title: Mechanisms of oncogenic chromosomal translocations.
abstract: Chromosome translocations are caused by inappropriate religation of two DNA double-strand breaks (DSBs) in heterologous chromosomes. These DSBs can be generated by endogenous or exogenous sources. Endogenous sources of DSBs leading to translocations include inappropriate recombination activating gene (RAG) or activation-induced deaminase (AID) activity during immune receptor maturation. Endogenous DSBs can also occur at noncanonical DNA structures or at collapsed replication forks. Exogenous sources of DSBs leading to translocations include ionizing radiation (IR) and cancer chemotherapy. Spatial proximity of the heterologous chromosomes is also important for translocations. While three distinct pathways for DNA DSB repair exist, mounting evidence supports alternative nonhomologous end joining (aNHEJ) as the predominant pathway through which the majority of translocations occur. Initiated by poly (ADP-ribose) polymerase 1 (PARP1), aNHEJ is utilized less frequently in DNA DSB repair than other forms of DSB repair. We recently found that PARP1 is essential for chromosomal translocations to occur and that small molecule PARP1 inhibitors, already in clinical use, can inhibit translocations generated by IR or topoisomerase II inhibition. These data confirm the central role of PARP1 in aNHEJ-mediated chromosomal translocations and raise the possibility of using clinically available PARP1 inhibitors in patients who are at high risk for secondary oncogenic chromosomal translocations.
authors: Department of Medicine, University of Florida College of Medicine, Gainesville, Florida.
authors: Michael
authors: M
authors: Byrne
authors: Justin
authors: J
authors: Wray
authors: Brian
authors: B
authors: Reinert
authors: Yuehan
authors: Y
authors: Wu
authors: Jac
authors: J
authors: Nickoloff
authors: Suk-Hee
authors: SH
authors: Lee
authors: Robert
authors: R
authors: Hromas
authors: Elizabeth
authors: E
authors: Williamson
mesh_terms: D000818:Animals; D002471:Cell Transformation, Neoplastic / Q000235:genetics*; D053903:DNA Breaks, Double-Stranded; D059766:DNA End-Joining Repair / Q000502:physiology; D004260:DNA Repair / Q000502:physiology; D003851:Deoxyribonucleases / Q000235:genetics; D006801:Humans; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases / Q000235:genetics / Q000502:physiology*; D011971:Receptors, Immunologic / Q000235:genetics; D014178:Translocation, Genetic / Q000235:genetics*
chemical_list: D011971:Receptors, Immunologic; C499320:PARP1 protein, human; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases; D003851:Deoxyribonucleases
keywords: DNA end-joining repair; DNA repair; chromosomal translocation; oncogenesis