Although a considerable number of reports indicate an involvement of the Hox-A10 gene in the molecular control of hematopoiesis, the conclusions of such studies are quite controversial since they support, in some cases, a role in the stimulation of stem cell self-renewal and myeloid progenitor expansion while, in others, implicate this transcription factor in the induction of monocyte - macrophage differentiation. To clarify this issue we analyzed the biological effects and the transcriptome changes determined in human primary CD34+ hematopoietic progenitors by retroviral transduction of a full length Hox-A10 cDNA. The results obtained clearly indicated that this homeogene is an inducer of monocyte differentiation, at least partly acting through the up-regulation of MafB gene, recently identified as master regulator of such maturation pathway. By using a combined approach based on computational analysis, EMSA experiments and luciferase assays, we were able to demonstrate the presence of a Hox-A10 binding site in the promoter region of the MafB gene, which suggested the likely molecular mechanism underlying the observed effect. Interestingly, stimulation of the same cells with the Vitamin D3 monocyte differentiation inducer resulted in a clear increase of Hox-A10 and MafB transcripts, indicating the existence of a precise transactivation cascade involving VDR, Hox-A10 and MafB transcription factors. Altogether these data allow to conclude that the Vitamin D3 / Hox-A10 pathway supports MafB function during the induction of monocyte differentiation.
The vitamin D3/Hox-A10 pathway supports MafB function during the monocyte differentiation of human CD34+ hemopoietic progenitors.
No sample metadata fields
View SamplesGene expression analysis identified a CRC related signature of differentially expressed genes discriminating patients Responder and Non Responder to radiochemotherapy
A functional biological network centered on XRCC3: a new possible marker of chemoradiotherapy resistance in rectal cancer patients.
Sex, Age, Specimen part, Disease, Disease stage
View SamplesNatural Killer (NK) cells are the first lymphocyte population to reconstitute early after non myelo-ablative and T cell-replete haploidentical hematopoietic stem cell transplantations (h-HSCTs) with post-transplant infusion of cyclophosphamide. The present study characterizes the transient and predominant expansion starting from the 2nd week after h-HSCT of a donor-derived unconventional subset of CD56dim/CD16neg (uCD56dim) NK cells expressing remarkable high levels of NKG2A and low levels of NKp46. Both transcription and phenotypic profiles indicated that uCD56dim NK cells are a distinct NK cell subpopulation with features of late differentiation, yet retaining proliferative capability and functional plasticity to generate conventional CD56bright/CD16pos NK cells in response to IL-15 plus IL-18. uCD56dim NK cells represent by far the largest NK cell subset detectable in the following 7 weeks after h-HSCT and they also express high levels of the activating receptors NKGD and NKp30 as well as of the lytic granules Granzyme-B and Perforin. Nonetheless, uCD56dim NK cells displayed a defective cytotoxicity that could be reversed by blocking the inhibitory receptor CD94/NKG2A. These data open new important perspectives to better understand the ontogenesis/homeostasis of human NK cells and to develop a novel immune-therapeutic approach by targeting the inhibitory NKG2A check point, thus enhancing NK cell alloreactivity early after h-HSCT.
The early expansion of anergic NKG2A<sup>pos</sup>/CD56<sup>dim</sup>/CD16<sup>neg</sup> natural killer represents a therapeutic target in haploidentical hematopoietic stem cell transplantation.
Specimen part
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 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 SamplesWhen grown on solid substrates, different microorganisms often form colonies with very specific morphologies. Whereas the pioneers of microbiology often used colony morphology to discriminate between species and strains, the phenomenon has not received much recent attention. In this study, we use a genome-wide assay in the model yeast Saccharomyces cerevisiae to identify all genes that affect colony morphology. We show that several major signaling cascades, including the MAPK, TORC, SNF1 and RIM101 pathways play a role, indicating that morphological changes are a reaction to changing environments. Other genes that affect colony morphology are involved in protein sorting and epigenetic regulation. Interestingly, the screen reveals only few genes that are likely to play a direct role in establishing colony morphology, one notable exception being FLO11, a gene encoding a cell-surface adhesin that has already been implicated in colony morphology, biofilm formation, and invasive and pseudohyphal growth. Using a series of modified promoters to tune FLO11 expression, we confirm the central role of Flo11 and show that differences in FLO11 expression result in distinct colony morphologies. Together, our results provide a first comprehensive looks at the complex genetic network that underlies the diversity in the morphologies of yeast colonies.
Identification of a complex genetic network underlying Saccharomyces cerevisiae colony morphology.
No sample metadata fields
View SamplesProliferation of neoplastic plasma cells within the bone marrow leads to reduced oxygen availability. In response to hypoxia, the transcription factor hypoxia-inducible factor-2alpha (HIF-2) is activated and stabilised. We hypothesise that activation of HIF-2 is a central driver of multiple myeloma disease progression, leading to the induction of transcription of genes associated with angiogenesis, osteoclast activation and cell migration. In this study we assessed the affects of HIF-2 overexpression on gene expression in the human myeloma cell line LP-1.
HIF-2α Promotes Dissemination of Plasma Cells in Multiple Myeloma by Regulating CXCL12/CXCR4 and CCR1.
No sample metadata fields
View SamplesCD103+CD11b+ dendritic cells (DC) are unique to the intestine, but the factors governing their differentiation are unclear. Here we show that transforming growth factor receptor 1 (TGF beta 1) has an indispensable, cell intrinsic role in the development of these cells. Deletion of Tgfbr1 results in markedly fewer intestinal CD103+CD11b+ DCs and a reciprocal increase in the CD103CD11b+ DC subset. Transcriptional profiling identifies markers that define the CD103+CD11b+ DC lineage, including CD101, TREM1 and Siglec-F, and shows that the absence of CD103+CD11b+ DCs in CD11c-Cre.Tgfbr1fl/fl mice reflects defective differentiation from CD103CD11b+ intermediaries, rather than an isolated loss of CD103 expression. The defect in CD103+CD11b+ DCs is accompanied by reduced generation of antigen-specific, inducible FoxP3+ regulatory T (Treg) cells in vitro and in vivo, and by reduced numbers of endogenous TH17 cells in the intestinal mucosa. Thus, TGF beta 1 mediated signalling may explain the tissue-specific development of these unique DCs.
TGFβR signalling controls CD103<sup>+</sup>CD11b<sup>+</sup> dendritic cell development in the intestine.
Specimen part
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