The dominant role of non-homologous end-joining in the repair of radiation-induced double-strand breaks identifies DNA-dependent protein kinase (DNA-PK) as an excellent target for the development of radiosensitizers. We report the discovery of a new class of imidazo[4,5-]pyridine-2-one DNA-PK inhibitors. Structure-activity studies culminated in the identification of as a nM DNA-PK inhibitor with excellent selectivity for DNA-PK compared to related phosphoinositide 3-kinase (PI3K) and PI3K-like kinase (PIKK) families and the broader kinome, and displayed DNA-PK-dependent radiosensitization of HAP1 cells. Compound demonstrated robust radiosensitization of a broad range of cancer cells , displayed high oral bioavailability, and sensitized colorectal carcinoma (HCT116/54C) and head and neck squamous cell carcinoma (UT-SCC-74B) tumor xenografts to radiation. Compound also provided substantial tumor growth inhibition of HCT116/54C tumor xenografts in combination with radiation. Compound represents a new, potent, and selective class of DNA-PK inhibitors with significant potential as radiosensitizers for cancer treatment.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC11284801PMC
http://dx.doi.org/10.1021/acs.jmedchem.4c01120DOI Listing

Publication Analysis

Top Keywords

dna-dependent protein
8
protein kinase
8
dna-pk inhibitors
8
tumor xenografts
8
radiation compound
8
dna-pk
5
identification 6-anilino
4
6-anilino imidazo[45-]pyridin-2-ones
4
imidazo[45-]pyridin-2-ones selective
4
selective dna-dependent
4

Similar Publications

Exposure to reactive oxygen species (ROS) can induce DNA-protein crosslinks (DPCs), unusually bulky DNA lesions that block replication and transcription and play a role in aging, cancer, cardiovascular disease, and neurodegenerative disorders. Repair of DPCs depends on the coordinated efforts of proteases and DNA repair enzymes to cleave the protein component of the lesion to smaller DNA-peptide crosslinks which can be processed by tyrosyl-DNA phosphodiesterases 1 and 2, nucleotide excision and homologous recombination repair pathways. DNA-dependent metalloprotease SPRTN plays a role in DPC repair, and SPRTN-deficient mice exhibit an accelerated aging phenotype and develop liver cancer early in life.

View Article and Find Full Text PDF

Advances in fundus imaging are revealing disruptions in the neurovascular unit in diabetic retinopathy (DR). In the era of anti-VEGF treatment, a thorough characterization of neurodegeneration is imperative until DR patients are sufficiently cured. Here we demonstrate that extracellular mitochondria exacerbate retinal pigment epithelium (RPE) degeneration and inflammation in DR.

View Article and Find Full Text PDF

DNA Ligase I Circularises Potato Spindle Tuber Viroid RNA in a Biomolecular Condensate.

Mol Plant Pathol

December 2024

Plant Molecular and Cell Biology Program, University of Florida, Gainesville, Florida, USA.

Viroids are single-stranded circular noncoding RNAs that mainly infect crops. Upon infection, nuclear-replicating viroids engage host DNA-dependent RNA polymerase II for RNA-templated transcription, which is facilitated by a host protein TFIIIA-7ZF. The sense-strand and minus-strand RNA intermediates are differentially localised to the nucleolus and nucleoplasm regions, respectively.

View Article and Find Full Text PDF

The N-degron pathway mediates the autophagic degradation of cytosolic mitochondrial DNA during sterile innate immune responses.

Cell Rep

December 2024

Cellular Degradation Biology Center and Department of Biomedical Sciences, College of Medicine, Seoul National University, Seoul 03080, Republic of Korea; Convergence Research Center for Dementia, Seoul National University Medical Research Center, Seoul 110-799, Republic of Korea; AUTOTAC Bio, Inc., Changkkyunggung-ro 254, Jongno-gu, Seoul 03077, Republic of Korea; Ischemic/Hypoxic Disease Institute, College of Medicine, Seoul National University, Seoul 110-799, Republic of Korea. Electronic address:

The human body reacts to tissue damage by generating damage-associated molecular patterns (DAMPs) that activate sterile immune responses. To date, little is known about how DAMPs are removed to avoid excessive immune responses. Here, we show that proteasomal dysfunction induces the release of mitochondrial DNA (mtDNA) as a DAMP that activates the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon gene (STING) pathway and is subsequently degraded through the N-degron pathway.

View Article and Find Full Text PDF

[Methods to Increase the Efficiency of Knock-in of a Construct Encoding the HIV-1 Fusion Inhibitor, MT-C34 Peptide, into the CXCR4 Locus in the CEM/R5 T Cell Line].

Mol Biol (Mosk)

December 2024

Center of Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology, Russian Academy of Sciences, Moscow, 119334 Russia.

The low knock-in efficiency, especially in primary human cells, limits the use of the genome editing technology for therapeutic purposes, rendering it important to develop approaches for increasing the knock-in levels. In this work, the efficiencies of several approaches were studied using a model of knock-in of a construct coding for the peptide HIV fusion inhibitor MT-C34 into the human CXCR4 locus in the CEM/R5 T cell line. First, donor DNA modification was evaluated as a means to improve the efficiency of plasmid transport into the nucleus.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!