PSMB8 Research Articles

DNA Methylation Profiles of PSMA6, PSMB5, KEAP1, and HIF1A Genes in Patients with Type 1 Diabetes and Diabetic Retinopathy.

We explored differences in the DNA methylation statuses of PSMA6, PSMB5, HIF1A, and KEAP1 gene promoter regions in patients with type 1 diabetes and different diabetic retinopathy (DR) stages. Study subjects included individuals with no DR (NDR, n = 41), those with non-proliferative DR (NPDR, n = 27), and individuals with proliferative DR or those who underwent laser photocoagulation (PDR/LPC, n = 46). DNA methylation was determined by Zymo OneStep qMethyl technique. The methylation of PSMA6 (NDR 5.9 (3.9-8.7) %, NPDR 4.5 (3.8-5.7) %, PDR/LPC 6.6 (4.7-10.7) %, p = 0.003) and PSMB5 (NDR 2.2 (1.9-3.7) %, NPDR 2.2 (1.9-3.0) %, PDR/LPC 3.2 (2.5-7.1) %, p < 0.01) differed across the groups. Consistent correlations were observed between the methylation levels of HIF1A and PSMA6 in all study groups. DNA methylation levels of PSMA6, PSMB5, and HIF1A genes were positively correlated with the duration of diabetes, HbA1c, and albuminuria in certain study groups. Univariate regression models revealed a significant association between the methylation level z-scores of PSMA6, PSMB5, and HIF1A and severe DR (PSMA6: OR = 1.96 (1.15; 3.33), p = 0.013; PSMB5: OR = 1.90 (1.14; 3.16), p = 0.013; HIF1A: OR = 3.19 (1.26; 8.06), p = 0.014). PSMB5 remained significantly associated with DR in multivariate analysis. Our findings suggest significant associations between the severity of DR and the DNA methylation levels of the genes PSMA6, PSMB5, and HIF1A, but not KEAP1 gene.

A novel PSMB8 isoform associated with multiple sclerosis lesions induces P-body formation.

Multiple sclerosis (MS) is an inflammatory and demyelinating disease of the central nervous system (CNS). Current therapies primarily target the inflammatory component of the disease and are highly effective in early stages of MS while limited therapies have an effect in the more chronic progressive stages of MS where resident glia have a larger role. MS lesions tend to be inflammatory even after the initial peripheral immune cell invasion has subsided and this inflammation is known to cause alternative splicing events. We used qPCR of normal-appearing white matter and white matter lesions from postmortem MS tissue, in vitro studies, and immunostaining in MS tissue to investigate the alternative splicing of one gene known to be important during recovery in an animal model of MS, PSMB8. We found a novel, intron-retained isoform which has not been annotated, upregulated specifically in MS patient white matter lesions. We found that this novel isoform activates the nonsense-mediated decay pathway in primary human astrocytes, the most populous glial cell in the CNS, and is then degraded. Overexpression of this isoform in astrocytes leads to an increased number of processing bodies in vitro, the primary site of mRNA decay. Finally, we demonstrated that MS white matter lesions have a higher burden of processing bodies compared to normal-appearing white matter, predominantly in GFAP-positive astrocytes. The increase in alternative splicing of the PSMB8 gene, the stress that this alternative splicing causes, and the observation that processing bodies are increased in white matter lesions suggests that the lesion microenvironment may lead to increased alternative splicing of many genes. This alternative splicing may blunt the protective or reparative responses of resident glia in and around white matter lesions in MS patients.

Generation of murine tumor models refractory to αPD-1/-L1 therapies due to defects in antigen processing/presentation or IFNγ signaling using CRISPR/Cas9.

Immune checkpoint blockade (ICB) targeting the programmed cell death protein 1 (PD-1) and its ligand 1 (PD-L1) fails to provide clinical benefit for most cancer patients due to primary or acquired resistance. Drivers of ICB resistance include tumor antigen processing/presentation machinery (APM) and IFNγ signaling mutations. Thus, there is an unmet clinical need to develop alternative therapies for these patients. To this end, we have developed a CRISPR/Cas9 approach to generate murine tumor models refractory to PD-1/-L1 inhibition due to APM/IFNγ signaling mutations. Guide RNAs were employed to delete B2m, Jak1, or Psmb9 genes in ICB-responsive EMT6 murine tumor cells. B2m was deleted in ICB-responsive MC38 murine colon cancer cells. We report a detailed development and validation workflow including whole exome and Sanger sequencing, western blotting, and flow cytometry to assess target gene deletion. Tumor response to ICB and immune effects of gene deletion were assessed in syngeneic mice. This workflow can help accelerate the discovery and development of alternative therapies and a deeper understanding of the immune consequences of tumor mutations, with potential clinical implications.

Effects of tea catechin extracts from BB35 and purple (TRFK 306) tea clones on the gene expression of Egfr, App, Bcl2, Dnmt, Casp3, Hif1a, Gadd45b and Psmb5 genes involved in triple negative breast cancer diseases: In silico and in vitro study

Tea has been shown to contain metabolites that exhibit antioxidant, anti-inflammatory, anti-diabetic, anti-cancer and anti-cardio vascular diseases properties. This study aimed to carry out an in silico assessment of catechins on the genes previously shown to be involved in Triple Negative Breast Cancer (TNBC) disease and also to evaluate the effects of catechin extracts from purple (TRFK306) and BB35 tea clones on the expression patterns of genes in the 4T1 TNBC cell line as mentioned above. Identification and quantification of different catechin contents in these two tea clones were performed by using High-Performance Liquid Chromatography (HPLC). In silico assessment including Absorption, Distribution, Metabolism and Excretion (ADME) study for drug-likeness evaluation, Drug target prediction, Protein-protein interaction (PPI) network analysis and construction, Gene Ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) enrichment and analysis for targets and Molecular docking study was conducted. Simplified Molecular Input Line Entry System (SMILES) of 4 different tea catechins showed a target on 111 genes in TNBC and have high binding affinity to the receptor-binding pocket of chain A of Epidermal Growth Factor Receptor (EGFR) Extracellular Domains. Catechin extracts promoted the downregulation of expression of 6 genes (Egfr, App, Bcl2, Dnmt, Hif1a and Psmb5) and the upregulation of 2 genes (Casp3 and Gadd45b) in the 4T1 TNBC cell line. Catechin extracts from purple tea clones showed higher activity on gene expression levels of Egfr, Bcl2 and Casp3 than catechin extracts from BB35 tea clone.

Dynamic Changes in the Activities and Contents of Particular Proteasome Forms in the Cerebral Cortex of C57BL/6 Mice during Aging

—Proteasomes are key components of the ubiquitin–proteasome system. Various forms of proteasomes are known. During aging, disturbances in the functioning of proteasomes have been revealed, as well as increased expression of their particular forms. Considering these data, we studied the expression of genes encoding the constitutive and immune subunits of proteasomes in cerebral cortex samples from C57BL/6 mice at the ages of 60, 190, 380, and 720 days. In addition, the contents of constitutive and immune proteasome subunits, chymotrypsin-like and caspase-like activities of proteasome pools, as well as the activity of the β5i immune subunit were studied in tissue homogenates. The chymotrypsin-like activity and the activity of the β5i subunit of different forms of proteasomes separated by electrophoresis in native gel were characterized. Compared with samples from young animals, in the cerebral cortex of animals at an age of 720 days the following changes in the expression patterns of proteasome genes were revealed: a decreased expression of the PSMB5 gene encoding constitutive proteasome subunit β5; increased expression of genes encoding immune proteasome subunits β5i and β1i. In tissue homogenates of aged mice, an increase in the content of immune subunits β1i and β2i was shown. In samples from old animals, chymotrypsin-like activity was decreased and a tendency to a decrease in caspase-like activity of proteasomes as well as the β5i subunit activity was revealed. Analysis of the activity of native complexes in tissues obtained from old animals revealed decreased chymotrypsin-like activity of 26S and 20S proteasomes containing the β5i subunit. Based on the obtained data, it can be assumed that changes in the pool of nonconstitutive proteasomes reflect aging-associated adaptive processes in the mouse brain.

The Genetic Diversity of Proteasome Genes in the T1DM Polish Population.

In the present study, the genetic variations in PSMB5 (rs11543947), PSMA6 (rs2277460, rs1048990), PSMC6 (rs2295826, rs2295827) and PSMA3 (rs2348071) UPS gene cluster was investigated in type 1 diabetes and healthy donors in the Polish population. The study comprised 105 patients with type 1 diabetes mellitus (T1DM) and 214 controls. All were genotyped by PCR and restriction digestion analysis or Sanger sequencing. Rs1048990 and rs2348071 were found to be neutral to T1DM (p-value: 0.499 and 0.656, respectively). According to the multiple loci genotype (MLG) analysis, the major homozygote of the tested polymorphisms had a protective effect. The most common MLG in the T1DM group was characterised by simultaneous risk factors at rs11543947, rs2277460, rs2295826 and rs2295827 (pvalue: <0.0001 vs. MGL1). Multiple locus haplotype analysis revealed a similar dependence, with common alleles at all tested loci demonstrating a protective effect, and the rare alleles increasing T1DM risk (p-value: <0.0001 vs. MLH1). Our study suggests that the proteasome gene polymorphisms rs11543947, rs2277460, rs2295826, and rs2295827 could be potential markers for T1DM susceptibility in the Polish population.

Dynamic Changes in the Activity and Content of Particular Proteasome Forms in Cerebral Cortex of C57BL/6 Mice during Aging

Proteasomes are key components of the ubiquitin-proteasome system. Various forms of proteasomes are known. During aging, disturbances in the functioning of proteasomes were revealed, as well as an increased expression of their individual forms. Considering these data, we studied the expression of genes encoding the constitutive and immune subunits of proteasomes in the cerebral cortex samples from C57BL/6 mice at the age of 60, 190, 380, and 720 days. In addition, the content of constitutive and immune proteasome subunits, chymotrypsin-like and caspase-like activities of proteasome pools, as well as the activity of the β5i immune subunit were studied in tissue homogenates. The chymotrypsin-like activity and the activity of the β5i subunit of different forms of proteasomes separated by electrophoresis under native conditions were characterized. Compared with samples from young animals, in the cerebral cortex of animals aged 720 days the following changes in the expression patterns of proteasome genes were revealed: a decrease in the expression of PSMB5 gene encoding the constitutive proteasome subunit β5; activation of genes encoding immune subunits β5i and β1i. In clarified tissue homogenates of aged mice, an increase in the content of immune subunits β1i and β2i was shown. In samples from old animals, decreased chymotrypsin-like activity and a tendency to a decrease in caspase-like activity of proteasomes as well as the β5i subunit activity were also revealed. Analysis of the activity of native complexes in the tissues of old animals revealed decreased chymotrypsin-like activity of both 26S and 20S proteasomes containing the β5i subunit. Based on the data obtained, it can be assumed that changes in the pool of non-constitutive proteasomes reflect aging-associated adaptive processes in mouse brain.

Dynamic Changes in the Activities and Contents of Particular Proteasome Forms in the Cerebral Cortex of C57BL/6 Mice during Aging

Proteasomes are key components of the ubiquitin-proteasome system. Various forms of proteasomes are known. During aging, disturbances in the functioning of proteasomes have been revealed, as well as increased expression of their particular forms. Considering these data, we studied the expression of genes encoding the constitutive and immune subunits of proteasomes in cerebral cortex samples from C57BL/6 mice at the ages of 60, 190, 380, and 720 days. In addition, the contents of constitutive and immune proteasome subunits, chymotrypsin-like and caspase-like activities of proteasome pools, as well as the activity of the β5i immune subunit were studied in tissue homogenates. The chymotrypsin-like activity and the activity of the β5i subunit of different forms of proteasomes separated by electrophoresis in native gel were characterized. Compared with samples from young animals, in the cerebral cortex of animals at an age of 720 days the following changes in the expression patterns of proteasome genes were revealed: a decreased expression of the PSMB5 gene encoding constitutive proteasome subunit β5; increased expression of genes encoding immune proteasome subunits β5i and β1i. In tissue homogenates of aged mice, an increase in the content of immune subunits β1i and β2i was shown. In samples from old animals, chymotrypsin-like activity was decreased and a tendency to a decrease in caspase-like activity of proteasomes as well as the β5i subunit activity was revealed. Analysis of the activity of native complexes in tissues obtained from old animals revealed decreased chymotrypsin-like activity of 26S and 20S proteasomes containing the β5i subunit. Based on the obtained data, it can be assumed that changes in the pool of nonconstitutive proteasomes reflect aging-associated adaptive processes in the mouse brain.

Changes in the Activities and Contents of Individual Forms of Proteasomes in Samples of the Cerebral Cortex during Pathology Development in 5xFAD Mice

The ubiquitin-proteasome system (UPS) provides hydrolysis of most intracellular proteins in proteasomes. There are various forms of proteasomes that differ, among other things, in the set of proteolytic subunits and the presence of activators. Alzheimer's disease (AD) is characterized by disturbances in the functional state of the UPS. At the same time, an increase in the expression of certain forms of proteasomes, in particular, proteasomes containing immune subunits (nonconstitutive proteasomes), has been shown. Here, we studied dynamic changes in the expression of catalytic proteasome subunit genes and corresponding proteins in the cerebral cortex of animals using a mouse model of AD (5xFAD transgenic mice). Increases by 4 and 6 folds in transcripts of the PSMB9 and PSMB8 genes encoding immune proteasome subunits were detected, as well as a significant increase in the content of immune β-subunits (by 2.8 folds, β1i; 2.2 folds, β2i) in samples from 5xFAD mice at the age of 380 days, compared with samples from mice at 60 days of age. Moreover, the activation of both 20S and 26S proteasomes containing immune subunits were revealed in samples from 380 days old 5xFAD mice by electrophoresis in native conditions. This indicates activated synthesis of the immune subunits and assembly of nonconstitutive proteasomes at the terminal stage of pathology development. The obtained data, in combination with the available literature, indicate that the activation of nonconstitutive proteasomes is a universal phenomenon characteristic of various animal models of AD, which may reflect both the development of neuroinflammation and adaptive processes in tissues induced by the accumulation of toxic protein aggegates.

53 Nakajo-Nishimura syndrome: the first African case

Nakajo-Nishimura syndrome is a hereditary autoinflammatory disorder caused by an autosomal recessive homozygous mutation of the PSMB8 gene, which encodes the immunoproteasome subunit beta 5i. The clinical manifestations of NNS are mainly pernio-like skin rashes, nodular erythema, lipodystrophy, clubbed fingers, remittent fever, hepatosplenomegaly, and basal ganglia calcifications. Here we are reporting a case of NNS in an 11-year-old girl, who lives in eastern Algeria, born from a first-degree consanguineous marriage, she presented with erythematous patches on her face and her back, nodular erythema on her neck, swollen and painful fingers with acrocyanosis and recurrent fever that mainly occurred in cold weather. The patient received long-term treatment with low-dose glucocorticoids, along with immunomodulatory drugs (hydroxychloroquine with methotrexate), partial improvement clinically and biologically was observed. Colchicine was added to her treatment, with increased prednisone doses when she recently developed an AA amyloidosis. Our patient was diagnosed clinically with NNS because she exhibited six of the eight characteristics. To the best of our knowledge, this is the first case of NNS in Africa.

Assessment of type I interferon signatures in undifferentiated inflammatory diseases: A Japanese multicenter experience.

PurposeUpregulation of type I interferon (IFN) signaling has been increasingly detected in inflammatory diseases. Recently, upregulation of the IFN signature has been suggested as a potential biomarker of IFN-driven inflammatory diseases. Yet, it remains unclear to what extent type I IFN is involved in the pathogenesis of undifferentiated inflammatory diseases. This study aimed to quantify the type I IFN signature in clinically undiagnosed patients and assess clinical characteristics in those with a high IFN signature.MethodsThe type I IFN signature was measured in patients’ whole blood cells. Clinical and biological data were collected retrospectively, and an intensive genetic analysis was performed in undiagnosed patients with a high IFN signature.ResultsA total of 117 samples from 94 patients with inflammatory diseases, including 37 undiagnosed cases, were analyzed. Increased IFN signaling was observed in 19 undiagnosed patients, with 10 exhibiting clinical features commonly found in type I interferonopathies. Skin manifestations, observed in eight patients, were macroscopically and histologically similar to those found in proteasome-associated autoinflammatory syndrome. Genetic analysis identified novel mutations in the PSMB8 gene of one patient, and rare variants of unknown significance in genes linked to type I IFN signaling in four patients. A JAK inhibitor effectively treated the patient with the PSMB8 mutations. Patients with clinically quiescent idiopathic pulmonary hemosiderosis and A20 haploinsufficiency showed enhanced IFN signaling.ConclusionsHalf of the patients examined in this study, with undifferentiated inflammatory diseases, clinically quiescent A20 haploinsufficiency, or idiopathic pulmonary hemosiderosis, had an elevated type I IFN signature.

Pan-cancer analysis of genomic and transcriptomic data reveals the prognostic relevance of human proteasome genes in different cancer types

BackgroundThe human proteasome gene family (PSM) consists of 49 genes that play a crucial role in cancer proteostasis. However, little is known about the effect of PSM gene expression and genetic alterations on clinical outcome in different cancer forms.MethodsHere, we performed a comprehensive pan-cancer analysis of genetic alterations in PSM genes and the subsequent prognostic value of PSM expression using data from The Cancer Genome Atlas (TCGA) containing over 10,000 samples representing up to 33 different cancer types. External validation was performed using a breast cancer cohort and KM plotter with four cancer types.ResultsThe PSM genetic alteration frequency was high in certain cancer types (e.g. 67%; esophageal adenocarcinoma), with DNA amplification being most common. Compared with normal tissue, most PSM genes were predominantly overexpressed in cancer. Survival analysis also established a relationship with PSM gene expression and adverse clinical outcome, where PSMA1 and PSMD11 expression were linked to more unfavorable prognosis in ≥ 30% of cancer types for both overall survival (OS) and relapse-free interval (PFI). Interestingly, PSMB5 gene expression was associated with OS (36%) and PFI (27%), and OS for PSMD2 (42%), especially when overexpressed. ConclusionThese findings indicate that several PSM genes may potentially be prognostic biomarkers and novel therapeutic targets for different cancer forms.

Proteasome dysfunction disrupts adipogenesis and induces inflammation via ATF3

ObjectiveRegulation of proteasomal activity is an essential component of cellular proteostasis and function. This is evident in patients with mutations in proteasome subunits and associated regulators, who suffer from proteasome-associated autoinflammatory syndromes (PRAAS). These patients display lipodystrophy and fevers, which may be partly related to adipocyte malfunction and abnormal thermogenesis in adipose tissue. However, the cell–intrinsic pathways that could underlie these symptoms are unclear. Here, we investigate the impact of two proteasome subunits implicated in PRAAS, Psmb4 and Psmb8, on differentiation, function and proteostasis of brown adipocytes. MethodsIn immortalized mouse brown pre-adipocytes, levels of Psmb4, Psmb8, and downstream effectors genes were downregulated through reverse transfection with siRNA. Adipocytes were differentiated and analyzed with various assays of adipogenesis, lipogenesis, lipolysis, inflammation, and respiration. ResultsLoss of Psmb4, but not Psmb8, disrupted proteostasis and adipogenesis. Proteasome function was reduced upon Psmb4 loss, but partly recovered by the activation of Nuclear factor, erythroid-2, like-1 (Nfe2l1). In addition, cells displayed higher levels of surrogate inflammation and stress markers, including Activating transcription factor-3 (Atf3). Simultaneous silencing of Psmb4 and Atf3 lowered inflammation and restored adipogenesis. ConclusionsOur study shows that Psmb4 is required for adipocyte development and function in cultured adipocytes. These results imply that in humans with PSMB4 mutations, PRAAS-associated lipodystrophy is partly caused by disturbed adipogenesis. While we uncover a role for Nfe2l1 in the maintenance of proteostasis under these conditions, Atf3 is a key effector of inflammation and blocking adipogenesis. In conclusion, our work highlights how proteasome dysfunction is sensed and mitigated by the integrated stress response in adipocytes with potential relevance for PRAAS patients and beyond.

Human induced pluripotent stem cells generated from Chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperature (CANDLE) syndrome patients with a homozygous mutation in the PSMB8 gene (NIHTVBi016-A, NIHTVBi017-A, NIHTVBi018-A)

We have successfully generated induced pluripotent stem cells (iPSC) from dermal fibroblasts and peripheral blood mononuclear cells from patients with a homozygous missense mutation in the gene encoding PSMB8. Biallelic loss of function mutations in this gene are responsible for the PSMB8 deficiency termed Chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperature (CANDLE). The iPSC carrying the homozygous PSMB8 gene mutation (c.224C > T, T75M) are phenotypically normal and have the capacity to differentiate toward the three germ layers. These iPSC have great potential to study the role of PMSB8 in the regulation of immune responses and other cellular pathways.

UM171A-induced ROS promote antigen cross-presentation of immunogenic peptides by bone marrow-derived mesenchymal stromal cells

BackgroundMesenchymal stromal cells (MSCs) have been extensively used in the clinic due to their exquisite tissue repair capacity. However, they also hold promise in the field of cellular vaccination as they can behave as conditional antigen presenting cells in response to interferon (IFN)-gamma treatment under a specific treatment regimen. This suggests that the immune function of MSCs can be pharmacologically modulated. Given the capacity of the agonist pyrimido-indole derivative UM171a to trigger the expression of various antigen presentation-related genes in human hematopoietic progenitor cells, we explored the potential use of UM171a as a means to pharmacologically instill and/or promote antigen presentation by MSCs.MethodsBesides completing a series of flow-cytometry-based phenotypic analyses, several functional antigen presentation assays were conducted using the SIINFEKL-specific T-cell clone B3Z. Anti-oxidants and electron transport chain inhibitors were also used to decipher UM171a’s mode of action in MSCs. Finally, the potency of UM171a-treated MSCs was evaluated in the context of therapeutic vaccination using immunocompetent C57BL/6 mice with pre-established syngeneic EG.7T-cell lymphoma.ResultsTreatment of MSCs with UM171a triggered potent increase in H2-Kb cell surface levels along with the acquisition of antigen cross-presentation abilities. Mechanistically, such effects occurred in response to UM171a-mediated production of mitochondrial-derived reactive oxygen species as their neutralization using anti-oxidants or Antimycin-A mitigated MSCs’ ability to cross-present antigens. Processing and presentation of the immunogenic ovalbumin-derived SIINFEKL peptide was caused by de novo expression of the Psmb8 gene in response to UM171a-triggered oxidative stress. When evaluated for their anti-tumoral properties in the context of therapeutic vaccination, UM171a-treated MSC administration to immunocompetent mice with pre-established T-cell lymphoma controlled tumor growth resulting in 40% survival without the need of additional supportive therapy and/or standard-of-care.ConclusionsAltogether, our findings reveal a new immune-related function for UM171a and clearly allude to a direct link between UM171a-mediated ROS induction and antigen cross-presentation by MSCs. The fact that UM171a treatment modulates MSCs to become antigen-presenting cells without the use of IFN-gamma opens-up a new line of investigation to search for additional agents capable of converting immune-suppressive MSCs to a cellular tool easily adaptable to vaccination.Graphical abstract

CANDLE Syndrome: Case Report of a Rare Type of Auto- Inflammatory Disease

CANDLE syndrome (chronic atypical neutophilic dermatosis with lipodystrophy and elevated temperature) is an autoinflammatory disease/syndrome characterized by recurrent fever, skin lesions, and multisystem inflammatory manifestations. Most of the patients have shown mutation in PSMB8 gene. Here, we report a 9-year-old girl with recurrent fever, atypical facies, widespread skin lesions, generalized lymphadenopathy, hepato-splenomegaly, lipodystrophy, and failure to thrive. Considering the clinical features and laboratory investigations including skin biopsy findings, diagnosis was consistent with CANDLE syndrome. Therefore, it is recommended to consider CANDLE syndrome in a young child who presents with recurrent fever, characteristics rashes, organomegaly and failure to thrive.&#x0D; Bangladesh J Child Health 2020; VOL 44 (3) :174-177

Pluripotent stem cell-based screening identifies CUDC-907 as an effective compound for restoring the in vitro phenotype of Nakajo-Nishimura syndrome.

Nakajo‐Nishimura syndrome (NNS) is an autoinflammatory disorder caused by a homozygous mutations in the PSMB8 gene. The administration of systemic corticosteroids is partially effective, but continuous treatment causes severe side effects. We previously established a pluripotent stem cell (PSC)‐derived NNS disease model that reproduces several inflammatory phenotypes, including the overproduction of monocyte chemoattractant protein‐1 (MCP‐1) and interferon gamma‐induced protein‐10 (IP‐10). Here we performed high‐throughput compound screening (HTS) using this PSC‐derived NNS model to find potential therapeutic candidates and identified CUDC‐907 as an effective inhibitor of the release of MCP‐1 and IP‐10. Short‐term treatment of CUDC‐907 did not induce cell death within therapeutic concentrations and was also effective on primary patient cells. Further analysis indicated that the inhibitory effect was post‐transcriptional. These findings suggest that HTS with PSC‐derived disease models is useful for finding drug candidates for autoinflammatory diseases.

Genetic polymorphisms of proteasome subunit genes of the MHC-I antigen-presenting system are associated with cervical cancer in a Chinese Han population

Proteasome subunit beta types 8 and 9 (PSMB8, PSMB9) play critical roles in the human leukocyte antigen class I (HLA I)-presenting system. Studies have suggested that polymorphisms in the PSMB8 and PSMB9 genes may influence the immune functions of PSMB8 and PSMB9, and thus be associated with various human cancers. We investigated associations involving single nucleotide polymorphisms (SNPs) rs2071543 in PSMB8, rs1351383, rs17587 and rs2127675 in PSMB9 and risk of cervical intraepithelial neoplasia (CIN) and cervical cancer in a Chinese Han population. A total of 543 patients with CIN, 1008 patients with cervical cancer, and 1120 healthy individuals were enrolled. Agena MassArray was used for SNP genotyping of PSMB8 and PSMB9. Associations involving these SNPs and risk of CIN and cervical cancer were analysed. Our results showed that the PSMB8 T/T and T/G genotypes of rs2071543 may be associated with a higher risk of CIN (P = 0.011, OR = 1.35,95% CI: 1.07–1.70) and cervical cancer (P = 0.006, OR = 1.31, 95% CI: 1.08–1.59). For rs17587, the A allele (P = 0.001, OR = 1.303, 95% CI: 1.115–1.522), and the A/A and A/G genotypes (P = 0.001, OR = 1.36, 95% CI: 1.13–1.63) may be risk factors for cervical cancer. These results indicated that PSMB8 rs2071543 might influence susceptibility to CIN and cervical cancer, and PSMB9 rs17587 might influence cervical cancer susceptibility in a Chinese Han population.

A Chinese case of Nakajo\u2013Nishimura syndrome with novel compound heterozygous mutations of the PSMB8 gene

BackgroundNakajo-Nishimura syndrome (NNS) is an autosomal recessive heredity disorder, one of a spectrum of autoinflammatory diseases named proteasome-associated autoinflammatory syndrome (PRAAS) caused by mutations of PSMB8 gene. NNS is characterized by pernio-like skin rashes, intermittent fever, and long clubbed fingers and toes with joint contractures, partially with progressive lipomuscular atrophy, emaciation, hepatosplenomegaly and basal ganglion calcification.Case presentationWe presented a sporadic case of NNS with compound heterozygous mutations in the PSMB8 gene. The 4-year-old boy was affected by progressive erythematous plaques on his nose and gradually involved hands and feet later with characteristic appearance of long clubbed fingers. The repetitive periodic intermittent fever was recorded. By gene sequencing, novel compound heterozygous mutations c.373C > T (p.R125C) and c.355G > A (p.D119N) in the PSMB8 gene were found. The patient responded well to low dosage of oral methylprednisolone.ConclusionsWe reported novel compound heterozygous mutations in PSMB8 in a sporadic Chinese NNS patient.

A novel mouse model of proteasome associated autoinflammatory syndromes

Abstract Proteasome associated autoinflammatory syndromes (PRAAS) represent a rare class of early-onset autoinflammatory diseases, including chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperature (CANDLE syndrome). CANDLE is an inherited autosomal recessive disease associated with recurrent fevers, skin lesions, lipodystrophy and other comorbidities. Point mutations in the proteasome subunit beta type-8 (psmb8) gene, which encodes the beta-5i (ß5i) catalytic subunit of the 20S immunoproteasome, have been linked to CANDLE. The immunoproteasome is induced in cells in response to interferon (IFN) signaling. In cells lacking functional immunoproteasomes, oxidant-damaged proteins aggregate and likely create a feed-forward loop resulting in greater cytokine-mediated stress. We have developed a novel mouse model via targeted mutation within the psmb8 gene, which harbors a specific point mutation (224C&amp;gt;T) present in CANDLE patients. Our data shows that this mutation leads to marked differences in the expression of the immunoproteasome subunit ß5i within these mice. Thus, this mouse model is likely to exhibit changes in the immunoproteasome consistent with human disease upon interferon signaling. As mice with the targeted mutation do not directly yield a CANDLE-like phenotype at rest, it suggests that induction of disease-associated morbidity requires additional drivers. To test this, we are investigating interferons as initiators of disease pathogenesis. Future research will entail subjecting these mice to viral infection in order to identify if such triggers can initiate PRAAS-like symptoms in CANDLE patients. These mice may prove to an essential tool in understanding such disorders.