ETRepi
Ontology highlight
ABSTRACT:
PROVIDER: PRJEB11448 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| ERR1079180_1.fastq.gz | Fastqsanger.gz | |||
| ERR1079180_2.fastq.gz | Fastqsanger.gz | |||
| ERR1079181_1.fastq.gz | Fastqsanger.gz | |||
| ERR1079181_2.fastq.gz | Fastqsanger.gz | |||
| ERR1079182_1.fastq.gz | Fastqsanger.gz |
Items per page: 5 1 - 5 of 24 |
Similar Datasets
Project description:The estrogen receptor alpha (ERa) drives the growth of two-thirds of all breast cancers. Endocrine therapy impinges on estrogen-induced ERa activation to block tumor growth. However, half of ERa-positive breast cancers are tolerant or acquire endocrine therapy resistance. Here we demonstrate that breast cancer cells undergo genome-wide reprogramming of their chromatin landscape, defined by epigenomic maps and chromatin openness, as they acquire resistance to endocrine therapy. This reveals a role for the Notch pathway while excluding classical ERa signaling. In agreement, blocking Notch signaling, using gamma-secretase inhibitors, or targeting its downstream gene PBX1 abrogates growth of endocrine therapy-resistant breast cancer cells. Moreover Notch signaling through PBX1 directs a transcriptional program predictive of tumor outcome and endocrine therapy response. Comparing histone modifications (H3K4me2 and H3K36me3), chromatin openness (FAIRE) and PBX1 binding between endocrine therapy sensitive MCF7 and resistant MCF7-LTED cells.
2013-05-01 | E-GEOD-37323 | biostudies-arrayexpress
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
Project description:Estrogen Receptor alpha (ERα) is a ligand-inducible transcription factor that mediates estrogen signaling in hormone-responsive breast cancer (BC) and is the primary target of specific anticancer therapies. Although ERα blockade with these drugs is effective, the development of a resistance to treatment represents the key problem in clinical management of patients affected by this disease. Understanding the molecular mechanisms underlying ERα action in BC cells may help the identification of new therapeutic targets for more effective pharmacological treatment of endocrine therapy-resistant tumors. We recently discovered the epigenetic enzyme DOT1L (DOT1 Like Histone Lysine Methyltransferase) as a novel nuclear partner of ERα in BC cells. To investigate the involvement of DOT1L in mediating ERα actions in hormone-responsive and endocrine-resistant BC, physical and functional interaction between these two molecules on chromatin was mapped by Chromatin Immunoprecipitation coupled to Mass Spectrometry (ChIP-MS).
2019-02-09 | PXD010314 | Pride
Project description:Comprehensive profiling of hormone-dependent breast cancer (HDBC) has identified hundreds of protein-coding alterations contributing to cancer initiation, but only a handful have been linked to endocrine therapy resistance, potentially contributing to 40% of relapses. If other mechanisms underlie the evolution of HDBC under adjuvant therapy is currently unknown. In this work, we employ integrative functional genomics to dissect the contribution of cis-regulatory elements (CREs) to cancer evolution by focusing on 12 megabases of non-coding DNA, including clonal enhancers, gene promoters, and boundaries of topologically associating domains. Massive parallel epigenetic perturbation (CRISPRi) in vitro reveals context-dependent roles for many of these CREs, with a specific impact on dormancy entrance and endocrine therapy resistance. Profiling of CRE somatic alterations in a unique, longitudinal cohort of patients treated with endocrine therapies identifies non-coding changes potentially involved in therapy resistance. Overall, our data uncover how endocrine therapies triggers the emergence of transient features which could ultimately be exploited to hinder the adaptive process.
2024-06-27 | GSE197504 | GEO
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:The estrogen receptor alpha (ERa) drives the growth of two-thirds of all breast cancers. Endocrine therapy impinges on estrogen-induced ERa activation to block tumor growth. However, half of ERa-positive breast cancers are tolerant or acquire endocrine therapy resistance. Here we demonstrate that breast cancer cells undergo genome-wide reprogramming of their chromatin landscape, defined by epigenomic maps and chromatin openness, as they acquire resistance to endocrine therapy. This reveals a role for the Notch pathway while excluding classical ERa signaling. In agreement, blocking Notch signaling, using gamma-secretase inhibitors, or targeting its downstream gene PBX1 abrogates growth of endocrine therapy-resistant breast cancer cells. Moreover Notch signaling through PBX1 directs a transcriptional program predictive of tumor outcome and endocrine therapy response.
2013-05-01 | GSE37323 | GEO
Project description:*** This submission includes RNA data, with DNA files available under a different accession number*** Purpose: Endocrine therapy resistance remains the greatest challenge for treating hormone receptor positive breast cancer patients. We aim to identify molecular mechanisms underlying endocrine therapy resistance through in-depth genomic analysis of patient samples. Experimental Design: We collected tumors from 35 estrogen receptor positive breast cancer patients receiving endocrine therapy, of which 3 patients had intrinsic resistance and 19 patients developed acquired resistance. For each patient, multiple tumor specimens were collected during the course of treatment. We performed DNA whole exome sequencing and RNA sequencing on all tumor samples. DNA mutations, copy number alterations and RNA gene expression data were analyzed through supervised analyses comparing paired sensitive and resistant tumor samples to identify molecular features related to endocrine therapy resistance. Results: We identified mutations enriched in resistant tumors including ESR1 and GATA3. ESR1 D538G variant confers endocrine therapy resistance while E380Q variant confers hypersensitivity. We demonstrate that resistant tumors had distinct gene expression profiles and elevated signaling pathways including ER, HER2, GATA3, AKT, RAS and p63 signaling. Integrated analysis for individual patient highlighted the heterogeneity of endocrine therapy resistance mechanisms. Conclusions: Our results suggest that mechanisms underlying endocrine therapy resistance are highly heterogeneous with diverse changes in genomic and transcriptomic levels.
2022-09-01 | E-MTAB-9917 | biostudies-arrayexpress
Project description:Epigenetic therapy targets the 3D epigenome in endocrine-resistant breast cancer [WGBS]
| PRJNA996580 | ENA
Project description:The steroid co-activator protein SRC-1 plays an important role in endocrine therapy resistant breast cancer. Its expression is associated with large high grade tumours, HER2 positivity, disease recurrence and resistance to endocrine therapy. SRC-1's role in affecting the transcriptome of the breast cancer endocrine resistant setting is uncovered through this RNA-seq analysis of LY2 cells grown with or without the presence of SRC-1
2018-06-04 | GSE99647 | GEO
Project description:Expression of estrogen receptor (ESR1) determines whether a breast cancer patient receives endocrine therapy as part of their adjuvant care, but does not guarantee patient response. However, the molecular factors that define endocrine response in ESR1-positive breast cancer patients remain poorly understood. Here, we characterize the DNA methylome of endocrine sensitivity and demonstrate the potential impact of differential DNA methylation on endocrine response in breast cancer. We show that DNA hypermethylation occurs predominantly at estrogen-responsive enhancers and is associated with reduced ESR1 binding and decreased gene expression of key regulators of ESR1-activity; thus providing a novel mechanism by which endocrine response is abated in ESR1-positive breast cancers. Conversely, we delineate that ESR1-responsive enhancer hypomethylation is critical in transition from normal mammary epithelial cells to endocrine responsive ESR1-positive cancer. Cumulatively these novel insights highlight the potential of ESR1-responsive enhancer methylation to both predict ESR1-positive disease and stratify ESR1-positive breast cancer patients as responders to endocrine therapy. Methylation profiling with Illumina's HumanMethylation450K array was performed on ESR1-positive hormone sensitive MCF7 cells, and three different well characterised endocrine resistant MCF7-derived cell lines; tamoxifen-resistant (TAMR), fulvestrant-resistant (FASR) and estrogen deprivation resistant (MCF7X) cells. For each cell line two biological replicates were profiled bringing the number of samples to eight.
2015-07-01 | E-GEOD-69118 | biostudies-arrayexpress