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Redox Biology Jul 2022Osteosarcoma (OS) is a malignant bone tumor that mainly occurs in adolescents. It is accompanied by a high rate of lung metastasis, and high mortality. Recent studies...
Osteosarcoma (OS) is a malignant bone tumor that mainly occurs in adolescents. It is accompanied by a high rate of lung metastasis, and high mortality. Recent studies have suggested the important roles of tripartite motif-containing (TRIM) family proteins in regulating various substrates and signaling pathways in different tumors. However, the detailed functional role of TRIM family proteins in the progression of OS is still unknown and requires further investigations. In this study, we found that tripartite motif-containing 22 (TRIM22) was downregulated in OS tissues and was hence associated with better prognosis. In vitro and in vivo functional analysis demonstrated that TRIM22 inhibits proliferation and metastasis of OS cells. Nuclear factor erythroid 2-related factor 2 (NRF2), a redox regulator, was identified as a novel target for TRIM22. TRIM22 interacts with and accelerates the degradation of NRF2 by inducing its ubiquitination dependent on its E3 ligase activity but independent of Kelch-like ECH-associated protein 1 (KEAP1). Further, a series of gain- and loss-of-function experiments showed that knockdown or overexpression of NRF2 reversed the functions of knockdown or overexpression of TRIM22 in OS. Mechanistically, TRIM22 inhibited OS progression through NRF2-mediated intracellular reactive oxygen species (ROS) imbalance. ROS production was significantly promoted and mitochondrial potential was remarkably inhibited when overexpressing TRIM22, thus activating AMPK/mTOR signaling. Moreover, TRIM22 was also found to inhibit Warburg effect in OS cells. Autophagy activation was found in OS cells which were overexpressed TRIM22, thus leading to autophagic cell death. Treatment with N-Acetylcysteine (NAC), a ROS scavenger or the autophagy inhibitor 3-Methyladenine (3-MA) abolished the decreased malignant phenotypes in TRIM22 overexpressing OS cells. In conclusion, our study indicated that TRIM22 inhibits OS progression by promoting proteasomal degradation of NRF2 independent of KEAP1, thereby activating ROS/AMPK/mTOR/Autophagy signaling that leads to autophagic cell death in OS. Therefore, our findings indicated that targeting TRIM22/NRF2 could be a promising therapeutic target for treating OS.
Topics: AMP-Activated Protein Kinases; Adolescent; Autophagy; Bone Neoplasms; Humans; Kelch-Like ECH-Associated Protein 1; Minor Histocompatibility Antigens; NF-E2-Related Factor 2; Osteosarcoma; Reactive Oxygen Species; Repressor Proteins; TOR Serine-Threonine Kinases; Tripartite Motif Proteins
PubMed: 35636015
DOI: 10.1016/j.redox.2022.102344 -
Cell Death & Disease Jul 2023Hepatic ischemia-reperfusion (I/R) injury, a common clinical complication of liver transplantation, gravely affects patient prognosis. Krüppel-like factors (KLFs)...
Hepatic ischemia-reperfusion (I/R) injury, a common clinical complication of liver transplantation, gravely affects patient prognosis. Krüppel-like factors (KLFs) constitute a family of C2/H2 zinc finger DNA-binding proteins. KLF6, a member of the KLF protein family, plays crucial roles in proliferation, metabolism, inflammation, and injury responses; however, its role in HIR is largely remains unknown. After I/R injury, we found that KLF6 expression in mice and hepatocytes was significantly upregulated. Mice were then subjected to I/R following injection of shKLF6- and KLF6-overexpressing adenovirus through the tail vein. KLF6 deficiency markedly exacerbated liver damage, cell apoptosis, and activation of hepatic inflammatory responses, whereas hepatic overexpression of KLF6 in mice produced the opposite results. In addition, we knocked out or overexpressed KLF6 in AML12 cells before exposing them to a hypoxia-reoxygenation challenge. KLF6 knockout decreased cell viability and increased hepatocyte inflammation, apoptosis, and ROS, whereas KLF6 overexpression had the opposite effects. Mechanistically, KLF6 inhibited the overactivation of autophagy at the initial stage, and the regulatory effect of KLF6 on I/R injury was autophagy-dependent. CHIP-qPCR and luciferase reporter gene assays confirmed that KLF6 bound to the promoter region of Beclin1 and inhibited its transcription. Additionally, KLF6 activated the mTOR/ULK1 pathway. Finally, we performed a retrospective analysis of the clinical data of liver transplantation patients and identified significant associations between KLF6 expression and liver function following liver transplantation. In conclusion, KLF6 inhibited the overactivation of autophagy via transcriptional regulation of Beclin1 and activation of the mTOR/ULK1 pathway, thereby protecting the liver from I/R injury. KLF6 is expected to serve as a biomarker for estimating the severity of I/R injury following liver transplantation.
Topics: Animals; Mice; Autophagy; Beclin-1; Inflammation; Liver; Retrospective Studies; Kruppel-Like Factor 6
PubMed: 37391422
DOI: 10.1038/s41419-023-05872-3 -
Journal of Experimental & Clinical... Oct 2021The zinc transporters Zrt- and Irt-related protein (ZIP/SLC39) are overexpressed in human tumors and correlate with poor prognosis; however, their contributions to...
BACKGROUND
The zinc transporters Zrt- and Irt-related protein (ZIP/SLC39) are overexpressed in human tumors and correlate with poor prognosis; however, their contributions to carcinogenesis and chemoresistance in osteosarcoma (OS) remain unclear.
METHODS
We collected 64 OS patient tissues with (n = 12) or without (n = 52) chemotherapy. The expression levels of ZIP10 were measured by immunohistochemistry and applied to prognostic analysis. ZIP10 was knocked down or overexpressed in OS cell lines to explore its effect on proliferation and chemoresistance. RNA sequencing, quantitative real-time PCR, and western blotting analysis were performed to explore ZIP10-regulated downstream target genes. A xenograft mouse model was established to evaluate the mechanisms by which ZIP10 modulates chemoresistance in OS cells.
RESULTS
The expression of ZIP10 was significantly induced by chemotherapy and highly associated with the clinical outcomes of OS. Knockdown of ZIP10 suppressed OS cell proliferation and chemoresistance. In addition, ZIP10 promoted Zn content-induced cAMP-response element binding protein (CREB) phosphorylation and activation, which are required for integrin α10 (ITGA10) transcription and ITGA10-mediated PI3K/AKT pathway activation. Importantly, ITGA10 stimulated PI3K/AKT signaling but not the classical FAK or SRC pathway. Moreover, overexpression of ZIP10 promoted ITGA10 expression and conferred chemoresistance. Treatment with the CREB inhibitor 666-15 or the PI3K/AKT inhibitor GSK690693 impaired tumor chemoresistance in ZIP10-overexpressing cells. Finally, a xenograft mouse model established by subcutaneous injection of 143B cells confirmed that ZIP10 mediates chemotherapy resistance in OS cells via the ZIP10-ITGA10-PI3K/AKT axis.
CONCLUSIONS
We demonstrate that ZIP10 drives OS proliferation and chemoresistance through ITGA10-mediated activation of the PI3K/AKT pathway, which might serve as a target for OS treatment.
Topics: Animals; Cation Transport Proteins; Cell Line, Tumor; Cell Proliferation; Cyclic AMP Response Element-Binding Protein; Disease Models, Animal; Drug Resistance, Neoplasm; Gene Knockdown Techniques; Heterografts; Humans; Integrin alpha Chains; Mice; Models, Biological; Osteosarcoma; Phosphatidylinositol 3-Kinases; Phosphorylation; Proto-Oncogene Proteins c-akt; Signal Transduction
PubMed: 34706747
DOI: 10.1186/s13046-021-02146-8 -
International Journal of Biological... 2020: The High Mobility Group A1 (HMGA1) proteins, serving as a dynamic regulator of gene transcription and chromatin remodeling, play an influential part in the...
: The High Mobility Group A1 (HMGA1) proteins, serving as a dynamic regulator of gene transcription and chromatin remodeling, play an influential part in the pathological process of a large number of cardiovascular diseases. However, the precise role of HMGA1 in sepsis induced cardiomyopathy (SIC) remains unintelligible. This research was designed to illustrate the effect of HMGA1 involved in SIC. : Cardiomyocyte-specific HMGA1 overexpression was obtained using an adeno-associated virus system with intramyocardial injection in mice heart. The model of SIC in mice was constructed via intraperitoneal injection of lipopolysaccharide (LPS) for 6h. H9c2 rat cardiomyocytes was stimulated with LPS for 12h. HMGA1 expression was upregulated in murine inflammatory hearts as well as LPS stimulated H9c2 cardiomyocytes. HMGA1-overexpressing exhibited aggravated cardiac dysfunction, cardiac inflammation as well as cells apoptosis following LPS treatment both in vivo and experiment. Interestingly, HMGA1 knockdown in H9c2 cardiomyocytes attenuated LPS-induced cardiomyocyte inflammation, but aggravated cell apoptosis. Mechanistically, we found that overexpression of HMGA1 induced increased expression of cyclooxygenase-2 (COX-2). COX-2 inhibitor alleviated the aggravation of inflammation and apoptosis in HMGA1 overexpressed H9c2 cardiomyocytes whereas HMGA1 knockdown induced a reduction in signal transducer and activators of transcription 3 (STAT3) expression. STAT3 agonist reversed HMGA1 silence induced anti-inflammatory effects, while ameliorated cell apoptosis induced by LPS. : In conclusion, our results suggest that overexpression of HMGA1 aggravated cardiomyocytes inflammation and apoptosis by up-regulating COX-2 expression, while silence of HMGA1 expression attenuated inflammation but aggregated cell apoptosis via down-regulation of STAT3.
Topics: Animals; Cardiomyopathies; Cell Line; Cytokines; Gene Expression Regulation; HMGA1a Protein; Inflammation; Lipopolysaccharides; Male; Mice; Mice, Inbred C57BL; Myocarditis; Myocardium; Myocytes, Cardiac; Rats
PubMed: 32398950
DOI: 10.7150/ijbs.39947 -
ACS Nano Apr 2023Integrins expressed on extracellular vesicles (EVs) secreted by various cancers are reported to mediate the organotropism of these EVs. Our previous experiment found...
Integrins expressed on extracellular vesicles (EVs) secreted by various cancers are reported to mediate the organotropism of these EVs. Our previous experiment found that pancreatic tissue of mice with severe cases of acute pancreatitis (SAP) overexpresses several integrins and that serum EVs of these mice (SAP-EVs) can mediate acute lung injury (ALI). It is unclear if SAP-EV express integrins that can promote their accumulation in the lung to promote ALI. Here, we report that SAP-EV overexpress several integrins and that preincubation of SAP-EV with the integrin antagonist peptide HYD-1 markedly attenuates their pulmonary inflammation and disrupt the pulmonary microvascular endothelial cell (PMVEC) barrier. Further, we report that injecting SAP mice with EVs engineered to overexpress two of these integrins (ITGAM and ITGB2) can attenuate the pulmonary accumulation of pancreas-derived EVs and similarly decrease pulmonary inflammation and disruption of the endothelial cell barrier. Based on these findings, we propose that pancreatic EVs can mediate ALI in SAP patients and that this injury response could be attenuated by administering EVs that overexpress ITGAM and/or ITGB2, which is worthy of further study due to the lack of effective therapies for SAP-induced ALI.
Topics: Mice; Animals; Pancreatitis; Acute Disease; Tumor Necrosis Factor-alpha; Acute Lung Injury; Lung; Integrins
PubMed: 37022097
DOI: 10.1021/acsnano.2c12722 -
Cells Sep 2022A previous study found that transmembrane protein 43 (TMEM43) was highly associated with arrhythmogenic right ventricular dysplasia/cardiomyopathy. However, as a...
A previous study found that transmembrane protein 43 (TMEM43) was highly associated with arrhythmogenic right ventricular dysplasia/cardiomyopathy. However, as a transmembrane protein, TMEM43 may be involved in ferroptosis in cardiovascular disease. In this study, we aimed to explore the role of TMEM43 in lipopolysaccharide (LPS)-induced cardiac injury and the underlying mechanism. Mice were injected with LPS (10 mg/kg) for 12 h to generate experimental sepsis. Mice were also subjected to AAV9-shTMEM43 to knock down TMEM43 or AAV9-TMEM43 to overexpress TMEM43 in hearts. H9c2 rat cardiomyocytes were also transfected with Ad-TMEM43 or TMEM43 siRNA to overexpress/knock down TMEM43. As a result, TMEM43 knockdown in hearts deteriorated LPS-induced mouse cardiac injury and dysfunction. LPS increased cardiac ferroptosis as assessed by malonaldehyde (MDA) and cardiac iron density, which were aggravated by TMEM43 knockdown. Moreover, TMEM43 overexpression alleviated LPS-induced cardiac injury, dysfunction, and ferroptosis. In vitro experiments showed that TMEM43 overexpression inhibited LPS-induced lipid peroxidation and cardiomyocyte injury while TMEM43 knockdown aggravated LPS-induced ferroptosis and injury in cardiomyocytes. Mechanistically, LPS increased the expression of P53 and ferritin but decreased the level of Gpx4 and SLC7A11. TMEM43 could inhibit the level of P53 and ferritin enhanced the level of Gpx4 and SLC7A11. Furthermore, ferrostatin-1 (Fer-1), a specific inhibitor of ferroptosis, could protect against LPS-induced cardiac injury and also counteracted the deteriorating effects of TMEM43 silencing in the heart. Based on these findings, we concluded that TMEM43 protects against sepsis-induced cardiac injury via inhibiting ferroptosis in mice. By targeting ferroptosis in cardiomyocytes, TMEM43 may be a therapeutic strategy for preventing sepsis in the future.
Topics: Animals; Ferritins; Ferroptosis; Heart Injuries; Iron; Lipopolysaccharides; Malondialdehyde; Membrane Proteins; Mice; RNA, Small Interfering; Rats; Sepsis; Tumor Suppressor Protein p53
PubMed: 36230956
DOI: 10.3390/cells11192992 -
The International Journal of... Sep 2021Understanding why proteins are overexpressed in cancer is of great interest, as it holds the potential for improved cancer diagnosis and treatment. A noteworthy... (Review)
Review
Understanding why proteins are overexpressed in cancer is of great interest, as it holds the potential for improved cancer diagnosis and treatment. A noteworthy candidate, p21-activated kinase 4 (PAK4), is frequently overexpressed in cancer and a key player in multiple hallmarks of cancer. Here we review findings backing PAK4 overexpression in cancer and motivate PAK4 as a suitable target for the development of cancer therapy.
Topics: Cell Proliferation; Gene Expression Regulation, Neoplastic; Humans; Neoplasms; p21-Activated Kinases
PubMed: 34274498
DOI: 10.1016/j.biocel.2021.106041 -
Free Radical Biology & Medicine Oct 2023Cytochrome b reductase 3 (CYB5R3) activates respiratory metabolism in cellular systems and exerts a prolongevity action in transgenic mice overexpressing this enzyme,...
Cytochrome b reductase 3 (CYB5R3) activates respiratory metabolism in cellular systems and exerts a prolongevity action in transgenic mice overexpressing this enzyme, mimicking some of the beneficial effects of calorie restriction. The aim of our study was to investigate the role of sex on metabolic adaptations elicited by CYB5R3 overexpression, and how key markers related with mitochondrial function are modulated in skeletal muscle, one of the major contributors to resting energy expenditure. Young CYB5R3 transgenic mice did not exhibit the striking adaptations in carbon metabolism previously detected in older animals. CYB5R3 was efficiently overexpressed and targeted to mitochondria in skeletal muscle from transgenic mice regardless sex. Overexpression significantly elevated NADH in both sexes, although differences were not statistically significant for NAD, and increased the abundance of cytochrome c and the fission protein DRP-1 in females but not in males. Moreover, while mitochondrial biogenesis and function markers (as TFAM, NRF-1 and cleaved SIRT3) were markedly upregulated by CYB5R3 overexpression in females, a downregulation was observed in males. Ultrastructural changes were also highlighted, with an increase in the number of mitochondria per surface unit, and in the size of intermyofibrillar mitochondria in transgenic females compared with their wild-type controls. Our results support that CYB5R3 overexpression upregulates markers consistent with enhanced mitochondrial biogenesis and function, and increases mitochondrial abundance in skeletal muscle, producing most of these potentially beneficial actions in females.
Topics: Animals; Female; Male; Mice; Carrier Proteins; Cytochrome-B(5) Reductase; Energy Metabolism; Mice, Transgenic; Mitochondria; Muscle, Skeletal; Sex Factors
PubMed: 37463636
DOI: 10.1016/j.freeradbiomed.2023.07.012 -
Hepatology Communications Aug 2023The role of thioredoxin-interacting protein (TXNIP) in lipopolysaccharide-induced liver injury in mice has been reported, but the underlying mechanisms are poorly...
BACKGROUND
The role of thioredoxin-interacting protein (TXNIP) in lipopolysaccharide-induced liver injury in mice has been reported, but the underlying mechanisms are poorly understood.
METHODS
We overexpressed deubiquitinase in cells overexpressing TXNIP and then detected the level of TXNIP to screen out the deubiquitinase regulating TXNIP; the interaction between TXNIP and deubiquitinase was verified by coimmunoprecipitation. After knockdown of a deubiquitinase and overexpression of TXNIP in Huh7 and HepG2 cells, lipopolysaccharide was used to establish a cellular inflammatory model to explore the role of deubiquitinase and TXNIP in hepatocyte inflammation.
RESULTS
In this study, we discovered that ubiquitin-specific protease 5 (USP5) interacts with TXNIP and stabilizes it through deubiquitylation in Huh-7 and HepG2 cells after treatment with lipopolysaccharide. In lipopolysaccharide-treated Huh-7 and HepG2 cells, USP5 knockdown increased cell viability, reduced apoptosis, and decreased the expression of inflammatory factors, including NLRP3, IL-1β, IL-18, ASC, and procaspase-1. Overexpression of TXNIP reversed the phenotype induced by knockdown USP5.
CONCLUSIONS
In summary, USP5 promotes lipopolysaccharide-induced apoptosis and inflammatory response by stabilizing the TXNIP protein.
Topics: Apoptosis; Deubiquitinating Enzymes; Lipopolysaccharides; NLR Family, Pyrin Domain-Containing 3 Protein; Signal Transduction; Humans; Hep G2 Cells; Endopeptidases; Carrier Proteins
PubMed: 37534934
DOI: 10.1097/HC9.0000000000000193 -
International Journal of Molecular... Apr 2022The fact that overexpression of the yeast Ser/Thr protein phosphatase Ppz1 induces a dramatic halt in cell proliferation was known long ago, but only work in the last... (Review)
Review
The fact that overexpression of the yeast Ser/Thr protein phosphatase Ppz1 induces a dramatic halt in cell proliferation was known long ago, but only work in the last few years has provided insight into the molecular basis for this toxicity. Overexpression of Ppz1 causes abundant changes in gene expression and modifies the phosphorylation state of more than 150 proteins, including key signaling protein kinases such as Hog1 or Snf1. Diverse cellular processes are altered: halt in translation, failure to properly adapt to low glucose supply, acidification of the cytosol, or depletion of intracellular potassium content are a few examples. Therefore, the toxicity derived from an excess of Ppz1 appears to be multifactorial, the characteristic cell growth blockage thus arising from the combination of various altered processes. Notably, overexpression of the Ppz1 regulatory subunit Hal3 fully counteracts the toxic effects of the phosphatase, and this process involves intracellular relocation of the phosphatase to internal membranes.
Topics: Cell Cycle; Phosphoprotein Phosphatases; Phosphorylation; Saccharomyces cerevisiae; Saccharomyces cerevisiae Proteins
PubMed: 35457140
DOI: 10.3390/ijms23084304