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Cancers Jun 2024Antibacterial fluoroquinolones have emerged as potential anticancer drugs, thus prompting the synthesis of novel molecules with improved cytotoxic characteristics....
Antibacterial fluoroquinolones have emerged as potential anticancer drugs, thus prompting the synthesis of novel molecules with improved cytotoxic characteristics. Ciprofloxacin and norfloxacin derivatives, previously synthesized by our group, showed higher anticancer potency than their progenitors. However, no information about their mechanisms of action was reported. In this study, we selected the most active among these promising molecules and evaluated, on a panel of breast (including those triple-negative) and bladder cancer cell lines, their ability to induce cell cycle alterations and apoptotic and necrotic cell death through cytofluorimetric studies. Furthermore, inhibitory effects on cellular migration, metalloproteinase, and/or acetylated histone protein levels were also evaluated by the scratch/wound healing assay and Western blot analyses, respectively. Finally, the DNA relaxation assay was performed to confirm topoisomerase inhibition. Our results indicate that the highest potency previously observed for the derivatives could be related to their ability to induce G2/M cell cycle arrest and apoptotic and/or necrotic cell death. Moreover, they inhibited cellular migration, probably by reducing metalloproteinase levels and histone deacetylases. Finally, topoisomerase inhibition, previously observed in silico, was confirmed. In conclusion, structural modifications of progenitor fluoroquinolones resulted in potent anticancer derivatives possessing multiple mechanisms of action, potentially exploitable for the treatment of aggressive/resistant cancers.
PubMed: 38927932
DOI: 10.3390/cancers16122227 -
Future Oncology (London, England) Jun 2024Patients with early-stage triple-negative breast cancer (TNBC) with residual invasive disease after neoadjuvant therapy have a high risk of recurrence even with...
Patients with early-stage triple-negative breast cancer (TNBC) with residual invasive disease after neoadjuvant therapy have a high risk of recurrence even with neoadjuvant and adjuvant treatment with pembrolizumab. Sacituzumab govitecan, a Trop-2-directed antibody-drug conjugate with a topoisomerase I inhibitor payload, improved progression-free survival (PFS) and overall survival (OS) versus chemotherapy in patients with pre-treated metastatic TNBC. Moreover, preclinical data suggest that topoisomerase I inhibitors may enhance the effects of immune checkpoint inhibitors through activation of the cGAS-STING pathway. Here we describe the international randomized phase III AFT-65/ASCENT-05/OptimICE-RD trial, which evaluates the efficacy and safety of sacituzumab govitecan plus pembrolizumab versus treatment of physician's choice (pembrolizumab ± capecitabine) among patients with early-stage TNBC with residual invasive disease after neoadjuvant therapy. NCT05633654 (ClinicalTrials.gov) Gilead Study ID: GS-US-595-6184 1 December 2022 12 December 2022 Recruiting.
PubMed: 38922307
DOI: 10.1080/14796694.2024.2357534 -
Scientific Reports Jun 2024The development of flame-retardant materials has become an important research direction. For the past dozen years, researchers have been exploring flame retardants with...
Preparation and characterization of novel flame-retardant paint of substituted cyclodiphosph(V)azane sulfonomide and their Cu(II), Cd(II) metal complexes as new additives for exterior wood coating protection.
The development of flame-retardant materials has become an important research direction. For the past dozen years, researchers have been exploring flame retardants with high flame-retardant efficiency, low toxicity, less smoke, or other excellent performance flame retardants. Therefore, this work aimed to synthesize new cyclodiphosph(V)azane derivatives and their Cu(II) and Cd(II) metal complexes and investigated their potential applications as high flame-retardant efficiency. Various techniques were used to characterize the prepared ligand HL and its metal complexes, including elemental analyses, mass spectra, conductivity measurements, electronic spectral data UV-vis, FT-IR, H,C-NMR, TGA, XRD, and molecular docking experiments studies were M. tuberculosis receptors (PDB ID: 5UHF) and the crystal structure of human topoisomerase II alpha (PDB ID: 4FM9). Wood-based paint was physically mixed with the ligand HL and its metal complexes. The obtained results of mechanical characteristics of the dried paint layers were noticed to improve, such as gloss value, which ranged from 85 to 95, hardness 1.5-2.5 kg, adhesion 4B to 5B, and impact resistance, which improved from 1.3 to 2.5 J. Moreover, the obtained results of flame-retardant properties showed a significant retardant impact compared to the blank sample, such as ignitability, which includes the heat flux which increased from 10 to 25 kW/m, and ignition time, ranging from 550 to 1200 s, respectively, and limiting oxygen index (LOI) (%) which has been increased from 21 to 130 compared with the plywood sample and sample blank. The ordering activity of the observed results was noticed that coated sample based on Cd(II) metal complexes > coated sample based on Cu(II) metal complexes of Cyclophosphazene ligand > coated sample based on phosphazene ligand HL > coated sample without additives > uncoated sample. This efficiency may be attributed to (1) the HL is an organophosphorus compound, which contains P, N, Cl, and aromatic six- and five-member ring, (2) Cu(II) and Cd(II) metal complexes characterized by high thermal stability, good stability, excellent performance flame retardants, and wide application.
PubMed: 38914569
DOI: 10.1038/s41598-024-64065-w -
Heliyon Jun 2024This research examines the function of protein associated with topoisomerase II homolog 1 () in nasal-type natural killer/T-cell lymphoma (NKTCL) and head and neck...
This research examines the function of protein associated with topoisomerase II homolog 1 () in nasal-type natural killer/T-cell lymphoma (NKTCL) and head and neck squamous cell carcinoma (HNSCC). We analyzed bulk RNA-seq data from NKTCL, nasal polyps, and normal nasal mucosa, identifying 439 differentially expressed genes. Machine learning algorithms highlighted as a hub gene. exhibited significant upregulation in NKTCL and HNSCC tumor samples in comparison to normal tissues, showing high diagnostic accuracy (AUC = 1.000) for NKTCL. Further analysis of local hospital data identified as an independent prognostic risk factor for NKTCL. Data analysis of TCGA and GEO datasets revealed that high expression correlated with poorer prognosis in HNSCC patients ( < 0.05). We also constructed a -based nomogram, which emerged as an independent prognostic predictor for HNSCC after addressing missing values. Additionally, we found a strong correlation between and various immune cell infiltrates (e.g., activated.CD4 T cell), and a significant association with the expression of 37 immune checkpoints genes (e.g., , ) and 20 N6-methyladenosine-related genes (e.g., , ) (all < 0.05). Both TCIA and TIDE algorithms suggested that could potentially predict immunotherapy efficacy ( < 0.05). Cellular experiments demonstrated that transfection with a silencing plasmid of significantly inhibited the malignant behaviors of SNK6 and FaDu cell lines( < 0.05). In conclusion, our findings suggest that may serve as a valuable prognostic and predictive biomarker in NKTCL and HNSCC, highlighting its significant role in these cancers.
PubMed: 38912458
DOI: 10.1016/j.heliyon.2024.e32158 -
Bioorganic & Medicinal Chemistry Jul 2024N-(Benzothiazole-2-yl)pyrrolamide DNA gyrase inhibitors with benzyl or phenethyl substituents attached to position 3 of the benzothiazole ring or to the carboxamide...
Exploring the interaction of N-(benzothiazol-2-yl)pyrrolamide DNA gyrase inhibitors with the GyrB ATP-binding site lipophilic floor: A medicinal chemistry and QTAIM study.
N-(Benzothiazole-2-yl)pyrrolamide DNA gyrase inhibitors with benzyl or phenethyl substituents attached to position 3 of the benzothiazole ring or to the carboxamide nitrogen atom were prepared and studied for their inhibition of Escherichia coli DNA gyrase by supercoiling assay. Compared to inhibitors bearing the substituents at position 4 of the benzothiazole ring, the inhibition was attenuated by moving the substituent to position 3 and further to the carboxamide nitrogen atom. A co-crystal structure of (Z)-3-benzyl-2-((4,5-dibromo-1H-pyrrole-2-carbonyl)imino)-2,3-dihydrobenzo[d]-thiazole-6-carboxylic acid (I) in complex with E. coli GyrB24 (ATPase subdomain) was solved, revealing the binding mode of this type of inhibitor to the ATP-binding pocket of the E. coli GyrB subunit. The key binding interactions were identified and their contribution to binding was rationalised by quantum theory of atoms in molecules (QTAIM) analysis. Our study shows that the benzyl or phenethyl substituents bound to the benzothiazole core interact with the lipophilic floor of the active site, which consists mainly of residues Gly101, Gly102, Lys103 and Ser108. Compounds with substituents at position 3 of the benzothiazole core were up to two orders of magnitude more effective than compounds with substituents at the carboxamide nitrogen. In addition, the 6-oxalylamino compounds were more potent inhibitors of E. coli DNA gyrase than the corresponding 6-acetamido analogues.
Topics: Topoisomerase II Inhibitors; DNA Gyrase; Binding Sites; Escherichia coli; Structure-Activity Relationship; Benzothiazoles; Adenosine Triphosphate; Molecular Structure; Quantum Theory; Anti-Bacterial Agents; Models, Molecular
PubMed: 38906068
DOI: 10.1016/j.bmc.2024.117798 -
Journal of Clinical Oncology : Official... Jun 2024SHR-A1811 is an antibody-drug conjugate composed of an anti-human epidermal growth factor receptor 2 (HER2) antibody trastuzumab, a cleavable linker, and a topoisomerase...
Safety, Efficacy, and Pharmacokinetics of SHR-A1811, a Human Epidermal Growth Factor Receptor 2-Directed Antibody-Drug Conjugate, in Human Epidermal Growth Factor Receptor 2-Expressing or Mutated Advanced Solid Tumors: A Global Phase I Trial.
PURPOSE
SHR-A1811 is an antibody-drug conjugate composed of an anti-human epidermal growth factor receptor 2 (HER2) antibody trastuzumab, a cleavable linker, and a topoisomerase I inhibitor payload. We assessed the safety, tolerability, antitumor activity, and pharmacokinetics of SHR-A1811 in heavily pretreated HER2-expressing or mutated advanced solid tumors.
METHODS
This global, multi-center, first-in-human, phase I trial was conducted at 33 centers. Patients who had HER2-expressing or mutated unresectable, advanced, or metastatic solid tumors and were refractory or intolerant to standard therapies were enrolled. SHR-A1811 was administered intravenously at doses ranging from 1.0 to 8.0 mg/kg once every 3 weeks. The primary end points were dose-limiting toxicity, safety, and the recommended phase II dose.
RESULTS
From September 7, 2020, to February 27, 2023, 307 patients who had undergone a median of three (IQR, 2-5) previous treatment regimens in the metastatic setting received SHR-A1811 treatment. As of data cutoff (February 28, 2023), one patient from the 6.4 mg/kg group experienced dose-limiting toxicities (pancytopenia and colitis). The most common grade 3 or higher adverse events (AEs) included decreased neutrophil count (119 [38.8%]) and decreased WBC count (70 [22.8%]). Interstitial lung disease occurred in only eight (2.6%) patients. Serious AEs and deaths occurred in 70 (22.8%) and 13 (4.2%) patients, respectively. SHR-A1811 led to objective responses in 59.9% (184/307) of all patients, 76.3% (90/118) of HER2-positive breast cancer, 60.4% (55/91) of HER2 low-expressing breast cancer, and 45.9% (39/85 with evaluable tumor responses) of the 98 nonbreast tumors.
CONCLUSION
SHR-A1811 exhibited acceptable tolerability, promising antitumor activity, and a favorable pharmacokinetic profile in heavily pretreated advanced solid tumors. The recommended phase II dose of 4.8 or 6.4 mg/kg was selected for various tumor types.
PubMed: 38900984
DOI: 10.1200/JCO.23.02044 -
International Journal of Molecular... May 2024DNA Topoisomerase IIα (Top2A) is a nuclear enzyme that is a cancer drug target, and there is interest in identifying novel sites on the enzyme to inhibit cancer cells...
DNA Topoisomerase IIα (Top2A) is a nuclear enzyme that is a cancer drug target, and there is interest in identifying novel sites on the enzyme to inhibit cancer cells more selectively and to reduce off-target toxicity. The C-terminal domain (CTD) is one potential target, but it is an intrinsically disordered domain, which prevents structural analysis. Therefore, we set out to analyze the sequence of Top2A from 105 species using bioinformatic analysis, including the PSICalc algorithm, Shannon entropy analysis, and other approaches. Our results demonstrate that large (10th-order) interdependent clusters are found including non-proximal positions across the major domains of Top2A. Further, CTD-specific clusters of the third, fourth, and fifth order, including positions that had been previously analyzed via mutation and biochemical assays, were identified. Some of these clusters coincided with positions that, when mutated, either increased or decreased relaxation activity. Finally, sites of low Shannon entropy (i.e., low variation in amino acids at a given site) were identified and mapped as key positions in the CTD. Included in the low-entropy sites are phosphorylation sites and charged positions. Together, these results help to build a clearer picture of the critical positions in the CTD and provide potential sites/regions for further analysis.
Topics: DNA Topoisomerases, Type II; Computational Biology; Humans; Protein Domains; Entropy; Amino Acid Sequence; Poly-ADP-Ribose Binding Proteins; Phosphorylation
PubMed: 38891861
DOI: 10.3390/ijms25115674 -
Nature Communications Jun 2024RNA Polymerase (RNAP) II transcription on non-coding repetitive satellite DNAs plays an important role in chromosome segregation, but a little is known about the...
RNA Polymerase (RNAP) II transcription on non-coding repetitive satellite DNAs plays an important role in chromosome segregation, but a little is known about the regulation of satellite transcription. We here show that Topoisomerase I (TopI), not TopII, promotes the transcription of α-satellite DNAs, the main type of satellite DNAs on human centromeres. Mechanistically, TopI localizes to centromeres, binds RNAP II and facilitates RNAP II elongation. Interestingly, in response to DNA double-stranded breaks (DSBs), α-satellite transcription is dramatically stimulated in a DNA damage checkpoint-independent but TopI-dependent manner, and these DSB-induced α-satellite RNAs form into strong speckles in the nucleus. Remarkably, TopI-dependent satellite transcription also exists in mouse 3T3 and Drosophila S2 cells and in Drosophila larval imaginal wing discs and tumor tissues. Altogether, our findings herein reveal an evolutionally conserved mechanism with TopI as a key player for the regulation of satellite transcription at both cellular and animal levels.
Topics: Animals; DNA, Satellite; Humans; Centromere; Mice; DNA Topoisomerases, Type I; Transcription, Genetic; RNA Polymerase II; DNA Breaks, Double-Stranded; Drosophila; Drosophila melanogaster; Evolution, Molecular
PubMed: 38886382
DOI: 10.1038/s41467-024-49567-5 -
Drug Delivery and Translational Research Jun 2024Doxorubicin is a key treatment for breast cancer, but its effectiveness often comes with significant side effects. Its actions include DNA intercalation, topoisomerase... (Review)
Review
Doxorubicin is a key treatment for breast cancer, but its effectiveness often comes with significant side effects. Its actions include DNA intercalation, topoisomerase II inhibition, and reactive oxygen species generation, leading to DNA damage and cell death. However, it can also cause heart problems and low blood cell counts. Current trials aim to improve doxorubicin therapy by adjusting doses, using different administration methods, and combining it with targeted treatments or immunotherapy. Nanoformulations show promise in enhancing doxorubicin's effectiveness by improving drug delivery, reducing side effects, and overcoming drug resistance. This review summarizes recent progress and difficulties in using doxorubicin for breast cancer, highlighting its mechanisms, side effects, ongoing trials, and the potential impact of nanoformulations. Understanding these different aspects is crucial in optimizing doxorubicin's use and improving outcomes for breast cancer patients. This review examines the toxicity of doxorubicin, a drug used in breast cancer treatment, and discusses strategies to mitigate adverse effects, such as cardioprotective agents and liposomal formulations. It also discusses clinical trials evaluating doxorubicin-based regimens, the evolving landscape of combination therapies, and the potential of nanoformulations to optimize delivery and reduce systemic toxicity. The review also discusses the potential of liposomes, nanoparticles, and polymeric micelles to enhance drug accumulation within tumor tissues while sparing healthy organs.
PubMed: 38884850
DOI: 10.1007/s13346-024-01648-0 -
Archiv Der Pharmazie Jun 2024A series of tetrahydrobenzo[b]thiophene derivatives was designed and synthesized as dual topoisomerase (Topo) I/II inhibitors implicating potential DNA intercalation....
Pharmacophore-based, rationale design, and efficient synthesis of novel tetrahydrobenzo[b]thiophene candidates as potential dual Topo I/II inhibitors and DNA intercalators.
A series of tetrahydrobenzo[b]thiophene derivatives was designed and synthesized as dual topoisomerase (Topo) I/II inhibitors implicating potential DNA intercalation. Ethyl-2-amino-3-cyano-4,5,6,7-tetrahydrobenzo[b]thiophene-4-carboxylate (1) was prepared by modification of the Gewald reaction procedure using a FeO nanocatalyst and then it was used as a building block for the synthesis of tetrahydrobenzo[b]thiophene candidates (2-14). Interestingly, compound 14 showed the best cytotoxic potential against hepatocellular, colorectal, and breast cancer cell lines (IC = 7.79, 8.10, and 3.53 µM), respectively, surpassing doxorubicin at breast cancer (IC = 4.17 µM). Meanwhile, the Topo I and II inhibition assay displayed that compound 3 could exhibit the best inhibitory potential among the investigated candidates (IC = 25.26 and 10.01 nM), respectively, in comparison to camptothecin (IC = 28.34 nM) and doxorubicin (IC = 11.01 nM), as reference standards. In addition, the DNA intercalation assay showed that compound 14 could display the best binding affinity with an IC value of 77.82 µM in comparison to doxorubicin (IC = 58.03 µM). Furthermore, cell cycle and apoptosis analyses described that compound 3 prompts the G1 phase arrest in michigan cancer foundation-7 cancer cells and increases the apoptosis ratio by 29.31% with respect to untreated cells (2.25%). Additionally, the conducted molecular docking assured the promising binding of the investigated members toward Topo I and II with potential DNA intercalation. Accordingly, the synthesized compounds could be treated as promising anticancer candidates for future optimization.
PubMed: 38864845
DOI: 10.1002/ardp.202400217