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Multiple studies have demonstrated that cancer cells with microsatellite instability (MSI) are intolerant to loss of the Werner syndrome helicase (WRN), whereas microsatellite-stable (MSS) cancer cells are not. Therefore, WRN represents a promising new synthetic lethal target for developing drugs to treat cancers with MSI. Given the uncertainty of how effective inhibitors of WRN activity will prove in clinical trials, and the likelihood of tumours developing resistance to WRN inhibitors, alternative strategies for impeding WRN function are needed. Proteolysis-targeting chimeras (PROTACs) are heterobifunctional small molecules that target specific proteins for degradation. Here, we engineered the WRN locus so that the gene product is fused to a bromodomain (Bd)-tag, enabling conditional WRN degradation with the AGB-1 PROTAC specific for the Bd-tag. Our data revealed that WRN degradation is highly toxic in MSI but not MSS cell lines. In MSI cells, WRN degradation caused G2/M arrest, chromosome breakage and ATM kinase activation. We also describe a multi-colour cell-based platform for facile testing of selective toxicity in MSI versus MSS cell lines. Together, our data show that a degrader approach is a potentially powerful way of targeting WRN in MSI cancers and paves the way for the development of WRN-specific PROTAC compounds. [ABSTRACT FROM AUTHOR]

This review starts off with the first germline homozygous variants of the Nucleoporin 98 gene (NUP98) in siblings whose clinical presentation recalls Rothmund–Thomson (RTS) and Werner (WS) syndromes. The progeroid phenotype caused by a gene associated with haematological malignancies and neurodegenerative disorders primed the search for interplay between caretakers involved in genome instability syndromes and Nuclear Pore Complex (NPC) components. In the context of basic information on NPC architecture and functions, we discuss the studies on the interdependence of caretakers and gatekeepers in WS and Hereditary Fibrosing Poikiloderma (POIKTMP), both entering in differential diagnosis with RTS. In WS, the WRN/WRNIP complex interacts with nucleoporins of the Y-complex and NDC1 altering NPC architecture. In POIKTMP, the mutated FAM111B, recruited by the Y-complex's SEC13 and NUP96, interacts with several Nups safeguarding NPC structure. The linkage of both defective caretakers to the NPC highlights the attempt to activate a repair hub at the nuclear periphery to restore the DNA damage. The two separate WS and POIKTMP syndromes are drawn close by the interaction of their damage sensors with the NPC and by the shared hallmark of short fragile telomeres disclosing a major role of both caretakers in telomere maintenance. [ABSTRACT FROM AUTHOR]

AimsWerner Syndrome is a rare premature ageing autosomal recessive disorder caused by pathogenic variants in the WRN gene. People with Werner Syndrome may develop diabetes mellitus. Chronic foot ulceration is seen, with some characteristics overlapping with diabetic foot disease. However, the clinical course of the ulceration is atypical of diabetic foot disease. We present four siblings from an Irish Traveller family with Werner Syndrome to highlight the complexity of this condition. The Irish Traveller population are an indigenous, endogamous population in which consanguinity is common. As a result, rare autosomal recessive disorders are prevalent among this population:. Methods: We describe our experience managing the complex foot disease seen in all four siblings. Foot complications present in the siblings include painful peripheral neuropathy, chronic foor ulceration, underlying osteomyelitis and acral melanoma. Results: The cases are described individually, with a particular focus on the complex foot disease associated with the condition. Conclusions: Although the siblings attend a diabetic foot clinic, we suggest that the combination of clinical features seen in these cases is unique to Werner syndrome and warrants the title 'Werner Syndrome' (rather than 'Diabetic') foot. [ABSTRACT FROM AUTHOR]

Abstract Multiple studies have demonstrated that cancer cells with microsatellite instability (MSI) are intolerant to loss of the Werner syndrome helicase (WRN), whereas microsatellite-stable (MSS) cancer cells are not. Therefore, WRN represents a promising new synthetic lethal target for developing drugs to treat cancers with MSI. Given the uncertainty of how effective inhibitors of WRN activity will prove in clinical trials, and the likelihood of tumours developing resistance to WRN inhibitors, alternative strategies for impeding WRN function are needed. Proteolysis-targeting chimeras (PROTACs) are heterobifunctional small molecules that target specific proteins for degradation. Here, we engineered the WRN locus so that the gene product is fused to a bromodomain (Bd)-tag, enabling conditional WRN degradation with the AGB-1 PROTAC specific for the Bd-tag. Our data revealed that WRN degradation is highly toxic in MSI but not MSS cell lines. In MSI cells, WRN degradation caused G2/M arrest, chromosome breakage and ATM kinase activation. We also describe a multi-colour cell-based platform for facile testing of selective toxicity in MSI versus MSS cell lines. Together, our data show that a degrader approach is a potentially powerful way of targeting WRN in MSI cancers and paves the way for the development of WRN-specific PROTAC compounds.

Werner syndrome (WS) is an autosomal recessive disease caused by loss of function of WRN. WS is a segmental progeroid disease and shows early onset or increased frequency of many characteristics of normal aging. WRN possesses helicase, annealing, strand exchange, and exonuclease activities and acts on a variety of DNA substrates, even complex replication and recombination intermediates. Here, we review the genetics, biochemistry, and probably physiological functions of the WRN protein. Although its precise role is unclear, evidence suggests WRN plays a role in pathways that respond to replication stress and maintain genome stability particularly in telomeric regions. [ABSTRACT FROM AUTHOR]

James German's work to establish the natural history and cancer risk associated with Bloom syndrome (BS) has had a strong influence on the generation of scientists and clinicians working to understand other RECQ deficiencies and heritable cancer predisposition syndromes. I summarize work by us and others below, inspired by James German's precedents with BS, to understand and compare BS with the other heritable RECQ deficiency syndromes with a focus on Werner syndrome (WS). What we know, unanswered questions and new opportunities are discussed, as are potential ways to treat or modify WS-associated disease mechanisms and pathways. [ABSTRACT FROM AUTHOR]

Systemic sclerosis (SSc) is a rare disease which belongs to the group of systemic connective tissue diseases characterised by thickening and fibrosis of the skin and internal organs with their failure. Diseases with similar clinical manifestations are referred to as the so-called scleroderma-like syndromes. It is a diverse group with varying aetiology, diagnosis and management. The differential diagnosis should take into account, among other things, contact with chemicals, the presence of Raynaud's phenomenon, capillaroscopic changes, comorbidities and abnormalities in laboratory tests. Scleroderma-like syndromes are particularly supported by the absence of Raynaud's phenomenon and antinuclear antibodies and the normal appearance of capillaries. Performing a skin biopsy can lead closer to an appropriate diagnosis. [ABSTRACT FROM AUTHOR]

The article focuses on the cancer screening and surveillance strategies for patients with Werner syndrome (WS), a rare premature aging disorder. Topics include the higher incidence of non-epithelial and epithelial cancers in WS, the importance of early cancer detection and treatment, and the proposed guidelines for screening using non-invasive methods like ultrasound and MRI rather than X-rays.

Werner syndrome (WS) is a rare genetic disease in humans, caused by mutations in the WRN gene that encodes a protein containing helicase and exonuclease domains. WS is characterized by symptoms of accelerated aging in multiple tissues and organs, involving increased risk of cancer, heart failure, and metabolic dysfunction. These conditions ultimately lead to the premature mortality of patients with WS. In this study, using the null mutant flies (WRNexo Δ ) for the gene WRNexo (CG7670), homologous to the exonuclease domain of WRN in humans, we examined how diets affect the lifespan, stress resistance, and sleep/wake patterns of a Drosophila model of WS. We observed that dietary restriction (DR), one of the most robust nongenetic interventions to extend lifespan in animal models, failed to extend the lifespan of WRNexo Δ mutant flies and even had a detrimental effect in females. Interestingly, the mean lifespan of WRNexo Δ mutant flies was not reduced on a protein-rich diet compared to that of wild-type (WT) flies. Compared to WT control flies, the mutant flies also exhibited altered responses to DR in their resistance to starvation and oxidative stress, as well as changes in sleep/wake patterns. These findings show that the WRN protein is necessary for mediating the effects of DR and suggest that the exonuclease domain of WRN plays an important role in metabolism in addition to its primary role in DNA-repair and genome stability. [ABSTRACT FROM AUTHOR]

Purpose: Werner syndrome (WS) is a rare autosomal recessive genetic disease caused by mutations in the WRN gene, and it is characterized by multiple manifestations corresponding to early-onset aging. This study reports the case of a WS patient with a novel WRN mutation. Patient and methods: A 36-year-old male patient with WS was evaluated after approval from the local ethics committee. The clinical and biochemical findings of the patient were described. Peripheral blood sample was collected to extract genomic DNA for WRN gene exome sequencing. The three-dimensional (3D) protein structural prediction analysis was performed via the AlphaFold 2.2 program and PyMol software. Results: We report the case of a clinically diagnosed WS patient with consanguineous parents who presented with complex manifestations including early-onset diabetes mellitus, binocular cataracts, cerebral infarction, cerebral atherosclerosis, hypertension, dyslipidemia, hypothyroidism, and suspected meningioma, accompanied by short stature, gray hair, rough skin with subcutaneous fat atrophy, a high-pitched voice, palmoplantar keratoderma, bilateral flat feet, and an indolent deep ulceration on the foot. Exome sequencing identified a novel homozygous frameshift mutation in the WRN gene, c.666-669 del TATT, p.I223fs. The 3D structure prediction showed that premature termination and significant structural changes could occur in the mutant WRN protein. Conclusion: We identified a novel homozygous frameshift mutation, p.I223fs, in WRN in a Chinese patient with WS, expanding the spectrum of mutations in WS. [ABSTRACT FROM AUTHOR]

According to current views the major hallmarks of physiological aging may be subdivided into three categories, primary causes of cellular damage (genomic instability, telomere attrition, loss of proteostasis, epigenetic alterations and compromised macroautophagy), antagonistic hallmarks that represent response to damage (deregulated nutrient sensing, cellular senescence, mitochondrial dysfunction) and integrative hallmarks that represent culprits of the phenotype (stem cell exhaustion, altered intercellular communication, chronic inflammation, dysbiosis). In contrast to physiological aging, premature aging diseases are driven by one or two distinct primary causes of aging, such as genomic instability in the case of Werner syndrome (WS), each displaying other hallmarks of aging to a variable extent. In this review we will focus on primary causes of well-investigated premature aging diseases Hutchinson-Gilford progeria syndrome (HGPS), WS, and Cockayne syndrome (CS) and for each provide an overview of reported aging hallmarks to elucidate resemblance to physiological aging on the mechanistic level and in the context of characteristic age-related diseases. Ubiquitous and tissue specific animal models of premature aging diseases will be discussed as useful tools to decipher fundamental aging- related mechanisms and develop intervention strategies to combat premature aging and age-related diseases. [ABSTRACT FROM AUTHOR]

Anti‐aging and tumorigenesis share common genes and pathways, and thus targeting these genes as part of anti‐aging interventions carries the risk of tumorigenesis. It is essential to understand the gene signatures that balance tumorigenesis and aging. To achieve this goal, we analyzed RNA‐sequencing data from three non‐tumorigenic immortalized cell lines that spontaneously escaped from senescence. By single sample gene set enrichment assay (ssGSEA) and GSEA analysis, we found that both cell growth signaling (E2F targets, MYC targets) and tumor surveillance mechanisms (DNA repair, G2M checkpoint, mitotic spindle) were up‐regulated in all three cell lines, suggesting that these genes are potential signatures for non‐tumorigenic immortalization. Further analysis revealed that the 182 commonly up‐regulated genes in these three cell lines overlapped with the DREAM/G2M pathway, which is known to be the upstream regulator of E2F, Myc targets, DNA repair, G2M checkpoint and mitotic spindle pathways in its cell cycle activation or inhibitory form. By western blotting, quantitative PCR and co‐immunoprecipitation, we verified that both forms of the DREAM pathway are up‐regulated in all three cell lines; this pathway facilitates control of cell cycle progression, supporting a new mechanism for non‐tumorigenic immortalization. Thus, we propose that the DREAM/G2M pathway plays important dual roles with respect to preventing tumorigenesis in the process of immortalization. Our data might serve as the basis for the identification of new signature pathways or gene biomarkers for non‐tumorigenic immortalization, and may aid in the discovery of new targets for tumor‐free anti‐aging drug screening.

Abstract Background Metabolic dysfunction is one of the main symptoms of Werner syndrome (WS); however, the underlying mechanisms remain unclear. Here, we report that loss of WRN accelerates adipogenesis at an early stage both in vitro (stem cells) and in vivo (zebrafish). Moreover, WRN depletion causes a transient upregulation of late-stage of adipocyte-specific genes at an early stage. Methods In an in vivo study, we generated wrn −/− mutant zebrafish and performed histological stain and Oil Red O staining to assess the fat metabolism. In an in vitro study, we used RNA-seq and ATAC-seq to profile the transcriptional features and chromatin accessibility in WRN depleted adipocytes. Moreover, we performed ChIP-seq to further study the regulatory mechanisms of metabolic dysfunction in WS. Results Our findings show that mechanistically WRN deficiency causes SMARCA5 upregulation. SMARCA5 is crucial in chromatin remodeling and gene regulation. Additionally, rescuing WRN could normalize SMARCA5 expression and adipocyte differentiation. Moreover, we find that nicotinamide riboside (NR) supplementation restores adipocyte metabolism in both stem cells and zebrafish models. Conclusions Our findings unravel a new mechanism for the influence of WRN in the early stage of adipogenesis and provide a possible treatment for metabolic dysfunction in WS. These data provide promising insights into potential therapeutics for ageing and ageing-related diseases.

Anti‐aging and tumorigenesis share common genes and pathways, and thus targeting these genes as part of anti‐aging interventions carries the risk of tumorigenesis. It is essential to understand the gene signatures that balance tumorigenesis and aging. To achieve this goal, we analyzed RNA‐sequencing data from three non‐tumorigenic immortalized cell lines that spontaneously escaped from senescence. By single sample gene set enrichment assay (ssGSEA) and GSEA analysis, we found that both cell growth signaling (E2F targets, MYC targets) and tumor surveillance mechanisms (DNA repair, G2M checkpoint, mitotic spindle) were up‐regulated in all three cell lines, suggesting that these genes are potential signatures for non‐tumorigenic immortalization. Further analysis revealed that the 182 commonly up‐regulated genes in these three cell lines overlapped with the DREAM/G2M pathway, which is known to be the upstream regulator of E2F, Myc targets, DNA repair, G2M checkpoint and mitotic spindle pathways in its cell cycle activation or inhibitory form. By western blotting, quantitative PCR and co‐immunoprecipitation, we verified that both forms of the DREAM pathway are up‐regulated in all three cell lines; this pathway facilitates control of cell cycle progression, supporting a new mechanism for non‐tumorigenic immortalization. Thus, we propose that the DREAM/G2M pathway plays important dual roles with respect to preventing tumorigenesis in the process of immortalization. Our data might serve as the basis for the identification of new signature pathways or gene biomarkers for non‐tumorigenic immortalization, and may aid in the discovery of new targets for tumor‐free anti‐aging drug screening. [ABSTRACT FROM AUTHOR]

Background: Metabolic dysfunction is one of the main symptoms of Werner syndrome (WS); however, the underlying mechanisms remain unclear. Here, we report that loss of WRN accelerates adipogenesis at an early stage both in vitro (stem cells) and in vivo (zebrafish). Moreover, WRN depletion causes a transient upregulation of late-stage of adipocyte-specific genes at an early stage. Methods: In an in vivo study, we generated wrn−/− mutant zebrafish and performed histological stain and Oil Red O staining to assess the fat metabolism. In an in vitro study, we used RNA-seq and ATAC-seq to profile the transcriptional features and chromatin accessibility in WRN depleted adipocytes. Moreover, we performed ChIP-seq to further study the regulatory mechanisms of metabolic dysfunction in WS. Results: Our findings show that mechanistically WRN deficiency causes SMARCA5 upregulation. SMARCA5 is crucial in chromatin remodeling and gene regulation. Additionally, rescuing WRN could normalize SMARCA5 expression and adipocyte differentiation. Moreover, we find that nicotinamide riboside (NR) supplementation restores adipocyte metabolism in both stem cells and zebrafish models. Conclusions: Our findings unravel a new mechanism for the influence of WRN in the early stage of adipogenesis and provide a possible treatment for metabolic dysfunction in WS. These data provide promising insights into potential therapeutics for ageing and ageing-related diseases. [ABSTRACT FROM AUTHOR]

Aim: Whether sex differences exist in hereditary progeroid syndromes remains unclear. In this study, we investigated sex differences in patients with Werner syndrome (WS), a model of human aging, using patient data at the time of diagnosis. Methods: The presence of six cardinal signs in the diagnostic criteria was retrospectively evaluated. Results: We found that the percentage of patients with all cardinal signs was higher in males than in females (54.2% vs. 21.2%). By the age of 40 years, 57.1% of male patients with WS presented with all the cardinal signs, whereas none of the female patients developed all of them. In particular, the frequency of having a high‐pitched, hoarse voice, a characteristic of WS, was lower in female patients. The positive and negative predictive values for clinical diagnosis were 100% for males and females, indicating the helpfulness of diagnostic criteria regardless of sex. More female patients than male (86.7% vs. 64%) required genetic testing for their diagnosis because their clinical symptoms were insufficient, suggesting the importance of genetic testing for females even if they do not show typical symptoms of WS. Finally, the frequency of abnormal voice was lower in patients with WS harboring the c.3139‐1G > C homozygous mutation. Conclusion: These results indicate, for the first time, that there are sex differences in the phenotypes of hereditary progeroid syndromes. The analysis of this mechanism in this human model of aging may lead to the elucidation of sex differences in the various symptoms of normal human aging. Geriatr Gerontol Int 2024; 24: 161–167. [ABSTRACT FROM AUTHOR]

Progeroid syndromes are characterized by clinical signs of premature ageing, which may contain several diseases such as Werner syndrome, Bloom syndrome, Rothmund-Thomson syndrome, Hutchinson-Gilford progeria syndrome, and Cockayne syndrome. These disorders may also exhibit some pathological involvements reminiscent of primary mitochondrial diseases. Emerging evidence has linked mitochondria even to physiological ageing. In addition, alterations in the maintenance pathway of mitochondria have been also deliberated as relevant in age-related diseases. In particular, mitophagy and its regulatory pathway might be key process for the homeostasis of mitochondria. Therefore, chronic DNA damage and/or the activation of poly[adenosine diphosphate (ADP)-ribose] polymerase 1 (PARP1) could be a threat to the mitochondrial alterations. The PARP1 is an enzyme responding to the DNA damage, which might be also involved in the mitophagy. Interestingly, the PARP1 has been reported to play an important role in the longevity of lifespan, which has attracted growing attention with the social development. This review may provide a rationalized overview of the involvement of mitochondrial oxidative stresses in genetically defined accelerated ageing, progeroid syndromes, physiological ageing, and/or age-related diseases for the innovative therapeutic approaches.

Werner syndrome (WS) is an autosomal recessive syndrome characterized by genomic instability that affects multiple body systems. The characteristic features of the disease include growth retardation, short stature, alopecia, scleroderma, atrophic skin with ulcerations, infertility, cataracts, premature arteriolosclerosis, diabetes, osteoporosis, and increased risk of malignancies. Werner syndrome protein (WRN) protein deficiency in this disease causes changes in gene expression, similar to those observed in normal aging. As the median age of death in WS is the fourth or fifth decade of life, early diagnosis leads to a better screening opportunity for malignancies. Herein, we present a 28-year-old woman who presented with growth arrest, dyspigmentation, and acroosteolysis and was later diagnosed with Werner syndrome.

This review starts off with the first germline homozygous variants of the Nucleoporin 98 gene (NUP98) in siblings whose clinical presentation recalls Rothmund–Thomson (RTS) and Werner (WS) syndromes. The progeroid phenotype caused by a gene associated with haematological malignancies and neurodegenerative disorders primed the search for interplay between caretakers involved in genome instability syndromes and Nuclear Pore Complex (NPC) components. In the context of basic information on NPC architecture and functions, we discuss the studies on the interdependence of caretakers and gatekeepers in WS and Hereditary Fibrosing Poikiloderma (POIKTMP), both entering in differential diagnosis with RTS. In WS, the WRN/WRNIP complex interacts with nucleoporins of the Y-complex and NDC1 altering NPC architecture. In POIKTMP, the mutated FAM111B, recruited by the Y-complex’s SEC13 and NUP96, interacts with several Nups safeguarding NPC structure. The linkage of both defective caretakers to the NPC highlights the attempt to activate a repair hub at the nuclear periphery to restore the DNA damage. The two separate WS and POIKTMP syndromes are drawn close by the interaction of their damage sensors with the NPC and by the shared hallmark of short fragile telomeres disclosing a major role of both caretakers in telomere maintenance.

Werner syndrome (WS) is an autosomal recessive disease caused by loss of function of WRN. WS is a segmental progeroid disease and shows early onset or increased frequency of many characteristics of normal aging. WRN possesses helicase, annealing, strand exchange, and exonuclease activities and acts on a variety of DNA substrates, even complex replication and recombination intermediates. Here, we review the genetics, biochemistry, and probably physiological functions of the WRN protein. Although its precise role is unclear, evidence suggests WRN plays a role in pathways that respond to replication stress and maintain genome stability particularly in telomeric regions.

James German’s work to establish the natural history and cancer risk associated with Bloom syndrome (BS) has had a strong influence on the generation of scientists and clinicians working to understand other RECQ deficiencies and heritable cancer predisposition syndromes. I summarize work by us and others below, inspired by James German’s precedents with BS, to understand and compare BS with the other heritable RECQ deficiency syndromes with a focus on Werner syndrome (WS). What we know, unanswered questions and new opportunities are discussed, as are potential ways to treat or modify WS-associated disease mechanisms and pathways.

Abstract Background Pathogenic mutations in WRN are a cause of premature aging disease Werner syndrome (WS). Besides accelerated aging phenotypes and cancer predisposition, patients with WS also display underdevelopment in the skeletal system, characterized by short stature, light body weight and unusually thin extremities. The reasons for these developmental defects are not completely understood and the underlying molecular mechanism remains to be elucidated. Results In this study, WRN was found to modulate transcription of short stature homeobox gene SHOX. Loss of WRN resulted in insufficient expression of SHOX, the gene dose of which is critical for driving chondrocyte differentiation. WRN could bind the G-quadruplex (G4) structures in the SHOX promoter and stimulate transcription. Aberrant formation of G4 structures in WRN-deficient cells impeded normal transcription of SHOX, thus resulting in impaired chondrogenesis. Chondrogenesis could be rescued by overexpression of WRN helicase or SHOX, suggesting that SHOX is a downstream target of WRN. Gene editing of the G4 structures in the SHOX promoter could increase SHOX expression, therefore rescuing the impaired chondrogenesis in WRN-deficient cells. Conclusions Our data suggest that dysgenesis of the developing bone in WS might be caused by SHOX insufficiency. Aberrant formation of G4 structures in SHOX promoter suppresses SHOX expression and impairs chondrogenesis. Targeted mutagenesis in the G4 structures enhances SHOX expression and thus providing an opportunity to rescue the chondrogenic defect.

Abstract Background Werner syndrome is a rare, autosomal recessive disorder characterised by premature aging. It is a typical hereditary progeroid syndrome that can be difficult to diagnose owing to its rarity and the similarity of some of its symptoms, such as juvenile cataracts, to other common ophthalmologic conditions. Early onset of bilateral cataracts is currently used as the ophthalmological feature for Werner syndrome; however, ophthalmologists often find performing a detailed examination of the medical history and genetic testing for Werner syndrome at the time of an ophthalmologic consultation challenging. If a unique ocular finding was observed on ocular examinations in cases of juvenile bilateral cataracts, we could consider Werner syndrome as a differential diagnosis. Case presentation We documented the cases of three patients with Werner syndrome in whom thinning of the retina in the retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) were observed using optical coherence tomography (OCT). Visual field tests revealed the loss of visual field mainly owing to glaucoma. The thinnig of the choroidal thickness (CT) in three patients was also observed using enhanced depth imaging (EDI)-OCT. Conclusions Three patients have thinning of the RNFL, GCC, and choroidal thickness and the loss of visual field. These findings suggest the need for including Werner syndrome in the differential diagnosis when patients presenting with juvenile cataracts of unknown cause also show abnormal retinal and choroidal thinning in the OCT images.

Abstract Background Werner syndrome (WS) is an autosomal recessive premature ageing disease that causes accelerated ageing-like symptoms after puberty. Previous studies conducted in the late 2000s reported that malignant neoplasms and atherosclerotic diseases were the two leading causes of death, with life expectancies in the mid-50 s. However, the recent lifespan and cause of death in patients with WS remain unclear. Objective To clarify the latest lifespan and causes of death in patients with WS. Method We conducted a questionnaire-based survey in 2020 among the primary doctors of WS patients who were identified in previous nationwide surveys in Japan and clarified the following: the age of WS patients (age of death, if the patient had already died), sex, and cause of death. Patients who died in 2010 or earlier were excluded from the analysis. Results A total of 123 living patients were identified at the time of the survey in 2020. Fourteen WS patients died between 2011 and 2020, with a mean age of 59.0 ± 8.9 years (mean ± SD). The most common cause of death was non-epithelial tumours, accounting for eight deaths, while no patient died of atherosclerotic diseases. Conclusions Compared to previous studies, this study suggests that the lifespan of patients with WS has been extended. Although there were no deaths due to atherosclerotic diseases, non-epithelial tumours were still the leading cause of death. Further development of screening and treatment methods for these tumours is required.

Senescent cells exhibit several typical features, including the senescence-associated secretory phenotype (SASP), promoting the secretion of various inflammatory proteins and small extracellular vesicles (EVs). SASP factors cause chronic inflammation, leading to age-related diseases. Recently, therapeutic strategies targeting senescent cells, known as senolytics, have gained attention; however, noninvasive methods to detect senescent cells in living organisms have not been established. Therefore, the goal of this study was to identify novel senescent markers using small EVs (sEVs). sEVs were isolated from young and senescent fibroblasts using three different methods, including size-exclusion chromatography, affinity column for phosphatidylserine, and immunoprecipitation using antibodies against tetraspanin proteins, followed by mass spectrometry. Principal component analysis revealed that the protein composition of sEVs released from senescent cells was significantly different from that of young cells. Importantly, we identified ATP6V0D1 and RTN4 as novel markers that are frequently upregulated in sEVs from senescent and progeria cells derived from patients with Werner syndrome. Furthermore, these two proteins were significantly enriched in sEVs from the serum of aged mice. This study supports the potential use of senescent markers from sEVs to detect the presence of senescent cells in vivo. [ABSTRACT FROM AUTHOR]

Repair of genomic DNA is a fundamental housekeeping process that quietly maintains the health of our genomes. The consequences of a genetic defect affecting a component of this delicate mechanism are quite harmful, characterized by a cascade of premature aging that injures a variety of organs, including the nervous system. One part of the nervous system that is impaired in certain DNA repair disorders is the peripheral nerve. Chronic motor, sensory, and sensorimotor polyneuropathies have all been observed in affected individuals, with specific physiologies associated with different categories of DNA repair disorders. Cockayne syndrome has classically been linked to demyelinating polyneuropathies, whereas xeroderma pigmentosum has long been associated with axonal polyneuropathies. Three additional recessive DNA repair disorders are associated with neuropathies, including trichothiodystrophy, Werner syndrome, and ataxia‐telangiectasia. Although plausible biological explanations exist for why the peripheral nerves are specifically vulnerable to impairments of DNA repair, specific mechanisms such as oxidative stress remain largely unexplored in this context, and bear further study. It is also unclear why different DNA repair disorders manifest with different types of neuropathy, and why neuropathy is not universally present in those diseases. Longitudinal physiological monitoring of these neuropathies with serial electrodiagnostic studies may provide valuable noninvasive outcome data in the context of future natural history studies, and thus the responses of these neuropathies may become sentinel outcome measures for future clinical trials of treatments currently in development such as adeno‐associated virus gene replacement therapies. [ABSTRACT FROM AUTHOR]

Interstitial lung disease (ILD) is a condition affecting the lung parenchyma by inflammation and fibrosis and can be caused by various exposures, connective tissue diseases (CTD), and genetic disorders. In this report, a family with five patients having progressive respiratory failure that begins with coughing in adolescence, followed by dyspnea and recurrent spontaneous pneumothorax, and death in early adulthood is presented. The patients were diagnosed to have ILD through clinical and radiological evaluations. Molecular genetic analyses of the family provided two homozygous rare variants in the WRN and SFXN5 genes, co‐segregating with the phenotype. The network analyses pointed out that the variant in the WRN, rather than that in the SFXN5 gene, could be the main factor in the existence of the ILD phenotype, putatively through the altered DNA repair and telomere maintenance pathways. In silico analyses suggested that the variant could affect the exonuclease activity or the stability of the WRN protein. Moreover, the adolescent‐onset pulmonary phenotype described in the case has not been reported in Werner Syndrome, the only disease known to be associated with biallelic WRN pathogenic variants. Thus, the present phenotype could be either a very atypical presentation of Werner syndrome or a new clinical entity associated with the WRN gene. [ABSTRACT FROM AUTHOR]

Background: Pathogenic mutations in WRN are a cause of premature aging disease Werner syndrome (WS). Besides accelerated aging phenotypes and cancer predisposition, patients with WS also display underdevelopment in the skeletal system, characterized by short stature, light body weight and unusually thin extremities. The reasons for these developmental defects are not completely understood and the underlying molecular mechanism remains to be elucidated. Results: In this study, WRN was found to modulate transcription of short stature homeobox gene SHOX. Loss of WRN resulted in insufficient expression of SHOX, the gene dose of which is critical for driving chondrocyte differentiation. WRN could bind the G-quadruplex (G4) structures in the SHOX promoter and stimulate transcription. Aberrant formation of G4 structures in WRN-deficient cells impeded normal transcription of SHOX, thus resulting in impaired chondrogenesis. Chondrogenesis could be rescued by overexpression of WRN helicase or SHOX, suggesting that SHOX is a downstream target of WRN. Gene editing of the G4 structures in the SHOX promoter could increase SHOX expression, therefore rescuing the impaired chondrogenesis in WRN-deficient cells. Conclusions: Our data suggest that dysgenesis of the developing bone in WS might be caused by SHOX insufficiency. Aberrant formation of G4 structures in SHOX promoter suppresses SHOX expression and impairs chondrogenesis. Targeted mutagenesis in the G4 structures enhances SHOX expression and thus providing an opportunity to rescue the chondrogenic defect. [ABSTRACT FROM AUTHOR]

Werner syndrome (WS) is a rare autosomal recessive, premature aging disorder whose clinical manifestations include short stature, bilateral cataracts, diabetes mellitus, hypertension, and atherosclerosis. WS first manifests during adolescence and patients usually die at 40–50 years of age. Only symptomatic treatment options available according to clinical manifestations. In anesthetic management, they need to be considered to elderly patients. Difficult intubation is expected and the patients are regarded as a high-risk group for anesthesia, owing to the concomitant cardiovascular and cerebrovascular disorders. The anesthetic management of WS requires a meticulous preoperative history taking, physical examination, and preparation for cardiovascular events.

Abstract Werner syndrome is a rare autosomal recessive premature progeroid syndrome caused by mutations in the WRN gene. It is characterized by early onset of age‐related diseases, such as cataracts, atherosclerosis, diabetes mellitus, osteoporosis and malignancies, in which diabetes often onset in patients’ 30–40s. Herein, we report a Chinese patient with Werner syndrome with uncommon early‐onset diabetes at 18 years‐of‐age, who had low body mass index, insulin resistance, negative antibodies of diabetes and early onset of cataracts. Genome sequencing and reverse transcription polymerase chain reaction confirm the diagnosis. A novel heterozygous splice‐site mutation in the WRN gene (c.1270‐2A>T) was identified. The present case reminds clinicians that when young diabetes patients are encountered, if they are accompanied by premature aging, attention should be paid to identifying the possibility of Werner syndrome based on diagnostic criteria.

Background: Werner syndrome is a rare, autosomal recessive disorder characterised by premature aging. It is a typical hereditary progeroid syndrome that can be difficult to diagnose owing to its rarity and the similarity of some of its symptoms, such as juvenile cataracts, to other common ophthalmologic conditions. Early onset of bilateral cataracts is currently used as the ophthalmological feature for Werner syndrome; however, ophthalmologists often find performing a detailed examination of the medical history and genetic testing for Werner syndrome at the time of an ophthalmologic consultation challenging. If a unique ocular finding was observed on ocular examinations in cases of juvenile bilateral cataracts, we could consider Werner syndrome as a differential diagnosis.  CASE PRESENTATION: We documented the cases of three patients with Werner syndrome in whom thinning of the retina in the retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) were observed using optical coherence tomography (OCT). Visual field tests revealed the loss of visual field mainly owing to glaucoma. The thinnig of the choroidal thickness (CT) in three patients was also observed using enhanced depth imaging (EDI)-OCT.Conclusions: Three patients have thinning of the RNFL, GCC, and choroidal thickness and the loss of visual field. These findings suggest the need for including Werner syndrome in the differential diagnosis when patients presenting with juvenile cataracts of unknown cause also show abnormal retinal and choroidal thinning in the OCT images. [ABSTRACT FROM AUTHOR]

• Partial lipodystrophy is an unusual presentation of Werner syndrome. • Exome analysis revealed a novel splice site variant c.2732+5G> A. • c.2732+5G> A leads to exon skipping and partially abrogates the WRN helicase domain. • The WRN gene should be included in different gene panels to prompt diagnosis. Werner syndrome is a premature ageing disorder caused by biallelic variants in the WRN gene. WRN encodes a dual DNA helicase/exonuclease enzyme. Molecular diagnosis is commonly only made at a late disease stage in the third or fourth decade, when cardinal features have become apparent. We describe a 28 year-old woman who presented with early onset diabetes associated with partial lipodystrophy, severe dyslipidaemia and rapidly progressive liver fibrosis related to non-alcoholic steatohepatitis in the absence of progeroid features. Werner syndrome was diagnosed by trio exome analysis, which revealed compound heterozygous WRN mutations: the known variant c.1290_1293del (p.Asn430Lysfs*7) and the novel intronic splice site variant c.2732+5G> A. cDNA analysis demonstrated this to lead to in-frame skipping of exon 22, predicted to delete most of the zinc binding region of the helicase domain. We suggest that including the WRN gene in genetic analysis of early onset diabetes, lipodystrophy or dyslipidaemia would allow for the opportunity to diagnose some cases of Werner syndrome long before clinical criteria are met, thereby allowing early implementation of important primary prevention interventions. [ABSTRACT FROM AUTHOR]

Werner syndrome is an autosomal recessive rare disease caused by a WRN gene mutation, which is rarely reported in the Chinese population. We report the clinical and genetic data of a Chinese patient with Werner syndrome. The proband was a 40-year-old male patient who presented with diabetic foot ulcers, accompanied by short stature, cataracts, hypogonadism, and hair thinning, and myelodysplastic syndrome (MDS) occurred after 18 months. Genetic sequencing showed there were compound heterozygous mutations as c.3384-1G>C and c.3744dupA in the WRN gene. The c.3744dupA mutation is a novel pathogenic variation for Werner syndrome. [ABSTRACT FROM AUTHOR]

Prompt diagnosis of complex phenotypes is a challenging task in clinical genetics. Whole exome sequencing has proved to be effective in solving such conditions. Here, we report on an unpredictable presentation of Werner Syndrome (WRNS) in a 12‐year‐old girl carrying a homozygous truncating variant in RECQL2, the gene mutated in WRNS, and a de novo activating missense change in PTPN11, the major Noonan syndrome gene, encoding SHP2, a protein tyrosine phosphatase positively controlling RAS function and MAPK signaling, which have tightly been associated with senescence in primary cells. All the major WRNS clinical criteria were present with an extreme precocious onset and were associated with mild intellectual disability, severe growth retardation and facial dysmorphism. Compared to primary fibroblasts from adult subjects with WRNS, proband's fibroblasts showed a dramatically reduced proliferation rate and competence, and a more accelerated senescence, in line with the anticipated WRNS features occurring in the child. In vitro functional characterization of the SHP2 mutant documented its hyperactive behavior and a significantly enhanced activation of the MAPK pathway. Based on the functional interaction of WRN and MAPK signaling in processes relevant to replicative senescence, these findings disclose a unique phenotype likely resulting from negative genetic interaction. [ABSTRACT FROM AUTHOR]

Background: Werner syndrome (WS) is an autosomal recessive premature ageing disease that causes accelerated ageing-like symptoms after puberty. Previous studies conducted in the late 2000s reported that malignant neoplasms and atherosclerotic diseases were the two leading causes of death, with life expectancies in the mid-50 s. However, the recent lifespan and cause of death in patients with WS remain unclear.Objective: To clarify the latest lifespan and causes of death in patients with WS.Method: We conducted a questionnaire-based survey in 2020 among the primary doctors of WS patients who were identified in previous nationwide surveys in Japan and clarified the following: the age of WS patients (age of death, if the patient had already died), sex, and cause of death. Patients who died in 2010 or earlier were excluded from the analysis.Results: A total of 123 living patients were identified at the time of the survey in 2020. Fourteen WS patients died between 2011 and 2020, with a mean age of 59.0 ± 8.9 years (mean ± SD). The most common cause of death was non-epithelial tumours, accounting for eight deaths, while no patient died of atherosclerotic diseases.Conclusions: Compared to previous studies, this study suggests that the lifespan of patients with WS has been extended. Although there were no deaths due to atherosclerotic diseases, non-epithelial tumours were still the leading cause of death. Further development of screening and treatment methods for these tumours is required. [ABSTRACT FROM AUTHOR]

Fabio CoppedèDepartment of Translational Research and of New Surgical and Medical Technologies, University of Pisa, Pisa, ItalyCorrespondence: Fabio CoppedèDepartment of Translational Research and of New Surgical and Medical Technologies, University of Pisa, Via Roma 55, Pisa, 56126, ItalyTel +39 050 2218544Fax +39 050 2211034Email fabio.coppede@med.unipi.itAbstract: Premature-ageing syndromes are a heterogeneous group of rare genetic disorders resembling features of accelerated ageing and resulting from mutations in genes coding for proteins required for nuclear lamina architecture, DNA repair and maintenance of genome stability, mitochondrial function and other cellular processes. Hutchinson–Gilford progeria syndrome (HGPS) and Werner syndrome (WS) are two of the best-characterized progeroid syndromes referred to as childhood- and adulthood-progeria, respectively. This article provides an updated overview of the mutations leading to HGPS, WS, and to the spectrum of premature-ageing laminopathies ranging in severity from congenital restrictive dermopathy (RD) to adult-onset atypical WS, including RD-like laminopathies, typical and atypical HGPS, more and less severe forms of mandibuloacral dysplasia (MAD), Néstor-Guillermo progeria syndrome (NGPS), atypical WS, and atypical progeroid syndromes resembling features of HGPS and/or MAD but resulting from impaired DNA repair or mitochondrial functions, including mandibular hypoplasia, deafness, progeroid features, and lipodystrophy (MDPL) syndrome and mandibuloacral dysplasia associated to MTX2 (MADaM). The overlapping signs and symptoms among different premature-ageing syndromes, resulting from both a large genetic heterogeneity and shared pathological pathways underlying these conditions, require an expert clinical evaluation in specialized centers paralleled by next-generation sequencing of panels of genes involved in these disorders in order to establish as early as possible an accurate clinical and molecular diagnosis for a proper patient management.Keywords: Hutchinson–Gilford progeria syndrome, Werner syndrome, restrictive dermopathy, mandibuloacral dysplasia, Néstor-Guillermo progeria syndrome, atypical progeroid syndromes