The Ras activation contributes to radioresistance, but the mechanism is unclear. This article shows that the expression of the dominant-positive H-Ras increased the Ku80 level, which is one of the key enzymes involved in repairing dsDNA breaks (DSB). After exposing the cells to ionizing radiation and analyzing them using an electrophoretic mobility shift assay and pulsed-field gel electrophoresis, it was found that activated H-Ras expression in NIH3T3 cells increases the DNA-binding activity of Ku80 and increases the DSB repair activity. Ku80 small interfering RNA expression was shown to reduce the oncogenic H-Ras-mediated increase in the DSBs and suppress the oncogenic H-Ras-mediated resistance of the cells to gamma-ray irradiation, whereas Ku80 overexpression in the NIH3T3 cells significantly increased the radioresistance. These results suggest that the Ku80 expression induced by oncogenic H-Ras seems to play an important role in protecting cells against gamma-ray irradiation.
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http://dx.doi.org/10.1158/0008-5472.CAN-04-4065 | DOI Listing |
Int J Cell Biol
January 2025
Department of Biotechnology and Plant Breeding, Sari Agricultural Sciences and Natural Resources University (SANRU), Sari, Iran.
Radiation therapy is one of the most effective treatments for approximately 60% of patients with cancer. During radiation exposure, the overproduction of reactive oxygen species (ROS) disrupts the lipid layer of the membrane, leading to subsequent peroxide radical formation. Cimetidine (Cim) and famotidine (Fam) are histamine H2 receptor antagonists (H2 blocker), also known as peptic ulcer drugs, that exert radioprotective effects.
View Article and Find Full Text PDFAging (Albany NY)
January 2025
Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC 20057, USA.
Exposure to ionizing radiation (IR), both low-LET (e.g., X-rays, γ rays) and high-LET (e.
View Article and Find Full Text PDFCarbohydr Polym
March 2025
College of Biological Science and Medical Engineering, Shanghai Engineering Research Center of Nano-Biomaterials and Regenerative Medicine, Donghua University, Shanghai 201620, PR China. Electronic address:
In this work we present a near-infrared (NIR)-operated nanoswitch based on chitosan nanoparticles (EpCAM-CS-co-PNVCL@IR780/IMQ NPs) that induces cascade immunogenic tumor ferroptosis via cytokine storm. The formulation was prepared by loading a photosensitiser (IR780) and an immunotherapeutic drug (imiquimod; IMQ) into temperature- and pH-responsive chitosan-based NPs functionalized with tumor-targeting aptamers. The EpCAM aptamer can chaperone the NPs selectively into cancer cells, and allow them to enter the cell nucleus.
View Article and Find Full Text PDFPhys Med Biol
January 2025
Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology (QST), 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan.
Anal Chem
January 2025
Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, Hunan Provincial University Key Laboratory for Environmental and Ecological Health, College of Chemistry, Xiangtan University, Xiangtan 411105, P.R. China.
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