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GSE74391
Homo sapiens
22 Downloadable Samples
Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Purpose: Resistance to endocrine therapy in estrogen receptor-positive (ER+) breast cancer remains a major clinical problem. Recently, the CDK4/6 inhibitor palbociclib combined with letrozole was approved for treatment of ER+ advanced breast cancer, and other CDK4/6 inhibitors are being investigated in combination with different endocrine treatments. However, the role of CDK4/6 in endocrine resistance and their potential as predictive biomarkers of endocrine treatment response remains undefined.
Publication Title
High CDK6 Protects Cells from Fulvestrant-Mediated Apoptosis and is a Predictor of Resistance to Fulvestrant in Estrogen Receptor-Positive Metastatic Breast Cancer.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 17 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
To elucidate the molecular mechanisms of tamoxifen resistance in breast cancer, we performed gene array analysis and identified 366 genes with altered expression in four unique tamoxifen resistant (TamR) cell lines vs the parental tamoxifen sensitive MCF7/S0.5 cell line. Most of these genes were funcationally linked to cell proliferation, death and control gene expression, and include FYN, PRKCA, ITPR1, DPYD, DACH1, LYN, GBP1 and PRLR. Treatment with FYN specific small interfering RNA or a SRC family kinase inhibitor reduced cell growth of TamR cell lines while exerting no significant effect on MCF7/S0.5 cells. Moreover, overexpression of FYN in parental tamoxifen-sensitive MCF7/S0.5 cells resulted in reduced sensitivity to tamoxifen, demonstrating growth and survival promoting function of FYN in MCF7 cells. FYN knockdown in TamR cells led to reduced phosphorylation of 14-3-3 and CDc 25A, suggesting that FYN, by activation of of important cell cycle-associated proteins, may overcome the anti-proliferative effects of tamoxifen. Evaluation of the subcellular localization of FYN in primary breast tumors from two cohorts of endocrine-treated ER+ breast cancer patients, one with advanced disease (N = 47) and the other with early disease (N = 76), showed that in the former, plasma membrane-associated FYN expression strongly correlated with longer progression-free survival (P<0.0002). Similarly, in early breast cancer patients, membrane-associated expression of FYN in the primary breast tumor was significantly associated with increased metastasis-free (P<0.04) and overall (P<0.004) survival independent of tumor size, grade or lymph node status. Our results indicate that FYN has an important role in tamoxifen resistance, and its subcellular localization in breast tumor cells may be an important novel biomarker of response to endocrine therapy in breast cancer.
Publication Title
Gene expression profiling identifies FYN as an important molecule in tamoxifen resistance and a predictor of early recurrence in patients treated with endocrine therapy.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Homo sapiens
- 10 Downloadable Samples
- Affymetrix Human Gene 1.0 ST Array (hugene10st)
Description
The CD44hi compartment in human breast cancer is enriched in tumor-initiating cells, however the functional heterogeneity within this subpopulation remains poorly defined. From a human breast cancer cell line with a known bi-lineage phenotype we have isolated and cloned two CD44hi populations that exhibited mesenchymal/Basal B and luminal/Basal A features, respectively. Rather than CD44+/CD24-,Basal B (G4) cells, only CD44hi/CD24lo, epithelioid Basal A (A4) cells retained a tumor-initiating capacity in NOG mice, form mammospheres and exhibit resistance to standard chemotherapy.
Publication Title
Functional heterogeneity within the CD44 high human breast cancer stem cell-like compartment reveals a gene signature predictive of distant metastasis.
Sample Metadata Fields
Specimen part, Disease, Disease stage
View Samples- Mus musculus
- 2 Downloadable Samples
- Affymetrix Mouse Expression 430A Array (moe430a)
Description
DLK1/FA-1 (delta-like 1/fetal antigen-1) is a transmembrane protein belonging to Notch/Delta family that acts as a membrane-associated or a soluble protein to regulate regeneration of a number of adult tissues. Here, we examined the role of DLK1/FA-1 in bone biology using osteoblast-specific-Dlk1 over-expressing mice (Col1-Dlk1). Col1-Dlk1 mice displayed growth retardation and significantly reduced total body weight and bone mineral density (BMD). CT-scanning revealed a reduced trabecular and cortical bone volume fraction. Tissue-level histomorphometric analysis demonstrated decreased bone formation rate and enhanced bone resorption in Col1-Dlk1 as compared to WT. At a cellular level, DLK1 markedly reduced the total number of bone marrow (BM)-derived CFU-F, as well as their osteogenic capacity. In a number of in vitro culture systems, DLK1 stimulated osteoclastogenesis indirectly through osteoblast-dependent increased production of pro-inflammatory bone resorbing cytokines (e.g, Il7, Tnfa and Ccl3). We found that ovariectomy (ovx)-induced bone loss was associated with increased production of DLK1 in bone marrow by activated T-cells. However, Dlk1-/- mice were protected from ovx-induced bone loss. Thus, we identified DLK1 as a novel regulator of bone mass that function to inhibit bone formation and to stimulate bone resorption. Increasing DLK1 production by T-cells under estrogen deficiency suggests its possible use as a therapeutic target for preventing postmenopausal bone loss.
Publication Title
DLK1 is a novel regulator of bone mass that mediates estrogen deficiency-induced bone loss in mice.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 5 Downloadable Samples
Description
Purpose: Development of resistance to tamoxifen is an important clinical issue in the treatment of patients with breast cancer. Tamoxifen resistance may be the result of the acquisition of epigenetic regulation such as DNA methylation within breast cancer cells resulting in changed mRNA expression of genes being pivotal for estrogen dependent growth. Alternatively, tamoxifen resistance may be due to selection of preexisting resistant cells, which may exhibit cancer stem-like characteristics or a combination of the two mechanisms. Methods: To evaluate the contribution of these possible mechanisms to tamoxifen resistance, we applied modified DNA methylation-specific digital karyotyping (MMSDK) and digital gene expression (DGE) in combination with massively parallel sequencing to analyze a well-established tamoxifen resistant cell line model: MCF-7/S0.5 (tamoxifen sensitive parental cell line) and 4 high-dosage tamoxifen selected resistant offspring sublines (MCF-7/TAMR-1, MCF-7/TAMR-4, MCF-7/TAMR-7 and MCF-7/TAMR-8). MMSDK uses BssHII as mapping enzyme (DNA methylation sensitive enzyme). Both MMSDK and DGE use NlaIII and MmeI to produce 20-21 bp tag. The indexed single-end sequencing was performed by Illumina HiSeq 2000 in BGI-Shenzhen. A dynamic programming algorithm-FASTX-Toolkit implemented in Perl was used to trim the adaptor sequence. The trimmed tags were subjected to quality filtering, so that only tags with sequencing quality higher than 30 for more than 80% of the nucleotides were used for subsequent analysis. For MMSDK tag mapping, we generated a simulated reference library, i.e., BssHII reference library, by in silico enzyme digestion of the human genome (hg19, UCSC) regardless of the methylation state. This library was used as reference for subsequent mapping of the tags in the MMSDK analysis. In the DGE analysis, refMrna (hg19, UCSC) was used as reference for mapping cDNA tags. Subsequently, the Burrows–Wheeler Aligner (BWA) procedure for aligning the MMSDK and DGE tags to the simulated BssHII reference library and refMrna reference library, respectively, was applied. Results: MMSDK libraries using BssHII/NlaIII were generated from the parental tamoxifen sensitive subline MCF-7/S0.5 and the 4 TAMR cell lines: TAMR-1, TAMR-4, TAMR-7 and TAMR-8. The 5 indexed MMSDK libraries were sequenced in one lane and 1.38 Gb clean tag data for all 5 cell lines were obtained, with an average sequencing amount of ~270 Mb per library. On average, 59.5 % of the tags with mapping quality = 20 were mapped back to the simulated BssHII/NlaIII reference library. DGE libraries were also generated from MCF-7/S0.5 and the 4 TAMR cell lines. The 5 indexed DGE libraries were sequenced in one lane and obtained 1.71 Gb clean tag data for all 5 cell lines with an average sequencing amount of ~340 Mb per library. On average, 40.8 % with mapping quality = 20 were mapped back to the simulated NlaIII human transcriptome (refMrna reference library). Our present study demonstrates large differences in global gene expression and DNA methylation profiles between parental tamoxifen-sensitive cell line and 4 high-dosage tamoxifen treatment selected resistant sublines. The tamoxifen resistant cell lines exhibited globally higher methylation level than the parental cell line and an inverse relationship between gene expression and DNA methylation in the promoter regions were noticed. High expression of SOX2 and alterations of other SOX gene family members, E2F gene family members and RB-related pocket protein genes as well as highlighted stem cell pathways imply that cancer initiating cells/stem cells are involved in the resistance to tamoxifen. Overall design: DNA methylation and mRNA expression profiles from tamoxifen sensitive parental cell line MCF-7/S0.5 and 4 high dosage of tamoxifen selected resistant offspring sublines (MCF-7/TAMR-1, MCF-7/TAMR-4, MCF-7/TAMR-7 and MCF-7/TAMR-8) were analyzed by MMSDK and DGE methods, respectively, in combination of massively parallel sequencing, using Illumina HiSeq 2000
Publication Title
Integrative analyses of gene expression and DNA methylation profiles in breast cancer cell line models of tamoxifen-resistance indicate a potential role of cells with stem-like properties.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 5 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
To identify the genes and pathways regulated by FOXF2, we investigated potential FOXF2 gene targets by microarray analyses of primary prostate stromal cells (PrSC) in which FOXF2 was knocked down by siRNA. 190 differentially expressed genes were selected, of which 104 genes were more highly expressed in PrSC cells treated with FOXF2 siRNA and 86 were more highly expressed in PRSC cells treated with negative control siRNA.
Publication Title
The FOXF2 pathway in the human prostate stroma.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 42 Downloadable Samples
- Affymetrix Human Exon 1.0 ST Array [transcript (gene) version (huex10st)
Description
Long non-coding RNAs show highly tissue and disease specific expression profiles. We analyzed prostate cancer and normal adjacent prostate samples to identify cancer-specific transcripts and found 334 candidates, of which 15 were validated by RT-PCR.
Publication Title
Novel long non-coding RNAs are specific diagnostic and prognostic markers for prostate cancer.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 6 Downloadable Samples
- Affymetrix Human Genome U133A Array (hgu133a)
Description
RhoGDIbeta (ARHGDIB) is often expressed in tumor cells. It negatively regulates Rho-GTPases, but may have other functions as well. To analyze its effect on gene expression, RhoGDIbeta was suppressed by RNA interference in MDA-MB-231 breast cancer cells and changes in gene expression monitored by cDNA microarrays.
Publication Title
Cyclooxygenase-2 is a target gene of rho GDP dissociation inhibitor beta in breast cancer cells.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 74 Downloadable Samples
- Illumina HiSeq 2000
Description
Ubiquitous expression of ALS-causing mutations in superoxide dismutase 1 (SOD1) provoke non-cell autonomous paralytic disease. By combining ribosome affinity purification and high-throughput sequencing, a cascade of mutant SOD1-dependent, cell type-specific changes are now identified. Initial mutant-dependent damage is restricted to motor neurons and includes synapse and metabolic abnormalities, endoplasmic reticulum (ER) stress, and selective activation of the PERK arm of the unfolded protein response. PERK activation correlates with what we identify to be a naturally low level of ER chaperones in motor neurons. Early changes in astrocytes are to genes involved in inflammation and metabolism and that are targets of the PPAR and LXR transcription factors. Dysregulation of myelination and lipid signaling pathways and activation of ETS transcription factors occur in oligodendrocytes only after disease initiation. Thus, pathogenesis involves a temporal cascade of cell type selective damage initiating in motor neurons, with subsequent damage within glia driving disease propagation. Overall design: Cell type-specific mRNA was purified by ribosome affinity purification from the spinal cord of bacTRAP reporter mice that label selective cell types by EGFP-tagged ribosome RPL10A. Sequencing libraries were prepared from 3-6 biological replicates for each genotype to determine the mutant induced gene expression changes in specific cell types.
Publication Title
Translational profiling identifies a cascade of damage initiated in motor neurons and spreading to glia in mutant SOD1-mediated ALS.
Sample Metadata Fields
Sex, Specimen part, Disease stage, Subject
View Samples- Homo sapiens
- 55 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
A biobank of patient-derived pediatric brain tumor models.
Sample Metadata Fields
No sample metadata fields
View Samples