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

AIMS: Embryonal tumours with PLAGL1 or PLAGL2 amplification (ET, PLAGL) show substantial heterogeneity regarding their clinical characteristics and have been treated inconsistently, resulting in diverse outcomes. In this study, we aimed to evaluate the clinical behaviour of ET, PLAGL and elucidate their response pattern across the different applied treatment regimens. METHODS: We conducted an in-depth retrospective analysis of clinical and serial imaging data of 18 patients with ET, PLAGL (nine each of PLAGL1 and PLAGL2 amplified). RESULTS: Patients with PLAGL1-amplified tumours (ET, PLAGL1) had fewer relapses (3/9), while PLAGL2-amplified tumours (ET, PLAGL2) were prone to early relapse or progression (8/9) and to distant, leptomeningeal and intraventricular relapses. Progression-free survival differed significantly between the subtypes (log-rank test, p = 0.0055). Postoperative treatment included chemotherapy (n = 17, various protocols), alone (n = 8) or combined with radiotherapy (n = 9). Responses to chemotherapy were observed in both subtypes, and incomplete resection was not associated with inferior survival. All three survivors with ET, PLAGL2 were treated with induction and high-dose chemotherapy with (n = 1-low-dose CSI and boost) or without (n = 2) radiotherapy, whereas five patients with less intensive chemotherapy relapsed. All six survivors with ET, PLAGL1 were treated with conventional chemotherapy regimens, with (n = 4-local radiotherapy n = 3; CSI and boost n = 1) or without (n = 2) radiotherapy. Two patients with ET, PLAGL1 relapsed after 8 years. CONCLUSIONS: Adjuvant therapy should be considered for all ET, PLAGL patients: Patients with ET, PLAGL2 might benefit from intensified chemotherapy regimens. In contrast, patients with ET, PLAGL1 showed superior outcomes without high-dose chemotherapy or craniospinal irradiation.

• MeSH
• amplifikace genu MeSH
• dítě MeSH
• DNA vazebné proteiny * genetika   MeSH
• dospělí MeSH
• germinální a embryonální nádory * genetika   terapie   patologie   diagnostické zobrazování   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• nádory centrálního nervového systému * genetika   terapie   patologie   diagnostické zobrazování   MeSH
• nádory mozku * genetika   terapie   MeSH
• předškolní dítě MeSH
• retrospektivní studie MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH

BACKGROUND: Targeted alpha therapy represents an advanced and rapidly evolving form of precision cancer treatment with increasing importance in recent years. The alpha-emitter 225Ac plays a key role in this clinical development due to its attractive physical and chemical properties. In this context, the macropa chelator has favorable characteristics in terms of labeling conditions and complex stability, making its derivatives exceptionally appealing for 225Ac-labeling of heat-sensitive biomolecules. However, preclinical evaluation of such 225Ac-containing molecules and comprehensive assessment of their pharmacokinetics, dosimetry and radiobiology necessitate a suitable diagnostic counterpart. Due to its attractive radiation properties, 133La represents an adequate positron-emitting radionuclide to form a matched pair with 225Ac for macropa-based radiopharmaceuticals. Herein, we describe the preparation and radiopharmacological characterization of macropa-functionalized, 133La/225Ac-labeled single-domain antibodies (sdAbs) targeting the epidermal growth factor receptor (EGFR) to demonstrate the general suitability of this theranostic pair of radionuclides. RESULTS: The synthesis of a clickable, bicyclononyne-modified macropa chelator and its site-specific conjugation to azide-modified, monovalent and biparatopic sdAbs is presented. Subsequent labeling at room temperature (rt) for 15 min resulted in molar activities of 30 MBq/nmol for 133La and 0.5 MBq/nmol for 225Ac, respectively. In vitro studies using the 133La-labeled sdAbs revealed comparable binding characteristics, but an enhanced cellular internalization of the biparatopic variant compared to its monovalent counterparts. This increased uptake consequently resulted in higher cytotoxicity of the 225Ac-labeled biparatopic conjugate. In vivo PET imaging of the 133La-labeled conjugates indicated comparable uptake and retention of the mono- and biparatopic variants in liver and kidneys, with the former showing slightly higher tumor accumulation. Ex vivo biodistribution studies conducted with 225Ac-labeled conjugates largely confirmed the findings obtained by PET imaging, albeit with a marginally higher tumor accumulation of the biparatopic 225Ac-radioimmunoconjugate. Final histological examinations of tumor and kidney tissues showed DNA damage in the renal cortex of the 225Ac-radioimmunoconjugate-treated mice, but no differences in the number of γ-H2AX-positive cells in the corresponding tumor tissues could be detected. CONCLUSIONS: We present a comprehensive study on the theranostic application of 133La and 225Ac for antibody-based biomolecules and lay the foundation for the future application of this matched pair of radionuclides towards labeling of heat-sensitive, macropa-functionalized radiopharmaceuticals in general. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s41181-025-00354-7.

• Publikační typ
• časopisecké články MeSH

Topoisomerase II alpha and beta (TOP2A and TOP2B) isoenzymes perform essential and non-redundant cellular functions. Anthracyclines induce their potent anti-cancer effects primarily via TOP2A, but at the same time they induce a dose limiting cardiotoxicity through TOP2B. Here we describe the development of the obex class of TOP2 inhibitors that bind to a previously unidentified druggable pocket in the TOP2 ATPase domain to act as allosteric catalytic inhibitors by locking the ATPase domain conformation with the capability of isoform-selective inhibition. Through rational drug design we have developed topobexin, which interacts with residues that differ between TOP2A and TOP2B to provide inhibition that is both selective for TOP2B and superior to dexrazoxane. Topobexin is a potent protectant against chronic anthracycline cardiotoxicity in an animal model. This demonstration of TOP2 isoform-specific inhibition underscores the broader potential to improve drug specificity and minimize adverse effects in various medical treatments.

• MeSH
• antracykliny * škodlivé účinky   farmakologie   MeSH
• DNA-topoisomerasy typu II * metabolismus   chemie   MeSH
• inhibitory topoisomerasy II * farmakologie   chemie   MeSH
• kardiotonika * farmakologie   chemie   MeSH
• kardiotoxicita * prevence a kontrola   MeSH
• lidé MeSH
• myši MeSH
• proteiny vázající poly-ADP-ribosu antagonisté a inhibitory   metabolismus   chemie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články 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 ABCB1 gene, encoding the ATP-dependent translocase ABCB1, plays a crucial role in the clearance of amyloid-beta (Aβ) peptides and the transport of cholesterol, implicating it in the pathogenesis of Alzheimer's disease. The study aims to investigate the association between polymorphisms in the ABCB1 gene and cognitive decline in individuals with mild cognitive impairment (MCI), particularly focusing on language function. A longitudinal cohort study involving 1 005 participants from the Czech Brain Aging Study was conducted. Participants included individuals with Alzheimer's disease, amnestic MCI, non-amnestic MCI, subjective cognitive decline, and healthy controls. Next-generation sequencing was utilized to analyze the entire ABCB1 gene. Cognitive performance was assessed using a comprehensive battery of neuropsychological tests, including the Boston Naming Test and the semantic verbal fluency test. Ten ABCB1 polymorphisms (rs55912869, rs56243536, rs10225473, rs10274587, rs2235040, rs12720067, rs12334183, rs10260862, rs201620488, and rs28718458) were significantly associated with cognitive performance, particularly in language decline among amnestic MCI patients. In silico analyses revealed that some of these polymorphisms may affect the binding sites for transcription factors (HNF-3alpha, C/EBPβ, GR-alpha) and the generation of novel exonic splicing enhancers. Additionally, polymorphism rs55912869 was identified as a potential binding site for the microRNA hsa-mir-3163. Our findings highlight the significant role of ABCB1 polymorphisms in cognitive decline, particularly in language function, among individuals with amnestic MCI. These polymorphisms may influence gene expression and function through interactions with miRNAs, transcription factors, and alternative splicing mechanisms.

• MeSH
• Alzheimerova nemoc genetika   MeSH
• jednonukleotidový polymorfismus * MeSH
• kognitivní dysfunkce * genetika   MeSH
• lidé MeSH
• longitudinální studie MeSH
• neuropsychologické testy MeSH
• P-glykoproteiny genetika   MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• vysoce účinné nukleotidové sekvenování MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH

Integral membrane proteins carry out essential functions in the cell, and their activities are often modulated by specific protein-lipid interactions in the membrane. Here, we elucidate the intricate role of cardiolipin (CDL), a regulatory lipid, as a stabilizer of membrane proteins and their complexes. Using the in silico-designed model protein TMHC4_R (ROCKET) as a scaffold, we employ a combination of molecular dynamics simulations and native mass spectrometry to explore the protein features that facilitate preferential lipid interactions and mediate stabilization. We find that the spatial arrangement of positively charged residues as well as local conformational flexibility are factors that distinguish stabilizing from non-stabilizing CDL interactions. However, we also find that even in this controlled, artificial system, a clear-cut distinction between binding and stabilization is difficult to attain, revealing that overlapping lipid contacts can partially compensate for the effects of binding site mutations. Extending our insights to naturally occurring proteins, we identify a stabilizing CDL site within the E. coli rhomboid intramembrane protease GlpG and uncover its regulatory influence on enzyme substrate preference. In this work, we establish a framework for engineering functional lipid interactions, paving the way for the design of proteins with membrane-specific properties or functions.

• MeSH
• DNA vazebné proteiny MeSH
• endopeptidasy metabolismus   chemie   genetika   MeSH
• Escherichia coli metabolismus   genetika   MeSH
• kardiolipiny * metabolismus   chemie   MeSH
• membránové proteiny * metabolismus   chemie   genetika   MeSH
• proteinové inženýrství * MeSH
• proteiny z Escherichia coli * metabolismus   chemie   genetika   MeSH
• simulace molekulární dynamiky MeSH
• vazba proteinů MeSH
• Publikační typ
• časopisecké články MeSH

Previous research indicated that the cytotoxic activity of the antitumor platinum(II) complex [Pt(1S,2S-diaminocyclohexane)(5,6-dimethyl-1,10-phenanthroline)]2+ (56MESS) was not primarily attributed to DNA binding, despite the complex being confirmed to localize also in the nucleus. In this study, we have demonstrated that the antiproliferative activity of 56MESS indeed involves DNA binding. Furthermore, in addition to binding duplex DNA, the complex also interacts with non-canonical secondary DNA structures, such as G-quadruplexes (G4s) and i-Motifs (iMs). This interaction leads to the suppression of G-regulated oncogene expression and disrupts key enzymatic processes associated with DNA, potentially contributing to DNA damage and the biological activity of 56MESS. These findings build upon previously published results, revealing that the anticancer activity of 56MESS is significantly more multifaceted than previously understood, involving multiple distinct mechanisms.

• MeSH
• DNA metabolismus   chemie   MeSH
• down regulace * účinky léků   MeSH
• G-kvadruplexy * účinky léků   MeSH
• lidé MeSH
• nádorové buněčné linie MeSH
• organoplatinové sloučeniny * farmakologie   chemie   MeSH
• poškození DNA * účinky léků   MeSH
• proliferace buněk účinky léků   MeSH
• protinádorové látky * farmakologie   chemie   MeSH
• protoonkogenní proteiny c-myc * genetika   metabolismus   MeSH
• protoonkogenní proteiny p21(ras) * genetika   metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

G-quadruplexes (G4s) are functional elements of the human genome, some of which inhibit DNA replication. We investigated replication of G4s within highly abundant microsatellite (GGGA, GGGT) and transposable element (L1 and SVA) sequences. We found that genome-wide, numerous motifs are located preferentially on the replication leading strand and the transcribed strand templates. We directly tested replicative polymerase ε and δ holoenzyme inhibition at these G4s, compared to low abundant motifs. For all G4s, DNA synthesis inhibition was higher on the G-rich than C-rich strand or control sequence. No single G4 was an absolute block for either holoenzyme; however, the inhibitory potential varied over an order of magnitude. Biophysical analyses showed the motifs form varying topologies, but replicative polymerase inhibition did not correlate with a specific G4 structure. Addition of the G4 stabilizer pyridostatin severely inhibited forward polymerase synthesis specifically on the G-rich strand, enhancing G/C strand asynchrony. Our results reveal that replicative polymerase inhibition at every G4 examined is distinct, causing complementary strand synthesis to become asynchronous, which could contribute to slowed fork elongation. Altogether, we provide critical information regarding how replicative eukaryotic holoenzymes navigate synthesis through G4s naturally occurring thousands of times in functional regions of the human genome.

• MeSH
• aminochinoliny MeSH
• DNA-polymerasa II * antagonisté a inhibitory   metabolismus   MeSH
• DNA-polymerasa III * antagonisté a inhibitory   metabolismus   MeSH
• DNA chemie   MeSH
• G-kvadruplexy * MeSH
• genom lidský * MeSH
• holoenzymy metabolismus   MeSH
• kyseliny pikolinové farmakologie   MeSH
• lidé MeSH
• mikrosatelitní repetice MeSH
• proteiny vázající poly-ADP-ribosu MeSH
• replikace DNA * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH