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The Journal of Antimicrobial... Aug 2023Fluoroquinolones (FQs) are potent and broad-spectrum antibiotics commonly used to treat MDR bacterial infections, but bacterial resistance to FQs has emerged and spread...
BACKGROUND
Fluoroquinolones (FQs) are potent and broad-spectrum antibiotics commonly used to treat MDR bacterial infections, but bacterial resistance to FQs has emerged and spread rapidly around the world. The mechanisms for FQ resistance have been revealed, including one or more mutations in FQ target genes such as DNA gyrase (gyrA) and topoisomerase IV (parC). Because therapeutic treatments for FQ-resistant bacterial infections are limited, it is necessary to develop novel antibiotic alternatives to minimize or inhibit FQ-resistant bacteria.
OBJECTIVES
To examine the bactericidal effect of antisense peptide-peptide nucleic acids (P-PNAs) that can block the expression of DNA gyrase or topoisomerase IV in FQ-resistant Escherichia coli (FRE).
METHODS
A set of antisense P-PNA conjugates with a bacterial penetration peptide were designed to inhibit the expression of gyrA and parC and were evaluated for their antibacterial activities.
RESULTS
Antisense P-PNAs, ASP-gyrA1 and ASP-parC1, targeting the translational initiation sites of their respective target genes significantly inhibited the growth of the FRE isolates. In addition, ASP-gyrA3 and ASP-parC2, which bind to the FRE-specific coding sequence within the gyrA and parC structural genes, respectively, showed selective bactericidal effects against FRE isolates.
CONCLUSIONS
Our results demonstrate the potential of targeted antisense P-PNAs as antibiotic alternatives against FQ-resistance bacteria.
Topics: Fluoroquinolones; Escherichia coli; Peptide Nucleic Acids; DNA Gyrase; DNA Topoisomerase IV; Anti-Bacterial Agents; Bacteria; Mutation; Microbial Sensitivity Tests; Drug Resistance, Bacterial
PubMed: 37390375
DOI: 10.1093/jac/dkad203 -
Archiv Der Pharmazie Jul 2023A series of seventeen 1,8-naphthyridine derivatives (5a-5q) conjugated at N to various substituted phenyl rings were designed and synthesized as potential topoisomerase...
A series of seventeen 1,8-naphthyridine derivatives (5a-5q) conjugated at N to various substituted phenyl rings were designed and synthesized as potential topoisomerase II (Topo II) inhibitors. The antiproliferative activity of the target compounds against three cancer cell lines showed that compounds 5g and 5p had the highest antiproliferative activity. In addition, 5p and 5g displayed a high selectivity index (SI) for cancer cells when tested on WI38 normal cells, whereby compound 5p showed the highest SI. Furthermore, 5g and 5p induced cell cycle arrest at the S and G1/S phases, respectively, triggering apoptosis in HepG-2 cells. The in vitro Topo II inhibitory effect (plasmid-based) of both compounds revealed that 5p had better inhibition of Topo II. In addition, 5p displayed potent topoisomerase IIβ inhibitory effect when compared to known topoisomerase inhibitors (doxorubicin and topotecan). Molecular docking proposed a unique binding pattern of 5p in the etoposide binding pocket of topoisomerase IIβ, endorsing its potential role as a Topo II poison. Accordingly, 5p was chosen for radioiodination to study the degree of tumor localization following administration in solid tumor-bearing mice. The radioiodinated 5p showed a selective localization at the tumor site, which further confirmed the value of 5p as a lead 1,8-naphthyridine anticancer agent.
Topics: Animals; Mice; Molecular Structure; Structure-Activity Relationship; Molecular Docking Simulation; Naphthyridines; Cell Line, Tumor; Iodine Radioisotopes; Drug Design; Antineoplastic Agents; Topoisomerase II Inhibitors; DNA Topoisomerases, Type II; Apoptosis
PubMed: 37080944
DOI: 10.1002/ardp.202300035 -
Clinical Genetics Aug 2023DNA Topoisomerase IIβ (TOP2B) acts on DNA topology during transcription and has a critical role in neural development. Heterozygous pathogenic changes in its encoding... (Review)
Review
DNA Topoisomerase IIβ (TOP2B) acts on DNA topology during transcription and has a critical role in neural development. Heterozygous pathogenic changes in its encoding gene, TOP2B (MIM *126431), has been linked with three overlapping phenotypes characterized by immunodeficiency, acral and urogenital anomalies: Hoffman, BILU and Ablepharon-macrostomia-like syndrome. We herein report on a mother and two sons with distinct TOP2B-phenotype. Two males reported further delineated genital phenotype of males and all reported patients were reviewed for genotype-phenotype correlation. We believe the patients reported herein along with the previously defined 11 represent a phenotypic spectrum from mild-to-severe immunological, acral and urogenital involvement, for which we propose the acronym "TOP2B-related Immunodeficiency and Congenital Anomalies Spectrum (TICAS)".
Topics: Male; Humans; DNA-Binding Proteins; DNA; Phenotype; Poly-ADP-Ribose Binding Proteins; DNA Topoisomerases, Type II
PubMed: 37068767
DOI: 10.1111/cge.14341 -
Nucleic Acids Research Dec 2023Chromatin remodeling is essential to allow full development of alternative gene expression programs in response to environmental changes. In fission yeast, oxidative...
Chromatin remodeling is essential to allow full development of alternative gene expression programs in response to environmental changes. In fission yeast, oxidative stress triggers massive transcriptional changes including the activation of hundreds of genes, with the participation of histone modifying complexes and chromatin remodelers. DNA transcription is associated to alterations in DNA topology, and DNA topoisomerases facilitate elongation along gene bodies. Here, we test whether the DNA topoisomerase Top1 participates in the RNA polymerase II-dependent activation of the cellular response to oxidative stress. Cells lacking Top1 are resistant to H2O2 stress. The transcriptome of Δtop1 strain was not greatly affected in the absence of stress, but activation of the anti-stress gene expression program was more sustained than in wild-type cells. Top1 associated to stress open reading frames. While the nucleosomes of stress genes are partially and transiently evicted during stress, the chromatin configuration remains open for longer times in cells lacking Top1, facilitating RNA polymerase II progression. We propose that, by removing DNA tension arising from transcription, Top1 facilitates nucleosome reassembly and works in synergy with the chromatin remodeler Hrp1 as opposing forces to transcription and to Snf22 / Hrp3 opening remodelers.
Topics: Chromatin; Chromatin Assembly and Disassembly; DNA; DNA Topoisomerases, Type I; Hydrogen Peroxide; Nucleosomes; RNA Polymerase II; Schizosaccharomyces; Transcription, Genetic
PubMed: 37956308
DOI: 10.1093/nar/gkad1066 -
Heliyon Oct 2023Chalcones and their derivatives have been widely studied due to their versatile pharmacological and biological activities, such as anti-inflammatory, antibacterial,... (Review)
Review
Chalcones and their derivatives have been widely studied due to their versatile pharmacological and biological activities, such as anti-inflammatory, antibacterial, antiviral, and antitumor effects. These compounds have shown suitable antiviral effects through the selective targeting of a variety of viral enzymes, including lactate dehydrogenase, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), fumarate reductase, protein tyrosine phosphatase, topoisomerase-II, protein kinases, integrase/protease, and lactate/isocitrate dehydrogenase, among others. Chalcones and their derivatives have displayed excellent potential for combating pathogenic bacteria and fungi (especially, multidrug-resistant bacteria). However, relevant mechanisms should be further explored, focusing on inhibitory effects against DNA gyrase B, UDP-N-acetylglucosamine enolpyruvyl transferase (MurA), and efflux pumps (e.g. NorA), among others. In addition, the antifungal and antiparasitic activities of these compounds (e.g., antitrypanosomal and antileishmanial properties) have prompted additional explorations. Nonetheless, systematic analysis of the relevant mechanisms, biosafety issues, and pharmacological properties, as well as clinical translation studies, are vital for practical applications. Herein, recent advancements pertaining to the antibacterial, antiviral, antiparasitic, and antifungal activities of chalcones and their derivatives are deliberated, focusing on the relevant mechanisms of action, crucial challenges, and future prospects. Furthermore, due to the great importance of greener and more sustainable synthesis of these valuable compounds, especially on an industrial scale, the progress made in this field has been briefly discussed. Hopefully, this review can serve as a catalyst for researchers to delve deeper into the exploration and designing of novel chalcone compounds with medicinal properties, especially against pathogenic viruses and multidrug-resistant bacteria as major causes of concern for human health.
PubMed: 37810815
DOI: 10.1016/j.heliyon.2023.e20428 -
Cancer Biology & Therapy Dec 2024Ovarian cancer (OC) is a form of gynecological malignancy that is associated with worse patient outcomes than any other cancer of the female reproductive tract....
Ovarian cancer (OC) is a form of gynecological malignancy that is associated with worse patient outcomes than any other cancer of the female reproductive tract. Topoisomerase II α (TOP2A) is commonly regarded as an oncogene that is associated with malignant disease progression in a variety of cancers, its mechanistic functions in OC have yet to be firmly established. We explored the role of TOP2A in OC through online databases, clinical samples, in vitro and in vivo experiments. And initial analyses of public databases revealed high OC-related TOP2A expression in patient samples that was related to poorer prognosis. This was confirmed by clinical samples in which TOP2A expression was elevated in OC relative to healthy tissue. Kaplan-Meier analyses further suggested that higher TOP2A expression levels were correlated with worse prognosis in OC patients. In vitro, TOP2A knockdown resulted in the inhibition of OC cell proliferation, with cells entering G1 phase arrest and undergoing consequent apoptotic death. In rescue assays, TOP2A was confirmed to regulate cell proliferation and cell cycle through AKT/mTOR pathway activity. Mouse model experiments further affirmed the key role that TOP2A plays as a driver of OC cell proliferation. These data provide strong evidence supporting TOP2A as an oncogenic mediator and prognostic biomarker related to OC progression and poor outcomes. At the mechanistic level, TOP2A can control tumor cell growth via AKT/mTOR pathway modulation. These preliminary results provide a foundation for future research seeking to explore the utility of TOP2A inhibitor-based combination treatment regimens in platinum-resistant recurrent OC patients.
Topics: Animals; Female; Humans; Mice; Carcinoma, Ovarian Epithelial; Cell Proliferation; DNA Topoisomerases, Type II; Ovarian Neoplasms; Proto-Oncogene Proteins c-akt; TOR Serine-Threonine Kinases
PubMed: 38445610
DOI: 10.1080/15384047.2024.2325126 -
Cell Death & Disease Jan 2024DNA topoisomerase II (TOP2) is an enzyme that performs a critical function in manipulating DNA topology during replication, transcription, and chromosomal compaction by...
DNA topoisomerase II (TOP2) is an enzyme that performs a critical function in manipulating DNA topology during replication, transcription, and chromosomal compaction by forming a vital intermediate known as the TOP2-DNA cleavage complex (TOP2cc). Although the TOP2cc is often transient, stabilization can be achieved by TOP2 poisons, a family of anti-cancer chemotherapeutic agents targeting TOP2, such as etoposide (VP-16), and then induce double-strand breaks (DSBs) in cellular DNA. TOP2cc first needs to be proteolyzed before it can be processed by TDP2 for the removal of these protein adducts and to produce clean DNA ends necessary for proper repair. However, the mechanism by which TOP2βcc is proteolyzed has not been thoroughly studied. In this study, we report that after exposure to VP-16, MDM2, a RING-type E3 ubiquitin ligase, attaches to TOP2β and initiates polyubiquitination and proteasomal degradation. Mechanistically, during exposure to VP-16, TOP2β binds to DNA to form TOP2βcc, which promotes MDM2 binding and subsequent TOP2β ubiquitination and degradation, and results in a decrease in TOP2βcc levels. Biologically, MDM2 inactivation abrogates TOP2β degradation, stabilizes TOP2βcc, and subsequently increases the number of TOP2β-concealed DSBs, resulting in the rapid death of cancer cells via the apoptotic process. Furthermore, we demonstrate the combination activity of VP-16 and RG7112, an MDM2 inhibitor, in the xenograft tumor model and in situ lung cancer mouse model. Taken together, the results of our research reveal an underlying mechanism by which MDM2 promotes cancer cell survival in the presence of TOP2 poisons by activating proteolysis of TOP2βcc in a p53-independent manner, and provides a rationale for the combination of MDM2 inhibitors with TOP2 poisons for cancer therapy.
Topics: Animals; Humans; Mice; Disease Models, Animal; DNA; DNA Topoisomerases, Type II; DNA-Binding Proteins; Etoposide; Phosphoric Diester Hydrolases; Proteolysis; Proto-Oncogene Proteins c-mdm2; Tumor Suppressor Protein p53
PubMed: 38263255
DOI: 10.1038/s41419-024-06474-3 -
Journal of Cell Communication and... Dec 2023The treatment of cancer patients has been prohibited by chemoresistance. Doxorubicin (DOX) is an anti-tumor compound disrupting proliferation and triggering cell cycle... (Review)
Review
The treatment of cancer patients has been prohibited by chemoresistance. Doxorubicin (DOX) is an anti-tumor compound disrupting proliferation and triggering cell cycle arrest via inhibiting activity of topoisomerase I and II. miRNAs are endogenous RNAs localized in cytoplasm to reduce gene level. Abnormal expression of miRNAs changes DOX cytotoxicity. Overexpression of tumor-promoting miRNAs induces DOX resistance, while tumor-suppressor miRNAs inhibit DOX resistance. The miRNA-mediated regulation of cell death and hallmarks of cancer can affect response to DOX chemotherapy in tumor cells. The transporters such as P-glycoprotein are regulated by miRNAs in DOX chemotherapy. Upstream mediators including lncRNAs and circRNAs target miRNAs in affecting capacity of DOX. The response to DOX chemotherapy can be facilitated after administration of agents that are mostly phytochemicals including curcumol, honokiol and ursolic acid. These agents can regulate miRNA expression increasing DOX's cytotoxicity. Since delivery of DOX alone or in combination with other drugs and genes can cause synergistic impact, the nanoparticles have been introduced for drug sensitivity. The non-coding RNAs determine the response of tumor cells to doxorubicin chemotherapy. microRNAs play a key role in this case and they can be sponged by lncRNAs and circRNAs, showing interaction among non-coding RNAs in the regulation of doxorubicin sensitivity.
PubMed: 38019354
DOI: 10.1007/s12079-023-00789-0 -
A dual-function SNF2 protein drives chromatid resolution and nascent transcripts removal in mitosis.EMBO Reports Sep 2023Mitotic chromatin is largely assumed incompatible with transcription due to changes in the transcription machinery and chromosome architecture. However, the mechanisms...
Mitotic chromatin is largely assumed incompatible with transcription due to changes in the transcription machinery and chromosome architecture. However, the mechanisms of mitotic transcriptional inactivation and their interplay with chromosome assembly remain largely unknown. By monitoring ongoing transcription in Drosophila early embryos, we reveal that eviction of nascent mRNAs from mitotic chromatin occurs after substantial chromosome compaction and is not promoted by condensin I. Instead, we show that the timely removal of transcripts from mitotic chromatin is driven by the SNF2 helicase-like protein Lodestar (Lds), identified here as a modulator of sister chromatid cohesion defects. In addition to the eviction of nascent transcripts, we uncover that Lds cooperates with Topoisomerase 2 to ensure efficient sister chromatid resolution and mitotic fidelity. We conclude that the removal of nascent transcripts upon mitotic entry is not a passive consequence of cell cycle progression and/or chromosome compaction but occurs via dedicated mechanisms with functional parallelisms to sister chromatid resolution.
Topics: Animals; Cell Cycle Proteins; Chromatids; Chromatin; DNA Topoisomerases, Type II; Drosophila; Mitosis
PubMed: 37462213
DOI: 10.15252/embr.202256463 -
Journal of Virology Nov 2023African swine fever virus (ASFV) is a highly fatal swine disease that severely affects the pig industry. Although ASFV has been prevalent for more than 100 years,...
African swine fever virus (ASFV) is a highly fatal swine disease that severely affects the pig industry. Although ASFV has been prevalent for more than 100 years, effective vaccines or antiviral strategies are still lacking. In this study, we identified four strains that inhibited ASFV proliferation . Pigs fed with liquid biologics or powders derived from four strains mixed with pellet feed showed reduced morbidity and mortality when challenged with ASFV. Further analysis showed that the antiviral activity of was based on its metabolites arctiin and genistein interfering with the function of viral topoisomerase II. Our findings offer a promising new strategy for the prevention and control of ASFV that may significantly alleviate the economic losses in the pig industry.
Topics: Animals; African Swine Fever; African Swine Fever Virus; Antiviral Agents; Bacillus subtilis; DNA Topoisomerases, Type II; Genistein; Swine
PubMed: 37929962
DOI: 10.1128/jvi.00719-23