Two types of estrogen receptor-positive (ER+) and -negative (ER-) breast cancer will be compared with glycan structure analyses
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ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE32394 | GEO | 2011/09/26
SECONDARY ACCESSION(S): PRJNA147945
REPOSITORIES: GEO
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Project description:ER+ve and ER-ve breast cancers tend to show different patterns of metastasis, with ER+ve tumours having a propensity to metastasize to the bone while ER-ve tumours tend to induce visceral metastasis. Glycans can play an important role in metastasis through their interactions with glycan binding proteins. Moreover we, and others have also shown that expression of particular tumor-associated glycoforms of the mucin MUC1, allows it to interact with lectins of the immune system. We now have data showing differences in the level of expression of some glycosyltransferases in ER+ve and ER-ve of breast cancer suggesting the expression of different O-linked glycoforms. RNA will be isolated from ER+ve and ER-ve primary breast cancers supplied by the Guy’s and St Thomas’ Research Breast Tissue Bank. Tumor tissue will be macro-dissected from thick cryostat sections by visual comparison with a representative H&E section. We will verify the level of expression of ER and document the expression of ST3Gal-I and ST6GalNAc-II by RT-qPCR. We have already isolated RNA from a number of tumours and shown we can obtain RNA of good quality with a RNA integrity number, as measured with an Agilent Bioanalyser, of >4.5 Since there is likely to be variability among primary tumors, ideally we analyzed of 10 ER negative and 9 ER positive tumours.
2011-09-25 | E-GEOD-32394 | biostudies-arrayexpress
Project description:We are currently studying how these information-carrying oligosaccharides are involved in cellular stress responses, particularly in human genetic diseases called Congenital Disorders Of Glycosylation in which oligosaccharide assembly is defective. We are interested in endoplasmic stress responses/unfolded protein responses. ER glycans and ER lectins are intimately involved in the folding of ER proteins. Therefore, ER lectins and ER glycosyltransferases may be controlled by these stress responses, to produce and/or recognize key glycans in the stress response. Our model system is the human dermal fibroblast. We have successfully calibrated the ER stress responses in these cells by determining the magnitudes of various stress effects (such as chaperone transcription) with different forms of ER stress. We are also completing a study in which activation the signaling molecules Ire1 and ATF6 are also calibrated. We prepared multiple identical aliquots of RNA from cells stressed under several of these calibrated conditions.
2011-02-17 | GSE27349 | GEO
Project description:We are currently studying how these information-carrying oligosaccharides are involved in cellular stress responses, particularly in human genetic diseases called Congenital Disorders Of Glycosylation in which oligosaccharide assembly is defective. We are interested in endoplasmic stress responses/unfolded protein responses. ER glycans and ER lectins are intimately involved in the folding of ER proteins. Therefore, ER lectins and ER glycosyltransferases may be controlled by these stress responses, to produce and/or recognize key glycans in the stress response. Our model system is the human dermal fibroblast. We have successfully calibrated the ER stress responses in these cells by determining the magnitudes of various stress effects (such as chaperone transcription) with different forms of ER stress. We are also completing a study in which activation the signaling molecules Ire1 and ATF6 are also calibrated. We prepared multiple identical aliquots of RNA from cells stressed under several of these calibrated conditions. Endoplasmic reticulum (ER) stress and the unfolded protein response (UPR): Study of the role of ER stress in the expression of genes for ER transferases and lectins that participate in ER folding and quality control using human skin fibroblasts. The UPR response in these cells has been calibrated using various readouts in response to different stresses: 1) 40 nM L-azetidine-2-carboxylate (AZC) 1 hour, 2) 0.2 mg/ml castanospermine, 24 hours, 3) 2 mM Dithiothreitol (DTT), 20 minutes, 4) 100nm Thapsigargin (TG), 30 minutes, 5) 5 ug/ml tunicamycin, 5 hours, 6) untreated control cells
2011-02-17 | E-GEOD-27349 | biostudies-arrayexpress
Project description:Divergent estrogen receptor (ER) and HER2 status with breast cancer disease progression has important consequences for clinical management and long-term survival. Molecular subtype expression is dynamic and influenced by therapeutic intervention and the metastatic environment. HER2 status, ER expression levels and global DNA methylation was assessed in pre-treatment biopsies, in post-treatment samples in patients with residual disease and, where relevant, in metastatic tumour samples. Mapping of the methylation landscape revealed global gains in hypomethylation following treatment (n=7 matched tumours, 16 samples) in contrast to hypermethylation on metastasis (n=5 matched tumours, 14 samples). Differential methylation of key signalling pathways, including estrogen response, epithelial to mesenchymal transition and PI3K/AKT/mTOR, is conserved between post-treatment and metastasis. However, where core pathway genes were hypomethylated following treatment, there was a shift to hypermethylation on metastasis, facilitating alterations in the tumour phenotype. This study unlocks DNA methylation as a key process in breast cancer progression providing vital insights into the effects of targeted HER2 treatment. This work provides a clear rationale to develop combined HER2 inhibitor and endocrine therapeutic strategies to enhance long-term survival in HER2 positive patients.
2024-12-16 | GSE283272 | GEO
Project description:Resistance to endocrine treatments and CDK4/6 inhibitors is considered a near-inevitability in most patients with estrogen receptor positive breast cancers (ER + BC). By genomic and metabolomics analyses of patients' tumours, metastasis-derived patient-derived xenografts (PDX) and isogenic cell lines we demonstrate that a fraction of metastatic ER + BC is highly reliant on oxidative phosphorylation (OXPHOS). Treatment by the OXPHOS inhibitor IACS-010759 strongly inhibits tumour growth in multiple endocrine and palbociclib resistant PDX. Mutations in the PIK3CA/AKT1 genes are significantly associated with response to IACS-010759. At the metabolic level, in vivo response to IACS-010759 is associated with decreased levels of metabolites of the glutathione, glycogen and pentose phosphate pathways in treated tumours. In vitro, endocrine and palbociclib resistant cells show increased OXPHOS dependency and increased ROS levels upon IACS-010759 treatment. Finally, in ER + BC patients, high expression of OXPHOS associated genes predict poor prognosis. In conclusion, these results identify OXPHOS as a promising target for treatment resistant ER + BC patients.
2023-06-27 | MTBLS3342 | MetaboLights
Project description:Breast cancer is a heterogeneous disease classified into 3 major subtypes based on the presence or absence of molecular markers for oestrogen receptors (ER), progesterone receptors (PR) and human epidermal growth factor-2 (Her2) . Hormone receptor-positive BC (ER+, PR+ and Her-2-), accounts for approximately 70% of patients. Patients with ER- BC account for approximately 30 % of all cases and commonly have a worse prognosis than ER+ patients (9). However, a significant proportion of ER- cases have good outcomes and could potentially benefit from a less aggressive therapy. Triple negative breast cancer (TNBC, ER-, PR- and Her-2-) accounts for approximately 15% of breast cancers and has the poorest outcomes. An hypoxic microenvironment is an important intrinsic component of solid tumours that can result in rapid proliferation of cancer cells and is associated with the lack of oxgyen and abnormal tumour blood vessels. Hypoxia stimulates the hypoxia inducible factor-1α (HIF-1α) that transactivates genes associated with angiogenesis, tumour growth, metastasis, metabolic reprogramming, and treatment resistance. HIF-1α is recognised to induce the expression of carbonic anhydrase IX (CAIX), an enzyme that has been attributed a central role in pH regulation and cancer progression and is particularly pronounced in peri necrotic tumour areas, high-grade BCs. The adaption to hypoxia is governed by multiple transcriptional and post-transcriptional changes in gene expression. Up to 1.5 % of the human genome is estimated to be transcriptionally responsive to hypoxia. Genes and pathways which have been identified as being responsive to hypoxia may have the potential to be used as prognostic or predictive markers, and furthermore, can help identify novel therapeutic targets. The aim of the present study was to gain a better understanding of the transcriptomic and protein pathways associated with CAIX in ER- BC to identify potential therapeutic targets against this aggressive phenotype.
2023-07-31 | E-MTAB-11955 | biostudies-arrayexpress
Project description:Adjuvant tamoxifen is a valid treatment option for women with estrogen receptor (ER)-positive breast cancer. However, up to 40% of patients experience distant or local recurrence or die. MicroRNAs have been suggested to be important prognosticators in breast cancer. This study aims to identify microRNAs with the potential to predict tamoxifen response. We performed a global microRNA screen in primary tumours of six matched pairs of postmenopausal, ER-positive breast cancer patients treated with tamoxifen, who were either recurrence free or had developed a recurrence. Patients were treated at the Robert Bosch Hospital, Stuttgart, Germany, between 1986 and 2005. Total RNA from FFPE tissue from 12 postmenopausal patients with ER-positive breast cancer (6 patients with and 6 patients without recurrence) was extracted. Hybridisation of biotin-labelled RNA was performed on Affymetrix GeneChip miRNA_2.0 Arrays.
2014-07-01 | E-GEOD-46823 | biostudies-arrayexpress
Project description:Adjuvant tamoxifen is a valid treatment option for women with estrogen receptor (ER)-positive breast cancer. However, up to 40% of patients experience distant or local recurrence or die. MicroRNAs have been suggested to be important prognosticators in breast cancer. This study aims to identify microRNAs with the potential to predict tamoxifen response. We performed a global microRNA screen in primary tumours of six matched pairs of postmenopausal, ER-positive breast cancer patients treated with tamoxifen, who were either recurrence free or had developed a recurrence. Patients were treated at the Robert Bosch Hospital, Stuttgart, Germany, between 1986 and 2005.
2014-07-01 | GSE46823 | GEO
Project description:Dataset containing whole-genome expression profiles of breast cancers at the time of endocrine resistance. It has been used to identify five distinctive phenotypes with different expression of gene clusters associated with ER-signalling, stromal rearrangement and cytokine-signalling. Pathway-focused analysis suggested individual tumours with active ER-signalling (24/55, 44%), PIK3CA-signalling (18/55, 32%), RAS (12/55, 22%) and MYC-signalling (11/55, 20%). 3 or 4 of the above pathways were simultaneously active in 6/55 (11%) cases. Results provide important information about prevalence of different mechanisms of endocrine resistance in clinical samples of breast cancer. Please note that the tumor samples are clinically quite homogeneous: all are post-menopausal ER+ve breast cancers, endocrine treated and growing on treatment. The main purpose of collecting these data was not to compare transcriptional profiles with clinical parameters, but rather to use the transcriptional profiles of these clinically homogeneous tumours for identifying intrinsic subgroups within endocrine resistance. However, the relevant clinical data was also provided as Series supplementary file (ClinicalData_AL28Jan2014.xlsx).
2014-12-01 | GSE54479 | GEO
Project description:G0/G1 switch gene 2 (G0S2) is known to inhibit lipolysis through inhibition of adipose triglyceride lipase (ATGL). Although G0S2 has also been proposed to be involved in cancer progression, this role appears complex, and mechanisms are unclear. We recently reported a role for G0S2 in ER+ breast cancer suppression as low G0S2 expression correlated with increased recurrence after antiestrogen therapy and increased G0S2 expression sensitized ER+ breast cancer cells to tamoxifen and PI3K/mTOR inhibitors. In this report we dissect the role of G0S2 in ER+ versus ER- breast cancer. Overexpression of G0S2 in ER- breast cancer cells increased cell proliferation while G0S2 overexpression in ER+ breast cancer cells decreased cell proliferation. Transcriptome analysis revealed that G0S2 mediated distinct but overlapping transcriptional responses in ER- and ER+ cells. G0S2 reduced genes associated with an epithelial phenotype, especially in ER- cells, including CDH1, ELF3, STEAP4 and TACSTD2 suggesting promotion of the epithelial-mesenchymal transition (EMT). G0S2 also repressed estrogen signaling and estrogen receptor target gene signatures, especially in ER+ cells, including TFF1 and TFF3. In addition, G0S2 overexpression increased cell migration in ER- cells and increased estrogen deprivation sensitivity in ER+ cells. Interestingly, two genes downstream of ATGL in fat utilization, HMGCS1 and HMGCS2, that are also rate-limiting in steroid hormone biosynthesis, were downregulated in G0S2 overexpressing ER+ cells. In addition, HSD17B11, a gene that converts estradiol to its less estrogenic derivative, estrone, was highly upregulated in G0S2 overexpressing ER+ cells, suggesting G0S2 overexpression has a negative effect of estradiol production and maintenance. High levels of estrone were confirmed to be present in G0S2 overexpressing cells. High expression of G0S2 and HSD17B11 was associated with improved relapse free survival in breast cancer patients while high expression of HMGSC1 was associated with poor survival. In addition, the expression of G0S2 positively and negatively correlated respectively, with expression of HSD17B11 and HMGSC1 in patient samples. Finally, we deleted G0S2 in breast cancer prone MMTV-PyMT mice that have been hypothesized to be partially estrogen sensitive during early stages of tumorigenesis but develop ER- tumors. In this context, G0S2 functioned as a tumor promoter, with G0S2 null mice demonstrating a slight increase in tumor latency and decrease in tumor weight and a larger inhibitory effect on tumor metastasis. Our data indicates a complex role for G0S2 in breast cancer, dependent on ER status, that may be mediated in part by suppression of the estrogen signaling pathway.
2023-04-11 | GSE227698 | GEO