scholarly journals SAG/ROC2 E3 ligase regulates skin carcinogenesis by stage-dependent targeting of c-Jun/AP1 and IκB-α/NF-κB

2007 ◽  
Vol 178 (6) ◽  
pp. 1009-1023 ◽  
Author(s):  
Qingyang Gu ◽  
G. Tim Bowden ◽  
Daniel Normolle ◽  
Yi Sun
Keyword(s):  
Early Stage ◽  
Nuclear Factor Κb ◽  
Tumor Formation ◽  
Luciferase Reporter ◽  
Activator Protein 1 ◽  
Cellular Functions ◽  
Accelerated Proliferation ◽  
F Box Protein

Sensitive to apoptosis gene (SAG)/regulator of cullins-2–Skp1-cullin–F-box protein (SCF) E3 ubiquitin ligase regulates cellular functions through ubiquitination and degradation of protein substrates. We report that, when expressed in mouse epidermis driven by the K14 promoter, SAG inhibited TPA-induced c-Jun levels and activator protein-1 (AP-1) activity in both in vitro primary culture, in vivo transgenic mice, and an AP-1– luciferase reporter mouse model. After AP-1 inactivation, epidermal proliferation induced by 7,12-dimethylbenz(a)-anthracene/12-O-tetradecanoylphorbol-13-acetate at the early stage of carcinogenesis was substantially inhibited. Later stage tumor formation was also substantially inhibited with prolonged latency and reduced frequency of tumor formation. Interestingly, SAG expression increased tumor size, not because of accelerated proliferation, but caused by reduced apoptosis resulting, at least in part, from nuclear factor κB (NF-κB) activation. Thus, SAG, in a manner depending on the availability of F-box proteins, demonstrated early-stage suppression of tumor formation by promoting c-Jun degradation, thereby inhibiting AP-1, and later-stage enhancement of tumor growth, by promoting inhibitor of κBα degradation to activate NF-κB and inhibit apoptosis.

scholarly journals Sevoflurane inhibits malignant progression of colorectal cancer via hsa_circ_0000231-mediated miR-622

2021 ◽  
Vol 28 (1) ◽  
Author(s):  
Jingpeng Wang ◽  
Shuyuan Li ◽  
Gaofeng Zhang ◽  
Huihua Han
Keyword(s):  
Colorectal Cancer ◽  
Cell Proliferation ◽  
Cell Apoptosis ◽  
Volatile Anesthetic ◽  
Tumor Formation ◽  
Luciferase Reporter ◽  
Migration And Invasion ◽  
Circular Rnas

Abstract Background Sevoflurane (Sev), a commonly used volatile anesthetic, has been reported to inhibit the process of colorectal cancer (CRC). Circular RNAs (circRNAs) are revealed to participate in the pathogenesis of CRC. This study aims to reveal the mechanism of hsa_circ_0000231 in Sev-mediated CRC progression. Methods The expression of hsa_circ_0000231 and microRNA-622 (miR-622) was detected by quantitative real-time polymerase chain reaction (qRT-PCR). Protein level was determined by western blot analysis. Cell proliferation was investigated by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), cell colony formation and DNA content quantitation assays. Cell apoptosis was detected by Annexin V-fluorescein isothiocyanate and propidium iodide double staining and caspase 3 activity assays. Cell migration and invasion were investigated by wound-healing and transwell invasion assays, respectively. The putative relationship between hsa_circ_0000231 and miR-622 was predicted by circular RNA Interactome online database, and identified by dual-luciferase reporter and RNA immunoprecipitation assays. The impacts of hsa_circ_0000231 on Sev-mediated tumor formation in vivo were presented by in vivo assay. Results Hsa_circ_0000231 expression was upregulated, while miR-622 was downregulated in CRC tissues and cells compared with control groups. Sev treatment decreased hsa_circ_0000231 expression, but increased miR-622 expression in CRC cells. Sev treatment suppressed cell proliferation, migration and invasion, and induced cell apoptosis. Hsa_circ_0000231 overexpression restored Sev-mediated CRC progression in vitro. Additionally, hsa_circ_0000231 acted as a sponge of miR-622, and miR-622 inhibitors reversed the impacts of hsa_circ_0000231 silencing on CRC process. Furthermore, Sev treatment inhibited tumor growth by regulating hsa_circ_0000231 in vivo. Conclusion Hsa_circ_0000231 attenuated Sev-aroused repression impacts on CRC development by sponging miR-622. This findings may provide an appropriate anesthetic protocol for CRC sufferers undergoing surgery.

scholarly journals Periprosthetic Osteolysis: Mechanisms, Prevention and Treatment

2019 ◽  
Vol 8 (12) ◽  
pp. 2091 ◽  
Author(s):  
Stuart B. Goodman ◽  
Jiri Gallo
Keyword(s):  
Nuclear Factor Κb ◽  
Nuclear Factor ◽  
Activator Protein 1 ◽  
Periprosthetic Osteolysis ◽  
Bone Implant ◽  
Joint Replacements ◽  
In Vivo Experiments ◽  
Mechanical Factors

Clinical studies, as well as in vitro and in vivo experiments have demonstrated that byproducts from joint replacements induce an inflammatory reaction that can result in periprosthetic osteolysis (PPOL) and aseptic loosening (AL). Particle-stimulated macrophages and other cells release cytokines, chemokines, and other pro-inflammatory substances that perpetuate chronic inflammation, induce osteoclastic bone resorption and suppress bone formation. Differentiation, maturation, activation, and survival of osteoclasts at the bone–implant interface are under the control of the receptor activator of nuclear factor kappa-Β ligand (RANKL)-dependent pathways, and the transcription factors like nuclear factor κB (NF-κB) and activator protein-1 (AP-1). Mechanical factors such as prosthetic micromotion and oscillations in fluid pressures also contribute to PPOL. The treatment for progressive PPOL is only surgical. In order to mitigate ongoing loss of host bone, a number of non-operative approaches have been proposed. However, except for the use of bisphosphonates in selected cases, none are evidence based. To date, the most successful and effective approach to preventing PPOL is usage of wear-resistant bearing couples in combination with advanced implant designs, reducing the load of metallic and polymer particles. These innovations have significantly decreased the revision rate due to AL and PPOL in the last decade.

scholarly journals Bovine Foamy Virus Transactivator BTas Interacts with Cellular RelB To Enhance Viral Transcription

2010 ◽  
Vol 84 (22) ◽  
pp. 11888-11897 ◽  
Author(s):  
Jian Wang ◽  
Juan Tan ◽  
Hongyan Guo ◽  
Qicheng Zhang ◽  
Rui Jia ◽  
...  
Keyword(s):  
Foamy Virus ◽  
Nuclear Factor Κb ◽  
Luciferase Reporter ◽  
Viral Transcription ◽  
Bovine Foamy Virus ◽  
Intracellular Parasites ◽  
Positive Feedback Circuit ◽  
Cellular Machinery

ABSTRACT Viruses are obligate intracellular parasites that depend on cellular machinery for their efficient transcription and replication. In a previous study we reported that bovine foamy virus (BFV) is able to activate the nuclear factor κB (NF-κB) pathway through the action of its transactivator BTas to enhance viral transcription. However, the mechanism used by NF-κB to enhance BFV transcription remains elusive. To address this question, we employed a yeast two-hybrid assay to screen for BTas-interacting proteins. We found that RelB, a member of NF-κB protein family, interacts with BTas. We confirmed the putative RelB-BTas interaction in vitro and in vivo and identified the protein regions responsible for the RelB-BTas interaction. Using a luciferase reporter assay, we next showed that RelB enhances BFV transcription (BTas-induced long terminal repeat [LTR] transactivation) and that this process requires both the localization of the RelB-BTas interaction in the nucleus and the Rel homology domain of RelB. The knockdown of the cellular endogenous RelB protein using small interfering RNA (siRNA) significantly attenuated BTas-induced LTR transcription. The results of chromatin immunoprecipitation (ChIP) analysis showed that endogenous RelB binds to the viral LTR in BFV-infected cells. Together, these results suggest that BFV engages the RelB protein as a cotransactivator of BTas to enhance viral transcription. In addition, our findings indicate that BFV infection upregulates cellular RelB expression through BTas-induced NF-κB activation. Thus, this study demonstrates the existence of a positive-feedback circuit in which BFV utilizes the host's NF-κB pathway through the RelB protein for efficient viral transcription.

scholarly journals Circ_0001421 facilitates glycolysis and lung cancer development by regulating miR-4677-3p/CDCA3

2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Koudong Zhang ◽  
Hang Hu ◽  
Juan Xu ◽  
Limin Qiu ◽  
Haitao Chen ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Cell Proliferation ◽  
Tumor Progression ◽  
Lactate Production ◽  
Tumor Formation ◽  
Luciferase Reporter ◽  
Circular Rnas ◽  
Glucose Assay

Abstract Background Lung cancer (LC) is a malignant tumor originating in the bronchial mucosa or gland of the lung. Circular RNAs (circRNAs) are proved to be key regulators of tumor progression. However, the regulatory effect of circ_0001421 on lung cancer tumorigenesis remains unclear. Methods The expression levels of circ_0001421, microRNA-4677-3p (miR-4677-3p) and cell division cycle associated 3 (CDCA3) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Methyl thiazolyl tetrazolium (MTT), Transwell and Tumor formation assays were performed to explore the role of circ_0001421 in LC. Glucose consumption and lactate production were examined by a Glucose assay kit and a Lactic Acid assay kit. Western blot was utilized to examine the protein levels of Hexokinase 2 (HK2) and CDCA3. The interaction between miR-4677-3p and circ_0001421 or CDCA3 was confirmed by dual-luciferase reporter assay. Results Circ_0001421 was increased in LC tissues and cells, and knockdown of circ_0001421 repressed cell proliferation, migration, invasion and glycolysis in vitro. Meanwhile, circ_0001421 knockdown inhibited LC tumor growth in vivo. Mechanistically, circ_0001421 could bind to miR-4677-3p, and CDCA3 was a target of miR-4677-3p. Rescue assays manifested that silencing miR-4677-3p or CDCA3 overexpression reversed circ_0001421 knockdown-mediated suppression on cell proliferation, migration, invasion and glycolysis in LC cells. Conclusion Circ_0001421 promoted cell proliferation, migration, invasion and glycolysis in LC by regulating the miR-4677-3p/CDCA3 axis, which providing a new mechanism for LC tumor progression.

scholarly journals Distinct Mutations in IRAK-4 Confer Hyporesponsiveness to Lipopolysaccharide and Interleukin-1 in a Patient with Recurrent Bacterial Infections

2003 ◽  
Vol 198 (4) ◽  
pp. 521-531 ◽  
Author(s):  
Andrei E. Medvedev ◽  
Arnd Lentschat ◽  
Douglas B. Kuhns ◽  
Jorge C.G. Blanco ◽  
Cindy Salkowski ◽  
...  
Keyword(s):  
Bacterial Infections ◽  
Interleukin 1 ◽  
Nuclear Factor Κb ◽  
Kinase Domain ◽  
Compound Heterozygous ◽  
Activator Protein 1 ◽  
Death Domain ◽  
Aseptic Inflammation

We identified previously a patient with recurrent bacterial infections who failed to respond to gram-negative LPS in vivo, and whose leukocytes were profoundly hyporesponsive to LPS and IL-1 in vitro. We now demonstrate that this patient also exhibits deficient responses in a skin blister model of aseptic inflammation. A lack of IL-18 responsiveness, coupled with diminished LPS and/or IL-1–induced nuclear factor–κB and activator protein-1 translocation, p38 phosphorylation, gene expression, and dysregulated IL-1R–associated kinase (IRAK)–1 activity in vitro support the hypothesis that the defect lies within the signaling pathway common to toll-like receptor 4, IL-1R, and IL-18R. This patient expresses a “compound heterozygous” genotype, with a point mutation (C877T in cDNA) and a two-nucleotide, AC deletion (620–621del in cDNA) encoded by distinct alleles of the IRAK-4 gene (GenBank/EMBL/DDBJ accession nos. AF445802 and AY186092). Both mutations encode proteins with an intact death domain, but a truncated kinase domain, thereby precluding expression of full-length IRAK-4 (i.e., a recessive phenotype). When overexpressed in HEK293T cells, neither truncated form augmented endogenous IRAK-1 kinase activity, and both inhibited endogenous IRAK-1 activity modestly. Thus, IRAK-4 is pivotal in the development of a normal inflammatory response initiated by bacterial or nonbacterial insults.

scholarly journals Biological Effect and Mechanism of the miR-23b-3p/ANXA2 Axis in Pancreatic Ductal Adenocarcinoma

2018 ◽  
Vol 50 (3) ◽  
pp. 823-840 ◽  
Author(s):  
Dan-ming Wei ◽  
Yi-wu Dang ◽  
Zhen-bo Feng ◽  
Lu Liang ◽  
Lu Zhang ◽  
...  
Keyword(s):  
Pancreatic Ductal Adenocarcinoma ◽  
Chorioallantoic Membrane ◽  
Tumor Formation ◽  
Ductal Adenocarcinoma ◽  
Luciferase Reporter ◽  
Migration And Invasion ◽  
Chick Chorioallantoic Membrane ◽  
Pancreatic Cancer Cells

Background/Aims: Accumulating evidence strongly suggests that microRNAs (miRNAs) modulate the expression of known tumor suppressor genes and oncogenes. In the present study, we found that the proliferation and invasion ability of pancreatic ductal adenocarcinoma (PDAC) cells were significantly suppressed by the overexpression of miR-23b-3p. In addition, there are miR-23b-3p binding sites in annexin A2 (ANXA2). Here, we investigated whether miR-23b-3p had an impact on the progression and metastasis of PDAC by targeting ANXA2. Methods: Cell proliferation, migration, and invasion, and cell cycle assays were performed to explore the effect of miR-23b-3p on various malignant phenotypes of pancreatic cancer cells. The size of tumors was observed following miR-23b-3p overexpression in an in vivo chick chorioallantoic membrane assay. Dual-luciferase reporter, quantitative real-time PCR, western blot, and immunohistochemical analyses were used to validate the relationship between miR-23b-3p and ANXA2 in vitro. Results: We observed that miR-23b-3p could bind specifically to the 3′ untranslated region of ANXA2 and inhibit its expression. MiR-23b-3p overexpression downregulated the expression of ANXA2 mRNA in PDAC cells and limited the size of tumors or even prevented tumor formation. In addition, there was a negative correlation between miR-23b-3p expression and ANXA2 protein expression in clinical specimens. Conclusion: MiR-23b-3p inhibits the development and progression of PDAC by regulating ANXA2 directly.

scholarly journals Transcriptional Modulator Ifrd1 Regulates Osteoclast Differentiation through Enhancing the NF-κB/NFATc1 Pathway

2016 ◽  
Vol 36 (19) ◽  
pp. 2451-2463 ◽  
Author(s):  
Takashi Iezaki ◽  
Kazuya Fukasawa ◽  
Gyujin Park ◽  
Tetsuhiro Horie ◽  
Takashi Kanayama ◽  
...  
Keyword(s):  
Bone Loss ◽  
Osteoclast Differentiation ◽  
Nuclear Factor Κb ◽  
Bone Diseases ◽  
Nuclear Factor ◽  
Activator Protein 1 ◽  
Bone Homeostasis ◽  
Activated T Cells

Bone homeostasis is maintained by the synergistic actions of bone-resorbing osteoclasts and bone-forming osteoblasts. Here, we show that the transcriptional coactivator/repressor interferon-related developmental regulator 1 (Ifrd1) is expressed in osteoclast lineages and represents a component of the machinery that regulates bone homeostasis. Ifrd1 expression was transcriptionally regulated in preosteoclasts by receptor activator of nuclear factor κB (NF-κB) ligand (RANKL) through activator protein 1. Global deletion of murineIfrd1increased bone formation and decreased bone resorption, leading to a higher bone mass. Deletion ofIfrd1in osteoclast precursors prevented RANKL-induced bone loss, although no bone loss was observed under normal physiological conditions. RANKL-dependent osteoclastogenesis was impairedin vitroinIfrd1-deleted bone marrow macrophages (BMMs).Ifrd1deficiency increased the acetylation of p65 at residues K122 and K123 via the inhibition of histone deacetylase-dependent deacetylation in BMMs. This repressed the NF-κB-dependent transcription of nuclear factor of activated T cells, cytoplasmic 1 (NFATc1), an essential regulator of osteoclastogenesis. These findings suggest that an Ifrd1/NF-κB/NFATc1 axis plays a pivotal role in bone remodelingin vivoand represents a therapeutic target for bone diseases.

scholarly journals In Vivo Interference with Skp1 Function Leads to Genetic Instability and Neoplastic Transformation

2002 ◽  
Vol 22 (23) ◽  
pp. 8375-8387 ◽  
Author(s):  
Roberto Piva ◽  
Jian Liu ◽  
Roberto Chiarle ◽  
Antonello Podda ◽  
Michele Pagano ◽  
...  
Keyword(s):  
T Cell ◽  
Cell Lineage ◽  
Lymphoid Organ ◽  
Cellular Functions ◽  
Multinucleated Cells ◽  
T Cell Lymphomas ◽  
F Box Protein

ABSTRACT Skp1 is involved in a variety of crucial cellular functions, among which the best understood is the formation together with Cul1 of Skp1-cullin-F-box protein ubiquitin ligases. To investigate the role of Skp1, we generated transgenic (Tg) mice expressing a Cul1 deletion mutant (Cul1-N252) able to sequestrate and inactivate Skp1. In vivo interference with Skp1 function through expression of the Cul1-N252 mutant into the T-cell lineage results in lymphoid organ hypoplasia and reduced proliferation. Nonetheless, after a period of latency, Cul1-N252 Tg mice succumb to T-cell lymphomas with high penetrance (>80%). Both T-cell depletion and the neoplastic phenotype of Cul1-N252 Tg mice are largely rescued in Cul1-N252, Skp1 double-Tg mice, indicating that the effects of Cul1-N252 are due to a sequestration of the endogenous Skp1. Analysis of Cul1-N252 lymphomas demonstrates striking karyotype heterogeneity associated with c-myc amplification and c-Myc overexpression. We show that the in vitro expression of the Cul1-N252 mutant causes a pleiotrophic phenotype, which includes the formation of multinucleated cells, centrosome and mitotic spindle abnormalities, and impaired chromosome segregation. Our findings support a crucial role for Skp1 in proper chromosomal segregation, which is required for the maintenance of euploidy and suppression of transformation.

scholarly journals Fosl1 is vital to heart regeneration upon apex resection in adult Xenopus tropicalis

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Hai-Yan Wu ◽  
Yi-Min Zhou ◽  
Zhu-Qin Liao ◽  
Jia-Wen Zhong ◽  
You-Bin Liu ◽  
...  
Keyword(s):  
Early Stage ◽  
Dominant Negative ◽  
Luciferase Reporter ◽  
Heart Regeneration ◽  
Cell Cycle Regulators ◽  
Cardiomyocyte Proliferation ◽  
Neonatal Mice ◽  
Heart Injury

AbstractCardiovascular disease is the leading cause of death in the world due to losing regenerative capacity in the adult heart. Frogs possess remarkable capacities to regenerate multiple organs, including spinal cord, tail, and limb, but the response to heart injury and the underlying molecular mechanism remains largely unclear. Here we demonstrated that cardiomyocyte proliferation greatly contributes to heart regeneration in adult X. tropicalis upon apex resection. Using RNA-seq and qPCR, we found that the expression of Fos-like antigen 1 (Fosl1) was dramatically upregulated in early stage of heart injury. To study Fosl1 function in heart regeneration, its expression was modulated in vitro and in vivo. Overexpression of X. tropicalis Fosl1 significantly promoted the proliferation of cardiomyocyte cell line H9c2. Consistently, endogenous Fosl1 knockdown suppressed the proliferation of H9c2 cells and primary cardiomyocytes isolated from neonatal mice. Taking use of a cardiomyocyte-specific dominant-negative approach, we show that blocking Fosl1 function leads to defects in cardiomyocyte proliferation during X. tropicalis heart regeneration. We further show that knockdown of Fosl1 can suppress the capacity of heart regeneration in neonatal mice, but overexpression of Fosl1 can improve the cardiac function in adult mouse upon myocardium infarction. Co-immunoprecipitation, luciferase reporter, and ChIP analysis reveal that Fosl1 interacts with JunB and promotes the expression of Cyclin-T1 (Ccnt1) during heart regeneration. In conclusion, we demonstrated that Fosl1 plays an essential role in cardiomyocyte proliferation and heart regeneration in vertebrates, at least in part, through interaction with JunB, thereby promoting expression of cell cycle regulators including Ccnt1.

scholarly journals Real-Time Monitoring of Nuclear Factor κB Activity in Cultured Cells and in Animal Models

2009 ◽  
Vol 8 (5) ◽  
pp. 7290.2009.00026 ◽  
Author(s):  
Christian E. Badr ◽  
Johanna M. Niers ◽  
Lee-Ann Tjon-Kon-Fat ◽  
David P. Noske ◽  
Thomas Wurdinger ◽  
...  
Keyword(s):  
Real Time ◽  
Cultured Cells ◽  
Tumor Development ◽  
Nuclear Factor Κb ◽  
Tumor Formation ◽  
Nuclear Factor ◽  
Reporter System ◽  
Human Disorders

Nuclear factor κB (NF-κB) is a transcription factor that plays a major role in many human disorders, including immune diseases and cancer. We designed a reporter system based on NF-κB responsive promoter elements driving expression of the secreted Gaussia princeps luciferase (Gluc). We show that this bioluminescent reporter is a highly sensitive tool for noninvasive monitoring of the kinetics of NF-κB activation and inhibition over time, both in conditioned medium of cultured cells and in the blood and urine of animals. NF-κB activation was successfully monitored in real time in endothelial cells in response to tumor angiogenic signaling, as well as in monocytes in response to inflammation. Further, we demonstrated dual blood monitoring of both NF-κB activation during tumor development as correlated to tumor formation using the NF-κB Gluc reporter, as well as the secreted alkaline phosphatase reporter. This NF-κB reporter system provides a powerful tool for monitoring NF-κB activity in real time in vitro and in vivo.

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