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Cancers from sun-exposed skin accumulate "driver" mutations, causally implicated in oncogenesis. Because errors incorporated during translesion synthesis (TLS) opposite UV lesions would generate these mutations, TLS mechanisms are presumed to underlie cancer development. To address the role of TLS in skin cancer formation, we determined which DNA polymerase is responsible for generating UV mutations, analyzed the relative contributions of error-free TLS by Polη and error-prone TLS by Polθ to the replication of UV-damaged DNA and to genome stability, and examined the incidence of UV-induced skin cancers in Polθ-/-, Polη-/-, and Polθ-/- Polη-/- mice. Our findings that the incidence of skin cancers rises in Polθ-/- mice and is further exacerbated in Polθ-/- Polη-/- mice compared with Polη-/- mice support the conclusion that error-prone TLS by Polθ provides a safeguard against tumorigenesis and suggest that cancer formation can ensue in the absence of somatic point mutations.
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DNA Polimerase Dirigida por DNA/metabolismo , DNA Polimerase Dirigida por DNA/fisiologia , Neoplasias Cutâneas/metabolismo , Animais , Dano ao DNA/genética , Reparo do DNA/genética , Replicação do DNA/fisiologia , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Instabilidade Genômica/genética , Humanos , Camundongos , Camundongos Knockout , Mutação/genética , Pele/citologia , Pele/metabolismo , Neoplasias Cutâneas/genética , Raios Ultravioleta/efeitos adversos , DNA Polimerase tetaRESUMO
Purified translesion synthesis (TLS) DNA polymerases (Pols) replicate through DNA lesions with a low fidelity; however, TLS operates in a predominantly error-free manner in normal human cells. To explain this incongruity, here we determine whether Y family Pols, which play an eminent role in replication through a diversity of DNA lesions, are incorporated into a multiprotein ensemble and whether the intrinsically high error rate of the TLS Pol is ameliorated by the components in the ensemble. To this end, we provide evidence for an indispensable role of Werner syndrome protein (WRN) and WRN-interacting protein 1 (WRNIP1) in Rev1-dependent TLS by Y family Polη, Polι, or Polκ and show that WRN, WRNIP1, and Rev1 assemble together with Y family Pols in response to DNA damage. Importantly, we identify a crucial role of WRN's 3' â 5' exonuclease activity in imparting high fidelity on TLS by Y family Pols in human cells, as the Y family Pols that accomplish TLS in an error-free manner manifest high mutagenicity in the absence of WRN's exonuclease function. Thus, by enforcing high fidelity on TLS Pols, TLS mechanisms have been adapted to safeguard against genome instability and tumorigenesis.
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DNA Polimerase Dirigida por DNA , Síntese de DNA Translesão , Helicase da Síndrome de Werner , Humanos , Dano ao DNA , Reparo do DNA , Replicação do DNA , DNA Polimerase Dirigida por DNA/metabolismo , Exonucleases/metabolismo , Síntese de DNA Translesão/genética , Helicase da Síndrome de Werner/genética , Helicase da Síndrome de Werner/metabolismoRESUMO
Lesions on DNA uncouple DNA synthesis from the replisome, generating stretches of unreplicated single-stranded DNA (ssDNA) behind the replication fork. These ssDNA gaps need to be filled in to complete DNA duplication. Gap-filling synthesis involves either translesion DNA synthesis (TLS) or template switching (TS). Controlling these processes, ubiquitylated PCNA recruits many proteins that dictate pathway choice, but the enzymes regulating PCNA ubiquitylation in vertebrates remain poorly defined. Here we report that the E3 ubiquitin ligase RFWD3 promotes ubiquitylation of proteins on ssDNA. The absence of RFWD3 leads to a profound defect in recruitment of key repair and signaling factors to damaged chromatin. As a result, PCNA ubiquitylation is inhibited without RFWD3, and TLS across different DNA lesions is drastically impaired. We propose that RFWD3 is an essential coordinator of the response to ssDNA gaps, where it promotes ubiquitylation to drive recruitment of effectors of PCNA ubiquitylation and DNA damage bypass.
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Cromatina/metabolismo , Quebras de DNA de Cadeia Simples , Reparo do DNA , Replicação do DNA , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Linhagem Celular Tumoral , Cromatina/genética , DNA Polimerase Dirigida por DNA/metabolismo , Feminino , Humanos , Antígeno Nuclear de Célula em Proliferação/genética , Especificidade por Substrato , Ubiquitina-Proteína Ligases/genética , Ubiquitinação , Xenopus laevisRESUMO
Skip lesions are an enigmatic spatial feature characterizing Crohn's disease (CD). They comprise inflamed and adjacent non-inflamed tissue sections with a clear demarcation. Currently, spatial features of the human gastrointestinal (GI) system lack clarity regarding the organization of microbes, mucus, tissue, and host cells during inflammation. New technologies with multiplexing abilities and innovative approaches provide ways of examining the spatial organization of inflamed and non-inflamed tissues in CD, which may open new avenues for diagnosis, prognosis, and treatment. In this review, we present evidence of the relevance of spatial context in patients with CD and the methods and ideas recently published in studies of spatiality during inflammation. With this review, we aim to provide inspiration for further research to address existing gaps.
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Doença de Crohn , Doença de Crohn/imunologia , Doença de Crohn/patologia , Humanos , Animais , Inflamação/imunologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Trato Gastrointestinal/imunologia , Trato Gastrointestinal/patologiaRESUMO
Religious fundamentalism, characterized by rigid adherence to a set of beliefs putatively revealing inerrant truths, is ubiquitous across cultures and has a global impact on society. Understanding the psychological and neurobiological processes producing religious fundamentalism may inform a variety of scientific, sociological, and cultural questions. Research indicates that brain damage can alter religious fundamentalism. However, the precise brain regions involved with these changes remain unknown. Here, we analyzed brain lesions associated with varying levels of religious fundamentalism in two large datasets from independent laboratories. Lesions associated with greater fundamentalism were connected to a specific brain network with nodes in the right orbitofrontal, dorsolateral prefrontal, and inferior parietal lobe. This fundamentalism network was strongly right hemisphere lateralized and highly reproducible across the independent datasets (r = 0.82) with cross-validations between datasets. To explore the relationship of this network to lesions previously studied by our group, we tested for similarities to twenty-one lesion-associated conditions. Lesions associated with confabulation and criminal behavior showed a similar connectivity pattern as lesions associated with greater fundamentalism. Moreover, lesions associated with poststroke pain showed a similar connectivity pattern as lesions associated with lower fundamentalism. These findings are consistent with the current understanding of hemispheric specializations for reasoning and lend insight into previously observed epidemiological associations with fundamentalism, such as cognitive rigidity and outgroup hostility.
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Rede Nervosa , Humanos , Masculino , Feminino , Rede Nervosa/fisiopatologia , Rede Nervosa/patologia , Pessoa de Meia-Idade , Encéfalo/fisiopatologia , Encéfalo/patologia , Adulto , Religião , Imageamento por Ressonância Magnética , Lesões Encefálicas/patologia , Lesões Encefálicas/fisiopatologia , IdosoRESUMO
UV-induced photoproducts are responsible for the pathological effects of sunlight. Mutations in nucleotide excision repair (NER) cause severe pathologies characterized by sunlight sensitivity, coupled to elevated predisposition to cancer and/or neurological dysfunctions. We have previously shown that in UV-irradiated non-cycling cells, only a particular subset of lesions activates the DNA damage response (DDR), and this requires NER and EXO1 activities. To define the molecular mechanism acting at these lesions, we demonstrate that Y family TLS polymerases are recruited at NER- and EXO1-positive lesion sites in non-S phase cells. The coordinated action of EXO1 and Y family TLS polymerases promotes checkpoint activation, leads to lesion repair, and is crucial to prevent cytotoxic double-strand break (DSB) formation.
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Pontos de Checagem do Ciclo Celular/efeitos da radiação , Quebras de DNA de Cadeia Dupla , Enzimas Reparadoras do DNA/metabolismo , Reparo do DNA/efeitos da radiação , DNA Polimerase Dirigida por DNA/metabolismo , Exodesoxirribonucleases/metabolismo , Raios Ultravioleta/efeitos adversos , Morte Celular/efeitos da radiação , Linhagem Celular , Enzimas Reparadoras do DNA/genética , DNA Polimerase Dirigida por DNA/genética , Exodesoxirribonucleases/genética , Humanos , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Nucleotidiltransferases/genética , Nucleotidiltransferases/metabolismo , Transporte Proteico , DNA Polimerase iotaRESUMO
BACKGROUND & AIMS: Pancreatic ductal adenocarcinoma (PDAC) is characterized by desmoplastic stroma surrounding most tumors. Activated stromal fibroblasts, namely cancer-associated fibroblasts (CAFs), play a major role in PDAC progression. We analyzed whether CAFs influence acinar cells and impact PDAC initiation, that is, acinar-to-ductal metaplasia (ADM). ADM connection with PDAC pathophysiology is indicated, but not yet established. We hypothesized that CAF secretome might play a significant role in ADM in PDAC initiation. METHODS: Mouse and human acinar cell organoids, acinar cells cocultured with CAFs and exposed to CAF-conditioned media, acinar cell explants, and CAF cocultures were examined by means of quantitative reverse transcription polymerase chain reaction, RNA sequencing, immunoblotting, and confocal microscopy. Data from liquid chromatography with tandem mass spectrometry analysis of CAF-conditioned medium and RNA sequencing data of acinar cells post-conditioned medium exposure were integrated using bioinformatics tools to identify the molecular mechanism for CAF-induced ADM. Using confocal microscopy, immunoblotting, and quantitative reverse transcription polymerase chain reaction analysis, we validated the depletion of a key signaling axis in the cell line, acinar explant coculture, and mouse cancer-associated fibroblasts (mCAFs). RESULTS: A close association of acino-ductal markers (Ulex europaeus agglutinin 1, amylase, cytokeratin-19) and mCAFs (α-smooth muscle actin) in LSL-KrasG12D/+; LSL-Trp53R172H/+; Pdx1Cre (KPC) and LSL-KrasG12D/+; Pdx1Cre (KC) autochthonous progression tumor tissue was observed. Caerulein treatment-induced mCAFs increased cytokeratin-19 and decreased amylase in wild-type and KC pancreas. Likewise, acinar-mCAF cocultures revealed the induction of ductal transdifferentiation in cell line, acinar-organoid, and explant coculture formats in WT and KC mice pancreas. Proteomic and transcriptomic data integration revealed a novel laminin α5/integrinα4/stat3 axis responsible for CAF-mediated acinar-to-ductal cell transdifferentiation. CONCLUSIONS: Results collectively suggest the first evidence for CAF-influenced acino-ductal phenotypic switchover, thus highlighting the tumor microenvironment role in pancreatic carcinogenesis inception.
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Células Acinares , Fibroblastos Associados a Câncer , Carcinoma Ductal Pancreático , Transdiferenciação Celular , Laminina , Neoplasias Pancreáticas , Animais , Humanos , Camundongos , Células Acinares/metabolismo , Células Acinares/patologia , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/genética , Linhagem Celular Tumoral , Técnicas de Cocultura , Meios de Cultivo Condicionados/metabolismo , Metaplasia/patologia , Metaplasia/metabolismo , Organoides/metabolismo , Organoides/patologia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/genética , Transdução de Sinais , Microambiente TumoralRESUMO
DESCRIPTION: Subepithelial lesions of the gastrointestinal tract are not encountered uncommonly during routine endoscopy. There has been remarkable progress in the development of endoscopic options for the resection of subepithelial lesions, including full-thickness resection. The purpose of this American Gastroenterological Association (AGA) Clinical Practice Update (CPU) is to describe the various techniques for endoscopic full-thickness resection and to facilitate their appropriate application in the management of subepithelial lesions. METHODS: This CPU was commissioned and approved by the AGA Institute Clinical Practice Updates Committee (CPUC) and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership and underwent internal peer review by the CPUC and external peer review through standard procedures of Gastroenterology.
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Ressecção Endoscópica de Mucosa , Gastroenterologia , Humanos , Trato Gastrointestinal/cirurgia , Ressecção Endoscópica de Mucosa/efeitos adversos , Ressecção Endoscópica de Mucosa/métodos , Endoscopia Gastrointestinal/efeitos adversos , Endoscopia Gastrointestinal/métodosRESUMO
The CCL2-CCR2 axis is involved in lupus nephritis, however the precise roles in the mechanisms by which different pathological lesions develop after glomerular immune complex deposition remain elusive. Previously, we demonstrated that genetic CCR2 inhibition induced a histological switch from glomerular endocapillary hypercellularity to wire-loop lesions in murine lupus nephritis. This study aimed to clarify the CCL2-CCR2 axis-mediated cellular mechanism in the formation of these different pathological lesions. We injected MRL/lpr mouse-derived monoclonal IgG3 antibody-producing hybridomas, 2B11.3 or B1, into wild-type (WT) mice to selectively induce glomerular endocapillary hypercellularity or wire-loop lesions. The expression of chemokine and chemokine receptors was analyzed using RT-quantitative PCR and/or immunofluorescence. We found 2B11.3 caused glomerular endocapillary hypercellularity in WT mice with glomerular infiltration of larger numbers of CCR2-expressing macrophages and neutrophils phagocyting immune complex, whereas B1 induced wire-loop lesions. In glomerular endocapillary hypercellularity, CCL2 was identified as the ligand involved in the CCR2-positive cell infiltration; it was expressed by glomerular endothelial cells and macrophages. Notably, 2B11.3-induced glomerular endocapillary hypercellularity converted to wire-loop lesions with reduced glomerular macrophage and neutrophil infiltration in CCL2-deficient (Ccl2-/-) mice similarly observed in Ccr2-/- mice. Moreover, this histological conversion was also observed when both glomerular macrophage and neutrophil infiltration were inhibited in anti-Ly6G antibody-treated Ccr5-/- mice but not when only glomerular macrophage infiltration was inhibited in Ccr5-/- mice or when only glomerular neutrophil infiltration was inhibited in anti-Ly6G antibody-treated WT mice. In contrast, B1 injection caused wire-loop lesions in Ccl2-/- and Ccr2-/- mice, as observed in WT mice. Moreover, 2B11.3 induced CCL2 from glomerular endothelial cells to a larger extent than B1 when injected into Ccr2-/- mice. In conclusion, the CCL2-CCR2 axis determines whether glomerular endocapillary hypercellularity or wire-loop lesions develop by regulating glomerular infiltration of phagocytic cells: macrophages and neutrophils. © 2024 The Pathological Society of Great Britain and Ireland.
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Quimiocina CCL2 , Glomérulos Renais , Nefrite Lúpica , Macrófagos , Receptores CCR2 , Animais , Nefrite Lúpica/patologia , Nefrite Lúpica/imunologia , Nefrite Lúpica/metabolismo , Quimiocina CCL2/metabolismo , Receptores CCR2/metabolismo , Receptores CCR2/genética , Glomérulos Renais/patologia , Glomérulos Renais/metabolismo , Glomérulos Renais/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/patologia , Infiltração de Neutrófilos , Camundongos Endogâmicos MRL lpr , Neutrófilos/imunologia , Neutrófilos/metabolismo , Neutrófilos/patologia , Feminino , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL , Transdução de SinaisRESUMO
The E3 ubiquitin ligase thyroid hormone receptor interacting protein 12 (TRIP12) has been implicated in pancreatic adenocarcinoma (PDAC) through its role in mediating the degradation of pancreas transcription factor 1a (PTF1a). PTF1a is a transcription factor essential for the acinar differentiation state that is notably diminished during the early steps of pancreatic carcinogenesis. Despite these findings, the direct involvement of TRIP12 in the onset of pancreatic cancer has yet to be established. In this study, we demonstrated that TRIP12 protein was significantly upregulated in human pancreatic preneoplastic lesions. Furthermore, we observed that TRIP12 overexpression varied within PDAC samples and PDAC-derived cell lines. We further demonstrated that TRIP12 was required for PDAC-derived cell growth and for the expression of E2F-targeted genes. Acinar-to-ductal cell metaplasia (ADM) is a reversible process that reflects the high plasticity of acinar cells. ADM becomes irreversible in the presence of oncogenic Kras mutations and leads to the formation of preneoplastic lesions. Using two genetically modified mouse models, we showed that a loss of TRIP12 prevented acini from developing ADM in response to pancreatic injury. With two additional mouse models, we further discovered that a depletion of TRIP12 prevented the formation of KrasG12D-induced preneoplastic lesions and impaired metastasis formation in the presence of mutated KrasG12D and Trp53R172H genes. In summary our study identified an overexpression of TRIP12 from the early stages of pancreatic carcinogenesis and proposed this E3 ubiquitin ligase as a novel regulator of acinar plasticity with an important dual role in initiation and metastatic steps of PDAC. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.
Assuntos
Células Acinares , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Ubiquitina-Proteína Ligases , Animais , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/enzimologia , Humanos , Células Acinares/patologia , Células Acinares/metabolismo , Células Acinares/enzimologia , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/enzimologia , Metaplasia/patologia , Metaplasia/metabolismo , Plasticidade Celular , Carcinogênese/genética , Carcinogênese/metabolismo , Camundongos , Linhagem Celular Tumoral , Proliferação de Células , Camundongos Knockout , Regulação Neoplásica da Expressão Gênica , Lesões Pré-Cancerosas/patologia , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/metabolismo , Lesões Pré-Cancerosas/enzimologia , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Transformação Celular Neoplásica/metabolismo , Proteínas de TransporteRESUMO
Chronic active lesions (CAL) are an important manifestation of chronic inflammation in multiple sclerosis and have implications for non-relapsing biological progression. In recent years, the discovery of innovative MRI and PET-derived biomarkers has made it possible to detect CAL, and to some extent quantify them, in the brain of persons with multiple sclerosis, in vivo. Paramagnetic rim lesions on susceptibility-sensitive MRI sequences, MRI-defined slowly expanding lesions on T1-weighted and T2-weighted scans, and 18-kDa translocator protein-positive lesions on PET are promising candidate biomarkers of CAL. While partially overlapping, these biomarkers do not have equivalent sensitivity and specificity to histopathological CAL. Standardization in the use of available imaging measures for CAL identification, quantification and monitoring is lacking. To fast-forward clinical translation of CAL, the North American Imaging in Multiple Sclerosis Cooperative developed a consensus statement, which provides guidance for the radiological definition and measurement of CAL. The proposed manuscript presents this consensus statement, summarizes the multistep process leading to it, and identifies the remaining major gaps in knowledge.
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Consenso , Imageamento por Ressonância Magnética , Esclerose Múltipla , Humanos , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/patologia , Imageamento por Ressonância Magnética/normas , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Neuroimagem/normas , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Tomografia por Emissão de Pósitrons/normas , Tomografia por Emissão de Pósitrons/métodosRESUMO
Focal cortical dysplasias are abnormalities of the cerebral cortex associated with an elevated risk of neurological disturbances. Cortical spreading depolarization/depression is a correlate of migraine aura/headache and a trigger of migraine pain mechanisms. However, cortical spreading depolarization/depression is associated with cortical structural changes, which can be classified as transient focal cortical dysplasias. Migraine is reported to be associated with changes in various brain structures, including malformations and lesions in the cortex. Such malformations may be related to focal cortical dysplasias, which may play a role in migraine pathogenesis. Results obtained so far suggest that focal cortical dysplasias may belong to the causes and consequences of migraine. Certain focal cortical dysplasias may lower the threshold of cortical excitability and facilitate the action of migraine triggers. Migraine prevalence in epileptic patients is higher than in the general population, and focal cortical dysplasias are an established element of epilepsy pathogenesis. In this narrative/hypothesis review, we present mainly information on cortical structural changes in migraine, but studies on structural alterations in deep white matter and other brain regions are also presented. We develop the hypothesis that focal cortical dysplasias may be causally associated with migraine and link pathogeneses of migraine and epilepsy.
Assuntos
Epilepsia , Displasia Cortical Focal , Transtornos de Enxaqueca , Humanos , Transtornos de Enxaqueca/etiologia , Encéfalo , Córtex Cerebral , Epilepsia/etiologiaRESUMO
BACKGROUND: Bats are recognized as the natural reservoir of several zoonotic viruses that pose a threat to public health worldwide. In our recent reports we describe the identification of a novel poxvirus, IsrRAPXV, in Egyptian fruit bats. This poxvirus is associated with high morbidity and mortality in bats. METHODS: Herein, we describe the identification of poxvirus in a female patient hospitalized with systemic symptoms and severe painful skin lesions on her hands. We performed qPCR, whole genome sequencing and phylogenetic analysis to identify and characterize this poxvirus as the etiologic agent. RESULTS: The patient interacted with wounded and sick bats as a volunteer in a bat shelter run by the Israel bat sanctuary organization. Samples collected from the patient's skin lesions were positive for the presence of IsrRAPXV by PCR. Additionally, phylogenetic analysis showed that this virus is identical to IsrRAPXV originally described by us as the causative agent of skin lesions in fruit bats. CONCLUSIONS: Our finding suggest that IsrRAPXV is zoonotic and therefore veterinarians and volunteers working in bats shelter should meticulously follow the guidelines of working with bats and use required personal protective equipment.
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In Norway, single cohort vaccination with quadrivalent HPV (qHPV) vaccine targeting 12-year-old girls took place from 2009-2016. In 2020, the oldest vaccinated cohort was 23 years old and had approached the age where risk of being diagnosed with cervical intraepithelial lesion grade 2 or worse (CIN2+) increases rapidly. The aim of this cohort study was to assess direct qHPV vaccine effectiveness (VE) against CIN2+ among Norwegian women aged 16-30 in 2007-2020. By using population-based health registries and individual-level data on vaccination status and potential subsequent CIN2+ incidence, we found 82% qHPV VE among women vaccinated before the age of 17.
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Healthy livers contain 80% of body resident macrophages known as Kupffer cells. In diseased livers, the number of Kupffer cells usually drops but is compensated by infiltration of monocyte-derived macrophages, some of which can differentiate into Kupffer-like cells. Early studies suggest that Kupffer cells play important roles in both promoting liver injury and liver regeneration. Yet, the distinction between the functionalities of resident and infiltrating macrophages is not always made. By using more specific macrophage markers and targeted cell depletion and single-cell RNA sequencing, recent studies revealed several subsets of monocyte-derived macrophages that play important functions in inducing liver damage and inflammation as well as in liver repair and regeneration. In this review, we discuss the different roles that hepatic macrophages play in promoting necrotic liver lesion resolution and dead cell clearance, as well as the targeting of these cells as potential tools for the development of novel therapies for acute liver failure and acute-on-chronic liver failure.
Assuntos
Células de Kupffer , Regeneração Hepática , Fígado , Necrose , Humanos , Animais , Fígado/patologia , Fígado/metabolismo , Células de Kupffer/metabolismo , Células de Kupffer/patologia , Macrófagos/metabolismo , Macrófagos/patologia , Macrófagos/imunologiaRESUMO
Our previous study reckons that the impact of the rs1801133 variant of 5,10-methylenetetrahydrofolate reductase (MTHFR) on coronary artery disease (CAD) is possibly mediated by cardiometabolic disorder. This study is performed to verify this hypothesis. Four hundred and thirty CAD patients and 216 CAD-free individuals were enrolled in this case-control study. The rs1801133 variant was genotyped by PCR-RFLP. Severity of coronary lesions was evaluated by number of stenotic coronary vessels and extent of coronary stenosis. The rs1801133 T allele significantly increased homocysteine levels in patients with CAD and CAD-free individuals. Individuals with the T allele of rs1801133 had an increased risk of developing CAD. In contrast, individuals with the TT genotype of rs1801133 were at high risk of multiple vessel lesions. The carriers of CT genotype had higher levels of systolic blood pressure (SBP), low-density lipoprotein cholesterol (LDL-C), and high-sensitivity C-reactive protein (hs-CRP), and lower levels of apolipoprotein A1 (APOA1) than those with CC genotype in male patients with CAD. The receiver operating characteristic (ROC) curve and precision-recall (PR) curve indicated that hyperhomocysteinemia was sensitive to predict the severity of CAD. Multivariate logistic regression revealed that homocysteine, rs1801133, age, smoking, weight, body mass index (BMI), lipoprotein(a) [Lp(a)], and hs-CRP were independent risk factors for CAD. The increased risk of CAD and severity of coronary lesions associated with rs1801133 in the Chinese Han population were attributed, at least partly, to high homocysteine levels. Hyperhomocysteinemia had a high predictive value for severe CAD or multiple vessel lesions.
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Doença da Artéria Coronariana , Homocisteína , Metilenotetra-Hidrofolato Redutase (NADPH2) , Polimorfismo de Nucleotídeo Único , Humanos , Homocisteína/sangue , Masculino , Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/patologia , Pessoa de Meia-Idade , Feminino , Estudos de Casos e Controles , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Índice de Gravidade de Doença , Idoso , Fatores de Risco , Predisposição Genética para Doença , Curva ROC , Genótipo , Proteína C-Reativa/metabolismo , Proteína C-Reativa/genética , Alelos , Apolipoproteína A-I/genética , Apolipoproteína A-I/sangueRESUMO
Attaching/effacing (A/E) pathogens induce DNA damage and colorectal cancer by injecting effector proteins into host cells via the type III secretion system (T3SS). EspF is one of the T3SS-dependent effector proteins exclusive to A/E pathogens, which include enterohemorrhagic Escherichia coli. The role of EspF in the induction of double-strand breaks (DSBs) and the phosphorylation of the repair protein SMC1 has been demonstrated previously. However, the process of damage accumulation and DSB formation has remained enigmatic, and the damage response is not well understood. Here, we first showed a compensatory increase in the mismatch repair proteins MutS homolog 2 (MSH2) and MSH6, as well as poly(ADP-ribose) polymerase 1, followed by a dramatic decrease, threatening cell survival in the presence of EspF. Flow cytometry revealed that EspF arrested the cell cycle at the G2/M phase to facilitate DNA repair. Subsequently, 8-oxoguanine (8-oxoG) lesions, a marker of oxidative damage, were assayed by ELISA and immunofluorescence, which revealed the accumulation of 8-oxoG from the cytosol to the nucleus. Furthermore, the status of single-stranded DNA (ssDNA) and DSBs was confirmed. We observed that EspF accelerated the course of DNA lesions, including 8-oxoG and unrepaired ssDNA, which were converted into DSBs; this was accompanied by the phosphorylation of replication protein A 32 in repair-defective cells. Collectively, these findings reveal that EspF triggers various types of oxidative DNA lesions with impairment of the DNA damage response and may result in genomic instability and cell death, offering novel insight into the tumorigenic potential of EspF.IMPORTANCEOxidative DNA lesions play causative roles in colitis-associated colon cancer. Accumulating evidence shows strong links between attaching/effacing (A/E) pathogens and colorectal cancer (CRC). EspF is one of many effector proteins exclusive to A/E pathogens with defined roles in the induction of oxidative stress, double-strand breaks (DSBs), and repair dysregulation. Here, we found that EspF promotes reactive oxygen species generation and 8-oxoguanine (8-oxoG) lesions when the repair system is activated, contributing to sustained cell survival. However, infected cells exposed to EspF presented 8-oxoG, which results in DSBs and ssDNA accumulation when the cell cycle is arrested at the G2/M phase and the repair system is defective or saturated by DNA lesions. In addition, we found that EspF could intensify the accumulation of nuclear DNA lesions through oxidative and replication stress. Overall, our work highlights the involvement of EspF in DNA lesions and DNA damage response, providing a novel avenue by which A/E pathogens may contribute to CRC.
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Neoplasias Colorretais , Escherichia coli Êntero-Hemorrágica , Humanos , Células Epiteliais , Reparo do DNA , Dano ao DNA , Estresse OxidativoRESUMO
Tuberous sclerosis complex (TSC) is a rare autosomal dominant disorder caused by mutations in the TSC1 or TSC2 gene. The aim of this study was to analyze the genotypes and phenotypes of Korean patients diagnosed with TSC and expand our understanding of this disorder. This retrospective observational study included 331 patients clinically diagnosed with TSC between November 1990 and April 2023 at Severance Children's Hospital, Seoul, South Korea. The demographic and clinical characteristics of the patients were investigated. Thirty novel variants were identified. Of the 331 patients, 188 underwent genetic testing, and genotype-phenotype variation was analyzed according to the type of gene mutation and functional domain. Fourty-nine patients (49/188, 26%) were had TSC1 mutations, 103 (55%) had TSC2 mutations, and 36 (19%) had no mutation identified (NMI). Hotspots were identified in exons 8 of TSC1 and exons 35 and 41 of TSC2. Patients with TSC2 mutations exhibited a significantly younger age at the time of seizure onset and had refractory epilepsy. Infantile epileptic spasms syndrome (IESS) was more common in the middle mutation domain of TSC2 than in the hamartin domain. Additionally, retinal hamartoma, cardiac rhabdomyoma, and renal abnormalities were significantly associated with TSC2 compared with other gene types. This study contributes to our understanding of TSC by expanding the genotypic spectrum with novel variants and providing insights into the clinical spectrum of patients with TSC in Korea.
RESUMO
Several nomenclature and grading systems have been proposed for conjunctival melanocytic intraepithelial lesions (C-MIL). The fourth "WHO Classification of Eye Tumors" (WHO-EYE04) proposed a C-MIL classification, capturing the progression of noninvasive neoplastic melanocytes from low- to high-grade lesions, onto melanoma in situ (MIS), and then to invasive melanoma. This proposal was revised to the WHO-EYE05 C-MIL system, which simplified the high-grade C-MIL, whereby MIS was subsumed into high-grade C-MIL. Our aim was to validate the WHO-EYE05 C-MIL system using digitized images of C-MIL, stained with hematoxylin and eosin and immunohistochemistry. However, C-MIL cases were retrieved from 3 supraregional ocular pathology centers. Adequate conjunctival biopsies were stained with hematoxylin and eosin, Melan-A, SOX10, and PReferentially expressed Antigen in Melanoma. Digitized slides were uploaded on the SmartZoom platform and independently scored by 4 ocular pathologists to obtain a consensus score, before circulating to 14 expert eye pathologists for independent scoring. In total, 105 cases from 97 patients were evaluated. The initial consensus diagnoses using the WHO-EYE04 C-MIL system were as follows: 28 benign conjunctival melanoses, 13 low-grade C-MIL, 37 high-grade C-MIL, and 27 conjunctival MIS. Using this system resulted in 93% of the pathologists showing only fair-to-moderate agreement (kappa statistic) with the consensus score. The WHO-EYE05 C-MIL system (with high-grade C-MIL and MIS combined) improved consistency between pathologists, with the greatest level of agreement being seen with benign melanosis (74.5%) and high-grade C-MIL (85.4%). Lowest agreements remained between pathologists for low-grade C-MIL (38.7%). Regarding WHO-EYE05 C-MIL scoring and clinical outcomes, local recurrences of noninvasive lesions developed in 8% and 34% of the low- and high-grade cases. Invasive melanoma only occurred in 47% of the cases that were assessed as high-grade C-MIL. This extensive international collaborative study is the first to undertake a comprehensive review of the WHO-EYE05 C-MIL scoring system, which showed good interobserver agreement and reproducibility.
Assuntos
Melanoma , Melanose , Neoplasias Cutâneas , Humanos , Melanoma/diagnóstico , Melanoma/patologia , Prognóstico , Reprodutibilidade dos Testes , Amarelo de Eosina-(YS) , Hematoxilina , Melanócitos , Neoplasias Cutâneas/patologia , Melanose/patologia , Organização Mundial da Saúde , Estudos Multicêntricos como AssuntoRESUMO
Various histopathological, clinical and imaging parameters have been evaluated to identify a subset of women diagnosed with lesions with uncertain malignant potential (B3 or BIRADS 3/4A lesions) who could safely be observed rather than being treated with surgical excision, with little impact on clinical practice. The primary reason for surgery is to rule out an upgrade to either ductal carcinoma in situ or invasive breast cancer, which occurs in up to 30% of patients. We hypothesised that the stromal immune microenvironment could indicate the presence of carcinoma associated with a ductal B3 lesion and that this could be detected in biopsies by counting lymphocytes as a predictive biomarker for upgrade. A higher number of lymphocytes in the surrounding specialised stroma was observed in upgraded ductal and papillary B3 lesions than non-upgraded (p < 0.01, negative binomial model, n = 307). We developed a model using lymphocytes combined with age and the type of lesion, which was predictive of upgrade with an area under the curve of 0.82 [95% confidence interval 0.77-0.87]. The model can identify some patients at risk of upgrade with high sensitivity, but with limited specificity. Assessing the tumour microenvironment including stromal lymphocytes may contribute to reducing unnecessary surgeries in the clinic, but additional predictive features are needed.