DNA-binding
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Impaired fibroblast growth factor receptor (FGFR) signaling is associated with many human conditions, including growth disorders, degenerative diseases, and cancer. Current FGFR therapeutics are based on chemical inhibitors of FGFR tyrosine kinase activity (TKIs). However, FGFR TKIs are limited in their target specificity as they generally inhibit all FGFRs and other receptor tyrosine kinases. In the search for specific inhibitors of human FGFR1, we identified VZ23, a DNA aptamer that binds to FGFR1b and FGFR1c with a KD of 55 nM and 162 nM, respectively, but not to the other FGFR variants (FGFR2b, FGFR2c, FGFR3b, FGFR3c, FGFR4). In cells, VZ23 inhibited the activation of downstream FGFR1 signaling and FGFR1-mediated regulation of cellular senescence, proliferation, and extracellular matrix homeostasis. Consistent with the specificity toward FGFR1 observed in vitro, VZ23 did not inhibit FGFR2-4 signaling in cells. We show that the VZ23 inhibits FGFR1 signaling in the presence of cognate fibroblast growth factor (FGF) ligands and its inhibitory activity is linked to its capacity to form unusual G-quadruplex structure. Our data suggest that targeting FGFR1 with DNA aptamers could be an effective alternative to TKIs for treating impaired FGFR1 signaling in human craniosynostoses.
- Publikační typ
- časopisecké články MeSH
Heavy metals are naturally occurring components of the Earth's crust and persistent environmental pollutants. Human exposure to heavy metals occurs via various pathways, including inhalation of air/dust particles, ingesting contaminated water or soil, or through the food chain. Their bioaccumulation may lead to diverse toxic effects affecting different body tissues and organ systems. The toxicity of heavy metals depends on the properties of the given metal, dose, route, duration of exposure (acute or chronic), and extent of bioaccumulation. The detrimental impacts of heavy metals on human health are largely linked to their capacity to interfere with antioxidant defense mechanisms, primarily through their interaction with intracellular glutathione (GSH) or sulfhydryl groups (R-SH) of antioxidant enzymes such as superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx), glutathione reductase (GR), and other enzyme systems. Although arsenic (As) is believed to bind directly to critical thiols, alternative hydrogen peroxide production processes have also been postulated. Heavy metals are known to interfere with signaling pathways and affect a variety of cellular processes, including cell growth, proliferation, survival, metabolism, and apoptosis. For example, cadmium can affect the BLC-2 family of proteins involved in mitochondrial death via the overexpression of antiapoptotic Bcl-2 and the suppression of proapoptotic (BAX, BAK) mechanisms, thus increasing the resistance of various cells to undergo malignant transformation. Nuclear factor erythroid 2-related factor 2 (Nrf2) is an important regulator of antioxidant enzymes, the level of oxidative stress, and cellular resistance to oxidants and has been shown to act as a double-edged sword in response to arsenic-induced oxidative stress. Another mechanism of significant health threats and heavy metal (e.g., Pb) toxicity involves the substitution of essential metals (e.g., calcium (Ca), copper (Cu), and iron (Fe)) with structurally similar heavy metals (e.g., cadmium (Cd) and lead (Pb)) in the metal-binding sites of proteins. Displaced essential redox metals (copper, iron, manganese) from their natural metal-binding sites can catalyze the decomposition of hydrogen peroxide via the Fenton reaction and generate damaging ROS such as hydroxyl radicals, causing damage to lipids, proteins, and DNA. Conversely, some heavy metals, such as cadmium, can suppress the synthesis of nitric oxide radical (NO·), manifested by altered vasorelaxation and, consequently, blood pressure regulation. Pb-induced oxidative stress has been shown to be indirectly responsible for the depletion of nitric oxide due to its interaction with superoxide radical (O2·-), resulting in the formation of a potent biological oxidant, peroxynitrite (ONOO-). This review comprehensively discusses the mechanisms of heavy metal toxicity and their health effects. Aluminum (Al), cadmium (Cd), arsenic (As), mercury (Hg), lead (Pb), and chromium (Cr) and their roles in the development of gastrointestinal, pulmonary, kidney, reproductive, neurodegenerative (Alzheimer's and Parkinson's diseases), cardiovascular, and cancer (e.g. renal, lung, skin, stomach) diseases are discussed. A short account is devoted to the detoxification of heavy metals by chelation via the use of ethylenediaminetetraacetic acid (EDTA), dimercaprol (BAL), 2,3-dimercaptosuccinic acid (DMSA), 2,3-dimercapto-1-propane sulfonic acid (DMPS), and penicillamine chelators.
- MeSH
- antioxidancia metabolismus MeSH
- bioakumulace MeSH
- látky znečišťující životní prostředí toxicita MeSH
- lidé MeSH
- oxidační stres * účinky léků MeSH
- těžké kovy * toxicita MeSH
- vystavení vlivu životního prostředí škodlivé účinky MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Myoepithelial neoplasms of the skin and soft tissue still represent a confusing and somewhat controversial field in pathology as it appears that this category includes several different entities. However, recent studies have suggested that both apocrine mixed tumors (AMT) and cutaneous myoepitheliomas (CM) harbor identical chromosomal rearrangements involving the PLAG1 gene and hence may represent a morphological spectrum. The aim of the present study was to share our institutional experience with these tumors and specifically focus on studying their immunohistochemical and molecular features to further assess their relatedness. Eleven cases of AMT and 7 cases of CM were collected and analyzed using immunohistochemistry (IHC), PLAG1 FISH, and Archer FusionPlex assay. There were 14 male and 4 female patients with ages ranging from 26 to 85 years (median 55.8 years, mean 58.5 years). AMTs were mainly located in the head and neck (n = 10), while CMs were mainly located in the acral sites (n = 5). PLAG1 IHC was diffusely strongly positive in 14/17 (82%) cases, whereas a single case of AMT diffusely expressed HMGA2. Both tumor groups showed PLAG1 gene fusions which were detected in 6/13 analyzable samples (AMT, n = 4 and CM, n = 2), and included TRPS1::PLAG1 (n = 3), NDRG1::PLAG1 (n = 1), CTNNB1::PLAG1 (n = 1) and a novel PXDNL::PLAG1 fusion (n = 1). The remaining 5 cases were negative, 5 were not analyzable and the single case positive for HMGA2 by IHC revealed a potential HMGA2 gene rearrangement. The cases were further studied by FISH, with 12/17 cases showing PLAG1 gene rearrangement (AMT, n = 8 and CM, n = 4). Altogether, 14/18 cases showed PLAG1 gene rearrangement by at least one of the methods. PLAG1 immunohistochemistry had a 92% specificity and sensitivity. Our study provided additional data to suggest that AMT and CM share overlapping morphological and immunohistochemical features as well as molecular background characterized by PLAG1 gene fusions and thus represent a morphological spectrum. In addition, we identified a novel PXDNL::PLAG1 fusion and suggested that rare cases may harbor HMGA2 gene alterations which seem to be mutually exclusive with PLAG1 gene fusions. The relatedness of these tumors to salivary gland myoepithelial neoplasms and distinctness from eccrine mixed tumors and other skin and soft tissue myoepithelial neoplasms with EWSR1/FUS fusions is discussed.
- MeSH
- DNA vazebné proteiny * genetika MeSH
- dospělí MeSH
- genová přestavba * MeSH
- hybridizace in situ fluorescenční MeSH
- imunohistochemie * MeSH
- lidé středního věku MeSH
- lidé MeSH
- myoepiteliální nádor * genetika patologie MeSH
- nádorové biomarkery * genetika analýza MeSH
- nádory komplexní a smíšené genetika patologie chemie MeSH
- nádory kůže * genetika patologie MeSH
- nádory potních žláz genetika patologie MeSH
- protein HMGA2 * genetika MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
The activity of the light-oxygen-voltage/helix-turn-helix (LOV-HTH) photoreceptor EL222 is regulated through protein-protein and protein-DNA interactions, both triggered by photo-excitation of its flavin mononucleotide (FMN) cofactor. To gain molecular-level insight into the photocycle of EL222, we applied complementary methods: macromolecular X-ray crystallography (MX), nuclear magnetic resonance (NMR) spectroscopy, optical spectroscopies (infrared and UV-visible), molecular dynamics/metadynamics (MD/metaD) simulations, and protein engineering using noncanonical amino acids. Kinetic experiments provided evidence for two distinct EL222 conformations (lit1 and lit2) that become sequentially populated under illumination. These two lit states were assigned to covalently bound N5 protonated, and noncovalently bound hydroquinone forms of FMN, respectively. Only subtle structural differences were observed between the monomeric forms of all three EL222 species (dark, lit1, and lit2). While the dark state is largely monomeric, both lit states undergo monomer-dimer exchange. Furthermore, molecular modeling revealed differential dynamics and interdomain separation times arising from the three FMN states (oxidized, adduct, and reduced). Unexpectedly, all three EL222 species can associate with DNA, but only upon blue-light irradiation, a high population of stable complexes is obtained. Overall, we propose a model of EL222 activation where photoinduced changes in the FMN moiety shift the population equilibrium toward an open conformation that favors self-association and DNA-binding.
- MeSH
- bakteriální proteiny chemie metabolismus MeSH
- DNA vazebné proteiny chemie metabolismus MeSH
- DNA * chemie metabolismus MeSH
- flavinmononukleotid * chemie metabolismus MeSH
- flaviny chemie metabolismus MeSH
- kinetika MeSH
- konformace proteinů MeSH
- krystalografie rentgenová MeSH
- oxidace-redukce * MeSH
- simulace molekulární dynamiky MeSH
- světlo * MeSH
- Thermosynechococcus metabolismus MeSH
- transkripční faktory metabolismus chemie MeSH
- vazba proteinů MeSH
- Publikační typ
- časopisecké články MeSH
Cancer cells display complex genomic aberrations that include large-scale genetic rearrangements and epigenetic modulation that are not easily captured by short-read sequencing. This study presents a novel approach for simultaneous profiling of long-range genetic and epigenetic changes in matched cancer samples, focusing on clear cell renal cell carcinoma (ccRCC). ccRCC is a common kidney cancer subtype frequently characterized by a 3p deletion and the inactivation of the von Hippel-Lindau (VHL) gene. We performed integrated genetic, cytogenetic, and epigenetic analyses on paired tumor and adjacent nontumorous tissue samples. Optical genome mapping identified genomic aberrations as structural and copy number variations, complementing exome-sequencing findings. Single-molecule methylome and hydroxymethylome mapping revealed a significant global reduction in 5hmC level in both sample pairs, and a correlation between both epigenetic signals and gene expression was observed. The single-molecule epigenetic analysis identified numerous differentially modified regions, some implicated in ccRCC pathogenesis, including the genes VHL, PRCC, and PBRM1. Notably, pathways related to metabolism and cancer development were significantly enriched among these differential regions. This study demonstrates the feasibility of integrating optical genome and epigenome mapping for comprehensive characterization of matched tumor and adjacent tissue, uncovering both established and novel somatic aberrations.
- MeSH
- DNA vazebné proteiny MeSH
- epigeneze genetická * genetika MeSH
- epigenom * genetika MeSH
- karcinom z renálních buněk * genetika patologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- mapování chromozomů metody MeSH
- metylace DNA * genetika MeSH
- nádorový supresorový protein VHL genetika MeSH
- nádory ledvin * genetika patologie MeSH
- regulace genové exprese u nádorů MeSH
- transkripční faktory MeSH
- variabilita počtu kopií segmentů DNA * genetika MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
BACKGROUND AND PURPOSE: CNS embryonal tumor with pleomorphic adenoma gene-like 1 (PLAGL1)/pleomorphic adenoma gene-like 2 (PLAGL2) amplification (ET, PLAGL) is a newly identified, highly malignant pediatric tumor. Systematic MRI descriptions of ET, PLAGL are currently lacking. MATERIALS AND METHODS: MRI data from 19 treatment-naïve patients with confirmed ET, PLAGL were analyzed. Evaluation focused on anatomic involvement, tumor localization, MRI signal characteristics, DWI behavior, and the presence of necrosis and hemorrhage. Descriptive statistics (median, interquartile range, percentage) were assessed. RESULTS: Ten patients had PLAGL1 and nine had PLAGL2 amplifications. The solid components of the tumors were often multinodular with heterogeneous enhancement (mild to intermediate in 47% and intermediate to strong in 47% of cases). Nonsolid components included cysts in 47% and necrosis in 84% of the cases. The tumors showed heterogeneous T2WI hyper- and isointensity (74%), relatively little diffusion restriction (ADC values less than contralateral normal-appearing WM in 36% of cases with available DWI), and tendencies toward hemorrhage/calcification (42%). No reliable distinction was found between PLAGL1- and PLAGL2-amplified tumors or compared with other embryonal CNS tumors. CONCLUSIONS: The study contributes to understanding the imaging characteristics of ET, PLAGL. It underscores the need for collaboration in studying rare pediatric tumors and advocates the use of harmonized imaging protocols for better characterization.
- MeSH
- amplifikace genu MeSH
- dítě MeSH
- DNA vazebné proteiny genetika MeSH
- germinální a embryonální nádory diagnostické zobrazování patologie MeSH
- kojenec MeSH
- lidé MeSH
- magnetická rezonanční tomografie * metody MeSH
- mladiství MeSH
- nádorové supresorové proteiny MeSH
- nádory centrálního nervového systému diagnostické zobrazování patologie MeSH
- nádory mozku diagnostické zobrazování patologie MeSH
- předškolní dítě MeSH
- proteiny buněčného cyklu MeSH
- proteiny vázající RNA MeSH
- transkripční faktory genetika MeSH
- Check Tag
- dítě MeSH
- kojenec MeSH
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- předškolní dítě MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Early detection of colorectal cancer (CRC) significantly improves its management and patients' survival. Circular RNAs (circRNAs) are peculiar covalently closed transcripts involved in gene expression modulation whose dysregulation has been extensively reported in CRC cells. However, little is known about their alterations in the early phases of colorectal carcinogenesis. METHODS: In this study, we performed an integrative analysis of circRNA profiles in RNA-sequencing (RNA-Seq) data of 96 colorectal cancers, 27 adenomas, and matched adjacent mucosa tissues. We also investigated the levels of cognate linear transcripts and those of regulating RNA-binding proteins (RBPs). Levels of circRNA-interacting microRNAs (miRNAs) were explored by integrating data of small RNA-Seq performed on the same samples. RESULTS: Our results revealed a significant dysregulation of 34 circRNAs (paired adj. p < 0.05), almost exclusively downregulated in tumor tissues and, prevalently, in early disease stages. This downregulation was associated with decreased expression of circRNA host genes and those encoding for RBPs involved in circRNA biogenesis, including NOVA1, RBMS3, and MBNL1. Guilt-by-association analysis showed that dysregulated circRNAs correlated with increased predicted activity of cell proliferation, DNA repair, and c-Myc signaling pathways. Functional analysis showed interactions among dysregulated circRNAs, RBPs, and miRNAs, which were supported by significant correlations among their expression levels. Findings were validated in independent cohorts and public datasets, and the downregulation of circLPAR1(2,3) and circLINC00632(5) was validated by ddPCR. CONCLUSIONS: These results support that multiple altered regulatory mechanisms may contribute to the reduction of circRNA levels that characterize early colorectal carcinogenesis.
- Publikační typ
- časopisecké články MeSH
Replication stress, particularly in hard-to-replicate regions such as telomeres and centromeres, leads to the accumulation of replication intermediates that must be processed to ensure proper chromosome segregation. In this study, we identify a critical role for the interaction between RECQ4 and MUS81 in managing such stress. We show that RECQ4 physically interacts with MUS81, targeting it to specific DNA substrates and enhancing its endonuclease activity. Loss of this interaction, results in significant chromosomal segregation defects, including the accumulation of micronuclei, anaphase bridges, and ultrafine bridges (UFBs). Our data further demonstrate that the RECQ4-MUS81 interaction plays an important role in ALT-positive cells, where MUS81 foci primarily colocalise with telomeres, highlighting its role in telomere maintenance. We also observe that a mutation associated with Rothmund-Thomson syndrome, which produces a truncated RECQ4 unable to interact with MUS81, recapitulates these chromosome instability phenotypes. This underscores the importance of RECQ4-MUS81 in safeguarding genome integrity and suggests potential implications for human disease. Our findings demonstrate the RECQ4-MUS81 interaction as a key mechanism in alleviating replication stress at hard-to-replicate regions and highlight its relevance in pathological conditions such as RTS.
- MeSH
- chromozomální nestabilita MeSH
- DNA vazebné proteiny * metabolismus genetika MeSH
- endonukleasy * metabolismus genetika MeSH
- helikasy RecQ * metabolismus genetika MeSH
- homeostáza telomer MeSH
- lidé MeSH
- mutace MeSH
- replikace DNA * MeSH
- Rothmundův-Thomsonův syndrom * genetika metabolismus MeSH
- segregace chromozomů MeSH
- telomery * metabolismus genetika MeSH
- vazba proteinů MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Cannabidiol (CBD) is one of the principal constituents of Cannabis Sativa with no psychoactive properties. CBD is a promising neuroprotective compound bearing anti-inflammatory and antioxidant properties. However, considering its low solubility, CBD delivery to the retina represents an unresolved issue. The first aim was to investigate the potential neuroprotective effects of CBD in an in vivo model of retinal excitotoxicity induced by α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA). Rats underwent intravitreal co-injection of AMPA (42 nmol) and CBD (10-4 M). The neuroprotective effect of CBD was investigated with histology and immunohistochemical evaluation of inflammatory and oxidative stress biomarkers. CBD reversed the AMPA-induced total retinal, inner nuclear layer and inner plexiform layer shrinkage and loss of amacrine cells. Moreover, CBD decreased the AMPA induced number of cleaved caspase-3, Iba-1 and nitrotyrosine (NT) positive cells. Based on this evidence, we developed a nanotechnological formulation of CBD to overcome critical issues related to its eye delivery. Particularly, nanostructured lipid carriers (NLC) loaded with CBD were prepared, optimized and characterized. Due to the optimal physicochemical characteristics, CBD-NLC3 has been selected and the in vitro release profile has been investigated. Additionally, CBD-NLC3 was topically administered to rats, and retinal CBD levels were determined. CBD-NLC3 formulation, after a single topical administration, efficiently delivered CBD in the retina (Cmax = 98 ± 25.9 ng/mg; Tmax = 60 min), showing a high translational value. In conclusion, these findings showed a good PD/PK profile of CBD warranting further pre-clinical and clinical evaluation of the new formulation for the treatment of retinal degenerative diseases.
- MeSH
- kanabidiol * farmakokinetika farmakologie aplikace a dávkování MeSH
- kaspasa 3 metabolismus MeSH
- krysa rodu rattus MeSH
- kyselina alfa-amino-3-hydroxy-5-methyl-4-isoxazolpropionová toxicita MeSH
- mikrofilamentové proteiny metabolismus MeSH
- modely nemocí na zvířatech MeSH
- neuroprotektivní látky * farmakokinetika farmakologie aplikace a dávkování MeSH
- nosiče léků chemie MeSH
- oxidační stres účinky léků MeSH
- potkani Wistar MeSH
- proteiny vázající vápník MeSH
- retina * účinky léků metabolismus patologie MeSH
- tyrosin analogy a deriváty MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Single-cell RNA-seq methods can be used to delineate cell types and states at unprecedented resolution but do little to explain why certain genes are expressed. Single-cell ATAC-seq and multiome (ATAC + RNA) have emerged to give a complementary view of the cell state. It is however unclear what additional information can be extracted from ATAC-seq data besides transcription factor binding sites. Here, we show that ATAC-seq telomere-like reads counter-inituively cannot be used to infer telomere length, as they mostly originate from the subtelomere, but can be used as a biomarker for chromatin condensation. Using long-read sequencing, we further show that modern hyperactive Tn5 does not duplicate 9 bp of its target sequence, contrary to common belief. We provide a new tool, Telomemore, which can quantify nonaligning subtelomeric reads. By analyzing several public datasets and generating new multiome fibroblast and B-cell atlases, we show how this new readout can aid single-cell data interpretation. We show how drivers of condensation processes can be inferred, and how it complements common RNA-seq-based cell cycle inference, which fails for monocytes. Telomemore-based analysis of the condensation state is thus a valuable complement to the single-cell analysis toolbox.
- MeSH
- analýza jednotlivých buněk * metody MeSH
- B-lymfocyty metabolismus cytologie MeSH
- buněčný cyklus * genetika MeSH
- ChiP sekvenování metody MeSH
- chromatin * metabolismus chemie genetika MeSH
- fibroblasty metabolismus cytologie MeSH
- lidé MeSH
- sekvenování transkriptomu metody MeSH
- telomery * genetika MeSH
- vazebná místa MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH