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Depletion of Akt1 and Akt2 Impairs the Repair of Radiation-Induced DNA Double Strand Breaks via Homologous Recombination

Homologous recombination repair (HRR), non-homologous end-joining (NHEJ) and alternative NHEJ are major pathways that are utilized by cells for processing DNA double strand breaks (DNA-DSBs); their function plays an important role in the radiation resistance of tumor cells. Conflicting data exist re...

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Autores principales: Mohammadian Gol, Tahereh, Rodemann, H. Peter, Dittmann, Klaus
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2019
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6941063/
https://www.ncbi.nlm.nih.gov/pubmed/31847370
http://dx.doi.org/10.3390/ijms20246316
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author Mohammadian Gol, Tahereh
Rodemann, H. Peter
Dittmann, Klaus
author_facet Mohammadian Gol, Tahereh
Rodemann, H. Peter
Dittmann, Klaus
author_sort Mohammadian Gol, Tahereh
collection PubMed
description Homologous recombination repair (HRR), non-homologous end-joining (NHEJ) and alternative NHEJ are major pathways that are utilized by cells for processing DNA double strand breaks (DNA-DSBs); their function plays an important role in the radiation resistance of tumor cells. Conflicting data exist regarding the role of Akt in homologous recombination (HR), i.e., the regulation of Rad51 as a major protein of this pathway. This study was designed to investigate the specific involvement of Akt isoforms in HRR. HCT116 colon cancer cells with stable AKT-knock-out and siRNA-mediated AKT-knockdown phenotypes were used to investigate the role of Akt1 and Akt2 isoforms in HR. The results clearly demonstrated that HCT116 AKT1-KO and AKT2-KO cells have a significantly reduced Rad51 foci formation 6 h post irradiation versus parental cells. Depletion of Akt1 and Akt2 protein levels as well as inhibition of Akt kinase activity resulted in an increased number of residual-γH2AX in CENP-F positive cells mainly representing the S and G2 phase cells. Furthermore, inhibition of NHEJ and HR using DNA-PK and Rad51 antagonists resulted in stronger radiosensitivity of AKT1 and AKT2 knockout cells versus wild type cells. These data collectively show that both Akt1 and Akt2 are involved in DSBs repair through HRR.
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spelling pubmed-69410632020-01-09 Depletion of Akt1 and Akt2 Impairs the Repair of Radiation-Induced DNA Double Strand Breaks via Homologous Recombination Mohammadian Gol, Tahereh Rodemann, H. Peter Dittmann, Klaus Int J Mol Sci Article Homologous recombination repair (HRR), non-homologous end-joining (NHEJ) and alternative NHEJ are major pathways that are utilized by cells for processing DNA double strand breaks (DNA-DSBs); their function plays an important role in the radiation resistance of tumor cells. Conflicting data exist regarding the role of Akt in homologous recombination (HR), i.e., the regulation of Rad51 as a major protein of this pathway. This study was designed to investigate the specific involvement of Akt isoforms in HRR. HCT116 colon cancer cells with stable AKT-knock-out and siRNA-mediated AKT-knockdown phenotypes were used to investigate the role of Akt1 and Akt2 isoforms in HR. The results clearly demonstrated that HCT116 AKT1-KO and AKT2-KO cells have a significantly reduced Rad51 foci formation 6 h post irradiation versus parental cells. Depletion of Akt1 and Akt2 protein levels as well as inhibition of Akt kinase activity resulted in an increased number of residual-γH2AX in CENP-F positive cells mainly representing the S and G2 phase cells. Furthermore, inhibition of NHEJ and HR using DNA-PK and Rad51 antagonists resulted in stronger radiosensitivity of AKT1 and AKT2 knockout cells versus wild type cells. These data collectively show that both Akt1 and Akt2 are involved in DSBs repair through HRR. MDPI 2019-12-14 /pmc/articles/PMC6941063/ /pubmed/31847370 http://dx.doi.org/10.3390/ijms20246316 Text en © 2019 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Mohammadian Gol, Tahereh
Rodemann, H. Peter
Dittmann, Klaus
Depletion of Akt1 and Akt2 Impairs the Repair of Radiation-Induced DNA Double Strand Breaks via Homologous Recombination
title Depletion of Akt1 and Akt2 Impairs the Repair of Radiation-Induced DNA Double Strand Breaks via Homologous Recombination
title_full Depletion of Akt1 and Akt2 Impairs the Repair of Radiation-Induced DNA Double Strand Breaks via Homologous Recombination
title_fullStr Depletion of Akt1 and Akt2 Impairs the Repair of Radiation-Induced DNA Double Strand Breaks via Homologous Recombination
title_full_unstemmed Depletion of Akt1 and Akt2 Impairs the Repair of Radiation-Induced DNA Double Strand Breaks via Homologous Recombination
title_short Depletion of Akt1 and Akt2 Impairs the Repair of Radiation-Induced DNA Double Strand Breaks via Homologous Recombination
title_sort depletion of akt1 and akt2 impairs the repair of radiation-induced dna double strand breaks via homologous recombination
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6941063/
https://www.ncbi.nlm.nih.gov/pubmed/31847370
http://dx.doi.org/10.3390/ijms20246316
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