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International Journal of Cancer Sep 2023Mammalian target of rapamycin (mTOR) is a central regulator of mammalian metabolism and physiology. Aberrant hyperactivation of the mTOR pathway promotes tumor growth...
Mammalian target of rapamycin (mTOR) is a central regulator of mammalian metabolism and physiology. Aberrant hyperactivation of the mTOR pathway promotes tumor growth and metastasis, and can also promote tumor resistance to chemotherapy and cancer drugs; this makes mTOR an attractive cancer therapeutic target. mTOR inhibitors have been approved to treat cancer; however, the mechanisms underlying drug sensitivity remain poorly understood. Here, whole exome sequencing of three chromophobe renal cell carcinoma (chRCC) patients with exceptional mTOR inhibitor sensitivity revealed that all three patients shared somatic mutations in the deubiquitinase gene USP9X. The clonal characteristics of the mutations, which were amassed by studying multiple patients' primary and metastatic samples from various years, together with the low USP9X mutation rate in unselected chRCC series, reinforced a causal link between USP9X and mTOR inhibitor sensitivity. Rapamycin treatment of USP9X-depleted HeLa and renal cancer 786-O cells, along with the pharmacological inhibition of USP9X, confirmed that this protein plays a role in patients' sensitivity to mTOR inhibitors. USP9X was not found to exert a direct effect on mTORC1, but subsequent ubiquitylome analyses identified p62 as a direct USP9X target. Increased p62 ubiquitination and the augmented rapamycin effect upon bortezomib treatment, together with the results of p62 and LC3 immunofluorescence assays, suggested that dysregulated autophagy in USP9X-depleted cells can have a synergistic effect with mTOR inhibitors. In summary, we show that USP9X constitutes a potential novel marker of sensitivity to mTOR inhibitors in chRCC patients, and represents a clinical strategy for increasing the sensitivity to these drugs.
Topics: Humans; Carcinoma, Renal Cell; Cell Line, Tumor; Deubiquitinating Enzymes; Kidney Neoplasms; MTOR Inhibitors; Sirolimus; TOR Serine-Threonine Kinases; Ubiquitin Thiolesterase
PubMed: 37260183
DOI: 10.1002/ijc.34575 -
The FEBS Journal Dec 2023Cells respond to invading pathogens and danger signals from the environment by adapting gene expression to meet the need for protective effector molecules. While this... (Review)
Review
Cells respond to invading pathogens and danger signals from the environment by adapting gene expression to meet the need for protective effector molecules. While this innate immune response is required for the cell and the organism to recover, excess immune activation may lead to loss of homeostasis, thereby promoting chronic inflammation and cancer progression. The molecular basis of innate immune defence is comprised of factors promoting survival and proliferation, such as cytokines, antimicrobial peptides and anti-apoptotic proteins. As the molecular mechanisms regulating innate immune responses are conserved through evolution, the fruit fly Drosophila melanogaster serves as a convenient, affordable and ethical model organism to enhance understanding of immune signalling. Fly immunity against bacterial infection is built up by both cellular and humoral responses, where the latter is regulated by the Imd and Toll pathways activating NF-κB transcription factors Relish, Dorsal and Dif, as well as JNK activation and JAK/STAT signalling. As in mammals, the Drosophila innate immune signalling pathways are characterised by ubiquitination of signalling molecules followed by ubiquitin receptors binding to the ubiquitin chains, as well as by rapid changes in protein levels by ubiquitin-mediated targeted proteasomal and lysosomal degradation. In this review, we summarise the molecular signalling pathways regulating immune responses to pathogen infection in Drosophila, with a focus on ubiquitin-dependent control of innate immunity and inflammatory signalling.
PubMed: 38069549
DOI: 10.1111/febs.17028 -
Cell Death & Disease Jan 2024Prostate cancer (PCa) is one of the most common malignancy in men. However, the molecular mechanism of its pathogenesis has not yet been elucidated. In this study, we...
Prostate cancer (PCa) is one of the most common malignancy in men. However, the molecular mechanism of its pathogenesis has not yet been elucidated. In this study, we demonstrated that CYLD, a novel deubiquitinating enzyme, impeded PCa development and progression via tumor suppression. First, we found that CYLD was downregulated in PCa tissues, and its expression was inversely correlated with pathological grade and clinical stage. Moreover, we discovered that CYLD inhibited tumor cell proliferation and enhanced the sensitivity to cell ferroptosis in PCa in vitro and in vivo, respectively. Mechanistically, we demonstrated that CYLD suppressed the ubiquitination of YAP protein, then promoted ACSL4 and TFRC mRNA transcription. Then, we demonstrated that CYLD could enhance the sensitivity of PCa xenografts to ferroptosis in vivo. Furthermore, we discovered for the first time that there was a positive correlation between CYLD expression and ACSL4 or TFRC expression in human PCa specimens. The results of this study suggested that CYLD acted as a tumor suppressor gene in PCa and promoted cell ferroptosis through Hippo/YAP signaling.
Topics: Humans; Male; Cell Proliferation; Deubiquitinating Enzyme CYLD; Ferroptosis; Heterografts; Prostate; Prostatic Neoplasms
PubMed: 38246916
DOI: 10.1038/s41419-024-06464-5 -
Biomedicine & Pharmacotherapy =... Apr 2024Deubiquitination, a post-translational modification regulated by deubiquitinases, is essential for cancer initiation and progression. Ubiquitin-specific proteases (USPs)... (Review)
Review
Deubiquitination, a post-translational modification regulated by deubiquitinases, is essential for cancer initiation and progression. Ubiquitin-specific proteases (USPs) are essential elements of the deubiquitinase family, and are overexpressed in gastric cancer (GC). Through the regulation of several signaling pathways, such as Wnt/β-Catenin and nuclear factor-κB signaling, and the promotion of the expression of deubiquitination- and stabilization-associated proteins, USPs promote the proliferation, metastasis, invasion, and epithelial-mesenchymal transition of GC. In addition, the expression of USPs is closely related to clinicopathological features, patient prognosis, and chemotherapy resistance. USPs therefore could be used as prognostic biomarkers. USP targeting small molecule inhibitors have demonstrated strong anticancer activity. However, they have not yet been tested in the clinic. This article provides an overview of the latest fundamental research on USPs in GC, aiming to enhance the understanding of how USPs contribute to GC progression, and identifying possible targets for GC treatment to improve patient survival.
Topics: Humans; Stomach Neoplasms; Ubiquitin-Specific Proteases; Signal Transduction; Wnt Signaling Pathway; Cell Line, Tumor; Gene Expression Regulation, Neoplastic; Epithelial-Mesenchymal Transition; Cell Proliferation
PubMed: 38401523
DOI: 10.1016/j.biopha.2024.116323 -
Medical Oncology (Northwood, London,... Dec 2023Cisplatin-based chemotherapy is the main treatment option for advanced or metastatic esophageal squamous cell carcinoma (ESCC). However, most ESCC patients develop drug...
Cisplatin-based chemotherapy is the main treatment option for advanced or metastatic esophageal squamous cell carcinoma (ESCC). However, most ESCC patients develop drug resistance within 2 years after receiving cisplatin chemotherapy. Ubiquitin-specific protease 10 (USP10) is abnormally expressed in a variety of cancers, but the mechanistic roles of USP10 in ESCC are still obscure. Here, the effects of USP10 on the migration and cisplatin resistance of ESCC in vivo and in vitro and the underlying mechanisms have been investigated by bioinformatics analysis, RT-PCR, western blotting, immunoprecipitation, immunohistochemistry, cell migration and MTS cell proliferation assays, deubiquitination assay, and mouse tail vein injection model. USP10 was significantly up-regulated in ESCC tissues compared with adjacent normal tissues in both public databases and clinical samples and was closely associated with overall survival. Subsequent results revealed that USP10 contributed to the migration and cisplatin resistance of ESCC cells, while knocking down USP10 in cisplatin-resistant cells exhibited opposite effects in vitro and in vivo. Further Co-IP experiments showed that integrin β1 and YAP might be targets for USP10 deubiquitination. Moreover, deficiency of USP10 significantly inhibited the migrative and chemo-resistant abilities of ESCC cells, which could be majorly reversed by integrin β1 or YAP reconstitution. Altogether, USP10 was required for migration and cisplatin resistance in ESCC through deubiquinating and stabilizing integrin β1/YAP, highlighting that inhibition of USP10 may be a potential therapeutic strategy for ESCC.
Topics: Animals; Mice; Humans; Esophageal Squamous Cell Carcinoma; Cisplatin; Esophageal Neoplasms; Integrin beta1; Cell Movement; Disease Models, Animal; Ubiquitin Thiolesterase
PubMed: 38150085
DOI: 10.1007/s12032-023-02272-7 -
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 -
PLoS Pathogens Jul 2023Deubiquitinating enzymes (DUBs) regulate antiviral immune response through targeting DNA sensor signaling pathway members. As one of the DNA sensors, interferon (IFN)-γ...
Deubiquitinating enzymes (DUBs) regulate antiviral immune response through targeting DNA sensor signaling pathway members. As one of the DNA sensors, interferon (IFN)-γ inducible protein 16 (IFI16) play a major role in response to virus infections through activating the canonical STING/TBK-1/IRF3 signaling pathway. Only a few studies discuss the function of DUBs in IFI16-mediated antiviral response. Ubiquitin-specific protease 12 (USP12), which is one of the major members of the USP family, participates in various biological functions. However, whether USP12 regulates the nucleic acid sensor to modulate antiviral immune responses has not yet been elucidated. In this study, we found that knockout or knockdown of USP12 impaired the HSV-1-induced expressions of IFN-β, CCL-5, IL-6, and downstream interferon-stimulated genes (ISGs). Moreover, USP12 deficiency increased HSV-1 replication and host susceptibility to HSV-1 infection. Mechanistically, USP12 inhibited the proteasome-dependent degradation of IFI16 through its deubiquitinase activity, thereby maintaining IFI16 stability and promoting IFI16-STING-IRF3- and p65-mediated antiviral signaling. Overall, our findings demonstrate an essential role of USP12 in DNA-sensing signaling and contribute to the understanding of deubiquitination-mediated regulation of innate antiviral responses.
Topics: Humans; Phosphoproteins; Herpesvirus 1, Human; Herpes Simplex; Interferons; Antiviral Agents; Immunity, Innate; Ubiquitin Thiolesterase; Nuclear Proteins
PubMed: 37410794
DOI: 10.1371/journal.ppat.1011480 -
Clinical and Translational Medicine Sep 2023Triple-negative breast cancer (TNBC), a heterogeneous subtype of breast cancer (BC), had poor prognosis. Endoplasmic reticulum (ER) stress was responsible for cellular...
BACKGROUND
Triple-negative breast cancer (TNBC), a heterogeneous subtype of breast cancer (BC), had poor prognosis. Endoplasmic reticulum (ER) stress was responsible for cellular processes and played a crucial role in the cell function. ER stress is a complex and dynamic process that can induce abnormal apoptosis and death. However, the underlying mechanism of ER stress involved in TNBC is not well defined.
METHODS
We identified ubiquitin-specific protease 19 (USP19) as a TNBC negative regulator for further investigation. The effects of USP19 on BC proliferation were assessed in vitro using proliferation test and cell-cycle assays, while the effects in vivo were examined using a mouse tumorigenicity model. Through in vitro flow cytometric analyses and in vivo TUNEL assays, cell apoptosis was assessed. Proteomics was used to examine the proteins that interact with USP19.
RESULTS
Multiple in vitro and in vivo tests showed that USP19 decreases TNBC cell growth while increasing apoptosis. Then, we demonstrated that USP19 interacts with deubiquitinates and subsequently stabilises family molecular chaperone regulator 6 (BAG6). BAG6 can boost B-cell lymphoma 2 (BCL2) ubiquitination and degradation, thereby raising ER calcium (Ca ) levels and causing ER stress. We also found that the N -methyladenosine (m A) "writer" methyltransferase-like 14 (METTL14) increased global m A modification.
CONCLUSIONS
Our study reveals that USP19 elevates the intracellular Ca concentration to alter ER stress via regulation of BAG6 and BCL2 stability and may be a viable therapeutic target for TNBC therapy.
Topics: Humans; Animals; Calcium; Triple Negative Breast Neoplasms; Endoplasmic Reticulum Stress; Disease Models, Animal; Deubiquitinating Enzymes; Proto-Oncogene Proteins c-bcl-2; Molecular Chaperones; Endopeptidases
PubMed: 37700495
DOI: 10.1002/ctm2.1398 -
International Journal of Biological... Aug 2023Osteoarthritis (OA) is the most common age-related joint disorder with no effective therapy, and its specific pathological mechanism remains to be fully clarified....
Osteoarthritis (OA) is the most common age-related joint disorder with no effective therapy, and its specific pathological mechanism remains to be fully clarified. Adhesion-regulating molecule 1 (ADRM1) has been proven to be involved in OA progression as a favorable gene. However, the exact mechanism of ADRM1 involved in OA were unknown. Here, we showed that the ADRM1 expression decreased in human OA cartilage, destabilization of the medial meniscus (DMM)-induced mouse OA cartilage, and interleukin (IL)-1β-induced primary mouse articular chondrocytes. Global knockout (KO) ADRM1 in cartilage or ADRM1 inhibitor (RA190) could accelerate the disorders of extracellular matrix (ECM) homeostasis, thereby accelerated DMM-induced cartilage degeneration, whereas overexpression of ADRM1 protected mice from DMM-induced OA development by maintaining the homeostasis of articular cartilage. The molecular mechanism study revealed that ADRM1 could upregulate ubiquitin carboxy-terminal hydrolase 37 (UCH37) expression and bind to UCH37 to activate its deubiquitination activity. Subsequently, increased and activated UCH37 enhanced activin receptor-like kinase 5 (ALK5) deubiquitination to stabilize ALK5 expression, thereby maintaining ECM homeostasis and attenuating cartilage degeneration. These findings indicated that ADRM1 could attenuate cartilage degeneration via enhancing UCH37-mediated ALK5 deubiquitination. Overexpression of ADRM1 in OA cartilage may provide a promising OA therapeutic strategy.
Topics: Humans; Mice; Animals; Receptor, Transforming Growth Factor-beta Type I; Ubiquitin Thiolesterase; Chondrocytes; Cartilage, Articular; Osteoarthritis; Extracellular Matrix; Intracellular Signaling Peptides and Proteins
PubMed: 37406898
DOI: 10.1016/j.ijbiomac.2023.125670 -
Frontiers in Immunology 2024Cardiovascular diseases (CVDs) are multifactorial chronic diseases and have the highest rates of morbidity and mortality worldwide. The ubiquitin-proteasome system (UPS)... (Review)
Review
Cardiovascular diseases (CVDs) are multifactorial chronic diseases and have the highest rates of morbidity and mortality worldwide. The ubiquitin-proteasome system (UPS) plays a crucial role in posttranslational modification and quality control of proteins, maintaining intracellular homeostasis via degradation of misfolded, short-lived, or nonfunctional regulatory proteins. Noncoding RNAs (ncRNAs, such as microRNAs, long noncoding RNAs, circular RNAs and small interfering RNAs) serve as epigenetic factors and directly or indirectly participate in various physiological and pathological processes. NcRNAs that regulate ubiquitination or are regulated by the UPS are involved in the execution of target protein stability. The cross-linked relationship between the UPS, ncRNAs and CVDs has drawn researchers' attention. Herein, we provide an update on recent developments and perspectives on how the crosstalk of the UPS and ncRNAs affects the pathological mechanisms of CVDs, particularly myocardial ischemia/reperfusion injury, myocardial infarction, cardiomyopathy, heart failure, atherosclerosis, hypertension, and ischemic stroke. In addition, we further envision that RNA interference or ncRNA mimics or inhibitors targeting the UPS can potentially be used as therapeutic tools and strategies.
Topics: Humans; Cardiovascular Diseases; Ubiquitin; Ligases; RNA, Untranslated; MicroRNAs; Proteasome Endopeptidase Complex
PubMed: 38515760
DOI: 10.3389/fimmu.2024.1335519