A new ruthenium complex with a dppz-like ligand pyidppz, [Ru(bpy)2(pyidppz)](2+) (pyidppz = 2-(pyridine-2-yl)imidazo-[4,5-b]dipyrido-[3,2-a:2',3'-c]phenazine) has been synthesized and characterized by ES-MS, elemental analysis, (1)H NMR. Intercalative mode of the complex bound to calf thymus DNA has been supported by different spectroscopic methods and viscosity measurements. The introduction of phenazine unit may be one of the main reasons for the weak emission of Ru(II) complex in aqueous solution. Under irradiation, this complex can efficiently cleave DNA. And the photocleavage reaction of the complex is found to be inhibited in the presence of singlet oxygen scavenger. Topoisomerase inhibition and DNA strand passage assay demonstrated that [Ru(bpy)2(pyidppz)](2+) and its parent complex [Ru(bpy)2(pyip)](2+) (pyip = 2-(pyridine-2-yl)imidazo[4,5-f][1,10]phenanthroline) can act as efficient catalytic inhibitor of DNA topoisomerase I.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1007/s10895-015-1644-8 | DOI Listing |
Sci Rep
January 2025
Departamento Biología Experimental, Universidad de Jaén, Paraje Las Lagunillas S/N E23071, Jaén, Spain.
In this study, we investigate the G2 checkpoint activated by chromosome entanglements, the so-called Decatenation Checkpoint (DC), which can be activated by TOP2A catalytic inhibition. Specifically, we focus on the spontaneous ability of cells to bypass or override this checkpoint, referred to as checkpoint adaptation. Some factors involved in adapting to this checkpoint are p53 and MCPH1.
View Article and Find Full Text PDFRedox Biol
January 2025
University of Chicago, Department of Molecular Genetics and Cell Biology, 929 E. 57th Street, Chicago, IL, 60637, USA. Electronic address:
During its catalytic cycle, the homodimeric ATPase topoisomerase II alpha (TOP2A) cleaves double stranded DNA and remains covalently bound to 5' ends via tyrosine phosphodiester bonds. After passing a second, intact duplex through, TOP2A rejoins the break and releases from the DNA. Thereby, TOP2A can relieve strain accumulated during transcription, replication and chromatin remodeling and disentangle sister chromatids for mitosis.
View Article and Find Full Text PDFPharmaceuticals (Basel)
January 2025
Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Sohag University, Sohag 82524, Egypt.
Ciprofloxacin, a widely used second-generation fluoroquinolone for treating bacterial infections, has recently shown notable anticancer properties. This review explores progress in developing ciprofloxacin derivatives with anticancer properties, emphasizing key structural changes that improve their therapeutic effectiveness by modifying the basic group at position 7, the carboxylic acid group at position 3, or both. It further investigates the mechanisms by which these derivatives fight cancer, such as inducing apoptosis, arresting the cell cycle, inhibiting topoisomerase I and II, preventing tubulin polymerization, suppressing interleukin 6, blocking thymidine phosphorylase, inhibiting multidrug resistance proteins, and hindering angiogenesis.
View Article and Find Full Text PDFInt J Mol Sci
January 2025
Department of Pharmacy, College of Pharmacy, Research Institute for Drug Development, Pusan National University, Busan 46241, Republic of Korea.
Topoisomerase II inhibitors, particularly etoposide, have long been integral to the treatment of lung cancer, especially small cell lung cancer. This review comprehensively examines the mechanisms of action of etoposide, its clinical efficacy, and its role in current lung cancer treatment regimens. Etoposide exerts its anticancer effects by inducing DNA strand breaks through the inhibition of topoisomerase II, leading to cancer cell apoptosis.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
Department of Obstetrics, The First Hospital of China Medical University, Shenyang, China. Electronic address:
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!