Severe malnutrition in young children is associated with signs of hepatic dysfunction such as steatosis and hypoalbuminemia, but its etiology is unknown. To investigate the underlying mechanisms of hepatic dysfunction we used a rat model of malnutrition by placing weanling rats on a low protein or control diet (5% or 20% of calories from protein, respectively) for four weeks. Low protein diet-fed rats developed hypoalbuminemia and severe hepatic steatosis, consistent with the human phenotype. Hepatic peroxisome content was decreased and metabolomic analysis indicated impaired peroxisomal function. Loss of peroxisomes was followed by accumulation of dysfunctional mitochondria and decreased hepatic ATP levels. Fenofibrate supplementation restored hepatic peroxisome abundance and increased mitochondrial fatty acid -oxidation capacity, resulting in reduced steatosis and normalization of ATP and plasma albumin levels. These findings provide important insight into the metabolic
Malnutrition-associated liver steatosis and ATP depletion is caused by peroxisomal and mitochondrial dysfunction.
Sex, Specimen part, Treatment
View SamplesTumor associated macrophages show signs of both, classical pro-inflammatory as well as alternative macrophage activation. The aim of this study was to compare TAMs across tumor types, to characterize their phenotype in detail and to identify the signaling nodules involved regulating classical and alternative activation traits.
Myeloid-derived suppressor activity is mediated by monocytic lineages maintained by continuous inhibition of extrinsic and intrinsic death pathways.
Specimen part
View SamplesAnalysis of estrogen receptor (ER)-positive MCF7 cell total RNA expression and polysome-assiciated RNA expression following treatment with estradiol (E2) and vehicle (etoh).
Estrogen coordinates translation and transcription, revealing a role for NRSF in human breast cancer cells.
Cell line
View SamplesTumor growth is associated with a profound alteration of myelopoiesis, leading to recruitment of immunosuppressive cells known as myeloid-derived suppressor cells (MDSCs). Immuno-regulatory activity of both tumor-induced and BM-derived MDSCs (by GM-CSF and IL-6 treatment) was entirely dependent on C/EBP transcription factor (TF), a key component of the emergency myelopoiesis triggered by stress and inflammation. We used miR expression analysis to identify miRs which could drive MDSC recruitment/generation/activity by modulating specific TFs and pathway. In particular, we identified a miR signature of 79 miR differentially expressed between not suppressive CD11b+ cells and CD11b+ isolated from tumor mass and spleen of tumor-bearing mice. Moreover on the same samples we profiled gene expression with Affymetrix microarrays to perform an integrated analysis of mirna and gene expression.
miR-142-3p prevents macrophage differentiation during cancer-induced myelopoiesis.
Specimen part, Disease, Disease stage, Cell line
View SamplesTumor progression is accompanied by an altered myelopoiesis that causes the accumulation of cells inhibiting anti-tumor T lymphocytes. We previously reported that immunosuppressive cells can be generated in vitro from bone marrow cells (BM) after four days GM-CSF and IL-6 treatment. Here, we describe that miR-142-3p down-regulation directs macrophage differentiation and determines the acquisition of their immunosuppressive function in cancer. Enforced miR over-expression impaired monocyte to macrophage transition both in vitro and in vivo. Conversely, forced miR down-regulation promoted the generation of immunosuppressive macrophages even during G-CSF-induced granulocytic differentiation. To identify how miR-142-3p regulates MDSC generation and activity, we analyze the gene expression of BM cultures transfected with either CTRL- or miR 142-3p mimic oligo -transfected before four days GM-CSF and IL-6 treatment.
miR-142-3p prevents macrophage differentiation during cancer-induced myelopoiesis.
Specimen part, Treatment
View SamplesTumor growth is associated with a profound alteration of myelopoiesis, leading to recruitment of immunosuppressive cells known as myeloid-derived suppressor cells (MDSCs). Analyzing the cytokines affecting myelo-monocytic differentiation produced by various experimental tumors, we found that GM-CSF, G-CSF, and IL-6 allowed a rapid generation of MDSCs from precursors present in mouse and human bone marrow (BM). BM-MDSCs induced by GM-CSF+IL-6 possessed the highest tolerogenic activity, as revealed by the ability to impair the priming of IFN- -producing CD8+ T cells upon in vivo adoptive transfer. Moreover, adoptive transfer of syngeneic, GM-CSF+IL-6-conditioned MDSCs to diabetic mice transplanted with allogeneic pancreatic islets resulted in long term acceptance of the allograft and correction of the diabetic status. Cytokines inducing MDSCs acted on a common molecular pathway. Immunoregulatory activity of both tumor-induced and BM-derived MDSCs was entirely dependent on C/EBP transcription factor, a key component of the emergency myelopoiesis triggered by stress and inflammation. Adoptive transfer of tumor antigen-specific CD8+ T lymphocytes resulted in therapy of established tumors only in mice lacking C/EBP in myeloid compartment. These data unveil another link between inflammation and cancer and identify a novel molecular target to control tumor-induced immune suppression.
Tumor-induced tolerance and immune suppression depend on the C/EBPbeta transcription factor.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Modulation of microRNA expression in human T-cell development: targeting of NOTCH3 by miR-150.
No sample metadata fields
View SamplesGene expression of Double Positive, and Single Positive CD4+ human thymocytes
Modulation of microRNA expression in human T-cell development: targeting of NOTCH3 by miR-150.
No sample metadata fields
View SamplesThe effectiveness of new cancer therapies such as checkpoint blockade and adoptive cell transfer of activated anti-tumor T cells requires overcoming immunosuppressive tumor microenvironments. We found that the activation of tumor-infiltrating myeloid cells to produce local nitric oxide is a prerequisite for adoptively transferred CD8+ cytotoxic T cells to destroy tumors. These myeloid cells are phenotypically similar to Tip-DCs or nitric oxide- and TNF-producing dendritic cells. The nitric oxide-dependent killing was tempered by coincident arginase 1 expression, which competes with iNOS for arginine, the substrate for nitric oxide production. Depletion of immunosuppressive CSF-1R-dependent arginase 1+ myeloid cells enhanced nitric oxide-dependent tumor killing. Tumor killing via iNOS was independent of the microbiota but dependent on the CD40-CD40L pathway and, in part, lymphotoxin alpha. We extended our findings in mice to uncover a strong correlation between iNOS, CD40 and TNF expression and survival in colorectal cancer patients. Our results identify a network of anti-tumor targets to boost the efficacy of cancer immunotherapies.
T Cell Cancer Therapy Requires CD40-CD40L Activation of Tumor Necrosis Factor and Inducible Nitric-Oxide-Synthase-Producing Dendritic Cells.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Induced p53 loss in mouse luminal cells causes clonal expansion and development of mammary tumours.
Sex, Specimen part
View Samples