Role of the Nrf2-Mediated Signaling Pathway as a Negative Regulator of Inflammation: Implications for the Impact of Particulate Pollutants on Asthma

2006 ◽  
Vol 8 (1-2) ◽  
pp. 88-98 ◽  
Author(s):  
Ning Li ◽  
Andre E. Nel
Blood ◽  
2006 ◽  
Vol 107 (12) ◽  
pp. 4589-4596 ◽  
Author(s):  
Mei Dong ◽  
Gerard C. Blobe

AbstractThe transforming growth factor-β (TGF-β) signaling pathway is an essential regulator of cellular processes, including proliferation, differentiation, migration, and cell survival. During hematopoiesis, the TGF-β signaling pathway is a potent negative regulator of proliferation while stimulating differentiation and apoptosis when appropriate. In hematologic malignancies, including leukemias, myeloproliferative disorders, lymphomas, and multiple myeloma, resistance to these homeostatic effects of TGF-β develops. Mechanisms for this resistance include mutation or deletion of members of the TGF-β signaling pathway and disruption of the pathway by oncoproteins. These alterations define a tumor suppressor role for the TGF-β pathway in human hematologic malignancies. On the other hand, elevated levels of TGF-β can promote myelofibrosis and the pathogenesis of some hematologic malignancies through their effects on the stroma and immune system. Advances in the TGF-β signaling field should enable targeting of the TGF-β signaling pathway for the treatment of hematologic malignancies.


2021 ◽  
Vol 11 ◽  
Author(s):  
Yinghui Hong ◽  
Mingliang Ye ◽  
Fan Wang ◽  
Jun Fang ◽  
Chun Wang ◽  
...  

BackgroundHepatocellular carcinoma (HCC) remains a major global health burden due to its high prevalence and mortality. Emerging evidence reveals that microRNA (miRNA) plays a vital role in cancer pathogenesis and is widely involved in the regulation of signaling pathways via their targeting of downstream genes. MiR-21-3p, a liver-enriched miRNA, and SMAD7, the negative regulator of the TGF-β signaling pathway, likely exert a vital influence on HCC progression.AimsHere, we explore the role of the miR-21-3p-SMAD7/YAP1 axis on HCC pathogenesis.MethodsMiRNA microarray analysis was performed for miRNA screening. The dual-luciferase assay was adopted for target verification. Expression of miRNA and related genes were quantified via qRT-PCR, western blotting, and immunohistochemical staining. Flow cytometry and the transwell migration assay were used to detail cell apoptosis, invasion and metastases. Rat models were established to explore the role of the miR-21-3p-SMAD7/YAP1 axis in hepatocarcinogenesis. Bioinformatics analysis was conducted for exploring genes of clinical significance.ResultsMiR-21-3p levels were found to be significantly elevated in hepatocellular carcinoma and indicate poor overall survival. High miR-21-3p levels were associated with advanced tumor stages (P = 0.029), in particular T staging (P = 0.026). Low SMAD7/high YAP1 levels were confirmed in both HCC and rat models with advanced liver fibrosis and cirrhosis. Besides, SMAD7 was demonstrated to be the direct target of miR-21-3p. The effect of MiR-21-3p on tumor phenotypes and YAP1 upregulation could be partly reversed via the restoration of SMAD7 expression in HCC cell lines. Overexpression of YAP1 after miR-21-3p upregulation promoted expression of nuclear transcription effector connective tissue growth factor. Co-survival analysis indicated that lower miR-21-3p/higher SMAD7 (P = 0.0494) and lower miR-21-3p/lower YAP1 (P = 0.0379) group patients had better overall survival rates. Gene Set Variation Analysis revealed that gene sets related to miR-21-3p and SMAD7 were significantly associated with the TGF-β signaling pathway in HCC.ConclusionMiR-21-3p promotes migration and invasion of HCC cells and upregulation of YAP1 expression via direct inhibition of SMAD7, underscoring a major epigenetic mechanism in the pathogenesis of HCC.


2006 ◽  
Vol 292 (2) ◽  
pp. 344-357 ◽  
Author(s):  
Eunjoo Park ◽  
Gun-Hwa Kim ◽  
Sun-Cheol Choi ◽  
Jin-Kwan Han

2013 ◽  
Vol 9 (6) ◽  
pp. e1003416 ◽  
Author(s):  
Martin Baril ◽  
Salwa Es-Saad ◽  
Laurent Chatel-Chaix ◽  
Karin Fink ◽  
Tram Pham ◽  
...  

2021 ◽  
Vol 23 (4) ◽  
pp. 775-780
Author(s):  
A. S. Kulakova ◽  
I. A. Snimshchikova ◽  
M. O. Plotnikova

The complexity of the adipogenesis mechanism results from the impact of multiple cues, among which an important place is held by the components of the Wnt signaling pathway. The search for potential markers of the development of diseases related to obesity aroused an interest in the study of GSK-3 (glycogen synthase kinase), β-catenin. GSK-3β is an intracellular serine / threonine kinase found in the cytoplasm, nucleus, mitochondria, synthesized in all body tissues and involved in regulating metabolic processes, cell proliferation, apoptosis etc. The first of the discovered functions of GSK-3β was the regulation of glycogen synthesis. Active GSK-3β phosphorylates and thereby inhibits glycogen synthase. As a result of the insulin binding to the cell receptor via inositol-3-phosphate, protein kinase B (Akt1) is activated, which, in turn, phosphorylates and inhibits GSK-3β. In addition, GSK-3β is involved in the regulating glucose metabolism. The most important function of GSK-3β is the inhibition of the β-catenin protein. In a resting cell, GSK-3β in complex with the APC and Axin proteins binds and phosphorylates the β-catenin transcription factor, which leads to its ubiquitination and degradation. When Wnt proteins act on the cell, the Dvl protein is activated, which, by binding to GSK-3β, releases β-catenin, preventing its degradation, however, the role of GSK3α/β in the adipocyte inflammatory response has not yet been fully investigated, therefore it seems promising to study the role of GSK-3 in the Wnt/β-catenin signaling pathway in obesityThe aim of the study was to assess the activity of the components of the Wnt signaling pathway in obese patients by measuring the serum level of GSK-3 and β-catenin. There were enrolled 32 patients with progressive forms of I-III degree obesity in the absence of diabetes mellitus. The concentration of serum GSK-3α, GSK-3β, and β-catenin was measured by enzyme-linked immunoassay. Data are presented as absolute and relative (%) number of patients; arithmetic mean; medians, 1 and 3 quartiles – Ме (Q0.25-Q0.75). Obese patients contained a 7.5-fold increased serum level of GSK-3α (785 (371-1317.5) pg/ml) compared to healthy individuals 105 (102.5-110) pg/ml, (p < 0.001), paralleled with increased amount of GSK-3β, which level in obese patients was 295 (190-695) pg/ml, which is by 18.3% higher than those in healthy individuals 241 (218.75-287.5) pg/ml, p = 0.111. Amount of GSK-3 depending on the degree of obesity tended to increase, most often coupled to decreased β-catenin level which is consistent with the literature data and can be considered as a prognostic criterion for the course of pathological processes in obesity. 


2018 ◽  
Vol 5 (suppl_1) ◽  
pp. S254-S255
Author(s):  
Thomas McConville ◽  
Marla Giddins ◽  
Nenad Macesic ◽  
Anne-Catrin Uhlemann

Abstract Background Polymyxin resistance (PR) threatens the mainstay of therapy for carbapenem-resistant Enterobacteriaceae (CRE) infections. While mgrB disruption accounts for most cases of PR, missense mutations in crrB have been proposed as an alternative pathway for PR through PmrA/B/C upregulation of the pmrHFIJKLM operon. It remains unknown if CrrB acts as a positive or negative regulator on its downstream targets. Methods We assembled a CRISPR-Cas9 system for gene knockouts (KO) in CRE K. pneumoniae (CRKP) using zeocin as a selectable marker. We chose a polymyxin susceptible (PS) and a PR isolate with a missense mutation in crrB (L87V) (NR5337 and NR5083, respectively) for KO. Isolates were transformed with a crrB KO plasmid, grown with zeocin selection, induced with arabinose, and plated on low-salt LB-zeocin/arabinose. KOs were confirmed via PCR and Sanger sequencing. Polymyxin susceptibility was performed with broth-microdilution. Gene expression was determined by qRT-PCR of cDNA extracts. Results Colistin MIC following crrB KO of NR5337 (PS) remained unchanged. In contrast, crrB KO of NR5083 (PR), decreased polymyxin MIC (MIC &gt;128 to 1.0 μg/mL). qRT-PCR of NR5083 did not show increased expression of pmrA/C, nor pmrK. NR5083 ^crrB showed a small decrease in phoQ expression, compared with NR5083, but similar expression of phoP, pmrA/C and pmrK (Table 1). Conclusion Polymyxin MIC decreased &gt;128 fold after crrB KO in a PR isolate, but colistin MIC remained unchanged after KO in a PS isolate. CrrB mutations in PR isolates may confer a gain of function with CrrB acting as a positive regulator on its downstream targets. Contrary to previous literature, no upregulation of pmrA/C and pmrHFIJKLM was detected. Differences in crrB mutations or clonal background may explain this finding. CRISPR-Cas9 may serve as a reliable system for genetic manipulation of CRKP. Further data on the impact of individual crrB missense mutations are needed. Disclosures A. C. Uhlemann, Merck: Investigator, Grant recipient.


2016 ◽  
Vol 113 (19) ◽  
pp. 5453-5458 ◽  
Author(s):  
Wafa Bouaziz ◽  
Johanna Sigaux ◽  
Dominique Modrowski ◽  
Claire-Sophie Devignes ◽  
Thomas Funck-Brentano ◽  
...  

Low oxygen tension (hypoxia) regulates chondrocyte differentiation and metabolism. Hypoxia-inducible factor 1α (HIF1α) is a crucial hypoxic factor for chondrocyte growth and survival during development. The major metalloproteinase matrix metalloproteinase 13 (MMP13) is also associated with chondrocyte hypertrophy in adult articular cartilage, the lack of which protects from cartilage degradation and osteoarthritis (OA) in mice. MMP13 is up-regulated by the Wnt/β-catenin signaling, a pathway involved in chondrocyte catabolism and OA. We studied the role of HIF1α in regulating Wnt signaling in cartilage and OA. We used mice with conditional knockout of Hif1α (∆Hif1αchon) with joint instability. Specific loss of HIF1α exacerbated MMP13 expression and cartilage destruction. Analysis of Wnt signaling in hypoxic chondrocytes showed that HIF1α lowered transcription factor 4 (TCF4)–β-catenin transcriptional activity and inhibited MMP13 expression. Indeed, HIF1α interacting with β-catenin displaced TCF4 from MMP13 regulatory sequences. Finally, ΔHif1αchon mice with OA that were injected intraarticularly with PKF118-310, an inhibitor of TCF4–β-catenin interaction, showed less cartilage degradation and reduced MMP13 expression in cartilage. Therefore, HIF1α–β-catenin interaction is a negative regulator of Wnt signaling and MMP13 transcription, thus reducing catabolism in OA. Our study contributes to the understanding of the role of HIF1α in OA and highlights the HIF1α–β-catenin interaction, thus providing new insights into the impact of hypoxia in articular cartilage.


2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Emmanuel N. Kontomanolis ◽  
Sofia Kalagasidou ◽  
Stamatia Pouliliou ◽  
Xanthoula Anthoulaki ◽  
Nikolaos Georgiou ◽  
...  

Objective. Notch signaling pathway is a vital parameter of the mammalian vascular system. In this review, the authors summarize the current knowledge about the impact of the Notch signaling pathway in breast cancer progression and the therapeutic role of Notch’s inhibition.Methods. The available literature in MEDLINE, PubMed, and Scopus, regarding the role of the Notch pathway in breast cancer progression was searched for related articles from about 1973 to 2017 including terms such as “Notch,” “Breast Cancer,” and “Angiogenesis.”Results. Notch signaling controls the differentiation of breast epithelial cells during normal development. Studies confirm that the Notch pathway has a major participation in breast cancer progression through overexpression and/or abnormal genetic type expression of the notch receptors and ligands that determine angiogenesis. The cross-talk of Notch and estrogens, the effect of Notch in breast cancer stem cells formation, and the dependable Notch overexpression during breast tumorigenesis have been studied enough and undoubtedly linked to breast cancer development. The already applied therapeutic inhibition of Notch for breast cancer can drastically change the course of the disease.Conclusion. Current data prove that Notch pathway has a major participation and multiple roles during breast tumor progression. Inhibition of Notch receptors and ligands provides innovative therapeutic results and could become the therapy of choice in the next few years, even though further research is needed to reach safe conclusions.


2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Lizhang Han ◽  
Zhonggang Li ◽  
Yuquan Jiang ◽  
Zheng Jiang ◽  
Ling Tang

Abstract Background Glioblastoma has been seen as the most common malignancy of brain tumor. Emerging reports has claimed that SNHG29 (LRRC75A-AS1) was involved in several biological processes via modulation of signaling pathway, and served as an malignant facilitatorin osteosarcoma. However, the specific role of SNHG29 in glioblastoma remains unknown. Methods RT-qPCR and microarray were operated to measure genes expression. Western blot was performed to examine protein expression. CCK-8 and colony formation assays were used to evaluate cell proliferation. Cell migration was tested by transwell assay. Nuclear-cytoplasmic fractionation was conducted to locate SNHG29. The binding capacity of miR-223-3p to SNHG29 or CTNND1 3′UTR was verified by RIP and luciferase reporter assay. Results SNHG29 presented high expression in glioblastoma to boost cell proliferation, migration and EMT process. In addition, miR-223-3p was validated to bind with SNHG29 after prediction and screening. Furthermore, miR-223-3p was proved to be a negative regulator for its target CTNND1. Then, the inhibition on cell proliferation, migration and EMT process resulted from SNHG29 knockdown was recovered by CTNND1 overexpression. At last, the inhibitive impacts on cell proliferation, migration and EMT process of CTNND1 deficiency was abrogated by LiCl. Conclusions In conclusion, SNHG29 regulates miR-223-3p/CTNND1 axis to promote glioblastoma progression via Wnt/β-catenin signaling pathway, offering a potential therapeutic point for glioblastoma patients.


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