Abstract 2719: Aberrant expression of transcription factors STAT-3 and STAT-5 and their epigenetic control by SOCS-1 gene: The STAT signaling crosstalk in HPV coupled cervical carcinogenesis

Because it accounts for 70% of all eye cancers, uveal melanoma (UM) is therefore the most common primary ocular malignancy. In this study, we investigated the molecular mechanisms leading to the aberrant expression of the gene encoding the serotonin receptor 2B (HTR2B), one of the most discriminating among the candidates from the class II gene signature, in metastatic and non-metastatic UM cell lines. Transfection analyses revealed that the upstream regulatory region of the HTR2B gene contains a combination of alternative positive and negative regulatory elements functional in HTR2B− but not in HTR23B+ UM cells. We demonstrated that both the transcription factors nuclear factor I (NFI) and Runt-related transcription factor I (RUNX1) interact with regulatory elements from the HTR2B gene to either activate (NFI) or repress (RUNX1) HTR2B expression in UM cells. The results of this study will help understand better the molecular mechanisms accounting for the abnormal expression of the HTR2B gene in uveal melanoma.

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β2 integrin–derived signals induce cell survival and proliferation of AML blasts by activating a Syk/STAT signaling axis

Blood ◽

10.1182/blood-2012-09-457887 ◽

2013 ◽

Vol 121 (19) ◽

pp. 3889-3899 ◽

Cited By ~ 32

Author(s):

Thomas Oellerich ◽

Mark F. Oellerich ◽

Michael Engelke ◽

Silvia Münch ◽

Sebastian Mohr ◽

...

Keyword(s):

Transcription Factors ◽

Cell Survival ◽

Integrin Signaling ◽

Β2 Integrin ◽

Key Points ◽

Stat Signaling ◽

Signaling Axis ◽

Cell Survival And Proliferation

Key Points Integrin signaling promotes proliferative signals in AML cells that are mediated by the kinase Syk and the transcription factors STAT3 and STAT5.

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Human erythroleukemia genetics and transcriptomes identify master transcription factors as functional disease drivers

Blood ◽

10.1182/blood.2019003062 ◽

2020 ◽

Vol 136 (6) ◽

pp. 698-714 ◽

Cited By ~ 5

Author(s):

Alexandre Fagnan ◽

Frederik Otzen Bagger ◽

Maria-Riera Piqué-Borràs ◽

Cathy Ignacimouttou ◽

Alexis Caulier ◽

...

Keyword(s):

Transcription Factors ◽

Molecular Mechanisms ◽

Hematologic Malignancy ◽

Ectopic Expression ◽

Leukemic Cells ◽

Erythroid Progenitors ◽

Molecular Subgroup ◽

Aberrant Expression ◽

In Vivo Models ◽

Hematopoietic Stem

Abstract Acute erythroleukemia (AEL or acute myeloid leukemia [AML]-M6) is a rare but aggressive hematologic malignancy. Previous studies showed that AEL leukemic cells often carry complex karyotypes and mutations in known AML-associated oncogenes. To better define the underlying molecular mechanisms driving the erythroid phenotype, we studied a series of 33 AEL samples representing 3 genetic AEL subgroups including TP53-mutated, epigenetic regulator-mutated (eg, DNMT3A, TET2, or IDH2), and undefined cases with low mutational burden. We established an erythroid vs myeloid transcriptome-based space in which, independently of the molecular subgroup, the majority of the AEL samples exhibited a unique mapping different from both non-M6 AML and myelodysplastic syndrome samples. Notably, >25% of AEL patients, including in the genetically undefined subgroup, showed aberrant expression of key transcriptional regulators, including SKI, ERG, and ETO2. Ectopic expression of these factors in murine erythroid progenitors blocked in vitro erythroid differentiation and led to immortalization associated with decreased chromatin accessibility at GATA1-binding sites and functional interference with GATA1 activity. In vivo models showed development of lethal erythroid, mixed erythroid/myeloid, or other malignancies depending on the cell population in which AEL-associated alterations were expressed. Collectively, our data indicate that AEL is a molecularly heterogeneous disease with an erythroid identity that results in part from the aberrant activity of key erythroid transcription factors in hematopoietic stem or progenitor cells.

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MiR-132 and MiR-212 as Regulators of WT1 and GATA2 in Acute Myeloid Leukemia.

Blood ◽

10.1182/blood.v114.22.1283.1283 ◽

2009 ◽

Vol 114 (22) ◽

pp. 1283-1283 ◽

Cited By ~ 1

Author(s):

Maaike Luesink ◽

Jeannet Nigten ◽

Ruth H.J.N. Knops ◽

Theo J.M. de Witte ◽

Bert A. van der Reijden ◽

...

Keyword(s):

Gene Expression ◽

Acute Myeloid Leukemia ◽

Transcription Factors ◽

Quantitative Pcr ◽

Blood Cells ◽

Myeloid Leukemia ◽

Granulocytic Differentiation ◽

Aberrant Expression ◽

Differentiation Induction ◽

Acute Myeloid

Abstract Abstract 1283 Poster Board I-305 Wilms' tumor 1 (WT1) and GATA binding protein 2 (GATA2) transcription factors are highly expressed in hematopoietic stem cells and progenitors. Differentiation of precursor blood cells towards mature blood cells is accompanied by rapid downregulation of both transcription factors. Overexpression of WT1 has been observed in the majority of acute myeloid leukemia (AML) cases. Furthermore, in 10-15% of the AML cases mutations in the WT1 gene occur, which have been correlated with poor prognosis. Aberrant expression of GATA2 in AML has been described as well, but no mutations in this gene have been reported in AML so far. How the (aberrant) expression of WT1 and GATA2 is controlled is not completely clear. A regulatory role for microRNAs (miRNAs) has been described for several transcription factors which regulate hematopoiesis. MiRNAs negatively regulate gene expression by translational repression or degradation of target messenger RNAs (mRNAs). In the present study we investigated the interplay between miRNAs and transcription factors that are involved in myeloid development and malignant transformation towards AML. We studied the expression of 158 miRNAs in the APL cell line NB4 during induction of granulocytic differentiation with all-trans retinoic acid (ATRA). Quantitative PCR specific for mature miRNAs was performed (Applied Biosystems). Twenty out of 158 miRNAs were more than 10-fold upregulated upon differentiation induction with ATRA. MiR-132 and miR212, which are derived from the same pri-miRNA transcript, were most strongly upregulated during ATRA-induced granulocytic differentiation (1200- and 350-fold respectively at 96 hours after ATRA-stimulation). In vitro ATRA-induction of primary APL cells also resulted in upregulation of miR-132 and miR-212. Computational target prediction algorithms were used to identify transcription factors which may be targeted by miR-132 and miR-212. Subsequently, the expression pattern of the predicted targets was determined experimentally in NB4 cells before and after differentiation induction with ATRA using microarray-based mRNA profiling (Affymetrix). In addition, further verification of target gene expression during ATRA-induced differentiation was performed using quantitative PCR. The transcription factors WT1 and GATA2 were predicted as targets of miR-132 and miR-212 by two out of four different prediction programs that were used. Both transcription factors contained putative binding sites for miR-132 and miR-212 in their 3'UTR. When tested on microarray and by quantitative PCR, the expression of WT1 and GATA2 was indeed strongly downregulated during ATRA-induced granulocytic differentiation of NB4 cells (65- and 165-fold respectively at 96 hours after ATRA stimulation) as well as in primary leukemia cells derived from APL patients (30- and 10-fold respectively at 48 hours after ATRA-stimulation). During ATRA-induced differentiation the expression levels of WT1 were positively correlated with the expression levels of GATA2. In addition, WT1 expression was also strongly correlated with GATA2 expression in a cohort of 27 pre-treatment AML cases as well as in 7 healthy controls, suggesting that these genes might be co-regulated to a large extent. To directly prove that WT1 and GATA2 are indeed targeted by miR-132 and miR-212, we are currently performing lentiviral-based overexpression studies of both miRNAs to determine the effect on endogenous WT1 and GATA2 mRNA expression. MicroRNAs which target WT1 and GATA2 may be valuable tools in controlling the aberrant expression of WT1 and GATA2 observed in AML. Disclosures No relevant conflicts of interest to declare.

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EZH2 knockdown upregulates expression of the genes involved in T-ALL cell differentiation

Pharmaceutical Sciences ◽

10.34172/ps.2021.56 ◽

2021 ◽

Author(s):

Sahar Safaei ◽

Behzad Baradaran ◽

Behzad Mansoori ◽

Masoumeh Fardi ◽

Elham Baghbani ◽

...

Keyword(s):

T Cells ◽

Transcription Factors ◽

Cell Differentiation ◽

T Cell ◽

Lymphoblastic Leukemia ◽

Leukemia Cell ◽

Leukemia Cell Line ◽

Aberrant Expression ◽

Expression Levels ◽

Ezh2 Expression

Background: EZH2 (enhancer of zeste 2 polycomb repressive complex 2 subunit), as one of the polycyclic group proteins (PcGs), is an epigenetic regulator that plays a crucial role in the pathophysiology of hematologic malignancies through regulating cell differentiation. Also, it is well known that aberrant expression of specific transcription factors can be involved in the pathogenesis of various cancers. Objective: Herein, we aimed to suppress EZH2 expression in MOLT-4 cells, T-ALL (T cell acute lymphoblastic leukemia) cell line, and evaluate the role of EZH2 on the expression of transcription factors that regulate T cell maturation, differentiation, and apoptosis. Methods: EZH2-siRNA was transfected into MOLT-4 cells, and the expression levels of EZH2, NOTCH1, TCF1, IKZF1, and NFATC1 were measured using real-time PCR. The MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay was performed to study the effect of EZH2 knockdown on MOLT-4 cell viability. The apoptosis rate of EZH2-siRNA transfected cells was assessed by flow cytometry. The interaction of mentioned genes was investigated using STRING and GO (gene ontology). Results: Our results have shown that EZH2-siRNA transfection can substantially decrease EZH2 expression in MOLT-4 cells. Besides, EZH2 suppression can upregulate NOTCH1, TCF1, IKZF1, and NFATC1 expression levels. EZH2 knockdown does not affect the viability and apoptosis of MOLT-4 cells. The most remarkable protein-protein interaction of EZH2 has been with NOTCH1. Besides, GO analysis has demonstrated that EZH2, NOTCH1, TCF1, IKZF1, and NFATC1 were located within nucleoplasm and can regulate RNA polymerase II-mediated transcription. Conclusion: Our results have shown that MOLT-4 cells harbor increased expression of EZH2 in comparison with normal human T cells. EZH2 knockdown can upregulate the expression of the transcription factors involved in T cell differentiation. Thus, EZH2 can halt the differentiation of immature lymphoblastic T cells.

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Forkhead (Fox) transcription factors open a new dimension in understanding the epigenetic control of replication origins in S. cerevisiae

The FASEB Journal ◽

10.1096/fasebj.27.1_supplement.200.1 ◽

2013 ◽

Vol 27 (S1) ◽

Author(s):

Oscar Aparicio ◽

Simon R. V. Knott ◽

Zachary A. Ostrow ◽

Jared M. Peace ◽

Yan Gan ◽

...

Keyword(s):

Transcription Factors ◽

Replication Origins ◽

Epigenetic Control

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The roles of JAK/STATs and transcription factors in the framework of host immunological pathways

10.31219/osf.io/qgcwb ◽

2021 ◽

Author(s):

Wan-Chung Hu

Keyword(s):

Immune Response ◽

Transcription Factors ◽

Specific Immune Response ◽

Stat Signaling

Transcription factors, especially STATs proteins, play vital roles in the host immunological pathways. These STATs proteins compete each other and drive different immunological pathways in reaction to different pathogens. Here, I summarize the JAK-STAT signaling for each immunological pathway. In addition, specific important transcription factors for specific immune response are also given. Tfh is related to STAT5 and BCL6. Treg is related to STAT5a, STAT5b, and FOXP3. TH1 immunity is related to STAT1a, STAT4, and T-bet. TH2a immunity is related to STAT6, STAT1a, GATA1, and GATA3. TH2b immunity is related to STAT6, STAT3, GATA2, and GATA3. TH22 immunity is related to STAT3 and AHR. THab immunity is related to STAT1a, STAT1b, STAT2, STAT3b, and ISGF. TH1-like immunity is related to STAT1a, STAT4, STAT5a, and STAT5b. TH9 immunity is related to STAT6, STAT5a, STAT5b, and PU.1. TH17 immunity is related to STAT3a, STAT5a, STAT5b and RORG. TH3 immunity is related to STAT1a, STAT1b, STAT2, STAT3b, STAT5a, STAT5b, and ISGF.

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PU.1 and Spi-B Oppose Transformation Of Pre-B Cells Through Activation Of Key Genes Involved In B Cell Receptor Signalling

Blood ◽

10.1182/blood.v122.21.3737.3737 ◽

2013 ◽

Vol 122 (21) ◽

pp. 3737-3737

Author(s):

Darah A. Christie ◽

Shereen A. Turkistany ◽

Li S. Xu ◽

Stephen K. H. Li ◽

Ian Welch ◽

...

Keyword(s):

Bone Marrow ◽

Transcription Factors ◽

B Cells ◽

B Cell ◽

Cell Receptor ◽

B Cell Receptor ◽

Cell Phenotype ◽

Aberrant Expression ◽

Receptor Signalling ◽

Key Genes

Abstract B cell development is controlled by stage-specific expression of transcription factors. Aberrant expression of such factors can lead to B cell acute lymphoblastic leukemia (B-ALL). Deletion of genes encoding the E26 transformation-specific (ETS) transcription factors, PU.1 and Spi-B, in B cells (CD19+/CreSfpi1lox/loxSpib-/- mice, abbreviated to CD19-CreΔPB) leads to B-ALL at 100% incidence and with a median survival of 21 weeks. However, little is known about the target genes of PU.1 and Spi-B that explain leukemic transformation in these mice. In the current study, we investigated the developmental origins and mechanisms of leukemogenesis in CD19-CreΔPB mice. We found that B-ALL cells in CD19-CreΔPB mice had frequently rearranged both their heavy and light chain genes, but retained cell surface expression of interleukin-7 receptor (IL-7R), suggesting aberrant pre-B cell differentiation. Preleukemic CD19-CreΔPB mice had increased frequencies of pre-B cells compared to wild type mice. Pre-B cells, but not mature B cells, purified from the bone marrow of preleukemic CD19-CreΔPB mice could rapidly transfer disease to transplanted recipient mice. B-ALL cells from established tumors had uniform expression of markers indicating a pre-B cell phenotype and contained a high-frequency of leukemia-initiating cells as measured by transplantation assays. Genome-wide analysis of gene expression showed that B cell receptor signalling was the top impaired pathway in B-ALL cells from CD19-CreΔPB mice. Bone marrow cells from CD19-CreΔPB mice had increased responsiveness to IL-7R signalling and could be cultured as IL-7-dependent cell lines. Preleukemic or leukemic cells from CD19-CreΔPB mice expressed reduced levels of the gene encoding Bruton’s tyrosine kinase (Btk), which we show is a target gene of PU.1 and/or Spi-B that in combination with reduced BLNK is sufficient to explain increased IL-7R responsiveness. We conclude that mutation of PU.1 and Spi-B predispose developing B cells to leukemogenesis by impairing expression of key genes, such as Btk, that are required for BCR signalling and are involved in attenuation of IL-7 receptor signaling. Disclosures: No relevant conflicts of interest to declare.

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Augmenting E Protein Activity Impairs cDC2 Differentiation at the Pre-cDC Stage

Frontiers in Immunology ◽

10.3389/fimmu.2020.577718 ◽

2020 ◽

Vol 11 ◽

Author(s):

Sandra Bajana ◽

Kevin Thomas ◽

Constantin Georgescu ◽

Ying Zhao ◽

Jonathan D. Wren ◽

...

Keyword(s):

Transcription Factors ◽

Protein Function ◽

Loss Of Function ◽

Protein Activity ◽

E Proteins ◽

Aberrant Expression ◽

Precise Control ◽

Helix Loop Helix ◽

Id Proteins ◽

E Protein

Dendritic cell (DC) specification and differentiation are controlled by a circuit of transcription factors, which regulate the expression of DC effector genes as well as the transcription factors themselves. E proteins are a widely expressed basic helix-loop-helix family of transcription factors whose activity is suppressed by their inhibitors, ID proteins. Loss-of-function studies have demonstrated the essential role of both E and ID proteins in different aspects of DC development. In this study, we employed a gain-of-function approach to illustrate the importance of the temporal control of E protein function in maintaining balanced differentiation of conventional DC (cDC) subsets, cDC1 and cDC2. We expressed an E protein mutant, ET2, which dimerizes with endogenous E proteins to overcome inhibition by ID proteins and activate the transcription of E protein targets. Induction of ET2 expression at the hematopoietic progenitor stage led to a dramatic reduction in cDC2 precursors (pre-cDC2s) with little impact on pre-cDC1s. Consequently, we observed decreased numbers of cDC2s in the spleen and lung, as well as in FLT3L-driven bone marrow-derived DC cultures. Furthermore, in mice bearing ET2, we detected increased expression of the IRF8 transcription factor in cDC2s, in which IRF8 is normally down-regulated and IRF4 up-regulated. This aberrant expression of IRF8 induced by ET2 may contribute to the impairment of cDC2 differentiation. In addition, analyses of the transcriptomes of splenic cDC1s and cDC2s revealed that ET2 expression led to a shift, at least in part, of the transcriptional profile characteristic of cDC2s to that of cDC1. Together, these results suggest that a precise control of E protein activity is crucial for balanced DC differentiation.

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