RESUMEN
Clear cell renal cell carcinoma (ccRCC) is characterized by near-universal loss of the short arm of chromosome 3, deleting several tumor suppressor genes. We analyzed whole genomes from 95 biopsies across 33 patients with clear cell renal cell carcinoma. We find hotspots of point mutations in the 5' UTR of TERT, targeting a MYC-MAX-MAD1 repressor associated with telomere lengthening. The most common structural abnormality generates simultaneous 3p loss and 5q gain (36% patients), typically through chromothripsis. This event occurs in childhood or adolescence, generally as the initiating event that precedes emergence of the tumor's most recent common ancestor by years to decades. Similar genomic changes drive inherited ccRCC. Modeling differences in age incidence between inherited and sporadic cancers suggests that the number of cells with 3p loss capable of initiating sporadic tumors is no more than a few hundred. Early development of ccRCC follows well-defined evolutionary trajectories, offering opportunity for early intervention.
Asunto(s)
Carcinoma de Células Renales/genética , Carcinoma de Células Renales/patología , Progresión de la Enfermedad , Neoplasias Renales/genética , Neoplasias Renales/patología , Mutación , Regiones no Traducidas 5' , Adulto , Anciano , Anciano de 80 o más Años , Cromosomas Humanos Par 3 , Cromosomas Humanos Par 5 , Femenino , Dosificación de Gen , Genoma Humano , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Telomerasa/genética , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/genéticaRESUMEN
The MCM motor of the replicative helicase is loaded onto origin DNA as an inactive double hexamer before replication initiation. Recruitment of activators GINS and Cdc45 upon S-phase transition promotes the assembly of two active CMG helicases. Although work with yeast established the mechanism for origin activation, how CMG is formed in higher eukaryotes is poorly understood. Metazoan Downstream neighbor of Son (DONSON) has recently been shown to deliver GINS to MCM during CMG assembly. What impact this has on the MCM double hexamer is unknown. Here, we used cryoelectron microscopy (cryo-EM) on proteins isolated from replicating Xenopus egg extracts to identify a double CMG complex bridged by a DONSON dimer. We find that tethering elements mediating complex formation are essential for replication. DONSON reconfigures the MCM motors in the double CMG, and primordial dwarfism patients' mutations disrupting DONSON dimerization affect GINS and MCM engagement in human cells and DNA synthesis in Xenopus egg extracts.
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Proteínas de Ciclo Celular , ADN Helicasas , Proteínas Nucleares , Animales , Humanos , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/metabolismo , Microscopía por Crioelectrón , ADN/genética , ADN/metabolismo , ADN Helicasas/metabolismo , Replicación del ADN , Proteínas de Mantenimiento de Minicromosoma/genética , Proteínas de Mantenimiento de Minicromosoma/metabolismo , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Saccharomyces cerevisiae/genética , Activación EnzimáticaRESUMEN
The 53BP1-RIF1-shieldin pathway maintains genome stability by suppressing nucleolytic degradation of DNA ends at double-strand breaks (DSBs). Although RIF1 interacts with damaged chromatin via phospho-53BP1 and facilitates recruitment of the shieldin complex to DSBs, it is unclear whether other regulatory cues contribute to this response. Here, we implicate methylation of histone H3 at lysine 4 by SETD1A-BOD1L in the recruitment of RIF1 to DSBs. Compromising SETD1A or BOD1L expression or deregulating H3K4 methylation allows uncontrolled resection of DNA ends, impairs end-joining of dysfunctional telomeres, and abrogates class switch recombination. Moreover, defects in RIF1 localization to DSBs are evident in patient cells bearing loss-of-function mutations in SETD1A. Loss of SETD1A-dependent RIF1 recruitment in BRCA1-deficient cells restores homologous recombination and leads to resistance to poly(ADP-ribose)polymerase inhibition, reinforcing the clinical relevance of these observations. Mechanistically, RIF1 binds directly to methylated H3K4, facilitating its recruitment to, or stabilization at, DSBs.
Asunto(s)
Roturas del ADN de Doble Cadena , Proteínas de Unión a Telómeros , Proteína BRCA1/genética , ADN/metabolismo , Reparación del ADN por Unión de Extremidades , Reparación del ADN , N-Metiltransferasa de Histona-Lisina/genética , N-Metiltransferasa de Histona-Lisina/metabolismo , Humanos , Metilación , Proteínas de Unión a Telómeros/genética , Proteínas de Unión a Telómeros/metabolismo , Proteína 1 de Unión al Supresor Tumoral P53/genética , Proteína 1 de Unión al Supresor Tumoral P53/metabolismoRESUMEN
Large-scale human genetic data1-3 have shown that cancer mutations display strong tissue-selectivity, but how this selectivity arises remains unclear. Here, using experimental models, functional genomics and analyses of patient samples, we demonstrate that the lineage transcription factor paired box 8 (PAX8) is required for oncogenic signalling by two common genetic alterations that cause clear cell renal cell carcinoma (ccRCC) in humans: the germline variant rs7948643 at 11q13.3 and somatic inactivation of the von Hippel-Lindau tumour suppressor (VHL)4-6. VHL loss, which is observed in about 90% of ccRCCs, can lead to hypoxia-inducible factor 2α (HIF2A) stabilization6,7. We show that HIF2A is preferentially recruited to PAX8-bound transcriptional enhancers, including a pro-tumorigenic cyclin D1 (CCND1) enhancer that is controlled by PAX8 and HIF2A. The ccRCC-protective allele C at rs7948643 inhibits PAX8 binding at this enhancer and downstream activation of CCND1 expression. Co-option of a PAX8-dependent physiological programme that supports the proliferation of normal renal epithelial cells is also required for MYC expression from the ccRCC metastasis-associated amplicons at 8q21.3-q24.3 (ref. 8). These results demonstrate that transcriptional lineage factors are essential for oncogenic signalling and that they mediate tissue-specific cancer risk associated with somatic and inherited genetic variants.
Asunto(s)
Carcinogénesis , Neoplasias Renales , Factor de Transcripción PAX8 , Transducción de Señal , Alelos , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Carcinogénesis/genética , Carcinoma de Células Renales/metabolismo , Carcinoma de Células Renales/patología , Ciclina D1/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Riñón/metabolismo , Riñón/patología , Neoplasias Renales/metabolismo , Neoplasias Renales/patología , Mutación , Factor de Transcripción PAX8/genética , Factor de Transcripción PAX8/metabolismo , Proteínas Proto-Oncogénicas c-myc/genética , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/genéticaRESUMEN
Telomere maintenance 2 (TELO2), Tel2 interacting protein 2 (TTI2), and Tel2 interacting protein 1 (TTI1) are the three components of the conserved Triple T (TTT) complex that modulates activity of phosphatidylinositol 3-kinase-related protein kinases (PIKKs), including mTOR, ATM, and ATR, by regulating the assembly of mTOR complex 1 (mTORC1). The TTT complex is essential for the expression, maturation, and stability of ATM and ATR in response to DNA damage. TELO2- and TTI2-related bi-allelic autosomal-recessive (AR) encephalopathies have been described in individuals with moderate to severe intellectual disability (ID), short stature, postnatal microcephaly, and a movement disorder (in the case of variants within TELO2). We present clinical, genomic, and functional data from 11 individuals in 9 unrelated families with bi-allelic variants in TTI1. All present with ID, and most with microcephaly, short stature, and a movement disorder. Functional studies performed in HEK293T cell lines and fibroblasts and lymphoblastoid cells derived from 4 unrelated individuals showed impairment of the TTT complex and of mTOR pathway activity which is improved by treatment with Rapamycin. Our data delineate a TTI1-related neurodevelopmental disorder and expand the group of disorders related to the TTT complex.
Asunto(s)
Microcefalia , Trastornos del Movimiento , Trastornos del Neurodesarrollo , Humanos , Péptidos y Proteínas de Señalización Intracelular , Células HEK293 , Serina-Treonina Quinasas TORRESUMEN
Components of the Fanconi anemia and homologous recombination pathways play a vital role in protecting newly replicated DNA from uncontrolled nucleolytic degradation, safeguarding genome stability. Here we report that histone methylation by the lysine methyltransferase SETD1A is crucial for protecting stalled replication forks from deleterious resection. Depletion of SETD1A sensitizes cells to replication stress and leads to uncontrolled DNA2-dependent resection of damaged replication forks. The ability of SETD1A to prevent degradation of these structures is mediated by its ability to catalyze methylation on Lys4 of histone H3 (H3K4) at replication forks, which enhances FANCD2-dependent histone chaperone activity. Suppressing H3K4 methylation or expression of a chaperone-defective FANCD2 mutant leads to loss of RAD51 nucleofilament stability and severe nucleolytic degradation of replication forks. Our work identifies epigenetic modification and histone mobility as critical regulatory mechanisms in maintaining genome stability by restraining nucleases from irreparably damaging stalled replication forks.
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ADN/biosíntesis , Proteína del Grupo de Complementación D2 de la Anemia de Fanconi/metabolismo , N-Metiltransferasa de Histona-Lisina/metabolismo , Histonas/metabolismo , Chaperonas Moleculares/metabolismo , Nucleosomas/metabolismo , Células A549 , ADN/genética , Replicación del ADN/fisiología , Epigénesis Genética/fisiología , Proteína del Grupo de Complementación D2 de la Anemia de Fanconi/genética , Células HeLa , N-Metiltransferasa de Histona-Lisina/genética , Histonas/genética , Humanos , Metilación , Chaperonas Moleculares/genética , Nucleosomas/genética , Recombinasa Rad51/genética , Recombinasa Rad51/metabolismoRESUMEN
The integrity of genomes is constantly threatened by problems encountered by the replication fork. BRCA1, BRCA2 and a subset of Fanconi anaemia proteins protect stalled replication forks from degradation by nucleases, through pathways that involve RAD51. The contribution and regulation of BRCA1 in replication fork protection, and how this role relates to its role in homologous recombination, is unclear. Here we show that BRCA1 in complex with BARD1, and not the canonical BRCA1-PALB2 interaction, is required for fork protection. BRCA1-BARD1 is regulated by a conformational change mediated by the phosphorylation-directed prolyl isomerase PIN1. PIN1 activity enhances BRCA1-BARD1 interaction with RAD51, thereby increasing the presence of RAD51 at stalled replication structures. We identify genetic variants of BRCA1-BARD1 in patients with cancer that exhibit poor protection of nascent strands but retain homologous recombination proficiency, thus defining domains of BRCA1-BARD1 that are required for fork protection and associated with cancer development. Together, these findings reveal a BRCA1-mediated pathway that governs replication fork protection.
Asunto(s)
Proteína BRCA1/química , Proteína BRCA1/metabolismo , Replicación del ADN , Proteínas Supresoras de Tumor/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Proteína BRCA1/genética , Línea Celular Tumoral , Replicación del ADN/genética , Inestabilidad Genómica/genética , Humanos , Isomerismo , Mutación , Peptidilprolil Isomerasa de Interacción con NIMA/metabolismo , Fosforilación , Fosfoserina/metabolismo , Unión Proteica , Recombinasa Rad51/metabolismoRESUMEN
Protein post-translation modification plays an important role in regulating DNA repair; however, the role of arginine methylation in this process is poorly understood. Here we identify the arginine methyltransferase PRMT5 as a key regulator of homologous recombination (HR)-mediated double-strand break (DSB) repair, which is mediated through its ability to methylate RUVBL1, a cofactor of the TIP60 complex. We show that PRMT5 targets RUVBL1 for methylation at position R205, which facilitates TIP60-dependent mobilization of 53BP1 from DNA breaks, promoting HR. Mechanistically, we demonstrate that PRMT5-directed methylation of RUVBL1 is critically required for the acetyltransferase activity of TIP60, promoting histone H4K16 acetylation, which facilities 53BP1 displacement from DSBs. Interestingly, RUVBL1 methylation did not affect the ability of TIP60 to facilitate ATM activation. Taken together, our findings reveal the importance of PRMT5-mediated arginine methylation during DSB repair pathway choice through its ability to regulate acetylation-dependent control of 53BP1 localization.
Asunto(s)
Proteínas Portadoras/metabolismo , Roturas del ADN de Doble Cadena , ADN Helicasas/metabolismo , Histona Acetiltransferasas/metabolismo , Procesamiento Proteico-Postraduccional , Proteína-Arginina N-Metiltransferasas/metabolismo , Reparación del ADN por Recombinación , ATPasas Asociadas con Actividades Celulares Diversas , Acetilación , Animales , Arginina , Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Proteínas Portadoras/genética , ADN Helicasas/genética , Inestabilidad Genómica , Células HEK293 , Células HeLa , Histona Acetiltransferasas/genética , Histonas/metabolismo , Humanos , Lisina Acetiltransferasa 5 , Metilación , Ratones , Ratones Transgénicos , Proteína-Arginina N-Metiltransferasas/genética , Interferencia de ARN , Factores de Tiempo , Transfección , Proteína 1 de Unión al Supresor Tumoral P53/genética , Proteína 1 de Unión al Supresor Tumoral P53/metabolismoRESUMEN
Maintenance of genome stability is of paramount importance for the survival of an organism. However, genomic integrity is constantly being challenged by various endogenous and exogenous processes that damage DNA. Therefore, cells are heavily reliant on DNA repair pathways that have evolved to deal with every type of genotoxic insult that threatens to compromise genome stability. Notably, inherited mutations in genes encoding proteins involved in these protective pathways trigger the onset of disease that is driven by chromosome instability e.g. neurodevelopmental abnormalities, neurodegeneration, premature ageing, immunodeficiency and cancer development. The ability of cells to regulate the recruitment of specific DNA repair proteins to sites of DNA damage is extremely complex but is primarily mediated by protein post-translational modifications (PTMs). Ubiquitylation is one such PTM, which controls genome stability by regulating protein localisation, protein turnover, protein-protein interactions and intra-cellular signalling. Over the past two decades, numerous ubiquitin (Ub) E3 ligases have been identified to play a crucial role not only in the initiation of DNA replication and DNA damage repair but also in the efficient termination of these processes. In this review, we discuss our current understanding of how different Ub E3 ligases (RNF168, TRAIP, HUWE1, TRIP12, FANCL, BRCA1, RFWD3) function to regulate DNA repair and replication and the pathological consequences arising from inheriting deleterious mutations that compromise the Ub-dependent DNA damage response.
Asunto(s)
Daño del ADN , Reparación del ADN , Replicación del ADN , Ubiquitina-Proteína Ligasas , Humanos , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitinación , Neoplasias/genética , Neoplasias/metabolismo , Inestabilidad Genómica , Procesamiento Proteico-Postraduccional , Animales , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismoRESUMEN
Accurate genome replication is essential for all life and a key mechanism of disease prevention, underpinned by the ability of cells to respond to replicative stress (RS) and protect replication forks. These responses rely on the formation of Replication Protein A (RPA)-single stranded (ss) DNA complexes, yet this process remains largely uncharacterized. Here, we establish that actin nucleation-promoting factors (NPFs) associate with replication forks, promote efficient DNA replication and facilitate association of RPA with ssDNA at sites of RS. Accordingly, their loss leads to deprotection of ssDNA at perturbed forks, impaired ATR activation, global replication defects and fork collapse. Supplying an excess of RPA restores RPA foci formation and fork protection, suggesting a chaperoning role for actin nucleators (ANs) (i.e. Arp2/3, DIAPH1) and NPFs (i.e, WASp, N-WASp) in regulating RPA availability upon RS. We also discover that ß-actin interacts with RPA directly in vitro, and in vivo a hyper-depolymerizing ß-actin mutant displays a heightened association with RPA and the same dysfunctional replication phenotypes as loss of ANs/NPFs, which contrasts with the phenotype of a hyper-polymerizing ß-actin mutant. Thus, we identify components of actin polymerization pathways that are essential for preventing ectopic nucleolytic degradation of perturbed forks by modulating RPA activity.
Asunto(s)
Actinas , Replicación del ADN , Actinas/genética , Proteína de Replicación A/genética , Proteína de Replicación A/metabolismo , ADN de Cadena Simple/genética , Chaperonas Moleculares/genéticaRESUMEN
BRCA1 mutations are associated with increased breast and ovarian cancer risk. BRCA1-mutant tumors are high-grade, recurrent, and often become resistant to standard therapies. Herein, we performed a targeted CRISPR-Cas9 screen and identified MEPCE, a methylphosphate capping enzyme, as a synthetic lethal interactor of BRCA1. Mechanistically, we demonstrate that depletion of MEPCE in a BRCA1-deficient setting led to dysregulated RNA polymerase II (RNAPII) promoter-proximal pausing, R-loop accumulation, and replication stress, contributing to transcription-replication collisions. These collisions compromise genomic integrity resulting in loss of viability of BRCA1-deficient cells. We also extend these findings to another RNAPII-regulating factor, PAF1. This study identifies a new class of synthetic lethal partners of BRCA1 that exploit the RNAPII pausing regulation and highlight the untapped potential of transcription-replication collision-inducing factors as unique potential therapeutic targets for treating cancers associated with BRCA1 mutations.
Asunto(s)
Proteína BRCA1 , Replicación del ADN , Síndrome de Cáncer de Mama y Ovario Hereditario , Mutación , Transcripción Genética , Humanos , Proteína BRCA1/deficiencia , Proteína BRCA1/genética , Replicación del ADN/genética , Síndrome de Cáncer de Mama y Ovario Hereditario/genética , Síndrome de Cáncer de Mama y Ovario Hereditario/patología , Síndrome de Cáncer de Mama y Ovario Hereditario/fisiopatología , ARN Polimerasa II/metabolismo , Transcripción Genética/genética , Regiones Promotoras Genéticas , Metiltransferasas/deficiencia , Metiltransferasas/genética , Estructuras R-Loop , Muerte CelularRESUMEN
Breast cancer linked with BRCA1/2 mutations commonly recur and resist current therapies, including PARP inhibitors. Given the lack of effective targeted therapies for BRCA1-mutant cancers, we sought to identify novel targets to selectively kill these cancers. Here, we report that loss of RNF8 significantly protects Brca1-mutant mice against mammary tumorigenesis. RNF8 deficiency in human BRCA1-mutant breast cancer cells was found to promote R-loop accumulation and replication fork instability, leading to increased DNA damage, senescence, and synthetic lethality. Mechanistically, RNF8 interacts with XRN2, which is crucial for transcription termination and R-loop resolution. We report that RNF8 ubiquitylates XRN2 to facilitate its recruitment to R-loop-prone genomic loci and that RNF8 deficiency in BRCA1-mutant breast cancer cells decreases XRN2 occupancy at R-loop-prone sites, thereby promoting R-loop accumulation, transcription-replication collisions, excessive genomic instability, and cancer cell death. Collectively, our work identifies a synthetic lethal interaction between RNF8 and BRCA1, which is mediated by a pathological accumulation of R-loops.
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Proteína BRCA1 , Neoplasias de la Mama , Animales , Femenino , Humanos , Ratones , Proteína BRCA1/metabolismo , Proteína BRCA2/genética , Neoplasias de la Mama/genética , Daño del ADN , Proteínas de Unión al ADN/metabolismo , Exorribonucleasas/metabolismo , Inestabilidad Genómica , Recurrencia Local de Neoplasia , Estructuras R-Loop , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , UbiquitinaciónRESUMEN
Using multipathogen PCR testing, we identified 195 students with adenovirus type 4 infections on a university campus in South Carolina, USA, during January-May 2022. We co-detected other respiratory viruses in 43 (22%) students. Continued surveillance of circulating viruses is needed to prevent virus infection outbreaks in congregate communities.
Asunto(s)
Infecciones por Adenoviridae , Humanos , South Carolina/epidemiología , Universidades , Brotes de Enfermedades , EstudiantesRESUMEN
PURPOSE: To develop a highly accelerated multi-echo spin-echo method, TEMPURA, for reducing the acquisition time and/or increasing spatial resolution for kidney T2 mapping. METHODS: TEMPURA merges several adjacent echoes into one k-space by either combining independent echoes or sharing one echo between k-spaces. The combined k-space is reconstructed based on compressed sensing theory. Reduced flip angles are used for the refocusing pulses, and the extended phase graph algorithm is used to correct the effects of indirect echoes. Two sequences were developed: a fast breath-hold sequence; and a high-resolution sequence. The performance was evaluated prospectively on a phantom, 16 healthy subjects, and two patients with different types of renal tumors. RESULTS: The fast TEMPURA method reduced the acquisition time from 3-5 min to one breath-hold (18 s). Phantom measurements showed that fast TEMPURA had a mean absolute percentage error (MAPE) of 8.2%, which was comparable to a standardized respiratory-triggered sequence (7.4%), but much lower than a sequence accelerated by purely k-t undersampling (21.8%). High-resolution TEMPURA reduced the in-plane voxel size from 3 × 3 to 1 × 1 mm2, resulting in improved visualization of the detailed anatomical structure. In vivo T2 measurements demonstrated good agreement (fast: MAPE = 1.3%-2.5%; high-resolution: MAPE = 2.8%-3.3%) and high correlation coefficients (fast: R = 0.85-0.98; high-resolution: 0.82-0.96) with the standardized method, outperforming k-t undersampling alone (MAPE = 3.3-4.5%, R = 0.57-0.59). CONCLUSION: TEMPURA provides fast and high-resolution renal T2 measurements. It has the potential to improve clinical throughput and delineate intratumoral heterogeneity and tissue habitats at unprecedented spatial resolution.
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Algoritmos , Neoplasias Renales , Riñón , Fantasmas de Imagen , Humanos , Neoplasias Renales/diagnóstico por imagen , Riñón/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Femenino , Adulto , Masculino , Interpretación de Imagen Asistida por Computador/métodos , Reproducibilidad de los Resultados , Persona de Mediana Edad , Aumento de la Imagen/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Contencion de la RespiraciónRESUMEN
Diffuse large B-cell lymphoma (DLBCL) is the most common malignancy that develops in patients with ataxia-telangiectasia, a cancer-predisposing inherited syndrome characterized by inactivating germline ATM mutations. ATM is also frequently mutated in sporadic DLBCL. To investigate lymphomagenic mechanisms and lymphoma-specific dependencies underlying defective ATM, we applied ribonucleic acid (RNA)-seq and genome-scale loss-offunction clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 screens to systematically interrogate B-cell lymphomas arising in a novel murine model (Atm-/-nu-/-) with constitutional Atm loss, thymic aplasia but residual T-cell populations. Atm-/-nu-/-lymphomas, which phenotypically resemble either activated B-cell-like or germinal center Bcell-like DLBCL, harbor a complex karyotype, and are characterized by MYC pathway activation. In Atm-/-nu-/-lymphomas, we discovered nucleotide biosynthesis as a MYCdependent cellular vulnerability that can be targeted through the synergistic nucleotidedepleting actions of mycophenolate mofetil (MMF) and the WEE1 inhibitor, adavosertib (AZD1775). The latter is mediated through a synthetically lethal interaction between RRM2 suppression and MYC dysregulation that results in replication stress overload in Atm-/-nu-/-lymphoma cells. Validation in cell line models of human DLBCL confirmed the broad applicability of nucleotide depletion as a therapeutic strategy for MYC-driven DLBCL independent of ATM mutation status. Our findings extend current understanding of lymphomagenic mechanisms underpinning ATM loss and highlight nucleotide metabolism as a targetable therapeutic vulnerability in MYC-driven DLBCL.
RESUMEN
OBJECTIVES: To understand the facilitators and barriers to the implementation of renal tumour biopsy (RTB) in the diagnostic pathway for renal tumours in England. PATIENTS AND METHODS: Participants consisted of patients who had a renal tumour diagnosed and/or treated at one of five tertiary centres in England, healthcare professionals involved in the direct care of patients diagnosed with renal tumours, and clinical service managers and commissioners. The study employed a mixed-methods research methodology consisting of individual interviews and an on-line survey that explored the types of facilitators and barriers individuals perceived and experienced and the frequency in which these were reported. A public dissemination event took place following the completion of data collection; to facilitate discussion of potential solutions to implementing RTB. RESULTS: There were 50 participant interviews (23 patients, 22 clinicians, and five health service commissioners/operations managers). The patient on-line survey received 52 responses, and the clinician survey received 22 responses. Patients most frequently reported influences in choosing whether to undergo RTB pertained to wanting to know the diagnosis of their kidney mass (40%), the advice or information provided by healthcare professionals (40%), and not wishing to delay treatment (23%). Clinicians most frequently reported barriers to recommending RTB related to their uncertainty of diagnostic accuracy (56%), availability of appointments or hospital beds (52%), concerns of risk of bleeding (44%), risk of seeding (41%), and delays in meeting national cancer pathway targets (41%). The dissemination event was attended by 18 participants (seven patients and 11 clinicians). Suggestions to improve implementation included reducing variation and promotion of standardisation of practice by a consensus statement, increasing the evidence base (clinicians) and improved communication by developing better patient aids such as videos and diagrams (patients and clinicians). CONCLUSION: Implementation of RTB may be dependent on the quality of information provided, its format and perceived reliability of the information. Increased utilisation of RTB may be improved by development of a consensus statement on the role of biopsy, with patients expressing a preference for alternative information aids such as patient videos.
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OBJECTIVES: To evaluate psychological, social, and financial outcomes amongst individuals undergoing a non-contrast abdominal computed tomography (CT) scan to screen for kidney cancer and other abdominal malignancies alongside the thoracic CT within lung cancer screening. SUBJECTS AND METHODS: The Yorkshire Kidney Screening Trial (YKST) is a feasibility study of adding a non-contrast abdominal CT scan to the thoracic CT within lung cancer screening. A total of 500 participants within the YKST, comprising all who had an abnormal CT scan and a random sample of one-third of those with a normal scan between 14/03/2022 and 24/08/2022 were sent a questionnaire at 3 and 6 months. Outcomes included the Psychological Consequences Questionnaire (PCQ), the short-form of the Spielberger State-Trait Anxiety Inventory, and the EuroQoL five Dimensions five Levels scale (EQ-5D-5L). Data were analysed using regression adjusting for participant age, sex, socioeconomic status, education, baseline quality of life (EQ-5D-5L), and ethnicity. RESULTS: A total of 380 (76%) participants returned questionnaires at 3 months and 328 (66%) at 6 months. There was no difference in any outcomes between participants with a normal scan and those with abnormal scans requiring no further action. Individuals requiring initial further investigations or referral had higher scores on the negative PCQ than those with normal scans at 3 months (standardised mean difference 0.28 sd, 95% confidence interval 0.01-0.54; P = 0.044). The difference was greater in those with anxiety or depression at baseline. No differences were seen at 6 months. CONCLUSION: Screening for kidney cancer and other abdominal malignancies using abdominal CT alongside the thoracic CT within lung cancer screening is unlikely to cause significant lasting psychosocial or financial harm to participants with incidental findings.
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Detección Precoz del Cáncer , Neoplasias Pulmonares , Tomografía Computarizada por Rayos X , Humanos , Masculino , Femenino , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/psicología , Persona de Mediana Edad , Anciano , Detección Precoz del Cáncer/psicología , Estudios de Factibilidad , Calidad de Vida , Encuestas y Cuestionarios , Radiografía Torácica , Radiografía Abdominal , Ansiedad , Neoplasias Renales/diagnóstico por imagen , Neoplasias Renales/psicologíaRESUMEN
The biological response to DNA double-strand breaks acts to preserve genome integrity. Individuals bearing inactivating mutations in components of this response exhibit clinical symptoms that include cellular radiosensitivity, immunodeficiency, and cancer predisposition. The archetype for such disorders is Ataxia-Telangiectasia caused by biallelic mutation in ATM, a central component of the DNA damage response. Here, we report that the ubiquitin ligase RNF168 is mutated in the RIDDLE syndrome, a recently discovered immunodeficiency and radiosensitivity disorder. We show that RNF168 is recruited to sites of DNA damage by binding to ubiquitylated histone H2A. RNF168 acts with UBC13 to amplify the RNF8-dependent histone ubiquitylation by targeting H2A-type histones and by promoting the formation of lysine 63-linked ubiquitin conjugates. These RNF168-dependent chromatin modifications orchestrate the accumulation of 53BP1 and BRCA1 to DNA lesions, and their loss is the likely cause of the cellular and developmental phenotypes associated with RIDDLE syndrome.
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Daño del ADN , Síndromes de Inmunodeficiencia/metabolismo , Transducción de Señal , Ubiquitina/metabolismo , Línea Celular , Histonas/metabolismo , Humanos , Síndromes de Inmunodeficiencia/genética , Tolerancia a Radiación , Enzimas Ubiquitina-Conjugadoras/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismoRESUMEN
The ATRX ATP-dependent chromatin remodelling/helicase protein associates with the DAXX histone chaperone to deposit histone H3.3 over repetitive DNA regions. Because ATRX-protein interactions impart functions, such as histone deposition, we used proximity-dependent biotinylation (BioID) to identify proximal associations for ATRX. The proteomic screen captured known interactors, such as DAXX, NBS1, and PML, but also identified a range of new associating proteins. To gauge the scope of their roles, we examined three novel ATRX-associating proteins that likely differed in function, and for which little data were available. We found CCDC71 to associate with ATRX, but also HP1 and NAP1, suggesting a role in chromatin maintenance. Contrastingly, FAM207A associated with proteins involved in ribosome biosynthesis and localized to the nucleolus. ATRX proximal associations with the SLF2 DNA damage response factor help inhibit telomere exchanges. We further screened for the proteomic changes at telomeres when ATRX, SLF2, or both proteins were deleted. The loss caused important changes in the abundance of chromatin remodelling, DNA replication, and DNA repair factors at telomeres. Interestingly, several of these have previously been implicated in alternative lengthening of telomeres. Altogether, this study expands the repertoire of ATRX-associating proteins and functions.
Asunto(s)
Proteínas Co-Represoras/genética , Proteínas de Unión al ADN/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Proteínas Nucleares/genética , Proteína Nuclear Ligada al Cromosoma X/genética , Biotinilación/genética , Proteínas de Ciclo Celular/genética , Línea Celular , Cromatina/genética , Homólogo de la Proteína Chromobox 5/genética , Daño del ADN/genética , Reparación del ADN/genética , Chaperonas de Histonas/genética , Histonas/genética , Humanos , Chaperonas Moleculares/genética , Proteína de la Leucemia Promielocítica/genética , Telómero/genética , ARNt MetiltransferasasRESUMEN
Earlier detection and screening for kidney cancer has been identified as a key research priority, however the low prevalence of the disease in unselected populations limits the cost-effectiveness of screening. Risk-stratified screening for kidney cancer may improve early detection by targeting high-risk individuals whilst limiting harms in low-risk individuals, potentially increasing the cost-effectiveness of screening. A number of models have been identified which estimate kidney cancer risk based on both phenotypic and genetic data, and while several of the former have been shown to identify individuals at high-risk of developing kidney cancer with reasonable accuracy, current evidence does not support including a genetic component. Combined screening for lung cancer and kidney cancer has been proposed, as the two malignancies share some common risk factors. A modelling study estimated that using lung cancer risk models (currently used for risk-stratified lung cancer screening) could capture 25% of patients with kidney cancer, which is only slightly lower than using the best performing kidney cancer-specific risk models based on phenotypic data (27%-33%). Additionally, risk-stratified screening for kidney cancer has been shown to be acceptable to the public. The following review summarises existing evidence regarding risk-stratified screening for kidney cancer, highlighting the risks and benefits, as well as exploring the management of potential harms and further research needs.