Genes affected by Ret activation during estrogen stimulation or inhibition in MCF7/Aro cells
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE41405 | GEO | 2013/09/25
SECONDARY ACCESSION(S): PRJNA176962
REPOSITORIES: GEO
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Project description:Endocrine therapy is the main therapeutic option for patients with estrogen receptor alpha positive (ER+) breast cancer. Nevertheless, most of them become estrogen-independent and relapse after the treatment. Ret is a tyrosine kinase receptor that shows elevated expression levels in ER+ human breast tumors. In this study, we demonstrate that activation of the Ret receptor promotes proliferation as well as cell migration irrespective of endocrine therapy. Microarray data show that Ret activation involves changes in the expression of inflammatory- and motility-related genes. In vivo treatment with a Ret pathway inhibitor in a ER+/Ret+ mouse mammary cancer model, reduces tumor growth and lung metastasis even after endocrine therapy. Additionally, we show a connection between Ret and inflammatory pathways. The pro-inflamatory cytokine IL6 lies at the core of this regulation, which involves a positive feedback loop with IL6 and the Ret pathway reciprocally stimulating each other to further leading metastasis risk. Our findings provide insight into endocrine resistance mechanism and point at the Ret pathway as a potential target for future therapies. In order to model letrozole-sensitive breast cancer we use aromatase expressing MCF7 cells (MCF7/Aro). Six-day treatment (6 days) of cultures with letrozole (L) or fulvestrant (F) reversed the proliferative effects of the exposure to the estrogen (E2) precursor androstenedione (D4A). The addition of only EtOH (E) to the cells was used as control condition of deprivation. Treatment with the Ret ligand GDNF (G) partially rescues the inhibition of estrogen-dependent proliferation in these cells. To go deeper insight into the pathways involved, we decided to perform a microarray following different treatments (1-8: E, E+G, D, D+G, L, L+G, F, F+G) used in proliferation assays. Three biological replicates (rep 1-3) were used to the array.
2013-09-25 | E-GEOD-41405 | biostudies-arrayexpress
Project description:Understanding the complex molecular mechanisms underlying resistance to endocrine therapy is a major challenge in the treatment of estrogen receptor-positive (ER+) breast cancers. We have previously demonstrated that glial cell line-derived neurotrophic factor (GDNF) signaling via the receptor tyrosine kinase RET promotes estrogen independent activation of ER. Here we have addressed the relevance of GDNF-RET signaling in response to aromatase inhibitor treatment and explored the efficacy of using RET inhibitors in breast cancer models of aromatase inhibitor response and resistance. A GDNF-response gene set, identified from gene expression profiling, was demonstrated to be an independent prognostic marker of poor patient outcome and, importantly, to be predictive of poor response to aromatase inhibitor treatment and development of resistance. The relevance of these findings was validated first by demonstrating an association of RET protein expression in an independent cohort of aromatase inhibitor resistant patient samples. Second, in in vitro models, GDNF-mediated RET signaling was demonstrated to enhance the survival of aromatase inhibitor resistant cells and to increase resistance in aromatase inhibitor sensitive cells. These effects could be reversed by targeting GDNF/RET signaling with the RET selective inhibitor NVP-BBT594 thus identifying GDNF-RET signaling as a potential therapeutic target, particularly in breast cancers resistant to aromatase inhibitors.<br>MCF7 cells were E2-deprived by culturing in phenol red-free RPMI 1640 supplemented with 10% DCC for 3 days and then serum-starved overnight in the presence or absence of fulvestrant (ICI182,780) (100 nM). The following day, cells were treated with GDNF (20 ng/ml) for 0, 4, 8, 24 and 48 hours in the presence or absence of fulvestrant (ICI182,780) (100 nM).
2013-01-17 | E-MEXP-3662 | biostudies-arrayexpress
Project description:One of the greatest advances in therapy of estrogen receptor positive breast cancer has been the development of endocrine therapy. More than two thirds of primary breast tumors express estrogen receptor alpha (ERα) and their growth is mainly dependent on estrogen receptor activity. Several therapeutic approaches have thus been designed to inhibit ER activity in breast tissue. Tamoxifen, a selective ER modulator, is one of the main treatment options for premenopausal women with advanced ER positive breast cancer, and has also become well established as adjuvant therapy in the early breast cancer setting (Davies et al., 2011; Group, 1998; Jaiyesimi et al., 1995). In contrast to tamoxifen, which in other tissues such as bone and endometrium, can exert partial agonistic activity (Braithwaite et al., 2003; Fisher et al., 1994; Pietras, 2006), the selective ER downregulator, fulvestrant, is a potent ER antagonist. Binding of fulvestrant to ER inhibits receptor dimerization and nuclear uptake, prevents estrogen-response element binding and accelerates ER degradation (Dauvois et al., 1993; Dowsett et al., 2005; Fawell et al., 1990; Wakeling et al., 1991). Fulvestrant is approved for treatment of postmenopausal women with advanced breast cancer who have relapsed or progressed on first-line endocrine therapy (Howell et al., 2002; Osborne et al., 2002; Robertson et al., 2003). Estrogen deprivation by treatment with aromatase inhibitors (such as letrozole, anastrozole or exemestane) which block synthesis of estrogens is another effective therapy option in postmenopausal women (Bonneterre et al., 2000; Cuzick et al., 2010; Dowsett et al., 2010; Mouridsen et al., 2001; Nabholtz et al., 2000). The large majority of patients with ER+ breast cancer experience an initial response to endocrine therapy, however, in many of these patients, the disease subsequently progresses and eventually anti-estrogen therapy ceases to have effect. Biomarkers predicting response to estrogen deprivation and new alternative treatments targeting the pathways supporting estrogen independent growth are therefore urgently needed (Patani and Martin, 2014; Patani et al., 2013). In order to understand how tumors respond to withdrawal of their main growth signal, a comparison of molecular features of tumor before and during endocrine therapy is necessary, and the fate of individual cancer cell sub-clones should be monitored. Since studies of cellular dynamics are very difficult to perform with clinical material, we made use of a patient derived, estrogen dependent, orthotopically growing luminal-like primary breast cancer xenograft model (PDX) (Bergamaschi et al., 2009; Huuse et al., 2012). This PDX model is a representative model for luminal breast cancers as the molecular characteristics, cellular heterogeneity and estrogen dependency of the primary tumor are retained over many passages. Functionally different subpopulations of cancer cells were previously defined by expression of the markers CD24 and SSEA-4 in this model (Skrbo et al., 2014), and it is therefore a suitable model for comparison of cellular and molecular effects of estrogen deprivation and ER-signaling inhibition. In this study, a quantitative MS-based proteomic analysis using SILAC and a label-free approach were performed, aiming to map changes in protein expression induced by endocrine therapy. Inhibition of ER-signaling seemed to induce CD24 and SSEA-4 expression on residual tumor cells. Proteomic analysis revealed overexpression of enzymes involved in TCA cycle, oxidative phosphorylation and fatty acid beta-oxidation following endocrine treatment when compared to untreated tumors. These results indicated possible reprogramming of cell metabolism and utilization of aerobic respiration, i.e. oxidative phosphorylation, in response to endocrine therapy.
2022-02-28 | PXD002352 | Pride
Project description:Transcriptionally active ESR1 fusions promote endocrine therapy (ET)-resistant growth and metastasis of estrogen receptor-alpha positive (ERα+) breast cancer. Currently, there are no targeted treatment options for tumors harboring active fusions because the ESR1 ligand binding domain (LBD) has been replaced with non-drug binding sequences from the 3’ partner gene. A mass spectrometry (MS)-based Kinase Inhibitor Pulldown Assay (KIPA) demonstrated an increase of multiple receptor tyrosine kinases including RET in T47D cells expressing active ESR1 fusions. Integrated proteogenomics defined tumor subsets that could be responsive to RET and CDK4/6 directed therapy from 22 biologically heterogeneous ERα+ patient-derived xenograft (PDX) tumors. Inhibition of RET by repurposing an FDA-approved drug significantly suppressed ESR1 fusion-driven growth of cell, PDX-derived organoid (PDXO) and PDX models. CDK4/6 inhibitor treatment showed similar tumor reductions to RET inhibition. Here, we reveal therapeutic kinase vulnerabilities in ESR1 fusion-driven tumors, which will lay the framework for future clinical trials.
2023-10-24 | PXD033339 | Pride
Project description:Activation of the PI3K pathway in estrogen receptor α (ER)-positive (+) breast cancer is associated with reduced ER expression and activity, luminal B subtype, and poor outcome. PTEN is a negative regulator of the PI3K pathway typically lost in ER-negative (-) breast cancer. To clarify the effect of PTEN down-regulation on the response of ER+/HER2- breast cancer to endocrine therapy, we established reduced PTEN cell models using inducible knockdown. We found that only moderate PTEN reduction is sufficient to enhance PI3K signaling, generate a gene signature associated with luminal B subtype, and cause endocrine resistance. Combining endocrine therapy with mTOR, AKT, or MEK inhibitors improves antitumor activity, but the efficacy varies by type of endocrine therapy and the specific inhibitor. Fulvestrant plus an AKT inhibitor is the most potent combination when PTEN is reduced, inducing apoptosis and tumor regression. This combination deserves further study in patients with PI3K pathway activation.
2014-06-30 | GSE53300 | GEO
Project description:Oral selective estrogen receptor degraders (SERDs) could become the backbone endocrine therapy (ET) for estrogen receptor-positive (ER+) breast cancer, as they achieve greater inhibition of ER-driven cancers than current ETs and overcome key resistance mechanisms. This dataset was aimed at exploring the preclinical effects of the next-generation oral SERD camizestrant (AZD9833) on 7 PDX models. Mice were treated with fulvestrant or camizestrant for 4, 24, 48, 72 hours, with at least four replicates per condition.
2023-09-11 | E-MTAB-13139 | biostudies-arrayexpress
Project description:<p>The genomic evolution of breast cancers exposed to systemic therapy and its effects on clinical outcome have not been broadly characterized. We integrated the genomic sequencing of 1918 breast cancers, including 1501 hormone receptor-positive tumors, with detailed clinical information and treatment outcomes. Functional mutations in ERBB2 and loss-of-function mutations in NF1 were more than twice as common in post-endocrine therapy tumors compared to treatment-naive tumors. Additional alterations in the MAPK pathway (EGFR, KRAS among others) and in estrogen receptor transcriptional regulators (MYC, CTCF, FOXA1 and TBX3) were also more common compared to hormonal therapy-naive tumors.</p> <p>To determine whether candidate genomic lesions in the MAPK pathway and estrogen receptor transcriptional regulators were present prior to therapy or whether such lesions arose under the selective pressure of therapy, we performed whole-exome sequencing in select patients who had adequate samples acquired prior to and after progression on endocrine therapy. In total, 95 specimens corresponding to 30 treatment-naive primary tumors, 35 post-treatment tumors, and 30 normal samples were sequenced from 30 patients with endocrine-resistant metastatic breast cancer.</p>
| phs001674 | dbGaP
Project description:Oral selective estrogen receptor degraders (SERDs) could become the backbone endocrine therapy (ET) for estrogen receptor-positive (ER+) breast cancer, as they achieve greater inhibition of ER-driven cancers than current ETs and overcome key resistance mechanisms. This dataset was aimed at exploring the preclinical effects of the next-generation oral SERD camizestrant (AZD9833) on MCF7 and CAMA1 cell lines. Cells were treated with 1 nM estradiol and 100 nM fulvestrant, AZD9496, or camizestrant for 24 hours, with three replicates per condition and non-estradiol-treated controls.
2023-09-11 | E-MTAB-13113 | biostudies-arrayexpress
Project description:The molecular mechanisms of endocrine resistance in breast cancer remain poorly understood. Here we used PRO-seq to map the location of hundreds of genes and thousands of distal enhancers whose activities differ between endocrine sensitive and resistant MCF-7 cells. Our genome-wide screen identified a 16-fold transcriptional increase in glial-cell line derived neurotrophic factor (GDNF), a RET tyrosine kinase receptor ligand, which is both necessary and sufficient for resistance in MCF-7 cells. GDNF causes endocrine resistance by switching the active state of a bi-stable feedback loop from ERα signaling to GDNF-RET signaling. To catalyze this switch, we found that GDNF directly downregulates ERα transcription and activates the transcription factor EGR1, which, in turn, induces GDNF expression. Remarkably, both MCF-7 cells and ER+ primary tumors appear poised for endocrine resistance via the RET signaling pathway, but lack robust RET ligand expression and only develop resistance upon expression of GDNF or other RET ligands.
2018-02-22 | GSE93229 | GEO
Project description:Around two thirds of breast tumors are characterized by the expression of estrogen receptor α and are therapeutically treated by blocking estrogen signaling. First line endocrine therapeutics are Tamoxifen which displaces estrogen form its receptor preventing receptor activation and aromatase inhibitors which prevent the formation of estrogen and thereby hormone-deprive the tumors. Therapy resistance remains a major clinical problem, especially for patients with late-stage diagnoses. Tumor heterogeneity may promote therapy resistance either through the selection of pre-existing rare clones or by providing a repertoire of cells that may develop resistance over time. In order to study endocrine therapy resistance on a clonal level, we have developed barcoded (allowing the tracking of single cells) endocrine therapy sensitive and resistant breast cancer cell lines. From these complex cell pools, multiple single cells characterized by a specific barcode were isolated and grown out. We then subjected the clones to phosphoproteomics measurement by Mass spectrometry. Based on their phosphorylation pattern, the kinase activity profiles of endocrine therapy resistant clones were determined to identify differentially activated kinases with implications in therapy resistance.
2024-01-26 | PXD040478 | Pride