scholarly journals Polycystin‐1 modulates RUNX2 activation and osteocalcin gene expression via ERK signalling in a human craniosynostosis cell model

2021 ◽  
Author(s):  
Maira Katsianou ◽  
Kostas A. Papavassiliou ◽  
Ilianna Zoi ◽  
Antonios N. Gargalionis ◽  
Dimitrios Panagopoulos ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Model ◽  
Osteocalcin Gene

scholarly journals c-Jun N-Terminal Kinase Activation of Activator Protein-1 Underlies Homologous Regulation of the Gonadotropin-Releasing Hormone Receptor Gene in αT3-1 Cells

Endocrinology ◽  
2003 ◽  
Vol 144 (3) ◽  
pp. 839-849 ◽  
Author(s):  
Buffy S. Ellsworth ◽  
Brett R. White ◽  
Ann T. Burns ◽  
Brian D. Cherrington ◽  
Annette M. Otis ◽  
...  
Keyword(s):  
Gene Expression ◽  
Protein Kinase ◽  
Cell Model ◽  
Receptor Gene ◽  
Critical Role ◽  
Dominant Negative ◽  
Activator Protein 1 ◽  
Activator Protein

Reproductive function is dependent on the interaction between GnRH and its cognate receptor found on gonadotrope cells of the anterior pituitary gland. GnRH activation of the GnRH receptor (GnRHR) is a potent stimulus for increased expression of multiple genes including the gene encoding the GnRHR itself. Thus, homologous regulation of the GnRHR is an important mechanism underlying gonadotrope sensitivity to GnRH. Previously, we have found that GnRH induction of GnRHR gene expression in αT3-1 cells is partially mediated by protein kinase C activation of a canonical activator protein-1 (AP-1) element. In contrast, protein kinase A and a cAMP response element-like element have been implicated in mediating the GnRH response of the GnRHR gene using a heterologous cell model (GGH3). Herein we find that selective removal of the canonical AP-1 site leads to a loss of GnRH regulation of the GnRHR promoter in transgenic mice. Thus, an intact AP-1 element is necessary for GnRH responsiveness of the GnRHR gene both in vitro and in vivo. Based on in vitro analyses, GnRH appeared to enhance the interaction of JunD, FosB, and c-Fos at the GnRHR AP-1 element. Although enhanced binding of cFos reflected an increase in gene expression, GnRH appeared to regulate both FosB and JunD at a posttranslational level. Neither overexpression of a constitutively active Raf-kinase nor pharmacological blockade of GnRH-induced ERK activation eliminated the GnRH response of the GnRHR promoter. GnRH responsiveness was, however, lost in αT3-1 cells that stably express a dominant-negative c-Jun N-terminal kinase (JNK) kinase, suggesting a critical role for JNK in mediating GnRH regulation of the GnRHR gene. Consistent with this possibility, we find that the ability of forskolin and membrane-permeable forms of cAMP to inhibit the GnRH response of the GnRHR promoter is associated with a loss of both JNK activation and GnRH-mediated recruitment of the primary AP-1-binding components.

scholarly journals Evolution Of Acute Myelogenous Leukemia Stem Cell Properties Following Treatment and Progression

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 883-883 ◽  
Author(s):  
TzuChieh Ho ◽  
Mark W LaMere ◽  
Kristen O'Dwyer ◽  
Jason H. Mendler ◽  
Jane L. Liesveld ◽  
...  
Keyword(s):  
Gene Expression ◽  
Stem Cell ◽  
Acute Myelogenous Leukemia ◽  
Cell Model ◽  
Phenotypic Diversity ◽  
Hierarchical Organization ◽  
Myelogenous Leukemia ◽  
Leukemic Cells ◽  
Leukemia Stem Cell ◽  
Acute Myelogenous

Abstract Acute Myelogenous Leukemia (AML) is a disease that clinically evolves over time as many patients who are responsive to therapy upfront acquire resistance to the same agents when applied in the relapse setting. The stem cell model for AML has been invoked to explain primary resistance to standard therapy; the leukemia stem cell (LSC) population representing a therapy-refractory reservoir for relapse. There have been no prospective efforts to formally assess the evolution of the LSC population during patients’ clinical course. We performed a prospective characterization of specimens from a well-defined cohort of patients with AML at diagnosis and relapse to assess the frequency and phenotype of functionally defined LSCs. Methods Primary bone marrow and peripheral blood samples were collected on IRB approved protocols from patients with newly diagnosed AML undergoing induction therapy. Twenty-five patients who relapsed after achieving a complete remission were selected for further study. Screening studies identified seven patients whose pre-therapy samples demonstrated sustained engraftment of NSG mice following transplantation. Pre-therapy and post-relapse LSC frequencies were assessed using xenotransplantation limiting dilution analyses (LDA). We assessed the frequencies of CD45RA, CD32, TIM-3, CD96, CD47, and CD97 expressing populations that have been previously published to possess LSC activity. Functionally validated pre-therapy and post-relapse LSC populations were identified using fluorescent labeled cell sorting and NSG xenotransplantation. LSC activity was confirmed for each population using secondary xenotransplantation. Gene expression analysis of highly enriched LSC populations from pre-therapy and post-relapse samples was performed using ABI TILDA qPCR analyses following pre-amplification. Results We demonstrated by LDA an 8 to 42-fold increase in LSC frequency between diagnosis and relapse in paired primary patient samples. The increase in LSC activity was not associated with an increase in frequency for phenotypically-defined populations previously reported to possess LSC activity. Rather, we found that LSC activity expanded at relapse to immunophenotypic populations of leukemic cells that did not possess LSC activity prior to treatment. Moreover, in all patients, the number of phenotypically distinct LSC populations (as defined by CD34 and CD38 or CD32 and CD38) detectable at relapse was dramatically expanded. Further, while the majority of the LSC populations’ gene expression profile remained stable between diagnosis and relapse, a subset of genes were enriched in defined LSC populations at relapse including IL3-receptor alpha and IL1-RAP, both previously demonstrated to play a role in LSC biology. Conclusions This study is the first to characterize the natural evolution of LSCs in vivo following treatment and relapse. We demonstrate an increase in LSC activity and greatly increased phenotypic diversity of the LSC population, suggesting a loss of hierarchical organization following relapse. These findings demonstrate that treatment of AML patients with conventional chemotherapy regimens can promote quantitative and qualitative expansion of the LSC compartment. Further, the data indicate that surface antigen immune-phenotype is not predictive of function in relapse and suggest a major limitation to efforts targeting specific surface antigens in the relapse setting. Understanding the mechanisms by which LSC expansion occurs and how to target it will likely improve our currently poor treatment options for patients who relapse. Disclosures: Becker: Millenium: Research Funding.

scholarly journals Registered report: Transcriptional amplification in tumor cells with elevated c-Myc

eLife ◽  
2015 ◽  
Vol 4 ◽  
Author(s):  
David Blum ◽  
Haiping Hao ◽  
Michael McCarthy ◽  
Keyword(s):  
Gene Expression ◽  
Tumor Cells ◽  
Cancer Biology ◽  
Cell Model ◽  
Scientific Research ◽  
Digital Gene Expression ◽  
Open Science ◽  
Large Set ◽  
Mrna Levels ◽  
Transcriptional Amplification

The Reproducibility Project: Cancer Biology seeks to address growing concerns about reproducibility in scientific research by conducting replications of 50 papers in the field of cancer biology published between 2010 and 2012. This Registered report describes the proposed replication plan of key experiments from ‘Transcriptional amplification in tumor cells with elevated c-Myc’ by <xref ref-type="bibr" rid="bib5">Lin et al. (2012)</xref>, published in Cell in 2012. The experiments that will be replicated are those reported in Figures 3E and 3F. In these experiments, elevated levels of c-Myc in the P493-6 cell model of Burkitt's lymphoma results in an increase of the total level of RNA using UV/VIS spectrophotometry (Figure 3E; <xref ref-type="bibr" rid="bib5">Lin et al., 2012</xref>) and on the mRNA levels/cell for a large set of genes using digital gene expression technology (Figure 3F; <xref ref-type="bibr" rid="bib5">Lin et al., 2012</xref>). The Reproducibility Project: Cancer Biology is a collaboration between the Center for Open Science and Science Exchange, and the results of the replications will be published in eLife.

scholarly journals Functional Interference Between AP-1 and the Vitamin D Receptor on Osteocalcin Gene Expression in Human Osteosarcoma Cells

1994 ◽  
Vol 224 (1) ◽  
pp. 11-20 ◽  
Author(s):  
Tiina Jaaskelainen ◽  
Asta Pirskanen ◽  
Sanna Ryhanen ◽  
Jorma J. Palvimo ◽  
Hector F. Deluca ◽  
...  
Keyword(s):  
Gene Expression ◽  
Vitamin D ◽  
Vitamin D Receptor ◽  
Osteosarcoma Cells ◽  
Human Osteosarcoma ◽  
Functional Interference ◽  
Human Osteosarcoma Cells ◽  
Osteocalcin Gene

scholarly journals The neutrophil-mobilizing cytokine interleukin-26 in the airways of long-term tobacco smokers

2018 ◽  
Vol 132 (9) ◽  
pp. 959-983 ◽  
Author(s):  
Karlhans Fru Che ◽  
Ellen Tufvesson ◽  
Sara Tengvall ◽  
Elisa Lappi-Blanco ◽  
Riitta Kaarteenaho ◽  
...  
Keyword(s):  
Gene Expression ◽  
Chronic Bronchitis ◽  
Pathogenic Bacteria ◽  
Cell Model ◽  
Water Soluble ◽  
Chronic Obstructive ◽  
Neutrophil Accumulation

Long-term tobacco smokers with chronic obstructive pulmonary disease (COPD) or chronic bronchitis display an excessive accumulation of neutrophils in the airways; an inflammation that responds poorly to established therapy. Thus, there is a need to identify new molecular targets for the development of effective therapy. Here, we hypothesized that the neutrophil-mobilizing cytokine interleukin (IL)-26 (IL-26) is involved in airway inflammation amongst long-term tobacco smokers with or without COPD, chronic bronchitis or colonization by pathogenic bacteria. By analyzing bronchoalveolar lavage (BAL), bronchail wash (BW) and induced sputum (IS) samples, we found increased extracellular IL-26 protein in the airways of long-term smokers in vivo without further increase amongst those with clinically stable COPD. In human alveolar macrophages (AM) in vitro, the exposure to water-soluble tobacco smoke components (WTC) enhanced IL-26 gene and protein. In this cell model, the same exposure increased gene expression of the IL-26 receptor complex (IL10R2 and IL20R1) and nuclear factor κ B (NF-κB); a proven regulator of IL-26 production. In the same cell model, recombinant human IL-26 in vitro caused a concentration-dependent increase in the gene expression of NF-κB and several pro-inflammatory cytokines. In the long-term smokers, we also observed that extracellular IL-26 protein in BAL samples correlates with measures of lung function, tobacco load, and several markers of neutrophil accumulation. Extracellular IL-26 was further increased in long-term smokers with exacerbations of COPD (IS samples), with chronic bronchitis (BAL samples ) or with colonization by pathogenic bacteria (IS and BW samples). Thus, IL-26 in the airways emerges as a promising target for improving the understanding of the pathogenic mechanisms behind several pulmonary morbidities in long-term tobacco smokers.

miR-30e-5p regulates autophagy and apoptosis by targeting Beclin1 involved in contrast-induced acute kidney injury

2021 ◽  
Vol 28 ◽  
Author(s):  
Xiaoqin Liu ◽  
Qingzhao Li ◽  
Lixin Sun ◽  
Limei Chen ◽  
Yue Li ◽  
...  
Keyword(s):  
Gene Expression ◽  
Acute Kidney Injury ◽  
Cell Apoptosis ◽  
Cell Injury ◽  
Cell Model ◽  
Kidney Injury ◽  
Cell Vitality ◽  
A Cell ◽  
Renal Tubular ◽  
Induced Apoptosis

Aims: This study aims to verify if miR-30e-5p targets Beclin1 (BECN1), a key regulator of autophagy, and investigate the function of miR-30e-5p and Beclin1 through mediating autophagy and apoptosis in contrast-induced acute kidney injury (CI-AKI). Methods: Human renal tubular epithelial HK-2 cells were treated with Urografin to construct a cell model of CI-AKI. Real-time reverse transcription–polymerase chain reaction was used to detect gene expression. The dual-luciferase reporting assay and endogenous validation were used to verify targeting and regulating function. The expressions of protein were detected using Western blot. Cell proliferation was detected using methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay. Cell apoptosis was detected using terminal-deoxynucleoitidyl transferase mediated nick end labeling assay, and autophagy was detected using transmission electron microscopy. Results: HK-2 cells exposed to Urografin for 2 h induced a significant increase in miR-30e-5p. miR-30e-5p had a targeting effect on Beclin1. Moreover, Urografin exposure can enhance cell apoptosis by increasing caspase 3 gene expression and inhibiting autophagy, which was induced by decreased Beclin1 expression regulated by miR-30e-5p, thereby resulting in renal cell injury. Downregulation of miR-30e-5p or upregulation of Beclin1 restored cell vitality by promoting autophagy and suppressing apoptosis in Urografin-treated cells. Conclusions: Urografin increased the expression of miR-30e-5p in HK-2 cells and thus decreased Beclin1 levels to inhibit autophagy, but induced apoptosis, which may be the mechanism for CI-AKI.

scholarly journals Role of 1α,25-Dihydroxyvitamin D3 in Adipogenesis of SGBS Cells: New Insights into Human Preadipocyte Proliferation

2018 ◽  
Vol 48 (1) ◽  
pp. 397-408 ◽  
Author(s):  
Ingrid  Felicidade ◽  
Daniele Sartori ◽  
Susan L.M. Coort ◽  
Simone Cristine Semprebon ◽  
Andressa Megumi Niwa ◽  
...  
Keyword(s):  
Gene Expression ◽  
Vitamin D ◽  
Adipose Tissue ◽  
Lipid Content ◽  
Cell Model ◽  
Adipogenic Differentiation ◽  
Growth Arrest ◽  
Proliferation And Differentiation ◽  
Sgbs Cells

Background/Aims: Compared with non-obese individuals, obese individuals commonly store more vitamin D in adipose tissue. VDR expression in adipose tissue can influence adipogenesis and is therefore a target pathway deserving further study. This study aims to assess the role of 1,25(OH)2D3 in human preadipocyte proliferation and differentiation. Methods: RTCA, MTT, and trypan blue assays were used to assess the effects of 1,25(OH)2D3 on the viability, proliferation, and adipogenic differentiation of SGBS cells. Cell cycle and apoptosis analyses were performed with flow cytometry, triglycerides were quantified, and RT-qPCR was used to assess gene expression. Results: We confirmed that the SGBS cell model is suitable for studying adipogenesis and demonstrated that the differentiation protocol induces cell maturation, thereby increasing the lipid content of cells independently of treatment. 1,25(OH)2D3 treatment had different effects according to the cell stage, indicating different modes of action driving proliferation and differentiation. In preadipocytes, 1,25(OH)2D3 induced G1 growth arrest at both tested concentrations without altering CDKN1A gene expression. Treatment with 100 nM 1,25(OH)2D3 also decreased MTT absorbance and the lipid concentration. Moreover, increased normalized cell index values and decreased metabolic activity were not induced by proliferation or apoptosis. Exposure to 100 nM 1,25(OH)2D3 induced VDR, CEBPA, and CEBPB expression, even in the preadipocyte stage. During adipogenesis, 1,25(OH)2D3 had limited effects on processes such as VDR and PPARG gene expression, but it upregulated CEBPA expression. Conclusions: We demonstrated for the first time that 1,25(OH)2D3 induces changes in preadipocytes, including VDR expression and growth arrest, and increases the lipid content in adipocytes treated for 16 days. Preadipocytes are important cells in adipose tissue homeostasis, and understanding the role of 1,25(OH)2D3 in adipogenesis is a crucial step in ensuring adequate vitamin D supplementation, especially for obese individuals.

scholarly journals Phorbol Ester-Induced Human Cytomegalovirus Major Immediate-Early (MIE) Enhancer Activation through PKC-Delta, CREB, and NF-κB Desilences MIE Gene Expression in Quiescently Infected Human Pluripotent NTera2 Cells

2010 ◽  
Vol 84 (17) ◽  
pp. 8495-8508 ◽  
Author(s):  
Xiaoqiu Liu ◽  
Jinxiang Yuan ◽  
Allen W. Wu ◽  
Patrick W. McGonagill ◽  
Courtney S. Galle ◽  
...  
Keyword(s):  
Gene Expression ◽  
Human Cytomegalovirus ◽  
Binding Sites ◽  
Molecular Mechanisms ◽  
Cell Model ◽  
Gene Activation ◽  
Dominant Negative ◽  
Immediate Early ◽  
Signaling Cascade ◽  
Pkc Delta

ABSTRACT The ways in which human cytomegalovirus (HCMV) major immediate-early (MIE) gene expression breaks silence from latency to initiate the viral replicative cycle are poorly understood. A delineation of the signaling cascades that desilence the HCMV MIE genes during viral quiescence in the human pluripotent N-Tera2 (NT2) cell model provides insight into the molecular mechanisms underlying HCMV reactivation. In this model, we show that phorbol 12-myristate 13-acetate (PMA) immediately activates the expression of HCMV MIE RNA and protein and greatly increases the MIE-positive (MIE+) NT2 cell population density; levels of Oct4 (pluripotent cell marker) and HCMV genome penetration are unchanged. Decreasing PKC-delta activity (pharmacological, dominant-negative, or RNA interference [RNAi] method) attenuates PMA-activated MIE gene expression. MIE gene activation coincides with PKC-delta Thr505 phosphorylation. Mutations in MIE enhancer binding sites for either CREB (cyclic AMP [cAMP] response element [CRE]) or NF-κB (κB) partially block PMA-activated MIE gene expression; the ETS binding site is negligibly involved, and κB does not confer MIE gene activation by vasoactive intestinal peptide (VIP). The PMA response is also partially attenuated by the RNAi-mediated depletion of the CREB or NF-κB subunit RelA or p50; it is not diminished by TORC2 knockdown or accompanied by TORC2 dephosphorylation. Mutations in both CRE and κB fully abolish PMA-activated MIE gene expression. Thus, PMA stimulates a PKC-delta-dependent, TORC2-independent signaling cascade that acts through cellular CREB and NF-κB, as well as their cognate binding sites in the MIE enhancer, to immediately desilence HCMV MIE genes. This signaling cascade is distinctly different from that elicited by VIP.

Cold-induced RNA-binding protein (CIRBP) regulates the expression of Src-associated during mitosis of 68 kDa (Sam68) and extracellular signal-regulated kinases (ERK) during heat stress-induced testicular injury

2020 ◽  
Vol 32 (18) ◽  
pp. 1357
Author(s):  
Chengcheng Xu ◽  
Dandan Ke ◽  
Liping Zou ◽  
Nianyu Li ◽  
Yingying Wang ◽  
...  
Keyword(s):  
Gene Expression ◽  
Heat Stress ◽  
Protein Expression ◽  
Rna Binding ◽  
Cell Model ◽  
Binding Protein ◽  
Rna Binding Protein ◽  
Protein Levels ◽  
Extracellular Signal ◽  
Testicular Injury

In this study, the ability of cold-induced RNA-binding protein (CIRBP) to regulate the expression of Src-associated during mitosis of 68 kDa (Sam68) and extracellular signal-regulated kinases (ERK) in the mouse testis and mouse primary spermatocytes (GC-2spd cell line) before and after heat stress was examined to explore the molecular mechanism by which CIRBP decreases testicular injury. A mouse testicular hyperthermia model, a mouse primary spermatocyte hyperthermia model and a low CIRBP gene-expression cell model were constructed and their relevant parameters were analysed. The mRNA and protein levels of CIRBP and Sam68 were significantly decreased in the 3-h and 12-h testicular heat-stress groups, extracellular signal-regulated kinase 1/2 (ERK1/2) protein expression was not significantly affected but phospho-ERK1/2 protein levels were significantly decreased. GC-2spd cellular heat-stress results showed that the mRNA and protein concentrations of CIRBP and Sam68 were reduced 48h after heat stress. In the low CIRBP gene-expression cell model, CIRBP protein expression was significantly decreased. Sam68 mRNA expression was significantly decreased only at the maximum transfection concentration of 50nM and Sam68 protein expression was not significantly affected. These findings suggest that CIRBP may regulate the expression of Sam68 at the transcriptional level and the expression of phospho-ERK1/2 protein, both of which protect against heat-stress-induced testicular injury in mice.

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