These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Inhibition of homologous recombination by hyperthermia shunts early double strand break repair to non-homologous end-joining.
    Author: Bergs JW, Krawczyk PM, Borovski T, ten Cate R, Rodermond HM, Stap J, Medema JP, Haveman J, Essers J, van Bree C, Stalpers LJ, Kanaar R, Aten JA, Franken NA.
    Journal: DNA Repair (Amst); 2013 Jan 01; 12(1):38-45. PubMed ID: 23237939.
    Abstract:
    In S and G2 phase mammalian cells DNA double strand breaks (DSBs) can potentially be repaired by homologous recombination (HR) or non-homologous end-joining (NHEJ). Results of several studies suggest that these two mechanistically distinct repair pathways can compete for DNA ends. Because HR and NHEJ differ with respect to error susceptibility, generation of chromosome rearrangements, which are potentially carcinogenic products of DSB repair, may depend on the pathway choice. To investigate this hypothesis, the influence of HR and NHEJ inhibition on the frequencies of chromosome aberrations in G2 phase cells was investigated. SW-1573 and RKO cells were treated with mild (41 °C) hyperthermia in order to disable HR and/or NU7441/cisplatin to inactivate NHEJ and frequencies of chromosomal fragments (resulting from unrepaired DSBs) and translocations (products of erroneous DSB rejoining) were studied using premature chromosome condensation (PCC) combined with fluorescence in situ hybridization (FISH). It is shown here that temporary inhibition of HR by hyperthermia results in increased frequency of ionizing-radiation (IR)-induced chromosomal translocations and that this effect is abrogated by NU7441- or cisplatin-mediated inhibition of NHEJ. The results suggest that in the absence of HR, DSB repair is shifted to the error-prone NHEJ pathway resulting in increased frequencies of chromosomal rearrangements. These results might be of consequence for clinical cancer treatment approaches that aim at inhibition of one or more DSB repair pathways.
    [Abstract] [Full Text] [Related] [New Search]