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Type I interferons (IFN), which activate many IFN-stimulated genes (ISG), are known to regulate tumorigenesis. However, little is known regarding how various ISGs coordinate with one another in developing antitumor effects. Here, we report that the ISG UBA7 is a tumor suppressor in breast cancer. UBA7 encodes an enzyme that catalyzes the covalent conjugation of the ubiquitin-like protein product of another ISG (ISG15) to cellular proteins in a process known as "ISGylation." ISGylation of other ISGs, including STAT1 and STAT2, synergistically facilitates production of chemokine-receptor ligands to attract cytotoxic T cells. These gene-activation events are further linked to clustering and nuclear relocalization of STAT1/2 within IFN-induced promyelocytic leukemia (PML) bodies. Importantly, this coordinated ISG-ISGylation network plays a central role in suppressing murine breast cancer growth and metastasis, which parallels improved survival in patients with breast cancer. These findings reveal a cooperative IFN-inducible gene network in orchestrating a tumor-suppressive microenvironment. SIGNIFICANCE: We report a highly cooperative ISG network, in which UBA7-mediated ISGylation facilitates clustering of transcription factors and activates an antitumor gene-expression program. These findings provide mechanistic insights into immune evasion in breast cancer associated with UBA7 loss, emphasizing the importance of a functional ISG-ISGylation network in tumor suppression.This article is highlighted in the In This Issue feature, p. 327.

BackgroundFlavokawain B (FKB) has been identified from kava root extracts as a potent apoptosis inducer for inhibiting the growth of various cancer cell lines, including prostate cancer. However, the molecular targets of FKB in prostate cancer cells remain unknown.MethodsAn in vitro NEDD8 Initiation Conjugation Assay was used to evaluate the neddylation inhibitory activity of FKB. Molecular docking and a cellular thermal shift assay were performed to assess the direct interaction between FKB and the NEDD8 activating enzyme (NAE) complex. Protein neddylation, ubiqutination, stability and expression in cells were assessed with immunoprecipitation and Western blotting methods using specific antibodies. Deletion and site specific mutants and siRNAs were used to evaluate deep mechanisms by which FKB induces Skp2 degradation. Cell growth inhibition and apoptosis induction were measured by MTT, ELISA and Western blotting methods.ResultsFKB inhibits NEDD8 conjugations to both Cullin1 and Ubc12 in prostate cancer cell lines and Ubc12 neddylation in an in vitro assay. Molecular docking study and a cellular thermal shift assay reveal that FKB interacts with the regulatory subunit (i.e. APP-BP1) of the NAE. In addition, FKB causes Skp2 degradation in an ubiquitin and proteasome dependent manner. Overexpression of dominant-negative cullin1 (1-452), K720R mutant (the neddylation site) Cullin1 or the F-box deleted Skp2 that losses its binding to the Skp1/Cullin1 complex causes the resistance to FKB-induced Skp2 degradation, whereas siRNA knock-down of Cdh1, a known E3 ligase of Skp2 for targeted degradation, didn't attenuate the effect of FKB on Skp2 degradation. These results suggest that degradation of Skp2 by FKB is involved in a functional Cullin1. Furthermore, proteasome inhibitors Bortezomib and MG132 transcriptionally down-regulate the expression of Skp2, and their combinations with FKB result in enhanced inhibitory effects on the growth of prostate cancer cell lines via synergistic down-regulation of Skp2 and up-regulation of p27/Kip1 and p21/WAF1 protein expression. FKB also selectively inhibits the growth of RB deficient cells with high expression of Skp2.ConclusionThese findings provide a rationale for further investigating combination of FKB and Bortezomib for treatment of RB deficient, castration-resistant prostate cancer.

Protein-protein interactions between E3 ubiquitin ligases and protein termini help shape the proteome. These interactions are sensitive to proteolysis, which alters the ensemble of cellular N and C termini. Here we describe a mechanism wherein caspase activity reveals latent C termini that are then recognized by the E3 ubiquitin ligase CHIP. Using expanded knowledge of CHIP's binding specificity, we predicted hundreds of putative interactions arising from caspase activity. Subsequent validation experiments confirmed that CHIP binds the latent C termini at tauD421 and caspase-6D179. CHIP binding to tauD421, but not tauFL, promoted its ubiquitination, while binding to caspase-6D179 mediated ubiquitin-independent inhibition. Given that caspase activity generates tauD421 in Alzheimer's disease (AD), these results suggested a concise model for CHIP regulation of tau homeostasis. Indeed, we find that loss of CHIP expression in AD coincides with the accumulation of tauD421 and caspase-6D179. These results illustrate an unanticipated link between caspases and protein homeostasis.

Stress granule (SG) formation is frequently accompanied by ubiquitin proteasome system (UPS) impairment and ubiquitylated protein accumulation. SGs, ubiquitin, and UPS components co-localize, but the relationship between the ubiquitin pathway and SGs has not been systematically characterized. We utilize pharmacological inhibition of either the ubiquitin- or NEDD8-activating enzyme (UAE or NAE) to probe whether active ubiquitylation or neddylation modulate SG dynamics. We show that UAE inhibition results in rapid loss of global protein ubiquitylation using ubiquitin-specific proteomics. Critically, inhibiting neither UAE nor NAE significantly affected SG formation or disassembly, indicating that active protein ubiquitylation or neddylation is dispensable for SG dynamics. Using antibodies with varying preference for free ubiquitin or polyubiquitin and fluorescently tagged ubiquitin variants in combination with UAE inhibition, we show that SGs co-localize primarily with unconjugated ubiquitin rather than polyubiquitylated proteins. These findings clarify the role of ubiquitin in SG biology and suggest that free ubiquitin may alter SG protein interactions.

Cycles of Cdc53/Cullin1 rubylation (a.k.a NEDDylation) protect ubiquitin-E3 SCF (Skp1-Cullin1-F-box protein) complexes from self-destruction and play an important role in mediating the ubiquitination of key protein substrates involved in cell cycle progression, development, and survival. Cul1 rubylation is balanced by the COP9 signalosome (CSN), a multi-subunit derubylase that shows 1:1 paralogy to the 26S proteasome lid. The turnover of SCF substrates and their relevance to various diseases is well studied, yet, the extent by which environmental perturbations influence Cul1 rubylation/derubylation cycles per se is still unclear. In this study, we show that the level of cellular oxidation serves as a molecular switch, determining Cullin1 rubylation/derubylation ratio. We describe a mutant of the proteasome lid subunit, Rpn11 that exhibits accumulated levels of Cullin1-Rub1 conjugates, a characteristic phenotype of csn mutants. By dissecting between distinct phenotypes of rpn11 mutants, proteasome and mitochondria dysfunction, we were able to recognize the high reactive oxygen species (ROS) production during the transition of cells into mitochondrial respiration, as a checkpoint of Cullin1 rubylation in a reversible manner. Thus, the study adds the rubylation cascade to the list of cellular pathways regulated by redox homeostasis.

Despite the similar enzyme cascade in the Ubiquitin and Ubiquitin-like peptide(Ubl) conjugation, the involvement of single or heterodimer E1 activating enzyme has been a mystery. Here, by using a quantitative Förster Resonance Energy Transfer (FRET) technology, aided with Analysis of Electrostatic Similarities Of Proteins (AESOP) computational framework, we elucidate in detail the functional properties of each subunit of the E1 heterodimer activating-enzyme for NEDD8, UBA3 and APPBP1. In contrast to SUMO activation, which requires both subunits of its E1 heterodimer AOS1-Uba2 for its activation, NEDD8 activation requires only one of two E1 subunits, UBA3. The other subunit, APPBP1, only contributes by accelerating the activation reaction rate. This discovery implies that APPBP1 functions mainly as a scaffold protein to enhance molecular interactions and facilitate catalytic reaction. These findings for the first time reveal critical new mechanisms and a potential evolutionary pathway for Ubl activations. Furthermore, this quantitative FRET approach can be used for other general biochemical pathway analysis in a dynamic mode.

The ongoing obesity epidemic has raised awareness of the complex physiology of adipose tissue. Abnormal adipocyte differentiation results in the development of systemic metabolic disorders such as insulin resistance and diabetes. The conjugation of NEDD8 (neural precursor cell expressed, developmentally downregulated 8) to target protein, termed neddylation, has been shown to mediate adipogenesis. However, much remains unknown about its role in adipogenesis. Here, we demonstrated that neddylation and its targets, the cullin (CUL) family members, are differentially regulated during mouse and human adipogenesis. Inhibition of neddylation by MLN4924 significantly reduced adipogenesis of 3T3-L1 and human stromal vascular cells. Deletion of NAE1, a subunit of the only NEDD8 E1 enzyme, suppressed neddylation and impaired adipogenesis. Neddylation deficiency did not affect mitotic cell expansion. Instead, it disrupted CREB/CEBPβ/PPARγ signaling, essential for adipogenesis. Interestingly, among the neddylation-targeted CUL family members, deletion of CUL3, but not CUL1, CUL2, or CUL4A, largely replicated the adipogenic defects observed with neddylation deficiency. A PPARγ agonist minimally rescued the adipogenic defects caused by the deletion of NAE1 and CUL3. In conclusion, our study demonstrates that neddylation and its targeted CUL3 are crucial for adipogenesis. These findings provide potential targets for therapeutic intervention in obesity and metabolic disorders.

VEXAS syndrome is a recently described entity characterized by systemic inflammatory and hematologic manifestations. The disease was first characterized by Beck et al. in 2020 in a study characterizing 25 patients with undiagnosed adult-onset inflammatory syndromes. While the literature regarding VEXAS syndrome has grown exponentially since 2020, there is still much to be understood. This lack of information leads to challenges in both the diagnosis and treatment of patients with VEXAS syndrome. Patients will often have a variety of clinical symptoms that can lead to missed or delayed diagnoses. Additionally, awareness of VEXAS syndrome is still developing among clinicians. In this comprehensive review, we summarize the current literature regarding VEXAS syndrome, and explore clinical updates of this emerging disease state. Our aim of this review is to increase awareness regarding this new disease state and identify research areas to better understand future treatment approaches for patients with VEXAS syndrome.

Spinal muscular atrophy (SMA) is one of the most frequent causes of death in childhood. The disease's molecular basis is deletion or mutations in the SMN1 gene, which produces reduced survival motor neuron protein (SMN) levels. As a result, there is spinal motor neuron degeneration and a large increase in muscle atrophy, in which the ubiquitin-proteasome system (UPS) plays a significant role. In humans, a paralogue of SMN1 , SMN2 encodes the truncated protein SMNΔ7. Structural differences between SMN and SMNΔ7 affect the interaction of the proteins with UPS and decrease the stability of the truncated protein. SMN loss affects the general ubiquitination process by lowering the levels of UBA1, one of the main enzymes in the ubiquitination process. We discuss how SMN loss affects both SMN stability and the general ubiquitination process, and how the proteins involved in ubiquitination could be used as future targets for SMA treatment.

Importance: VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome is a newly defined genetic disease with an estimated prevalence of 1 in 4269 men older than 50 years and is marked by systemic inflammation, progressive bone marrow failure, and inflammatory cutaneous manifestations., Objective: To define the spectrum of cutaneous manifestations in VEXAS syndrome and the association of these findings with clinical, genetic, and histological features., Design, Setting, and Participants: This observational cohort study included data from 112 patients who were diagnosed with VEXAS-defining genetic variants in UBA1 between 2019 and 2023. Data were collected from medical record review or from patients with VEXAS directly evaluated at the National Institutes of Health in Bethesda, Maryland., Main Outcomes and Measures: To define the spectrum of cutaneous manifestations in VEXAS in association with genetic, histological, and other clinical findings. A secondary outcome was cutaneous response to treatment in VEXAS., Results: Among the 112 patients (median [range] age, 69 [39-79] years; 111 [99%] male), skin involvement was common (93 [83%]), and the most frequent presenting feature of disease (68 [61%]). Of 64 histopathologic reports available from 60 patients, predominant skin histopathologic findings were leukocytoclastic vasculitis (23 [36%]), neutrophilic dermatosis (22 [34%]), and perivascular dermatitis (19 [30%]). Distinct pathogenic genetic variants were associated with specific cutaneous manifestations. The p.Met41Leu variant was most frequently associated with neutrophilic dermal infiltrates (14 of 17 patients [82%]), often resembling histiocytoid Sweet syndrome. In contrast, the p.Met41Val variant was associated with vasculitic lesions (11 of 20 patients [55%]) with a mixed leukocytic infiltrate (17 of 20 patients [85%]). Oral prednisone improved skin manifestations in 67 of 73 patients (92%). Patients with VEXAS treated with anakinra frequently developed severe injection-site reactions (12 of 16 [75%]), including ulceration (2 of 12 [17%]) and abscess formation (1 of 12 [8%])., Conclusions and Relevance: Results of this cohort study show that skin manifestations are a common and early manifestation of VEXAS syndrome. Genetic evaluation for VEXAS should be considered in older male patients with cutaneous vasculitis, neutrophilic dermatoses, or chondritis. Awareness of VEXAS among dermatologists is critical to facilitate early diagnosis.

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is the sole treatment option for highly malignant hematologic disease; however, the major complication-graft-versus-host disease (GVHD)-still hinders its clinical application. In addition, chronic GVHD remains the major cause of long-term morbidity and mortality after allo-HSCT. Previously we showed that bortezomib, a proteasome inhibitor, can ameliorate the sclerodermatous GVHD response while maintaining graft-versus-tumor (GVT) effects. Here we report that pevonedistat (MLN4924), an inhibitor of the Nedd8-activating enzyme, which functions upstream of the proteasome in the ubiquitin-proteasome pathway, can also show similar protective effects. Recipient mice treated with pevonedistat demonstrated inhibitory effects on sclerodermatous GVHD pathogenesis. The beneficial effect of pevonedistat was observed to be temporally dependent. Whereas treatment given at the time of allo-HSCT administration or before the onset of symptoms worsened the scleroderma response, therapeutic administration starting at 20 days post-transplantation ameliorated the sclerodermatous GVHD. Flow cytometry analysis revealed differential effects on immune subsets, with inhibition of only antigen-presenting cells and not of donor T cells. Finally, pevonedistat preserved GVT effects in a sclerodermatous murine model of B cell lymphoma. Taken together, these data suggest that inhibition of neddylation with pevonedistat can serve as an alternative approach for the treatment of GVHD while maintaining GVT effects in a murine model of sclerodermatous GVHD.

Autophagy is an evolutionarily conserved catabolic mechanism that relieves cellular stress by removing/recycling damaged organelles and debris through the action of lysosomes. Compromised autophagy has been implicated in many neurodegenerative diseases, including retinal degeneration. Here we examined retinal phenotypes resulting from RPE-specific deletion of the autophagy regulatory gene Atg7 by generating Atg7(flox/flox);VMD2-rtTA-cre+ mice to determine whether autophagy is essential for RPE functions including retinoid recycling. Atg7-deficient RPE displayed abnormal morphology with increased RPE thickness, cellular debris and vacuole formation indicating that autophagy is important in maintaining RPE homeostasis. In contrast, 11-cis-retinal content, ERGs and retinal histology were normal in mice with Atg7-deficient RPE in both fasted and fed states. Because A2E accumulation in the RPE is associated with pathogenesis of both Stargardt disease and age-related macular degeneration (AMD) in humans, deletion of Abca4 was introduced into Atg7(flox/flox);VMD2-rtTA-cre+ mice to investigate the role of autophagy during A2E accumulation. Comparable A2E concentrations were detected in the eyes of 6-month-old mice with and without Atg7 from both Abca4(-/-) and Abca4(+/+) backgrounds. To identify other autophagy-related molecules involved in A2E accumulation, we performed gene expression array analysis on A2E-treated human RPE cells and found up-regulation of four autophagy related genes; DRAM1, NPC1, CASP3, and EIF2AK3/PERK. These observations indicate that Atg7-mediated autophagy is dispensable for retinoid recycling and A2E deposition; however, autophagy plays a role in coping with stress caused by A2E accumulation.

Type I IFNs have broad activity in tissue inflammation and malignant progression that depends on the expression of IFN-stimulated genes (ISGs). ISG15, one such ISG, can form covalent conjugates to many cellular proteins, a process termed "protein ISGylation." Although type I IFNs are involved in multiple inflammatory disorders, the role of protein ISGylation during inflammation has not been evaluated. Here we report that protein ISGylation exacerbates intestinal inflammation and colitis-associated colon cancer in mice. Mechanistically, we demonstrate that protein ISGylation negatively regulates the ubiquitin-proteasome system, leading to increased production of IFN-induced reactive oxygen species (ROS). The increased cellular ROS then enhances LPS-induced activation of p38 MAP kinase and the expression of inflammation-related cytokines in macrophages. Thus our studies reveal a regulatory role for protein ISGylation in colonic inflammation and its related malignant progression, indicating that targeting ubiquitin-activating enzyme E1 homolog has therapeutic potential in treating inflammatory diseases.

Introduction: VEXAS (Vacuoles, E1 Enzyme, X-linked, autoinflammatory, Somatic) syndrome is a recently described severe adult-onset autoinflammatory disorder mediated by X-linked gene UBA1 somatic mutations, responsible of recurrent fever, skin involvement, chondritis, macrocytic anemia and inflammatory syndrome. Neurological manifestations are rarely described, and predominantly involve peripheral nervous system (PNS) impairment., Results: We report the first central nervous system (CNS) vasculitis in VEXAS syndrome, characterized by headache, cognitive dysfunction and focal signs (cerebellar ataxia). Magnetic resonance imaging (MRI) revealed multifocal white-matter lesions corresponding to recent ischemic strokes, combined with cortical hemorrhagic lesions and gadolinium enhancement of the distal wall vessels. Treatment with methylprednisone, ruxolitinib and tocilizumab led to clinical improvement and a decrease of the inflammatory syndrome. The patient died few months after due to infectious complications., Conclusion: CNS vasculitis, occurring as a manifestation of the systemic auto-inflammatory state of VEXAS syndrome, might be a rare but severe complication. We suggest that it be added to the list of inflammatory vasculopathies. More prospective studies are needed to optimize the treatment., Competing Interests: Declaration of Competing Interest Authors do not have any conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

VEXAS (Vacuoles, E1 Enzyme, X-linked, Autoinflammatory, Somatic) syndrome is a recently described autoinflammatory syndrome, mostly affecting men older than 50 years, caused by somatic mutation in the UBA1 gene, a X-linked gene involved in the activation of ubiquitin system. Patients present a broad spectrum of inflammatory manifestations (fever, neutrophilic dermatosis, chondritis, pulmonary infiltrates, ocular inflammation, venous thrombosis) and hematological involvement (macrocytic anemia, thrombocytopenia, vacuoles in myeloid and erythroid precursor cells, dysplastic bone marrow) that are responsible for a significant morbidity and mortality. The therapeutic management is currently poorly codified but is based on two main approaches: controlling inflammatory symptoms (by using corticosteroids, JAK inhibitor or tocilizumab) or targeting the UBA1-mutated hematopoietic population (by using azacitidine or allogeneic hematopoietic stem cell transplantation). Supportive care is also important and includes red blood cell or platelet transfusions, erythropoiesis stimulating agents, thromboprophylaxis and anti-infectious prophylaxis. The aim of this review is to provide a current overview of the VEXAS syndrome, particularly focusing on its pathophysiological, diagnostic and therapeutic aspects., (Copyright © 2024. Published by Elsevier Masson SAS.)

Keywords: vacuoles; myelodysplastic syndromes; ubiquitin-activating enzymes; VEXAS syndrome; autoinflammatory disorder EN vacuoles myelodysplastic syndromes ubiquitin-activating enzymes VEXAS syndrome autoinflammatory disorder 286 289 4 10/12/21 20211015 NES 211015 VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome is a recently described adult-onset inflammatory disease,1 responsible for inflammatory and haematological disorders.2 The presence of bone marrow vacuoles appeared to be greatly significant in the diagnosis of VEXAS syndrome.1 However, myeloid and erythroid vacuolization has been described in other disorders: copper deficiency,3 acute myeloid leukaemia,4 Menkès disease5 and transcobalamin II deficiency.6 Nevertheless, these disorders are not associated with chronic inflammatory signs. Vacuoles, myelodysplastic syndromes, ubiquitin-activating enzymes, autoinflammatory disorder, VEXAS syndrome Vacuoles in neutrophil precursor cells in bone marrow analysis of a patient in the VEXAS group (A) and a patient in the MDS group (B).Table SI. [Extracted from the article]

ISG15 conjugation (ISGylation) to proteins is a multistep process involving interferon (IFN)-inducible UBE1L (E1), UbcH8 (E2), and ISG15 E3 ligases (E3s). Studies performed over the past several years have shown that ISGylation plays a pivotal role in the host antiviral response against certain viruses. Recent in vitro studies revealed that human Herc5 and mouse Herc6 are major ISG15 E3 ligases, respectively. However, the global function of Herc5/6 proteins in vivo still remains unclear. Here, we report generation and initial characterization of Herc6 knockout mice. Substantial reductions of ISGylation were observed in Herc6-deficient cells after polyinosinic-polycytidylic acid double-stranded RNA injection of mice or IFN treatment of cells. On the other hand, Herc6-deficient cells and wild-type (WT) cells had similar responses to IFN stimulation, Sendai virus (Z strain) infection, and vesicular stomatitis virus infection. These results indicate that Herc6 does not play a critical role in antiviral defense of these viral infections in mice. Interestingly, male Herc6-deficient mice showed seminal vesicle hypertrophy. No such problem was detected in WT and ISG15 activating enzyme Ube1L-deficient mice. These results suggest that in addition to promoting protein ISGylation, Herc6 has a novel and protein ISGylation-independent function in the male reproductive system.

The mammalian target of rapamycin (mTOR) pathway has multiple important physiological functions, including regulation of protein synthesis, cell growth, autophagy, and synaptic plasticity. Activation of mTOR is necessary for the many beneficial effects of brain-derived neurotrophic factor (BDNF), including dendritic translation and memory formation in the hippocampus. At present, however, the role of mTOR in BDNF's support of survival is not clear. We report that mTOR activation is necessary for BDNF-dependent survival of primary rat hippocampal neurons, as either mTOR inhibition by rapamycin or genetic manipulation of the downstream molecule p70S6K specifically blocked BDNF rescue. Surprisingly, however, BDNF did not promote neuron survival by up-regulating mTOR-dependent protein synthesis or through mTOR-dependent suppression of caspase-3 activation. Instead, activated mTOR was responsible for BDNF's suppression of autophagic flux. shRNA against the autophagic machinery Atg7 or Atg5 prolonged the survival of neurons co-treated with BDNF and rapamycin, suggesting that suppression of mTOR in BDNF-treated cells resulted in excessive autophagy. Finally, acting as a physiological analog of rapamycin, IL-1β impaired BDNF signaling by way of inhibiting mTOR activation as follows: the cytokine induced caspase-independent neuronal death and accelerated autophagic flux in BDNF-treated cells. These findings reveal a novel mechanism of BDNF neuroprotection; BDNF not only prevents apoptosis through inhibiting caspase activation but also promotes neuron survival through modulation of autophagy. This protection mechanism is vulnerable under chronic inflammation, which deregulates autophagy through impairing mTOR signaling. These results may be relevant to age-related changes observed in neurodegenerative diseases.

Exploration of the ubiquitin system in eukaryotes has shown that the chemical modification of proteins by ubiquitin, known as ubiquitylation, is an incredibly important post-translational event that is crucial to numerous cellular processes. Ubiquitylation is carried out by a series of enzymes that specifically target proteins to either change their activity or their location or earmark them for degradation. Using a wide range of genome-wide approaches, the ubiquitin system has been shown to be of particular importance in the survival and propagation of the human malaria parasites. In this review, we highlight our current understanding of the ubiquitin system in Plasmodium, and discuss its possible role in the development of drug resistant malaria strains.

The phosphoinositol-3 kinase (PI3K) pathway is highly dysregulated in squamous cell carcinoma of the head and neck (SCCHN). While inhibitors of the PI3K/AKT pathway are being developed in cancer, their efficacy does not appear to be related to the presence of mutations or amplification in pathway genes. The PI3K pathway is a major regulator of macro-autophagy, an evolutionarily conserved catabolic process that degrades cellular materials to promote cellular homeostasis and survival under stress. Employing a panel of SCCHN cell lines, we observed a significant correlation between the activity of PI3K/AKT inhibitors and their ability to induce autophagy. More specifically, resistance to these inhibitors was associated with accumulation of p62/SQSTM1, a pleotropic protein that is consumed during autophagy, while loss of autophagy was, for the first time, found to be due to silencing of an essential autophagy gene, ATG7. Moreover, modulating ATG7 and p62/SQSTM1 could regulate sensitivity to PI3K/AKT inhibitors, underscoring a mechanistic link between autophagy and drug sensitivity. Analysis of human tissues revealed progressive accumulation of p62/SQSTM1 in a significant proportion of cancer samples compared to normal tissue, suggesting that defective autophagy has relevance to SCCHN. These findings are further validated by analysis of TCGA data confirming homozygous deletion and mRNA down-regulation of ATG7 in 10.0% of SCCHN samples. Taken together, these data indicate that p62/SQSTM1 levels modulate sensitivity to PI3K/AKT inhibitors; cancers vary in their capacity to undergo autophagy through epigenetic modification and, when deficient, accumulate p62/SQSTM1; and expression of autophagy-related proteins may serve as markers for resistance to PI3K/AKT inhibitors in SCCHN.

Vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic (VEXAS) syndrome is an emerging adult-onset systemic autoinflammatory disorder affecting multiple organ systems. While lung involvement is common in this syndrome, literature regarding specific patterns is sparse. In this report, we present a case description of a patient with VEXAS syndrome who presented at the emergency department on two separate occasions with acute interstitial pneumonia (AIP) and diffuse alveolar hemorrhage (DAH). A literature review with a comparison of our observed findings to the general findings of VEXAS syndrome, AIP, and DAH is provided. This report underscores the rarity of specific pulmonary manifestations associated with VEXAS syndrome, contributing valuable insight to the limited literature available on this topic.

Runs of homozygosity (ROH) are contiguous genomic regions, homozygous across all sites which arise in an individual due to the parents transmitting identical haplotypes to their offspring. The genetic improvement program of Sahiwal cattle after decades of selection needs re-assessment of breeding strategy and population phenomena. Hence, the present study was carried out to optimize input parameters in PLINK for ROH estimates, to explore ROH islands and assessment of pedigree and genome-based inbreeding in Sahiwal cattle. The sliding window approach with parameters standardized to define ROH for the specific population under study was used for the identification of runs. The optimum maximum gap, density, window-snp and window-threshold were 250 Kb, 120 Kb/SNP, 10, 0.05 respectively and ROH patterns were also characterized. ROH islands were defined as the short homozygous genomic regions shared by a large proportion of individuals in a population, containing significantly higher occurrences of ROH than the population specific threshold level. These were identified using the -homozyg-group function of the PLINK v1.9 program. Our results indicated that the Islands of ROH harbor a few candidate genes, ACAD11, RFX4, BANP, UBA5 that are associated with major economic traits. The average F PED (Pedigree based inbreeding coefficient), F ROH (Genomic inbreeding coefficient), F HOM (Inbreeding estimated as the ratio of observed and expected homozygous genotypes), F GRM (Inbreeding estimated on genomic relationship method) and F GRM0.5 (Inbreeding estimated from the diagonal of a GRM with allele frequencies near to 0.5) were 0.009, 0.091, 0.035, -0.104 and -0.009, respectively. Our study revealed the optimum parameter setting in PLINK viz. maximal gaps between two SNPs, minimal density of SNPs in a segment (in kb/SNP) and scanning window size to identify ROH segments, which will enable ROH estimation more efficient and comparable across various SNP genotyping-based studies. The result further emphasized the significant role of genomics in unraveling population diversity, selection signatures and inbreeding in the ongoing Sahiwal breed improvement programs., (© 2023. The Author(s), under exclusive licence to Institute of Plant Genetics Polish Academy of Sciences.)

Dermatomyositis constitutes a heterogeneous group of autoimmune inflammatory conditions with a wide variety of clinical outcomes. The symptomatic heterogeneity carries skin, muscle, and joint manifestations; pulmonary and cardiac involvements; and concomitant malignancy. Any of these symptoms often appear at different combinations and time courses, thus posing difficulty in early diagnosis and appropriate treatment choice. Recent progress in laboratory investigations explored the identification of several myositis-specific autoantibodies (MSAs) and myositis-associated autoantibodies, allowing precise characterization for a clinical perspective of the disease. MSAs can be detectable in approximately 80% of patients with whole dermatomyositis, some of which closely reflect unique clinical features in the particular disease subset(s), including the distribution and severity of organ involvement, treatment response, and prognosis. However, only limited evidence has been available in dermatomyositis-associated panniculitis, mostly that in anti- melanoma differentiation-associated protein 5 antibody-positive disease. We present a rare case of a patients with dermatomyositis with extensive panniculitis on the trunk whose serum IgG autoantibodies reacted with both subunits of small ubiquitin-like modifier activating enzymes (SAEs), SAE1 and SAE2. The onset of panniculitis coincided with increased disease activity, including disease-related skin manifestations, fever, dysphagia, and muscle weakness in the extremities. These symptoms responded well to a high dose of systemic steroid, but even upon receiving a high-dose intravenous immunoglobulin, the panniculitic lesions and pruritic erythema flared with tapering of steroid dose, further requiring tacrolimus and mycophenolate mofetil to achieve disease remission. To our knowledge, this is the third reported case of anti-SAE autoantibody-positive dermatomyositis with panniculitis. We aim to extend the understanding of the current limitation and further perspective in the clinical management of the extremely rare skin manifestation associated with dermatomyositis., (© 2023 Japanese Dermatological Association.)

The epidermal growth factor receptor (EGFR) signaling pathway is frequently dysregulated in a variety of human malignancies. As a result, agents have been developed to selectively inhibit the tyrosine kinase function of EGFR (EGFR-TKI) for cancer therapy. However, the clinical efficacy of these drugs to date has been limited by both acquired and intrinsic resistance. Macroautophagy, a process of intracellular proteolysis, has been shown to be activated in response to EGFR targeted therapy. However, the specific role of the induction of autophagy remains controversial. Here we show that autophagy is induced in a dose-dependent manner by in vitro treatment of multiple cancer cell lines with EGFR-TKI. Additionally, we find that in cells highly resistant to EGFR-TKI, autophagy is not robustly activated and that co-treatment of these cells with rapamycin, a known inducer of autophagy, can partially restore sensitivity to EGFR-TKI. Finally, we demonstrate that, in resistant cell lines, EGFR-TKI sensitivity can be further inhibited by siRNA-mediated depletion of the critical autophagy protein ATG7. Thus, our data suggests that defective autophagy may be an EGFR-TKI resistance mechanism and that activation of autophagy may be a viable strategy to augment the cytotoxic effect of EGFR-TKIs.

The clinical diagnosis of dermatomyositis can be difficult and challenging. In the right clinical setting and with the use of the recently described myositis specific antibodies, an earlier diagnosis can be made and therapeutic approaches promptly started, minimizing the risk of disease progression. We herein present a case of a patient with mechanic's hands and a previously documented drug eruption to hydroxychloroquine. Although these clinical findings are not pathognomonic of dermatomyositis, in the right clinical scenario, they are precious diagnostic tools. [ABSTRACT FROM AUTHOR]

Objective: Among specific autoantibodies in DM, the anti-small ubiquitin-like modifier activating enzyme (SAE) antibody is rare. We aim to describe the clinical characteristics, cancer prevalence, and muscle pathology of anti-SAE-positive DM., Methods: Patients with a diagnosis of DM and sera positive for the anti-SAE antibody were recruited from 19 centres in this retrospective observational study. The available muscular biopsies were reviewed. We conducted a comparison with anti-SAE-negative DM and a review of the literature., Results: Of the patients in the study (n = 49), 84% were women. Skin involvement was typical in 96% of patients, with 10% having calcinosis, 18% ulceration and 12% necrosis; 35% presented with a widespread skin rash. Muscular disease affected 84% of patients, with mild weakness [Medical Research Council (MRC) scale 4 (3, 5)], although 39% of patients had dysphagia. Muscular biopsies showed typical DM lesions. Interstitial lung disease was found in 21% of patients, mainly with organizing pneumonia pattern, and 26% of patients showed dyspnoea. Cancer-associated myositis was diagnosed in 16% of patients and was responsible for the majority of deaths, its prevalence being five times that of the general population. IVIG therapy was administered to 51% of the patients during the course of the disease. Comparison with anti-SAE-negative DM (n = 85) showed less and milder muscle weakness (P = 0.02 and P = 0.006, respectively), lower creatinine kinase levels (P < 0.0001) and less dyspnoea (P = 0.003)., Conclusion: Anti-SAE positive DM is a rare subgroup associated with typical skin features but a potentially diffuse rash, a mild myopathy. Interstitial lung disease defines an organizing pneumonia pattern. Cancer associated DM prevalence is five times that of the general population., Trial Registration: ClinicalTrials.gov, http://clinicaltrials.gov, NCT04637672., (© The Author(s) 2023. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

PYR-41 is an irreversible and cell permeable inhibitor of ubiquitin-activating enzyme E1, and has been reported to inhibit the degradation of IκB protein. Previous studies have shown that PYR-41 has effects on anti-inflammatory, but whether it has therapeutic effects on allergic dermatitis is unclear. The aim of this research was to explore the therapeutic effects of PYR-41 on atopic dermatitis. The effects of PYR-41 on the activation of NF-κB signaling pathway and the expression of inflammatory genes in HaCat cells were tested by western blot and qPCR. A mouse model was built, and the AD-like skin lesions were induced by 2,4-dinitrochlorobenzene (DNCB). Then, the treatment effects of PYR-41 were examined by skin severity score, ear swelling, ELISA, and qPCR. The results showed that PYR-41 can significantly reduce the K63-linked ubiquitination level of nuclear factor-κB essential modulator (NEMO) and tumor necrosis factor receptor associated factor 6 (TRAF6), inhibit the proteasomal degradation of IκBα, thereby activate TNF-α-induced NF-κB signaling pathway in HaCat cells. In addition, DNCB-treated mice have significant reduction in symptoms after treated by PYR-41, including reduced ear thickening and reduced skin damage. Serum tests showed that PYR-41 significantly reduced the expression of IgE, IFN-γ, and TNF-α. In conclusion, the current results suggest that PYR-41 has potential to reduce the symptoms of atopic dermatitis., (© 2023 Federation of American Societies for Experimental Biology.)

Background: Intrahepatic cholangiocarcinoma (ICC) is an aggressive malignancy with a poor prognosis. The underlying functions and mechanisms of circular RNA and SUMOylation in the development of ICC remain poorly understood., Methods: Circular RNA hsa&#95;circ&#95;0001681 (termed Circ-RAPGEF5 hereafter) was identified by circular RNA sequencing from 19 pairs of ICC and adjacent tissue samples. The biological function of Circ-RAPGEF5 in tumor proliferation and metastasis was examined by a series of in vitro assays. A preclinical model was used to validate the therapeutic effect of targeting Circ-RAPGEF5. RNA pull-down and dual-luciferase reporter assays were used to access the RNA interactions. Western blot and Co-IP assays were used to detect SUMOylation levels., Results: Circ-RAPGEF5, which is generated from exons 2 to 6 of the host gene RAPGEF5, was upregulated in ICC. In vitro and in vivo assays showed that Circ-RAPGEF5 promoted ICC tumor proliferation and metastasis, and inhibited apoptosis. Additionally, high Circ-RAPGEF5 expression was significantly correlated with a poor prognosis. Further investigation showed that SAE1, a potential target of Circ-RAPGEF5, was also associated with poor oncological outcomes. RNA pull-down and dual-luciferase reporter assays showed an interaction of miR-3185 with Circ-RAPGEF5 and SAE1. Co-IP and western blot assays showed that Circ-RAPGEF5 is capable of regulating SUMOylation., Conclusion: Circ-RAPGEF5 promotes ICC tumor progression and SUMOylation by acting as a sponge for miR-3185 to stabilize SAE1. Targeting Circ-RAPGEF5 or SAE1 might be a novel diagnostic and therapeutic strategy in ICC., (© 2023. Italian National Cancer Institute ‘Regina Elena’.)