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Aims: Glucagon-like peptide-1 receptor agonists are effective treatments for type 2 diabetes, effectively lowering glucose without weight gain and with low risk for hypoglycemia. However, their influence on the retinal neurovascular unit remains unclear. In this study, we analyzed the effects of the GLP-1 RA lixisenatide on diabetic retinopathy. Methods: Vasculo- and neuroprotective effects were assessed in experimental diabetic retinopathy and high glucose-cultivated C. elegans, respectively. In STZ-diabetic Wistar rats, acellular capillaries and pericytes (quantitative retinal morphometry), neuroretinal function (mfERG), macroglia (GFAP western blot) and microglia (immunohistochemistry) quantification, methylglyoxal (LC–MS/MS) and retinal gene expressions (RNA-sequencing) were determined. The antioxidant properties of lixisenatide were tested in C. elegans. Results: Lixisenatide had no effect on glucose metabolism. Lixisenatide preserved the retinal vasculature and neuroretinal function. The macro- and microglial activation was mitigated. Lixisenatide normalized some gene expression changes in diabetic animals to control levels. Ets2 was identified as a regulator of inflammatory genes. In C. elegans, lixisenatide showed the antioxidative property. Conclusions: Our data suggest that lixisenatide has a protective effect on the diabetic retina, most likely due to a combination of neuroprotective, anti-inflammatory and antioxidative effects of lixisenatide on the neurovascular unit. [ABSTRACT FROM AUTHOR]

ETS2 is a member of the ETS family of transcription factors and has been implicated in the regulation of cell proliferation, differentiation, apoptosis, and tumorigenesis. The aberrant activation of ETS2 is associated with various human cancers, highlighting its importance as a therapeutic target. Understanding the regulatory mechanisms and interacting partners of ETS2 is crucial for elucidating its precise role in cellular processes and developing novel strategies to modulate its activity. In this study, we conducted binding assays using a human deubiquitinase (DUB) library and identified USP39 as a novel ETS2-binding DUB. USP39 interacts with ETS2 through their respective amino-terminal regions, and the zinc finger and PNT domains are not required for this binding. USP39 deubiquitinates ETS2 without affecting its protein stability. Interestingly, however, USP39 significantly suppresses the transcriptional activity of ETS2. Furthermore, we demonstrated that USP39 leads to a reduction in the nuclear localization of ETS2. Our findings provide valuable insights into the intricate regulatory mechanisms governing ETS2 function. Understanding the interplay between USP39 and ETS2 may have implications for therapeutic interventions targeting ETS2-related diseases, including cancer, where the dysregulation of ETS2 is frequently observed. [ABSTRACT FROM AUTHOR]

This article analyzes the recently decided EU-wide emission trading scheme for road transport and heating fuels. The so-called ETS2 is part of the 'Fit for 55' policy package, which also includes tighter vehicle emission standards, a reform of energy taxation, provisions to enhance advanced fuel infrastructure and a Social Climate Fund to alleviate financial pressure for low-income households. We argue that the ETS2 should be understood as an element of a broader policy mix, which considers multiple market failures, fairness both within and across EU member states within the institutional constraints of EU policy making. We conclude by discussing specific potential modifications to the design of the ETS2 that could help achieve the EU's climate target in an efficient and equitable way. These include linking ETS and ETS2, reducing price volatility, increasing the size of the Social Climate fund, and clarifying penalties for countries missing targets under the Effort Sharing Regulation. • Various measures complement EU carbon pricing in heating and transport. • Distributional concerns, within and across countries, are key to policy design. • Various measures aim to ensure prices in ETS2 remain limited. • Continued inclusion of ETS2-sectors in ESR ensures rich EU countries must mitigate. • We propose further evolution of ETS, including linking, price corridors, larger SCF. Highlights: Political and economic analysis of the policy mix to decarbonize road transport with a special focus on the role of the recently decided new emissions trading scheme for this sector. [ABSTRACT FROM AUTHOR]

Heart failure (HF) is a chronic disease in which the heart is unable to provide enough blood and oxygen to the peripheral tissues. Cardiomyocyte apoptosis and autophagy have been linked to HF progression. However, the underlying mechanism of HF is unknown. In this study, H2O2‐treated AC16 cells were used as a cell model of HF. The mRNA and protein levels of related genes were examined using RT‐qPCR and western blot. Cell viability and apoptosis were assessed using CCK‐8 and flow cytometry, respectively. The interactions between ETS2, TUG1, miR‐129‐5p, and ATG7 were validated by luciferase activity, ChIP, and RNA‐Binding protein Immunoprecipitation assays. According to our findings, H2O2 stimulation increased the expression of ETS2, TUG1, and ATG7 while decreasing the expression of miR‐129‐5p in AC16 cells. Furthermore, H2O2 stimulation induced cardiomyocyte apoptosis and autophagy, which were reversed by ETS2 depletion, TUG1 silencing, or miR‐129‐5p upregulation. Mechanistically, ETS2 promoted TUG1 expression by binding to the TUG1 promoter, and TUG1 sponged miR‐129‐5p to increase ATG7 expression. Furthermore, TUG1 overexpression reversed ETS2 knockdown‐mediated inhibition of cardiomyocyte apoptosis and autophagy and miR‐129‐5p inhibition abolished TUG1 depletion‐mediated suppression of cardiomyocyte apoptosis and autophagy in H2O2‐induced AC16 cells. As presumed, ATG7 overexpression reversed miR‐129‐5p mimics‐mediated repression of cardiomyocyte apoptosis and autophagy in H2O2‐induced AC16 cells. Finally, ETS2 silencing reduced cardiomyocyte apoptosis and autophagy to slow HF progression by targeting the ETS2/TUG1/miR‐129‐5p/ATG7 axis, which may provide new therapeutic targets for HF treatment. [ABSTRACT FROM AUTHOR]

An inverse comorbidity has been observed between Down syndrome (DS) and solid tumors such as breast and lung cancers, and it is posited that the overexpression of genes within the Down Syndrome Critical Region (DSCR) of human chromosome 21 may account for this phenomenon. By analyzing publicly available DS mouse model transcriptomics data, we aimed to identify DSCR genes that may protect against human breast and lung cancers. Gene expression analyses with GEPIA2 and UALCAN showed that DSCR genes ETS2 and RCAN1 are significantly downregulated in breast and lung cancers, and their expression levels are higher in triple-negative compared to luminal and HER2-positive breast cancers. KM Plotter showed that low levels of ETS2 and RCAN1 are associated with poor survival outcomes in breast and lung cancers. Correlation analyses using OncoDB revealed that both genes are positively correlated in breast and lung cancers, suggesting that they are co-expressed and perhaps have complementary functions. Functional enrichment analyses using LinkedOmics also demonstrated that ETS2 and RCAN1 expression correlates with T-cell receptor signaling, regulation of immunological synapses, TGF-β signaling, EGFR signaling, IFN-γ signaling, TNF signaling, angiogenesis, and the p53 pathway. Altogether, ETS2 and RCAN1 may be essential for the development of breast and lung cancers. Experimental validation of their biological functions may further unravel their roles in DS and breast and lung cancers. [ABSTRACT FROM AUTHOR]

Hepatitis B virus‐related acute‐on‐chronic liver failure (HBV‐ACLF) is a syndrome with high short‐term mortality. The mechanism of the transcription factor ETS2 in ACLF remains unclear. This study aimed to clarify the molecular basis of ETS2 in ACLF pathogenesis. Peripheral blood mononuclear cells from patients with HBV‐ACLF (n = 50) were subjected to RNA sequencing. Transcriptome analysis showed that ETS2 expression was significantly higher in ACLF patients than in patients with chronic liver diseases and healthy subjects (all p < 0.001). Area‐under‐ROC analysis of ETS2 demonstrated high values for the prediction of 28‐/90‐day mortality in ACLF patients (0.908/0.773). Significantly upregulated signatures of the innate immune response (monocytes/neutrophils/inflammation‐related pathways) were observed in ACLF patients with high ETS2 expression. Myeloid‐specific ETS2 deficiency in liver failure mice resulted in deterioration of biofunctions and increased expression of pro‐inflammatory cytokines (IL‐6/IL‐1β/TNF‐α). Knockout of ETS2 in macrophages confirmed the downregulation of IL‐6 and IL‐1β caused by both HMGB1 and lipopolysaccharide, and an NF‐κB inhibitor reversed the suppressive effect of ETS2. ETS2 is a potential prognostic biomarker of ACLF patients that alleviates liver failure by downregulating the HMGB1‐/lipopolysaccharide‐triggered inflammatory response and may serve as a therapeutic target for ACLF. [ABSTRACT FROM AUTHOR]

E26 transformation specific or E twenty-six (ETS) protein family consists of 28 transcription factors, five of which, named ETS1/2, PU.1, ERG and EHF, are known to involve in the development of liver fibrosis, and are expected to become diagnostic markers or therapeutic targets of liver fibrosis. In recent years, some small molecule inhibitors of ETS protein family have been discovered, which might open up a new path for the liver fibrosis therapy targeting ETS. This article reviews the research progress of ETS family members in the development liver fibrosis as well as their prospect of clinical application. [ABSTRACT FROM AUTHOR]

ETS2 is a member of the ETS family of transcription factors and has been implicated in the regulation of cell proliferation, differentiation, apoptosis, and tumorigenesis. The aberrant activation of ETS2 is associated with various human cancers, highlighting its importance as a therapeutic target. Understanding the regulatory mechanisms and interacting partners of ETS2 is crucial for elucidating its precise role in cellular processes and developing novel strategies to modulate its activity. In this study, we conducted binding assays using a human deubiquitinase (DUB) library and identified USP39 as a novel ETS2-binding DUB. USP39 interacts with ETS2 through their respective amino-terminal regions, and the zinc finger and PNT domains are not required for this binding. USP39 deubiquitinates ETS2 without affecting its protein stability. Interestingly, however, USP39 significantly suppresses the transcriptional activity of ETS2. Furthermore, we demonstrated that USP39 leads to a reduction in the nuclear localization of ETS2. Our findings provide valuable insights into the intricate regulatory mechanisms governing ETS2 function. Understanding the interplay between USP39 and ETS2 may have implications for therapeutic interventions targeting ETS2-related diseases, including cancer, where the dysregulation of ETS2 is frequently observed.

BackgroundMembranous nephropathy (MN) is a common pathological phenotype for adult nephrotic syndrome (NS). The occurrence of MN is increasing across China, but diagnostic methods for MN still rely on kidney biopsy and PLA2R and THSD7A detection in plasma and kidney tissue, and there has been no new biomarker for MN discovered since 2014. Immune infiltration status in MN patients suffers from the dearth of associated studies. In the present study, we aimed to find new bio-markers for MN and evaluate the role of immune cells infiltration in MN pathology.MethodsWe downloaded MN expression profile from the Gene Expression Omnibus database and used R-project to screen differentially expressed genes (DEGs) and performed functional correlation analysis. Least absolute shrinkage and selection operator (LASSO) logistic regression and Radom Forest algorithms were used to screen and verify the bio-markers of MN. Finally, CIBERSORT was used to evaluate the infiltration of immune cells in MN tissues.ResultsA total of 463 DEGs were screened from the MN tissue in this study. ETS2 was identified as bio-marker for MN. The CIBERSORT results showed that there were statistical differences in monocytes, plasma cells, regulatory T cells, and memory B cells. In addition, ETS2 was positively related to monocytes, M1 phase macrophages, and neutrophils and negatively correlated to plasma cells, CD4+ T memory cells, M2 macrophages, CD8+ T cells, memory B cells, and resting mast cells.Conclusion(1) Machine learning algorithms reveals Ets2 as a novel target for membranous nephropathy patients. (2) Immune infiltration plays an important part in membranous nephropathy. (3) Ets2 expression is related to immune cells infiltration.

Background: Cardiac hypertrophy is an independent risk factor for heart failure, a leading cause of morbidity and mortality globally. The calcineurin/NFAT (nuclear factor of activated T cells) pathway and the MAPK (mitogen-activated protein kinase)/Erk (extracellular signal-regulated kinase) pathway contribute to the pathogenesis of cardiac hypertrophy as an interdependent network of signaling cascades. How these pathways interact remains unclear and few direct targets responsible for the prohypertrophic role of NFAT have been described.Methods: By engineering cardiomyocyte-specific ETS2 (a member of the E26 transformation-specific sequence [ETS] domain family) knockout mice, we investigated the role of ETS2 in cardiac hypertrophy. Primary cardiomyocytes were used to evaluate ETS2 function in cell growth.Results: ETS2 is phosphorylated and activated by Erk1/2 on hypertrophic stimulation in both mouse (n=3) and human heart samples (n=8 to 19). Conditional deletion of ETS2 in mouse cardiomyocytes protects against pressure overload-induced cardiac hypertrophy (n=6 to 11). Silencing of ETS2 in the hearts of calcineurin transgenic mice significantly attenuates hypertrophic growth and contractile dysfunction (n=8). As a transcription factor, ETS2 is capable of binding to the promoters of hypertrophic marker genes, such as ANP, BNP, and Rcan1.4 (n=4). We report that ETS2 forms a complex with NFAT to stimulate transcriptional activity through increased NFAT binding to the promoters of at least 2 hypertrophy-stimulated genes: Rcan1.4 and microRNA-223 (=n4 to 6). Suppression of microRNA-223 in cardiomyocytes inhibits calcineurin-mediated cardiac hypertrophy (n=6), revealing microRNA-223 as a novel prohypertrophic target of the calcineurin/NFAT and Erk1/2-ETS2 pathways.Conclusions: Our findings point to a critical role for ETS2 in calcineurin/NFAT pathway-driven cardiac hypertrophy and unveil a previously unknown molecular connection between the Erk1/2 activation of ETS2 and expression of NFAT/ETS2 target genes. [ABSTRACT FROM AUTHOR]

Lena Heinbockel,1,2 Sebastian Marwitz,1,2 Andra B Schromm,3 Henrik Watz,2,4 Christian Kugler,2,5 Ole Ammerpohl,2,6 Karoline Schnepf,7 Klaus F Rabe,2,5 Daniel Droemann,2,7 Torsten Goldmann1,2 1Pathology of the University Medical Center Schleswig-Holstein (UKSH), Campus Luebeck and Research Center Borstel, Borstel, Germany; 2Airway Research Center North (ARCN), German Center for Lung Research (DZL), Großhansdorf, Germany; 3Immunobiophysics, Research Center Borstel, Borstel, Germany; 4Pulmonary Research Institute at LungenClinic Grosshansdorf, Grosshansdorf, Germany; 5LungenClinic Grosshansdorf, Grosshansdorf, Germany; 6Institute of Human Genetics, University Medical Center Ulm, Ulm, Germany; 7Medical Clinic III, Pulmonology/Infectious Diseases, University Hospital Schleswig-Holstein, Campus Luebeck, Luebeck, Germany Introduction: As part of a study aimed at illuminating at least some of the complex molecular events taking place in COPD, we screened tissues by means of transcriptome analyses. Materials and methods: Tissues were subjected to transcriptome analysis. Candidate genes were identified and validated by immunohistochemistry. Primary human lung cells were subjected to stimulation with cigarette smoke extract for further validation by real time PCR. Results: Six candidate genes were selected for further investigations: Aquaporin 3 (AQP3), extracellular matrix protein 1 (ECM1), four and a half LIM domain 1 (FHL1), milk fat globule epidermal growth factor 8 (MFGE8, lactadherin), phosphodiesterase 4D-interacting protein (PDE4DIP), and creatine transporter SLC6A8. All six proteins were allocated to distinct cell types by immunohistochemistry. Upon stimulation with cigarette smoke extract, human type II pneumocytes showed a dose-dependent down-regulation of MFGE8, while ECM1 and FHL1 also tended to be down-regulated. Although present, none of the candidates was regulated by cigarette smoke extract in primary human macrophages. Discussion: MFGE8 turned out to be an interesting new candidate gene in COPD deserving further studies. Keywords: COPD, transcriptome, MFGE8, CSE, cigarette smoke extract, ETS2

Transcription factor ETS2 regulates genes involved in development, differentiation, angiogenesis, proliferation, and apoptosis. In addition, it is one of the core reprogramming factors responsible for the generation of human cardiomyocytes from adult somatic cells. In this study, we report the heterologous expression of human ETS2 in E. coli to produce a highly pure recombinant protein. To accomplish this, the codon-optimized 1507 bp coding sequence of the human ETS2 gene in fusion with a His-tag, a cell-penetrating peptide, and a nuclear localization sequence was cloned in the protein expression vector and transformed into E. coli strain BL21(DE3) for expression. The recombinant protein was purified to homogeneity under native conditions using immobilized metal ion affinity chromatography, and its identity was confirmed by Western blotting with an ETS2 antibody. Using far-UV circular dichroism spectroscopy, we have demonstrated that the recombinant protein has retained its secondary structure, predominantly comprising of random coils and β-sheets. Prospectively, this biological recombinant ETS2 protein can substitute viral and genetic forms of ETS2 in a cell reprogramming process to facilitate the generation of clinical-grade cells. It can also be used to investigate its molecular role in various biological processes and diseases and for biochemical and structural studies. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is the most common irreversible chronic joint dysfunction disease, which is pathologically characterized by disturbance of articular cartilage homeostasis leading to subsequent inflammatory response and cartilage extracellular matrix (ECM) degradation. Increasing evidence has demonstrated the dysregulation of transcription factors play crucial roles in the occurrence and development of osteoarthritis (OA), but the potential functions and mechanism of most transcription factors in OA has not been completely illuminated. In this study, we identified that transcription factor V-ets erythroblastosis virus E26 oncogene homolog 2 (ETS2) was significantly down-regulated in OA cartilage and IL-1β-induced OA chondrocytes. Functional experiments in vitro demonstrated that the overexpressed ETS2 strikingly enhanced proliferation, outstandingly suppressed apoptosis, and dramatically reduced inflammation and ECM degradation in IL-1β-induced OA chondrocytes, whereas the knockdown of ETS2 led to the opposite effects. Further in vivo studies have shown that up-regulated ETS2 dramatically ameliorates cartilage injury in DMM-induced OA mice. Mechanical studies have disclosed that DNMT1-mediated downregulation of ETS2 dramatically promotes STAT1 by inhibiting miR-155 transcription, and increased STAT1 initiates a feedback loop that may enhance DNMT1-mediated hypermethylation of ETS2 to inhibit ETS2 expression, thus forming a DNMT1/ETS2/miR-155/STAT1 feedback loop that inhibits MAPK signaling pathways and aggravates OA cartilage injury. In all, our results revealed that overexpression of ETS2 markedly ameliorated OA cartilage injury through the ETS2/miR-155/STAT1/DNMT1 feedback loop, providing a new perspective on the pathogenesis and therapeutic strategies for OA. • ETS2 regulated by DNMT1 was downregulated in OA cartilage tissue and chondrocytes. • ETS2 overexpression ameliorated OA cartilage injury in vitro and in vivo. • ETS2 alleviated OA cartilage injury by promoting miR-155 expression and inhibiting STAT1-MAPK signaling pathway. • ETS2 regulated DNMT1expression by the miR-155/STAT1 feedback. [ABSTRACT FROM AUTHOR]

Abstract Background ETS2 is a downstream effector of the RAS/RAF/ERK pathway, which plays a critical role in the development of malignant tumor. However, the clinical impact of ETS2 expression in AML remains unknown. Methods In this study, we evaluated the prognostic significance of ETS2 expression using two relatively large cohorts of AML patients. Results In the first cohort, compared to low expression of ETS2 (ETS2 low), high expression of ETS2 (ETS2 high) showed significant shorter OS, EFS and RFS in the current treatments including the allogeneic HCT group (n = 72) and the chemotherapy group (n = 100). Notably, among ETS2 high patients, those received allogeneic HCT had longer OS, EFS and RFS than those with chemotherapy alone (allogeneic HCT, n = 39 vs. chemotherapy, n = 47), but treatment modules play insignificant role in the survival of ETS2 low patients (allogeneic HCT, n = 33 vs. chemotherapy, n = 53). Moreover, gene/microRNA expression data provides insights into the biological changes associated with varying ETS2 expression levels in AML. The prognostic value of ETS2 was further validated in the second AML cohort (n = 329). Conclusions Our results indicate that ETS2 high is a poor prognostic factor in AML and may guide treatment decisions towards allogeneic HCT.

The repertoire of aberrant signaling underlying the pathogenesis of lung adenocarcinoma remains largely uncharacterized, which precludes an efficient therapy for these patients, especially when distant metastasis occurs. Cyclin-dependent kinase 10 (CDK10) has been reported to modulate the progression of malignant tumors; however, contradictory effects have been found among different types of malignant tumors. In the present study, we found that CDK10 was downregulated in lung adenocarcinoma compared with the paired adjacent normal lung tissue, and lower expression level of CDK10 was associated with more frequent N2 staged lymph node and distant metastasis, higher TNM stage, and shorter overall survival. Further study indicated that CDK10 inhibited the migration and invasion abilities with no impact on the proliferation of lung adenocarcinoma cells. Mechanistically, CDK10 could bind to and promote the degradation of ETS2, a transcription factor for C-RAF and MMP2/9, thereby inactivating the downstream c-Raf/p-MEK/p-ERK pathway that drives epithelial-mesenchymal transition and impairing the expression of matrix metalloproteinases involved in cell invasion. In addition, the p-MEK/p-ERK pathway conducts a positive feedback regulation on the expression of ETS2. Knockdown of CDK10 in human lung adenocarcinoma cells significantly promoted the formation of metastatic foci in lungs in a xenograft mouse model. In conclusion, CDK10 suppresses metastasis of lung adenocarcinoma by disrupting the ETS2/c-Raf/p-MEK/p-ERK/ETS2 signaling and MMP2/9, providing a new therapeutic target for the treatment of lung adenocarcinoma with metastasis., (© 2023 The Authors. Molecular Carcinogenesis published by Wiley Periodicals LLC.)

Osteoarthritis (OA) is the most common irreversible chronic joint dysfunction disease, which is pathologically characterized by disturbance of articular cartilage homeostasis leading to subsequent inflammatory response and cartilage extracellular matrix (ECM) degradation. Increasing evidence has demonstrated the dysregulation of transcription factors play crucial roles in the occurrence and development of osteoarthritis (OA), but the potential functions and mechanism of most transcription factors in OA has not been completely illuminated. In this study, we identified that transcription factor V-ets erythroblastosis virus E26 oncogene homolog 2 (ETS2) was significantly down-regulated in OA cartilage and IL-1β-induced OA chondrocytes. Functional experiments in vitro demonstrated that the overexpressed ETS2 strikingly enhanced proliferation, outstandingly suppressed apoptosis, and dramatically reduced inflammation and ECM degradation in IL-1β-induced OA chondrocytes, whereas the knockdown of ETS2 led to the opposite effects. Further in vivo studies have shown that up-regulated ETS2 dramatically ameliorates cartilage injury in DMM-induced OA mice. Mechanical studies have disclosed that DNMT1-mediated downregulation of ETS2 dramatically promotes STAT1 by inhibiting miR-155 transcription, and increased STAT1 initiates a feedback loop that may enhance DNMT1-mediated hypermethylation of ETS2 to inhibit ETS2 expression, thus forming a DNMT1/ETS2/miR-155/STAT1 feedback loop that inhibits MAPK signaling pathways and aggravates OA cartilage injury. In all, our results revealed that overexpression of ETS2 markedly ameliorated OA cartilage injury through the ETS2/miR-155/STAT1/DNMT1 feedback loop, providing a new perspective on the pathogenesis and therapeutic strategies for OA., Competing Interests: Declaration of competing interest The authors declare no competing interests., (Copyright © 2023. Published by Elsevier B.V.)

V-ets erythroblastosis virus E26 oncogene homolog 2 (ETS2), belonging to the ETS family of transcription factors, is implicated in a broad range of cellular functions. Recently, ETS2 has been found playing an important role in the progression of some types of cancers. However, it remains unclear whether ETS2 has any effects on renal cell carcinoma (RCC). In this study, we investigated the biological functions of ETS2 in RCC. The results showed that ETS2 was highly expressed in RCC tissues and cell lines and its expression had an association with clinicopathological characteristics of RCC patients. In addition, down-regulation of ETS2 significantly inhibited RCC cell invasion in vitro and metastasis in vivo as well as suppressed the epithelial-mesenchymal transition (EMT) process. We also found that ETS2 down-regulation significantly reduced the levels of PI3K and Akt phosphorylation in RCC cells. Taken together, we suggest that ETS2 is of potential value as a molecular target for RCC treatment. [ABSTRACT FROM AUTHOR]

Since its discovery as an oncoprotein in 1979, investigation into p53's many identities has completed a full circle and today it is inarguably the most extensively studied tumor suppressor (wild-type p53 form or WTp53) and oncogene (mutant p53 form or mtp53) in cancer research. After the p53 protein was declared "Molecule of the Year" by Science in 1993, the p53 field exploded and a plethora of excellent reviews is now available on every aspect of p53 genetics and functional repertoire in a cell. Nevertheless, new functions of p53 continue to emerge. Here, we discuss a novel mechanism that contributes to mtp53's Gain of Functions GOF (gain-of-function) activities and involves the upregulation of both nucleotide de novo synthesis and nucleoside salvage pathways. [ABSTRACT FROM AUTHOR]

The overexpression of metastasis-associated protein 1 (MTA1) in prostate cancer (PCa) contributes to tumor aggressiveness and metastasis. We have reported the inhibition of MTA1 by resveratrol and its potent analog pterostilbene in vitro and in vivo. We have demonstrated that pterostilbene treatment blocks the progression of prostatic intraepithelial neoplasia and adenocarcinoma in mouse models by inhibiting MTA1 expression and signaling. In the current study, we investigated the MTA1 targeted anticancer effects of Gnetin C, a resveratrol dimer, in comparison with resveratrol and pterostilbene. Using DU145 and PC3M PCa cells, we found that Gnetin C downregulates MTA1 more potently than resveratrol and pterostilbene. Further, Gnetin C demonstrated significant MTA1-mediated inhibitory effect on cell viability, colony formation, and migration, while showing a more potent induction of cell death than resveratrol or pterostilbene. In addition, we identified Gnetin C-induced substantial ETS2 (erythroblastosis E26 transformation-specific 2) downregulation, which is not only MTA1-dependent, but is also independent of MTA1 as a possible mechanism for the superior anticancer efficacy of Gnetin C in PCa. Together, these findings underscore the importance of novel potent resveratrol dimer, Gnetin C, as a clinically promising agent for the future development of chemopreventive and possibly combinatorial therapeutic approaches in PCa.

The E26 transformation-specific (ETS) family is one of the largest families of transcription factors. Upon activation by MAPK pathway, ETS participates in cell proliferation, differentiation, migration, apoptosis, and metastasis. However, the mechanism by which ETS is deregulated in cancer is unclear. In this study, the authors investigated the role of ETS factor, ETS2, in hypopharyngeal cancer pathogenesis in hypopharyngeal cancer tissues (N = 20) and corresponding non-neoplastic tissues (N = 20). The results showed that expression of ETS2 was increased in cancer tissues as compared with the expression in corresponding non-neoplastic tissues. Analysis of clinicopathological characteristics showed that increased level of ETS2 is associated with III-IV tumor node metastasis stage and lymph node metastasis. In addition, knockdown of ETS2 by siRNA in pharyngeal cancer cell line, FaDu, significantly decreased cell's vitality and colony-forming ability by inducing caspase-3-dependent apoptosis and cell cycle arrest. Furthermore, inhibition of ETS2 could abrogate the migration, invasion, and transforming growth factor-β-induced epithelial mesenchymal transition through the upregulation of E-cadherin, zona occludens protein-1, together with downregulation of vimentin and α-sooth muscle actin. These functions of ETS2 could be associated with the activation of MAPK/p38/ERK/JNK signals. Taken together, the authors opined that ETS2 functions as an oncogene and plays a key role in the progression of hypopharyngeal cancer. [ABSTRACT FROM AUTHOR]

In five separate families, we identified nine individuals affected by a previously unidentified syndrome characterized by growth retardation, spine malformation, facial dysmorphisms, and developmental delays. Using homozygosity mapping, array CGH, and exome sequencing, we uncovered bi-allelic loss-of-function CDK10 mutations segregating with this disease. CDK10 is a protein kinase that partners with cyclin M to phosphorylate substrates such as ETS2 and PKN2 in order to modulate cellular growth. To validate and model the pathogenicity of these CDK10 germline mutations, we generated conditional-knockout mice. Homozygous Cdk10 -knockout mice died postnatally with severe growth retardation, skeletal defects, and kidney and lung abnormalities, symptoms that partly resemble the disease’s effect in humans. Fibroblasts derived from affected individuals and Cdk10 -knockout mouse embryonic fibroblasts (MEFs) proliferated normally; however, Cdk10 -knockout MEFs developed longer cilia. Comparative transcriptomic analysis of mutant and wild-type mouse organs revealed lipid metabolic changes consistent with growth impairment and altered ciliogenesis in the absence of CDK10. Our results document the CDK10 loss-of-function phenotype and point to a function for CDK10 in transducing signals received at the primary cilia to sustain embryonic and postnatal development. [ABSTRACT FROM AUTHOR]

Background: ETS2 is a downstream effector of the RAS/RAF/ERK pathway, which plays a critical role in the development of malignant tumor. However, the clinical impact of ETS2 expression in AML remains unknown.Methods: In this study, we evaluated the prognostic significance of ETS2 expression using two relatively large cohorts of AML patients.Results: In the first cohort, compared to low expression of ETS2 (ETS2 low), high expression of ETS2 (ETS2 high) showed significant shorter OS, EFS and RFS in the current treatments including the allogeneic HCT group (n = 72) and the chemotherapy group (n = 100). Notably, among ETS2 high patients, those received allogeneic HCT had longer OS, EFS and RFS than those with chemotherapy alone (allogeneic HCT, n = 39 vs. chemotherapy, n = 47), but treatment modules play insignificant role in the survival of ETS2 low patients (allogeneic HCT, n = 33 vs. chemotherapy, n = 53). Moreover, gene/microRNA expression data provides insights into the biological changes associated with varying ETS2 expression levels in AML. The prognostic value of ETS2 was further validated in the second AML cohort (n = 329).Conclusions: Our results indicate that ETS2 high is a poor prognostic factor in AML and may guide treatment decisions towards allogeneic HCT. [ABSTRACT FROM AUTHOR]

People with Down syndrome (DS) are at high risk of developing pathology similar to Alzheimer's disease (AD). Modeling of this pathology in vitro may be useful for studying this phenomenon. In this study, we analyzed three different cultures of neural cells carrying trisomy of chromosome 21, which were generated by directed differentiation from induced pluripotent stem cells (iPS cells). We report here that in vitro generated DS neural cells have abnormal metabolism of amyloid-β (Aβ) manifested by increased secretion and accumulation of Aβ granules of Aβ42 pathological isoform with upregulated expression of the APP gene. Additionally, we found increased expression levels of genes that are considered to be associated with AD (BACE2, RCAN1, ETS2, TMED10), as compared to healthy controls. Thus, the neural cells generated from induced pluripotent stem cells with DS reproduce initial cellular signs of AD-type pathology and can be useful tools for modeling and studying this variant of AD in vitro. [ABSTRACT FROM AUTHOR]

Summary Tumor-associated endothelial cells (TECs) regulate tumor cell aggressiveness. However, the core mechanism by which TECs confer stem cell-like activity to indolent tumors is unknown. Here, we used in vivo murine and human tumor models to identify the tumor-suppressive checkpoint role of TEC-expressed insulin growth factor (IGF) binding protein-7 (IGFBP7/angiomodulin). During tumorigenesis, IGFBP7 blocks IGF1 and inhibits expansion and aggresiveness of tumor stem-like cells (TSCs) expressing IGF1 receptor (IGF1R). However, chemotherapy triggers TECs to suppress IGFBP7, and this stimulates IGF1R + TSCs to express FGF4, inducing a feedforward FGFR1-ETS2 angiocrine cascade that obviates TEC IGFBP7. Thus, loss of IGFBP7 and upregulation of IGF1 activates the FGF4-FGFR1-ETS2 pathway in TECs and converts naive tumor cells to chemoresistant TSCs, thereby facilitating their invasiveness and progression. [ABSTRACT FROM AUTHOR]

TP53 is one of the most frequently inactivated tumor suppressor genes in human cancer. However, unlike other tumor suppressor genes whose expression is lost, TP53 is usually inactivated as a result of a single nucleotide change within the coding region. Typically, these single nucleotide mutations result in a codon change that creates an amino acid substitution. Thus, unlike other tumor suppressor genes whose expression is lost due to genetic or epigenetic changes, the p53 gene primarily suffers missense mutations and therefore the cells retain and express a mutant form of the p53 protein (mtp53). It is now well established that mtp53 contributes to tumor development through its gain-of-function activities. These gain-of-function (GOF) activities can arise from novel protein-protein interactions that can either disable other tumor suppressors (e.g. p63, p73) or enable oncogenes such as ETS2, an ETS family member. In this review, I will focus on the identification of the mtp53/ETS2 complex and outline the diverse activities that this transcriptional regulatory complex controls to promote cancer.

Since its discovery as an oncoprotein in 1979, investigation into p53’s many identities has completed a full circle and today it is inarguably the most extensively studied tumor suppressor (wild-type p53 form or WTp53) and oncogene (mutant p53 form or mtp53) in cancer research. After the p53 protein was declared “Molecule of the Year” by Science in 1993, the p53 field exploded and a plethora of excellent reviews is now available on every aspect of p53 genetics and functional repertoire in a cell. Nevertheless, new functions of p53 continue to emerge. Here, we discuss a novel mechanism that contributes to mtp53’s Gain of Functions GOF (gain-of-function) activities and involves the upregulation of both nucleotide de novo synthesis and nucleoside salvage pathways.

Helicobacter pylori infection is one of the most potent factors leading to gastric carcinogenesis. The seven in absentia homologue (Siah2) is an E3 ubiquitin ligase which has been implicated in various cancers but its role in H. pylori-mediated gastric carcinogenesis has not been established. We investigated the involvement of Siah2 in gastric cancer metastasis which was assessed by invasiveness and migration of H. pylori-infected gastric epithelial cancer cells. Cultured gastric cancer cells (GCCs)MKN45, AGS and Kato III showed significantly induced expression of Siah2, increased invasiveness and migration after being challenged with the pathogen. Siah2-expressing stable cells showed increased invasiveness and migration after H. pylori infection. Siah2 was transcriptionally activated by E26 transformation-specific sequence 2 (ETS2)- and Twist-related protein 1 (Twist1) induced in H. pylori-infected gastric epithelial cells. These transcription factors dose-dependently enhanced the aggressiveness of infected GCCs. Our data suggested that H. pylori-infected GCCs gained cell motility and invasiveness through Siah2 induction. As gastric cancer biopsy samples also showed highly induced expression of ETS2, Twist1 and Siah2 compared with noncancerous gastric tissue, we surmise that ETS2- and Twist1-mediated Siah2 up-regulation has potential diagnostic and prognostic significance and could be targeted for therapeutic purpose. [ABSTRACT FROM AUTHOR]

TP53 is one of the most frequently inactivated tumor suppressor genes in human cancer . However, unlike other tumor suppressor genes whose expression is lost, TP53 is usually inactivated as a result of a single nucleotide change within the coding region. Typically, these single nucleotide mutations result in a codon change that creates an amino acid substitution. Thus, unlike other tumor suppressor genes whose expression is lost due to genetic or epigenetic changes, the p53 gene primarily suffers missense mutations, and therefore, the cells retain and express a mutant form of the p53 protein (mtp53). It is now well established that mtp53 contributes to tumor development through its gain-of-function (GOF) activities. These GOF activities can arise from novel protein--protein interactions that can either disable other tumor suppressors (e.g., p63 and p73) or enable oncogenes such as ETS2, an ETS family member. In this review, I will focus on the identification of the mtp53/ETS2 complex and outline the diverse activities that this transcriptional regulatory complex controls to promote cancer. [ABSTRACT FROM AUTHOR]

Down syndrome (trisomy 21) neurons display an increased rate of apoptosis in vitro. The genes on chromosome 21 that mediate this increased cell death remain to be elucidated. Here we show that the chromosome 21 transcription factor Ets2, a gene that is overexpressed in Down syndrome, is expressed in neurons, and that moderate overexpression of Ets2 leads to increased apoptosis of primary neuronal cultures from Ets2 tg mice that involves activation of caspase-3. Our data therefore suggest that overexpression of ETS2 may contribute to the increased rate of apoptosis of neurons in Down syndrome.

The present study demonstrated the acquisition of additional malignant characteristics in irradiated mouse fibrosarcoma cells compared with the parent cells. Several reporter assays indicated that hypoxia-inducible factor (HIF)-1a, activator protein-1 and Ets-dependent transcription were activated in irradiated cells. The cis-elements in the 5'-untranslated region (UTR) of these transcription factors plays a major role in their expression in surviving irradiated cancer cells. By contrast, there were no evident differences between the 3'-UTR-dependent repression demonstrated by parent cells and irradiated cells. A small population of parental fibrosarcoma cells was also found to exhibit the same enhanced 5'-UTR-dependent HIF-1α expression as that demonstrated by irradiated cells. These observations may indicate that high-dose X-ray irradiation affects the majority of proliferating cancer cells, but not the cancer stem cells (CSCs), and an increased CSC population may explain the progressive phenotypes of the irradiated cells. It appears likely that the transcription factors that maintain stemness are regulated by the same 5'-UTR-dependent mechanism. [ABSTRACT FROM AUTHOR]

Overexpression of the transcription factor (TF) ATOH1 is known to induce the transformation of nonsensory cells in the organ of Corti into hair cells (HCs). Evaluating DNA 5′ to the coding sequence of the pou4f3 gene, a target of ATOH1 in HCs, we identified in three regions containing clustered binding sites for ATOH1 and several other TFs that are expressed in developing inner ear sensory epithelia at the time of HC specification. These regions and sites are highly conserved across evolutionarily distant mammalian species. To test the hypothesis that the identified TFs act in combination to regulate the pou4f3 gene, we transfected by electroporation neonatal cochlear sensory epithelium from mice expressing green fluorescent protein (GFP) under the control of an 8.5-kb 5' pou4f3 genomic fragment. Plasmids encoding 21 TFs c-transfected with human ATOH1 (hATOH1). Co-transfection with hETV4, hNMYC, or hETS2 produced significantly more pou4f3/GFP and myosin7A-positive nonsensory cells than hATOH1 alone. Co-transfection of hATOH1 with hHES1, hHES5, or hNEUROD1 reduced the effects of hATOH1. Chromatin immunoprecipitation (ChIP) of DNA from an inner ear cell line transfected with hNMYC, hETV4, or hETS2 revealed binding to a conserved region immediately proximal to the coding sequence. ChIP similarly revealed binding of hGATA3, hNMYC, and hTFE2 to a region several kilobases distal to the coding sequence, which we have previously shown to bind ATOH1. The results suggest that ATOH1 acts in concert with a subset of other TFs to directly regulate the pou4f3 gene and more broadly to regulate the HC phenotype. [ABSTRACT FROM AUTHOR]

The ETS superfamily transcription factors Elf5 and Ets2 have both been implicated in the maintenance of the extraembryonic ectoderm (ExE) of the mouse embryo. While homozygous mutants of either gene result in various degrees of ExE tissue loss, heterozygotes are without phenotype. We show here that compound heterozygous mutants exhibit a phenotype intermediate to that of the more severe Elf5 −/− and the milder Ets2 −/− mutants. Functional redundancy is shown via commonalities in expression patterns, in target gene expression, and by partial rescue of Elf5 −/− mutants through overexpressing Ets2 in an Elf5-like fashion. A model is presented suggesting the functional division of the ExE region into a proximal and distal domain based on gene expression patterns and the proximal to distal increasing sensitivity to threshold levels of combined Elf5 and Ets2 activity. [ABSTRACT FROM AUTHOR]

Haemophilus parasuis is a widespread bacterial pathogen causing acute systemic inflammation and leading to the sudden death of piglets. Resistin, a multifunctional peptide hormone previously demonstrated to influence the inflammation in porcine, was extremely increased in H. parasuis -infected tissues. However, the mechanism of resistin expression regulation in porcine, especially during pathogen infection, remains unclear. In the present study, we explored for the first time the transcription factor and signaling pathway mediating the expression of pig resistin during H. parasuis stimulation. We found that H. parasuis induced the expression of pig resistin in a time- and dose-dependent manner via the transcription factor Ets2 in porcine alveolar macrophages during H. parasuis stimulation. Moreover, the expression of Ets2 was mediated by the activation of the p38 MAPK pathway induced by H. parasuis , thus promoting resistin production. These results revealed a novel view of the molecular mechanism of pig resistin production during acute inflammation induced by pathogenic bacteria. ● H. parasuis induces expression of resistin in porcine alveolar macrophages. ● The transcription factor Ets2 regulates expression of resistin during H. parasuis infection. ● p38 MAPK pathway regulates the expression of resistin via transcription factor Ets2. [ABSTRACT FROM AUTHOR]

Background: Proper expression and functioning of transcription factors (TFs) are essential for regulation of different traits and thus could be crucial for the development of complex diseases. Subjects with Down syndrome (DS) have a higher incidence of acute lymphoblastic leukemia (ALL) while solid tumors, like breast cancer (BC) and oral cancer (OC), show rare incidences. Triplication of the human chromosome 21 in DS is associated with altered genetic dosage of different TFs. V-ets erythroblastosis virus E26 oncogene homolog 2 (ETS2) and Single Minded 2 (SIM2) are two such TFs that regulate several downstream genes involved in developmental and neurological pathways. Here we studied functional genetic polymorphisms (fSNP) in ETS2 and SIM2 encoding genes in a group of patients and control subjects to better understand association of these variants with DS phenotypes. Methods: We employed an in silico approach to identify potential target pathways of ETS2 and SIM2. fSNPs in genes encoding for these two TFs were identified using available databases. Selected sites were genotyped in individuals with DS, their parents, ALL, BC, OC as well as ethnically matched control individuals. We further analyzed these data by population-based statistical methods. Results: Allelic/genotypic association analysis showed significant (P < 0.03) differences of rs2070530, rs1051476, rs11254, rs711 for DS subjects compared to control. rs711 also exhibited significantly different genotypic distribution pattern in parents of DS probands (P < 0.02) and BC patients (P < 0.02). Interaction analysis revealed independent main effect of rs711 in all the groups, while rs11254 exhibited independent main effect in DS subjects only. High entropy values were noticed for rs461155 in the solid tumor groups. Significant interactive effects of rs2070531 with rs1051475, rs1051476, rs11254 were observed in all the groups except DS. Conclusions: We infer from the present investigation that the difference in frequencies of fSNPs and their independent as well as interactive effects may be the cause for altered expression of SIM2 and ETS2 in DS and malignant groups, which affects different downstream biological pathways. Thus, altered expression of SIM2 and ETS2 could be one of the reasons for variable occurrence of different malignant conditions in DS. [ABSTRACT FROM AUTHOR]

Objective: This study was to observe the levels of Ets2 mRNA expression in leukemia patients and investigate the effect of small interfering RNA (siRNA) targeting Ets2 gene on sensibility of human acute monocytic leukemic cell line SHI-1 cells to etoposide (VP-16). SHI-1 cells to etoposide (VP-16). Methods: Ets2 mRNA levels were determined by reverse transcription polymerase chain reaction (RT-PCR). reaction (RT-PCR). After the transfection of Ets2 siRNA to SHI-1 cells by electroporation method, qRT-PCR was used to detect Ets2 gene expression in these cells; VP-16-induced apoptosis was investigated by Annexin V-FITC/PI. Ets2 gene expression in these cells; VP-16-induced apoptosis was investigated by Annexin V-FITC/PI. Results: Ets2 mRNA was detectable in SHI-cells. was detectable in SHI-cells. The Ets2 expression rate was respectively 10% in 5 healthy volunteers, 60% in 5 acute lymphocytic leukemia (ALL) patients, 73. leukemia (ALL) patients, 73. 68% in 19 acute nonlymphocytic leukemia (ANLL) patients and 100% in 4 chronic myeloid leukemia (CML) patients. leukemia (CML) patients. The expression levels of Ets2 mRNA were significantly higher in leukemia patients compared with healthy volunteers. healthy volunteers. It also showed that siRNA targeting Ets2 gene resulted in substantial loss of Ets2 mRNA of SHI-1 cells compared to the control groups. compared to the control groups. Downregulation of Ets2 gene expression increased SHI-1 cells apoptosis and VP-16-induced apoptosis of SHI-1 cells. apoptosis of SHI-1 cells. Conclusion: The high-level expression of Ets2 transcription factor in leukemia cells were connected with proliferation and anti-apoptosis of leukemia cells. with proliferation and anti-apoptosis of leukemia cells. SiRNA mediated Ets2 gene silencing induced cell apoptosis and enhanced in vitro sensitivity to chemotherapy (VP-16) of SHI-1 cells. in vitro sensitivity to chemotherapy (VP-16) of SHI-1 cells. It speculated the high-level expression of Ets2 may actually be an unfavorable determinant of chemotherapy sensitivity in leukemia. be an unfavorable determinant of chemotherapy sensitivity in leukemia. [ABSTRACT FROM AUTHOR]

Trisomy of the 21{st} chromosome leads to an over dosage of several regulatory genes in Down syndrome (DS). Though allelic and genotypic combinations formed between genes are interesting, till date, this particular area has never been explored in DS. In the present investigation four SNPs in two transcription factors, Single minded 2 (SIM2) and V-ets erythroblastosis virus E26 oncogene homolog2 (ETS2), located in the 21{st} chromosome were genotyped to understand their role in DS. Genomic DNA of eastern Indian probands with DS (N=132), their parents (N=209) and ethnically matched controls (N=149) was subjected to PCR-based analyses of functionally important SNPs followed by statistical analyses. ETS2 rs461155 showed high heterozygosity in DS. Significantly lower frequency of SIM2 C-G haplotype (rs2073601-rs2073416) was noticed in individuals with DS (P value =0.01669) and their fathers (P value=0.01185). Significantly lower frequency of the A-C-C-G with higher frequency of A-C-A-G haplotypes was also noticed in subjects with DS (P value =0.02089 and 0.00588 respectively). Data obtained indicate that the rs2073601 'A' allele, responsible for nonsynonymous substitution of leucine to methionine, may have some role in DS in this population. [ABSTRACT FROM AUTHOR]

Abstract: Mouse trophoblast stem (TS) cells represent a unique in vitro system that provides an unlimited supply of TS cells for the study of trophoblast differentiation and TS cell self-renewal. Although the mouse transcription factor Ets2 is required for TS cell self-renewal, its role in this and in TS cell differentiation has not been explored fully, partly due to the early lethality of Ets2 null mice. To address this, we developed a novel lentivirus-based system that resulted in efficient Ets2 knockdown in the overwhelming majority of TS cells. This system enables functional studies in TS cells, especially for genes required for TS cell self-renewal because TS cell derivation using gene-knockout embryos for such genes depends on TS cell self-renewal. Using morphological/morphometric criteria and gene expression analysis, we show that the requirement for Ets2 in self-renewal of TS cells cultured in ‘stem cell medium’ (SCM) involves maintenance of the expression of genes that inhibit TS cell differentiation in SCM, such as Cdx2 and Esrrb, and preservation of the undifferentiated TS cell morphology. During TS cell differentiation caused by Cdx2/Esrrb downregulation, due to either Ets2 knockdown in SCM or culture in differentiation medium (DM), Ets2 is also required for the promotion of trophoblast giant cell (TGC) and junctional zone trophoblast (JZT) differentiation. This TGC differentiation involves Ets2-dependent expression of Hand1, a gene required for the differentiation of all TGC types. This study uncovers new roles for Ets2 in TS cell self-renewal and differentiation and demonstrates the usefulness of this lentivirus system for gene function studies in TS cells. [Copyright &y& Elsevier]

Ras/MAPK signaling is often aberrantly activated in human cancers. The downstream effectors are transcription factors, including those encoded by the ETS gene family. Using cell-based assays and biophysical measurements, we have determined the mechanism by which Ras/MAPK signaling affects the function of Etsi via phosphorylation of Thr38 and Ser4i. These ERK2 phosphoacceptors lie within the unstructured N-terminal region of Etsi, immediately adjacent to the PNT domain. NMR spéctroscopic analyses demonstrated that the PNT domain is a four-helix bundle (H2-H5), resembling the SAM domain, appended with two additional helices (H0-Hi). Phosphorylation shifted a conformational equilibrium, displacing the dynamic helix HO from the core bundle. The affinity of Etsi for the TAZ1 (or CH1) domain of the coactivator CBP was enhanced 34-fold by phosphorylation, and this binding was sensitive to ionic strength. NMR-monitored titration experiments mapped the interaction surfaces of the TAZ1 domain and Etsi, the latter encompassing both the phosphoacceptors and PNT domain. Charge complementarity of these surfaces indicate that electrostatic forces act in concert with a conformational equilibrium to mediate phosphorylation effects. We conclude that the dynamic helical elements of Etsi, appended to a conserved structural core, constitute a phospho-switch that directs Ras/MAPK signaling to downstream changes in gene expression. This detailed structural and mechanistic information will guide strategies for targeting ETS proteins in human disease. [ABSTRACT FROM AUTHOR]

Abstract: Triplex-forming oligonucleotides (TFOs) are attractive tools to control gene expression at the transcriptional level. This anti-gene approach has proven to be successful in various experimental settings. However, the mechanisms leading to transcriptional repression in cells have not been fully investigated yet. Here, we examined the consequence of triplex DNA formation on the binding of transcriptional activators, co-activators and RNA Polymerase II to the ets2 gene promoter using chromatin immunoprecipitation assays. The triplex target sequence was located approximately 40-bp upstream of the transcription start site (TSS) and overlapped an Sp1 binding site relevant for ets2 transcription. We found that the ets2-TFO prevented binding of Sp1, TAFII130 and TAFII250 to the ets2 promoter, while binding of RNA polymerase II and TBP were not affected. The effects were both sequence and target specific, since the TFO had no effect on the c-myc promoter and a mutated ets2 promoter construct. Thus, triplex DNA formation near a TSS leads to formation of a non-functional pre-initiation complex (PIC) by blocking binding of transcriptional activators and co-activator molecules. This is the first direct demonstration of interference with PIC assembly at the TSS by oligonucleotide-triplex DNA formation in cells. [Copyright &y& Elsevier]

Summary: Tissue engineering offers an exciting prospect for reconstructive surgery by replacing missing natural scaffolds with artificial ones. For optimal success the artificial scaffold should provide an environment closely resembling the natural tissue. Little is known about the direct influence of the scaffold on the expression of regulators of bone development, such as transcription factors. The aim of this study was to investigate the influence of the scaffold material on the expression of V-ets erythroblastosis virus E26 oncogene homolog 2 (avian) (Ets2), a key transcription factor in bone biology. Human primary bone precursor cells were seeded in three-dimensional constructs consisting of hydroxyapatite (HA) or poly (lactic-co-glycolic acid) (PLGA). Cells grown on tissue culture polystyrene dishes served as controls. After cultivation for up to 21 days the expression of Ets2 and other important bone-specific genes was assessed by reverse transcription polymerase chain reaction (RT-PCR) and Western Blotting. Ets2 mRNA showed significantly higher expression in controls than in bone-like constructs, and more Ets2 mRNA was expressed in cells grown in HA than in PLGA constructs. At protein level however, Ets2 expression was higher in constructs than in controls after prolonged culture. Our study showed for the first time a differential expression of Ets2 in tissue engineered bone constructs in vitro, demonstrating that scaffold chemistry has an influence on the expression of genes regulating osteogenesis. [Copyright &y& Elsevier]

Abstract: PC is made via the CDP-choline pathway, in which CTP:phosphocholine cytidylyltransferase α (CTα), encoded by Pcyt1a, is the rate-limiting enzyme whose mRNA expression is strictly regulated. Previously, we reported that Ets1 enhanced and Net repressed CTα transcription by binding at the Ets binding site (−49/−47) in the Pcyt1a promoter. In this study, we asked if an Ets1 analogue, Ets2, also regulates CTα transcription and investigated the importance of its nuclear localization signal (NLS) and nuclear export signal (NES). Ets2 is primarily detected in the nucleus. Various mutated Ets2 proteins fused with enhanced green fluorescent protein were constructed to identify the NLS and NES in Ets2. Mutation of Ets2 at amino acids 404–410 results in a protein that is evenly distributed in the cell. Interestingly, an Ets2 protein deleted at the C-terminus (amino acids 1–392 present) was localized to the cytoplasm and site-specific mutation in the region 364–372 of this construct resulted in cytoplasmic and nuclear distribution. These results suggest that the NLS in Ets2 is between amino acids 404 and 410, and that the NES is between amino acids 364 and 372. Ets2 enhanced, but the mutant forms of Ets2 had little effects on the transcription of a CTα-reporter construct. When RAW264 cells, murine macrophage cell-line, were stimulated with 12-O-tetradecanoylphorbol-13-acetate (TPA) or macrophage-colony stimulating factor, the transcription of CTα was enhanced accompanied by increased mRNA of Ets2. These results suggest that the induction of Ets2 is important for CTα transcription by TPA and macrophage-colony stimulating factor. [Copyright &y& Elsevier]

Acute myeloid leukemia (AML) in Down syndrome (DS) children has several unique features including a predominance of the acute megakaryocytic leukemia (AMkL) phenotype, higher event-free survivals compared to non-DS children using cytosine arabinoside (ara-C)/anthracycline-based protocols and a uniform presence of somatic mutations in the X-linked transcription factor gene, GATA1. Several chromosome 21-localized transcription factor oncogenes including ETS2 may contribute to the unique features of DS AMkL. ETS2 transcripts measured by real-time RT-PCR were 1.8- and 4.1-fold, respectively, higher in DS and non-DS megakaryoblasts than those in non-DS myeloblasts. In a doxycycline-inducible erythroleukemia cell line, K562pTet-on/ETS2, induction of ETS2 resulted in an erythroid to megakaryocytic phenotypic switch independent of GATA1 levels. Microarray analysis of doxycycline-induced and doxycycline-uninduced cells revealed an upregulation by ETS2 of cytokines (for example, interleukin 1 and CSF2) and transcription factors (for example, TAL1), which are key regulators of megakaryocytic differentiation. In the K562pTet-on/ETS2 cells, ETS2 induction conferred differences in sensitivities to ara-C and daunorubicin, depending on GATA1 levels. These results suggest that ETS2 expression is linked to the biology of AMkL in both DS and non-DS children, and that ETS2 acts by regulating expression of hematopoietic lineage and transcription factor genes involved in erythropoiesis and megakaryopoiesis, and in chemotherapy sensitivities. [ABSTRACT FROM AUTHOR]

Abstract: The Ets2 transcription factor is essential for the development of the mouse placenta and for generating signals for embryonic mesoderm and axis formation. Using a conditional targeted Ets2 allele, we show that Ets2 is essential for trophoblast stem (TS) cells self-renewal. Inactivation of Ets2 results in TS cell slower growth, increased expression of a subset of differentiation-associated genes and decreased expression of several genes implicated in TS self-renewal. Among the direct TS targets of Ets2 is Cdx2, a key master regulator of TS cell state. Thus Ets2 contributes to the regulation of multiple genes important for maintaining the undifferentiated state of TS cells and as candidate signals for embryonic development. [Copyright &y& Elsevier]

The transcription factor Ets2 and its transcriptional targets osteopontin (OPN) and osteocalcin (OC) are expressed in tissue-engineered bone constructs in vitro. Up to now little is known about the role of Ets2 in tissue-engineering applications. This study was intended to investigate the hypothesis that protein expression of Ets2 is correlated with the expression of bone-specific proteinsin tissue-engineeredbone constructs. Cell-seeded three-dimensional bone constructs manufactured with osteoblastic cells and poly(lactic-co-glycolic acid) polymer fleeces over a period of 21 days were analyzed by SDS-PAGE and Western blotting. The protein expression of OPN, OC, osteonectin and collagen type I was analyzed. Cellularity, alkaline phosphatase-specific activity and histology confirmed the osteoblastic phenotype of the constructs. Correlations between Ets2 expression and OPN and Ets2 and collagen type I expression could be detected during the phase of late osteoblastic differentiation between days 9 and 21. The correlation between OC and collagen type I was significant in this late stage of osteoblastic differentiation. These results suggest that there is a strong interplay of Ets2 with bone-specific proteins in cell-seeded three-dimensional bone constructs. This study is a crucial step to elucidate the complex interplay of bone-related proteins in the application of bone tissue engineering. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The ETS family is a diverse group of transcription factors that control the expressions of genes that participate in an array of cellular activities, ranging from mitosis to apoptosis. As a consequence of regulating these processes, most ETS factors are oncogenic. However, there is growing evidence that ETS factors are also essential to regulation of the immune system. Of the 29 recognized ETS factors, nine are known to regulate genes involved in immunity, including Ets1, Ets2, GABP, Fli1, Elf1, MEF, ESE1, PU.1, and SpiB. These ETS factors typically activate the transcription of genes associated with pathogen and tumor defense, but several also demonstrate ability to repress transcription. Ets1 and PU.1 appear to have the greatest impact on immunity, primarily through their control of immune cell development. Alterations of Fli1 and Elf1 expression are associated with autoimmunity, emphasizing the role of ETS factors as not only positive, but also negative regulators of immunity. This review summarizes the roles of ETS factors in development of the immune system, defense against pathogens and malignancies, and self-tolerance. [ABSTRACT FROM AUTHOR]

There has been considerable interest in researching the regulatory mechanisms that control the synthesis of interleukin (IL)-12, which plays a central role in the differentiation of T-helper-1 cells. In this study, we performed a series of transient transfection experiments designed to elucidate the functional relationship between the IL-12 promoter-specific transcription factors (Ets2 and Sp1) and histone acetylation modification in IL-12 regulation mediated by p300 and various histone deacetylases (HDACs). Results presented in this report demonstrated that the transcription factors Ets2 and Sp1 acted synergistically with p300 to activate the human IL-12 promoter. The histone acetyltransferase (HAT) activity of p300 was required for this synergic effect, because the adenovirus E1 A protein inhibited the synergy. Conversely, HDACs repressed the synergic effect of transcription factors and histone acetylation on the activation of IL-12, while p300 was able to rectify it. These data indicated that Ets2 and Sp1 worked concertedly and synergistically with p300 in the regulation of human IL-12 expression. Edited by Ming-Hua XU [ABSTRACT FROM AUTHOR]