Progesterone receptors (PRs) are critical context-dependent transcription factors required for normal uterine (PR-A) and mammary gland (PR-B) development. Progesterone is proliferative in the breast, where PR-target genes include paracrine factors that mediate mammary stem cell self-renewal. In the context of altered signal transduction that typifies breast tumorigenesis, dysregulated (i.e. hyper-phosphorylated) PRs likely contribute to tumor progression by promoting cancer cell pro-survival and proliferation. Notably, in breast cancer cells, progestin-bound PRs induce rapid MAPK activation leading to selective regulation of growth-promoting genes by phosphorylated PR species. Functional domains within PR that interact with c-Src and estrogen receptors (ER) have been identified as indirect routes to MAPK activation. Herein, we describe a common docking (CD) domain located within the PR-B N-terminus, a motif first described in MAPKs that facilitates direct interactions between MAPKs and MEK1 or MAPK-phosphatases (MKPs). Mutation of negatively-charged amino acids, previously determined to be critical for CD domain function in MAPKs, within PR-B (mCD PR) did not alter MEK-binding or progestin-induced rapid signaling (i.e. MAPK activation) and PR transcriptional activity as measured by PRE-luciferase (reporter) assays. Microarray gene-expression analysis revealed that endogenous genes regulated by wt PR, but not mCD PR, are involved in critical cellular pathways regulating growth, proliferation, survival, and cancer. mCD PR failed to undergo ligand-induced phosphorylation on Ser81, a ck2-dependent site required for progestin-regulation of select growth-promoting genes (BIRC3, HSD112, HbEGF). Progestin-induced PR Ser81 phosphorylation mapped to CD domain-dependent binding of PR-B to MKP3, but did not require phosphatase activity. Receptors containing either mutant CD domains (mCD PR) or point mutations of Ser81 (S79/81A PR) failed to upregulate STAT5 and Wnt1, key PR-target gene products that act as critical mediators of mammary stem cell expansion. Inhibition of JAK/STAT signaling blocked progestin-induced STAT5 and Wnt1 expression. ChIP assays demonstrated that wt, but not phospho-mutant (S79/81A), PR-B was co-recruited to a PRE-containing enhancer region of the Wnt1 gene along with MKP3, ck2 and STAT5. Our studies reveal a novel scaffolding action of MKP3 mediated by interaction with the PR CD domain and required for ck2-dependent PR Ser81 phosphorylation. Co-regulation of select target genes by phospho-Ser81 PR and phospho-STAT5 is likely a global mechanism required for the activation of growth promoting programs active during normal mammary gland development and relevant to mechanisms of breast cancer progression.
A Common Docking Domain in Progesterone Receptor-B links DUSP6 and CK2 signaling to proliferative transcriptional programs in breast cancer cells.
Specimen part, Treatment
View SamplesWe reported that NRP-1 expression on CD4+ T cells was probably induced by NRP-1 transfer from macrophages to T cells. In HER2+ BC, NRP-1 expressing TIIs correlated with better clinical outcomes. Overall design: Examination of monocytes and monocyte derived macrophages.
Downregulation of neuropilin-1 on macrophages modulates antibody-mediated tumoricidal activity.
No sample metadata fields
View SamplesHere we uncover antagonistic regulation of transcript levels in the germline of Caenorhabditis elegans hermaphrodites. The histone methyltransferase MES-4 marks genes expressed in the germline with methylated Lys36 on histone H3 (H3K36me) and promotes their transcription; MES-4 also represses genes normally expressed in somatic cells and genes on the X chromosomes. The DRM complex, which includes E2F/DP and Retinoblastoma homologs, affects germline gene expression and prevents excessive repression of X-chromosome genes. Using genome-scale analyses of germline tissue, we show that common germline-expressed genes are activated by MES-4 and repressed by DRM, and that MES-4 and DRM co-bind many germline-expressed genes. Reciprocally, MES-4 represses and DRM activates a set of autosomal soma-expressed genes and overall X-chromosome gene expression. Mutations in mes-4 or the DRM subunit lin-54 oppositely skew target transcript levels and cause sterility; a double mutant restores near wild-type transcript levels and germ cell development. Together, yin-yang regulation by MES-4 and DRM ensures transcript levels appropriate for germ cell function, elicits robust but not excessive dampening of X-chromosome-wide transcription, and may poise genes for future expression changes. Our study reveals that conserved transcriptional regulators implicated in development and cancer counteract each other to fine-tune transcript dosage.
Opposing activities of DRM and MES-4 tune gene expression and X-chromosome repression in Caenorhabditis elegans germ cells.
Sex
View SamplesHuman genome-wide Affymetrix GeneChip arrays were used to compare the levels of gene expression in the peripheral blood mononuclear cells (PMBCs) of male patients with post-viral chronic fatigue (n=8) and male healthy control subjects (n=7). Patients and healthy subjects differed significantly in the level of expression of 366 genes. Analysis of the differentially expressed genes indicated functional implications in immune modulation, oxidative stress and apoptosis. Prototype biomarkers were identified on the basis of differential levels of gene expression and possible biological significance. Differential expression of key genes identified in this study offer an insight into the possible mechanism of chronic fatigue following infection. The representative biomarkers identified in this research appear promising as potential biomarkers for diagnosis and treatment.
A gene signature for post-infectious chronic fatigue syndrome.
No sample metadata fields
View SamplesCancer cells consume large amounts of glucose because of their specific metabolic pathway. However, cancer cells exist in tumor tissue where glucose is insufficient. To survive, cancer cells likely have the mechanism to elude their glucose addiction. Here we show that functional mitochondria are essential if cancer cells are to avoid glucose addiction.
Mitochondria regulate the unfolded protein response leading to cancer cell survival under glucose deprivation conditions.
Disease, Cell line, Time
View SamplesMitochondria can be involved in regulating cellular stress response to hypoxia and tumor growth, but little is known about that mechanistic relationship. Here, we show that mitochondrial deficiency severely retards tumor xenograft growth with impairing hypoxic induction of HIF-1 transcriptional activity. Using mtDNA-deficient rho0 cells, we found that HIF-1 pathway activation was comparable in slow-growing rho0 xenografts and rapid-growing parental xenografts. Interestingly, we found that ex vivo rho0 cells derived from rho0 xenografts exhibited slightly increased HIF-1alpha expression and modest HIF-1 pathway activation regardless of oxygen concentration. Surprisingly, rho0 cells, as well as parental cells treated with oxidative phosphorylation inhibitors, were unable to boost HIF-1 transcriptional activity during hypoxia, although HIF-1alpha protein levels were ordinarily increased in these cells under hypoxic conditions. These findings indicate that mitochondrial deficiency causes loss of hypoxia-induced HIF-1 transcriptional activity and thereby might lead to a constitutive HIF-1 pathway activation as a cellular adaptation mechanism in tumor microenvironment.
Mitochondrial deficiency impairs hypoxic induction of HIF-1 transcriptional activity and retards tumor growth.
Cell line
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Chromosome-biased binding and gene regulation by the Caenorhabditis elegans DRM complex.
Specimen part
View SamplesDRM is a conserved transcription factor complex that includes E2F/DP and pRB family proteins and plays important roles in development and cancer. Here we perform microarray expression profiling analysis of lin-54, a DNA-binding member of the DRM complex. To identify genes regulated by LIN-54 in soma and germline, we analyzed wild-type and lin-54 mutant C. elegans embryos and isolated germlines. We chose embryos because they consist primarily of somatic cells, at a developmental stage with both active cell divisions and dynamic developmental gene expression programs. Since lin-54 null animals are sterile, embryos were obtained from a strain carrying the partial loss-of-function allele lin-54(n2990). Germlines were dissected from lin-54(n3423) null adults that lack detectable transcript and protein. The results revealed conserved roles for DRM in regulating genes involved in cell division, development, and reproduction. We find LIN-54 promotes expression of reproduction genes in the germline, but prevents ectopic activation of germline-specific genes in embryonic soma. Strikingly, genomics and cytological analyses show that DRM binding, a DRM binding motif, and LIN-54-regulated genes are all autosome-enriched. One paradoxical exception occurs the germline, where DRM binds autosomes but genes down-regulated in DRM mutants are enriched on X chromosomes.
Chromosome-biased binding and gene regulation by the Caenorhabditis elegans DRM complex.
Specimen part
View SamplesTo determine the potential mechanisms by which AID-elimination facilitate better J558 tumor rejection by P1CTL, we performed cDNA microarray analysis to compare AID-silenced J558 cells and their relative controls.
Targeting activation-induced cytidine deaminase overcomes tumor evasion of immunotherapy by CTLs.
Specimen part
View SamplesInduction of germline-competent pluripotent stem cells from mouse fibroblasts has been achieved by the ectopic expression of four genes (Oct3/4, Sox2, c-Myc and Klf4). If this method can be applied to humans for the generation of personalized human pluripotent stem cells, it would greatly facilitate the therapeutic application of stem cells by avoiding the problem of immune rejection by the recipient associated with allograft transplants. Here we show that the ectopic expression of the same four genes in human neonatal skin derived cells is sufficient to induce pluripotent stem cells indistinguishable from human embryonic stem cells in morphology, gene expression, DNA methylation, teratoma formation and long term self-renewal ability. Extensive analysis of colonies generated by ectopic expression of these four genes indicates the presence of considerable heterogeneity in the induced colonies. These results provide a new finding to generate human induced pluripotent stem cells from postnatal somatic tissues.
Heterogeneity of pluripotent marker gene expression in colonies generated in human iPS cell induction culture.
No sample metadata fields
View Samples