia. CONCLUSION: This study provides first evidence that adjunct use of esomeprazole in breast cancer treatment might be a possible to combat adverse effects of doxorubicin and increase its effectiveness. This article is open to POST-PUBLICATION REVIEW. Registered readers (see “For Readers”) may comment by clicking on ABSTRACT on the issue’s contents page.

scholarly journals HMGA1 Modulates Gene Transcription Sustaining a Tumor Signalling Pathway Acting on the Epigenetic Status of Triple-Negative Breast Cancer Cells

Cancers ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 1105 ◽  
Author(s):  
Penzo ◽  
Arnoldo ◽  
Pegoraro ◽  
Petrosino ◽  
Ros ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Triple Negative Breast Cancer ◽  
Transcriptional Activation ◽  
Triple Negative ◽  
Critical Factor ◽  
Regulatory Sequences ◽  
Breast Cancers ◽  
Creb Binding Protein ◽  
Mesenchymal Transition

Chromatin accessibility plays a critical factor in regulating gene expression in cancer cells. Several factors, including the High Mobility Group A (HMGA) family members, are known to participate directly in chromatin relaxation and transcriptional activation. The HMGA1 oncogene encodes an architectural chromatin transcription factor that alters DNA structure and interacts with transcription factors favouring their landing onto transcription regulatory sequences. Here, we provide evidence of an additional mechanism exploited by HMGA1 to modulate transcription. We demonstrate that, in a triple-negative breast cancer cellular model, HMGA1 sustains the action of epigenetic modifiers and in particular it positively influences both histone H3S10 phosphorylation by ribosomal protein S6 kinase alpha-3 (RSK2) and histone H2BK5 acetylation by CREB-binding protein (CBP). HMGA1, RSK2, and CBP control the expression of a set of genes involved in tumor progression and epithelial to mesenchymal transition. These results suggest that HMGA1 has an effect on the epigenetic status of cancer cells and that it could be exploited as a responsiveness predictor for epigenetic therapies in triple-negative breast cancers.

Using epigenetic reprogramming to target triple-negative breast cancer

2009 ◽  
Vol 27 (15_suppl) ◽  
pp. e14565-e14565
Author(s):  
D. Sharma ◽  
B. B. Knight ◽  
R. Yacoub ◽  
T. Liu ◽  
L. Taliaferro-Smith ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Breast Cancer Cells ◽  
Hormone Receptors ◽  
Triple Negative ◽  
Combined Treatment ◽  
Brdu Incorporation ◽  
Breast Cancers

e14565 Background: The outcome for patients with breast cancer has been significantly improved by the use of targeted agents. The prognosis of triple negative (TN) breast cancers, which do not express hormone receptors (ER, PR) or Her2, is poor, because of an aggressive clinical course and lack of targeted therapeutic agents. Epigenetic silencing of specific genes has been observed in breast cancer and some of these genes are more important due to available targeted therapies such as ER. Since all endocrine therapies are designed to block ER function in some way, the identification of new therapies or strategies that could sensitize TN breast cancers to existing endocrine therapy could provide a revolutionary means of treating this aggressive subtype of cancer Methods: We examined the efficacy of combined treatment of HDAC inhibitor LBH589 and DNMT inhibitor decitabine to regenerate ER and PR in TN breast cancer cells using RT-PCR and immunoblotting. Changes in growth and proliferation of TN breast cancer cells in response to LBH589 and decitabine treatment were determined by XTT, BrdU incorporation and colony formation assay. Changes in apoptotic proteins were determined by western blotting. Athymic nude mice were used to establish pre-clinical models for TN breast cancer cells and effectiveness of combined treatment of LBH589 and decitabine was determined. Tumors biopsies were analyzed for ER and PR re-expression by western blot analysis and immunohistochemistry at the end of the treatment. Results: Combined treatment of LBH589 and decitabine resulted in re-expression of ER and PR in TN breast cancers in vitro and in vivo. Although re-expression of ER and PR were noted following LBH589 treatment alone, re-expression was more robust with the combination. TN breast cancer cells showing re-expressed ER can be targeted with tamoxifen. Tamoxifen inhibits growth of TN breast cancer cells re- expressing ER by triggering apoptosis. Conclusions: The importance of epigenetic events such as DNA methylation and HDAC inhibition in tumor progression is becoming increasingly evident. A trial evaluating the ability of LBH589 and decitabine to re- express ER, which can then be targeted by tamoxifen, is planned in patients with metastatic TN breast cancer. No significant financial relationships to disclose.

Biopsy-driven study to identify biomarkers of drug resistance in patients with triple-negative breast cancer.

2012 ◽  
Vol 30 (30_suppl) ◽  
pp. 87-87
Author(s):  
Adriana Aguilar-Mahecha ◽  
Josiane Lafleur ◽  
Elaheh Ahmadzadeh ◽  
Ewa Przybytkowski ◽  
Carole Seguin ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Drug Resistance ◽  
Cell Lines ◽  
Triple Negative ◽  
Acquired Resistance ◽  
Great Difficulty ◽  
Clinical Samples ◽  
Drug Resistant ◽  
Breast Cancers ◽  
Breast Cancer Patients

87 Background: Resistance to chemotherapy is the underlying cause of death in most patients dying of breast cancer. Patients with early stages of breast cancer whose tumor is or becomes resistant to chemotherapy have a poor prognosis, while women with advanced breast cancer live as long as their tumors respond to chemotherapy. Because of the great difficulty of obtaining clinical samples from drug resistant tumors in patients, there is scant information about molecular factors from actual drug resistant tumors. This project aims to systematically profile resistant triple negative breast cancers (TNBCs) in order to discover molecular “resistance” genes/proteins as a first step to develop strategies to overcome drug resistance. Methods: Paired biopsies are collected from TNBC patients (NCT01276899). Four needle core biopsies are collected before the initiation of treatment and 2 weeks before surgery or at the time of progression in the neoadjuvant and metastatic settings respectively. Paired biopsies will undergo Next Gen Sequencing, flow sorted aCGH analysis, gene expression and miRNA profiling as well as phosphoproteomic profiling using reverse phase protein arrays. Results: We have currently enrolled 28 patients in the neoadjuvant setting and 3 metastatic patients. We have standardized the methods of collection and processing of tissue and blood specimens to ensure their molecular integrity and compatibility with different genomic and proteomic molecular platforms. Analysis of tumor cellularity has been incorporated into our quality control and we have optimized the extraction of nucleic acids to obtain high yields and optimal quality. In parallel, we have generated acquired resistance to paclitaxel in a panel of TNBC cell lines. These cell lines will also undergo genomic profiling and exome sequencing to identify molecular markers of resistance that will be correlated with the markers found in patient samples. Conclusions: This project will allow us to identify the molecular factors responsible for drug resistance in TNBCs and enable the elaboration of strategies to overcome resistance.

91 4E-BP1 expression levels determine sensitivity of triple negative breast cancer cells to mTOR inhibitors

2014 ◽  
Vol 50 ◽  
pp. 34
Author(s):  
K. Jastrzebski ◽  
B. Thijssen ◽  
J. Vidal Rodriguez ◽  
K. de Lint ◽  
C. Lieftink ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Triple Negative Breast Cancer ◽  
Breast Cancer Cells ◽  
Triple Negative ◽  
Mtor Inhibitors ◽  
Expression Levels

scholarly journals Eugenol-Induced Autophagy and Apoptosis in Breast Cancer Cells via PI3K/AKT/FOXO3a Pathway Inhibition

2021 ◽  
Vol 22 (17) ◽  
pp. 9243
Author(s):  
Mashan L. Abdullah ◽  
Othman Al-Shabanah ◽  
Zeinab K. Hassan ◽  
Mohamed M. Hafez
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Triple Negative ◽  
Kinase Inhibitor ◽  
Cyclin Dependent Kinase ◽  
Her2 Positive ◽  
Expression Levels ◽  
Cyclin Dependent Kinase Inhibitor ◽  
Gene And Protein Expression ◽  
Anti Cancer

The use of natural compounds is promising in approaches to prevent and treat cancer. The long-term application of most currently employed chemotherapy techniques has toxic side effects. Eugenol, a phenolic phytochemical extracted from certain essential oils, has an anti-cancer effect. The modulation of autophagy can promote either the survival or apoptosis of cancer cells. Triple-negative (MDA-MB-231) and HER2 positive (SK-BR-3) breast cancer cell lines were treated with different doses of eugenol. Apoptosis was detected by a flow-cytometry technique, while autophagy was detected by acridine orange. Real-time PCR and Western blot assays were applied to investigate the effect of eugenol on the gene and protein expression levels of autophagy and apoptotic genes. Treating cells with different concentrations of eugenol significantly inhibited cell proliferation. The protein levels of AKT serine/threonine kinase 1 (AKT), forkhead box O3 (FOXO3a), cyclin dependent kinase inhibitor 1A (p21), cyclin-dependent kinase inhibitor (p27), and Caspase-3 and -9 increased significantly in Eugenol-treated cells. Eugenol also induced autophagy by upregulating the expression levels of microtubule-associated protein 1 light chain 3 (LC3) and downregulating the expression of nucleoporin 62 (NU p62). Eugenol is a promising natural anti-cancer agent against triple-negative and HER2-positive breast cancer. It appears to work by targeting the caspase pathway and by inducing autophagic cell death.

Effect of mTOR inhibition on sensitivity of triple-negative breast cancer cells to epidermal growth factor inhibition

2009 ◽  
Vol 27 (15_suppl) ◽  
pp. 1055-1055 ◽  
Author(s):  
T. Liu ◽  
R. Yacoub ◽  
T. Graham ◽  
L. Yang ◽  
M. Tighiouart ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Metastatic Breast Cancer ◽  
Cancer Cells ◽  
Breast Cancer Cells ◽  
Triple Negative ◽  
Metastatic Breast ◽  
Mtor Inhibitors ◽  
Egfr Inhibitors ◽  
Breast Cancers ◽  
Mtor Inhibition

1055 Background: The outcome for patients with triple negative (TN) cancers is poor at least in part because of a lack of targeted therapies. Although 50% of TN breast cancers over-express EGFR, the use of EGFR inhibitors as single agents in patients with unselected and TN metastatic breast cancers has produced disappointing results. Likewise, mTOR inhibitors have modest activity as single agents in metastatic breast cancer. mTOR inhibitors have been demonstrated to activate the Akt pathway by a possible feedback mechanism, which could potentially sensitize TN breast cancer cells to upstream inhibitors. We have previously demonstrated that EGFR inhibitors in combination with rapamycin (RAPA) decrease cell survival, increase apoptosis, and are synergistic in TN breast cancer cells, compared to any of the agents alone (AACR 2008). We, therefore, evaluated the combination of mTOR and EGFR inhibition in vivo. Methods: Athymic mice were inoculated with TN (MDA-MB-231) breast cancer cells. One week after cell inoculation, mice were treated with vehicle, lapatinib 75mg/kg by mouth daily, RAPA 3mg/kg IP biweekly, or the combination. After 4 weeks of treatment, mice were sacrificed and tumors were assessed for target proteins by Western blotting and immunohistochemistry Results: The combination of RAPA and lapatinib resulted in a significant decrease in TN breast tumor volume (76 mm3), compared to rapamycin alone (133 mm3, p = 0.01), lapatinib alone (183 mm3, p < 0.0001) or control (188 mm3, p = 0.005). Neither lapatinib nor RAPA alone inhibited tumor growth significantly compared to control (p > 0.05). Interestingly, in contrast to our findings in vitro, the increase in pAkt noted in RAPA treated tumors was not decreased by lapatinib, despite the significant decrease in tumor size in tumors treated with the combination. Conclusions: These studies demonstrate that the combination of mTOR inhibition and lapatinib significantly inhibit TN breast cancer growth, compared with either agent alone. Given the lack of targeted therapies in TN breast cancers, these data support the possibility that mTOR inhibition can sensitize TN breast cancers to EGFR inhibitors. A clinical trial evaluating the combination of lapatinib and RAD001 as second-line therapy for TN metastatic breast cancer is planned. [Table: see text]

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