DNA repair is critical to resolve extrinsic or intrinsic DNA damage to ensure regulated gene transcription and DNA replication. These pathways control repair of double strand breaks, interstrand crosslinks, and nucleotide lesions occurring on single strands. Distinct DNA repair pathways are highly inter-linked for the fast and optimal DNA repair. A deregulation of DNA repair pathways may mainta...

a better understanding of the mechanism of chromosomal aberration formation could be obtained by using dna repair inhibitors. immortalized normal human (mrc 5 svi) and ataxia telangiectasia ( at 5 biv a ) fibroblastic cell lines were treated with adenosine arabinoside (ara-a) and cytosine arabinoside (ara-c), both potent inhibitors of dna dsb repair, alone or in combination with x-rays at g2 or...

Drugs targeting DNA damage repair (DDR) pathways are exciting new agents in cancer therapy. Many of these drugs exhibit synthetic lethality with defects in DNA repair in cancer cells. For example, ovarian cancers with impaired homologous recombination DNA repair show increased sensitivity to poly(ADP-ribose) polymerase (PARP) inhibitors. Understanding the activity of different DNA repair pathwa...

DNA is constantly damaged by various endogenous and exogenous events. Repair systems constantly scan the genome for DNA lesions and replace damaged and mismatched bases, which finally enables the complex DNA double strand to store genetic information. This year's Nobel Prize in Chemistry was awarded to pioneers in this field, T. Lindahl, P. Modrich, and A. Sancar.

Abstract Substantial evidence has shown that overexpression of the inhibitor apoptosis protein (IAP) survivin in human tumors correlates significantly with treatment resistance and poor patient prognosis. Survivin serves as a radiation factor impacts DNA damage response by interacting DNA-dependent kinase (DNA-PKcs). However, complexity, molecular determinants, functional consequences this inte...

Chromatin is a highly dynamic structure regulated by different factors, such as ATPdependent remodeling complexes, incorporation of histone variants, post-translational modifications, and histones chaperones. During the DNA damage response, the chromatin architecture must be transiently and locally modified in order to regulate access to the DNA lesion. Chromatin remodeling at double-strand bre...

Accumulation of gene changes and chromosomal instability in response to cellular DNA damage lead to cancer. DNA damage induces cell cycle checkpoints pathways. Checkpoints regulate DNA replication and cell cycle progression, chromatin restructuring, and apoptosis. Checkpoint kinase 2 (chk2) is activated in response to DNA lesions. ATM phosphorylate chk2. The activated Chk2 kinase can phosphoryl...

DNA is subjected to many endogenous and exogenous damages. All organisms have developed a complex network of DNA repair mechanisms. A variety of different DNA repair pathways have been reported: direct reversal, base excision repair, nucleotide excision repair, mismatch repair, and recombination repair pathways. Recent studies of the fundamental mechanisms for DNA repair processes have revealed...

Objective: In this paper, we have introduced topoisomerase inhibitors, mechanism of action and types of them. DNA topoisomerases are ubiquitous enzymes that catalyze essential enzymes to solve the topological problems accompanying key nuclear processes such as DNA replication, transcription, repair and chromatin assembly by introducing temporary single or double strand breaks in the DNA. Result...