Resistance to tamoxifen in breast cancer patients is a serious therapeutic problem and major efforts are underway to understand underlying mechanisms. Resistance can be either intrinsic or acquired. We derived a series of subcloned MCF7 cell lines that were either highly sensitive or naturally resistant to tamoxifen and studied the factors that lead to drug resistance. Gene-expression studies revealed a signature of 67 genes that differentially respond to tamoxifen in sensitive vs. resistant subclones, which also predicts disease-free survival in tamoxifen-treated patients. High-throughput cell-based screens, in which >500 human kinases were independently ectopically expressed, identified 31 kinases that conferred drug resistance on sensitive cells. One of these, HSPB8, was also in the expression signature and, by itself, predicted poor clinical outcome in one cohort of patients. Further studies revealed that HSPB8 protected MCF7 cells from tamoxifen and blocked autophagy. Moreover, silencing HSBP8 induced autophagy and caused cell death. Tamoxifen itself induced autophagy in sensitive cells but not in resistant ones, and tamoxifen-resistant cells were sensitive to the induction of autophagy by other drugs. These results may point to an important role for autophagy in the sensitivity to tamoxifen.
High-throughput ectopic expression screen for tamoxifen resistance identifies an atypical kinase that blocks autophagy.
Specimen part, Cell line
View SamplesEarly innate lymphoid progenitors (EILP) have recently been identified in the mouse adult bone marrow as a multipotential progenitor population committed to ILC lineages, but their relationship with other described ILC progenitors is still unclear. In this study, we examine the progenitor-successor relationships between EILP, IL-7R+ common lymphoid progenitors (ALP), and ILC precursors (ILCp). Bioinformatic, phenotypical, functional, and genetic approaches collectively establish EILP as an intermediate progenitor between ALP and ILCp. Our work additionally provides new candidate regulators of ILC development and clearly defines the stage of requirement of transcription factors key for early ILC development. Overall design: transcriptional profiling of early ILC progenitors (EILP, ILCp), and common lymphoid progenitors (ALP) was performed by RNA sequencing
Development and differentiation of early innate lymphoid progenitors.
Specimen part, Cell line, Subject
View SamplesThe molecular basis of breast cancer invasion and metastasis is not well understood. Our objective was to analyze transcriptome differences between stromal and epithelial cells in normal breast tissue and invasive breast cancer to define the role stroma plays in invasion. Total RNA was isolated from epithelial and stromal cells that were laser captured from normal breast tissue (n=5) and invasive breast cancer (n=28). Gene expression was measured using Affymetrix U133A 2.0 GeneChips. Differential gene expression was evaluated and compared within a model that accounted for cell type (epithelial [E] versus stromal [S]), diagnosis (cancer [C] versus normal [N]) as well as cell type-diagnosis interactions. Compared to NE, the CE transcriptome was highly enriched with genes in proliferative, motility and ECM ontologies. Differences in CS and NS transcriptomes suggested that the ECM was being remodeled in invasive breast cancer, as genes were over-represented in ECM and proteolysis ontologies. Genes more highly expressed in CS compared to CE were primarily ECM components or were involved in the remodeling of ECM, suggesting that ECM biosynthesis and remodeling were initiated in the tumor stromal compartment.
Molecular signatures suggest a major role for stromal cells in development of invasive breast cancer.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Chromatinized protein kinase C-θ directly regulates inducible genes in epithelial to mesenchymal transition and breast cancer stem cells.
Cell line, Treatment
View SamplesEpithelial to mesenchymal transition (EMT) is activated during cancer invasion and metastasis, enriches for cancer stem cells (CSCs), and contributes to therapeutic resistance and disease recurrence. The epithelial cell line MCF7, can be induced to undergo EMT with the induction of PKC by PMA. 5-10% of the resulting cells have a CSC phenotype. This study looks at the transcriptome of these cells and how it differs from cells with a non-CSC phenotype.
Chromatinized protein kinase C-θ directly regulates inducible genes in epithelial to mesenchymal transition and breast cancer stem cells.
Cell line, Treatment
View SamplesDespite the frequent detection of circulating tumor antigen-specific T cells, either spontaneously or following active immunization or adoptive transfer, immune-mediated cancer regression occurs only in the minority of patients. One theoretical rate-limiting step is whether effector T cells successfully migrate into metastatic tumor sites. Affymetrix gene expression profiling performed on a series of metastatic melanoma biopsies revealed a major segregation of samples based on the presence or absence of T cell-associated transcripts. The presence of lymphocytes correlated with the expression of defined chemokine genes. A subset of 6 chemokines (CCL2, CCL3, CCL4, CCL5, CXCL9, and CXCL10) was confirmed by protein array and/or quantitative RT-PCR to be preferentially expressed in tumors that contained T cells. Corresponding chemokine receptors were found to be upregulated on human CD8+ effector T cells, and transwell migration assays confirmed the ability of each of these chemokines to promote migration of CD8+ effector cells in vitro. Screening by chemokine protein array identified a subset of melanoma cell lines produced a similar broad array of chemokines. These melanoma cells more effectively recruited human CD8+ effector T cells when implanted as xenografts in NOD/scid mice in vivo. Chemokine blockade with specific antibodies inhibited migration of CD8+ T cells. Our results suggest that lack of critical chemokines in a subset of melanoma metastases may limit the migration of activated T cells, which in turn could limit the effectiveness of anti-tumor immunity.
Chemokine expression in melanoma metastases associated with CD8+ T-cell recruitment.
No sample metadata fields
View SamplesTo examine the transcriptome of early testicular somatic cells during gonadogenesis at 12.5dpc RNA sequencing (RNA-Seq) was performed on murine primary testicular cell lineages isolated from the Sf1-eGFP line by FACS. The three main somatic cell lineages of the testis were isolated: the Sertoli cells which direct male development; the fetal Leydig cells (FLCs) that produce steroid hormones and virilise the XY individual and a heterogenous population of interstitial cells, some of which give rise to the adult Leydig cells (ALCs). This dataset provides a platform for exploring the biology of FLCs and understanding the role of these cells in testicular development and masculinization of the embryo, and a basis for targeted studies designed to identify causes of idiopathic XY DSD. Overall design: RNA-Seq of 3 enriched cell populations from 12.5dpc mouse gonad (Sertoli cells, Leydig cells and Interstitial cells isolated by FACS-sorting) on an Illumina HiSeq 1500, in triplicate.
Purification and Transcriptomic Analysis of Mouse Fetal Leydig Cells Reveals Candidate Genes for Specification of Gonadal Steroidogenic Cells.
No sample metadata fields
View SamplesTFH and Th1 cells generated after viral or intracellular bacterial infections are critical for the control of infections and the development of immunological memories. However, the mechanisms that govern the choice of activated CD4 T cells to the two alternative fates remain unclear. Here, we found that reciprocal expression of TCF1 and Blimp1 between viral-specific TFH and Th1 cells started early after infection. TCF1 was intrinsically required for the differentiation of TFH cells. In the absence of TCF1, TFH cells failed to maintain their transcriptional and metabolic signatures, distinct from those in Th1 cells. Mechanistically, TCF1 functioned through forming negative feedback loops with IL-2 and Blimp1 signaling. Thus, we have demonstrated an essential role of TCF1 in TFH-cell differentiation.
TCF1 Is Required for the T Follicular Helper Cell Response to Viral Infection.
Specimen part
View SamplesMicroRNAs (miRNAs) have been implicated as fine-tuning regulators controlling diverse biological processes at the level of posttranscriptional repression. Dysregulation of miRNAs has been described in various disease states, including inflammatory autoimmune diseases.
The microRNA miR-23b suppresses IL-17-associated autoimmune inflammation by targeting TAB2, TAB3 and IKK-α.
Sex, Specimen part
View SamplesWe found microRNA miR-23b was down-regulated in local inflammatory tissues of autoimmune disease such as RA, SLE and related mouse models such as CIA, lpr, EAE. Re-expression of miR-23b significantly inhibits autoimmune pathogenesis of CIA, Lpr and EAE.
The microRNA miR-23b suppresses IL-17-associated autoimmune inflammation by targeting TAB2, TAB3 and IKK-α.
Specimen part
View Samples