TY - JOUR
T1 - Endogenous base damage as a driver of genomic instability in homologous recombination-deficient cancers
AU - Aubuchon, Lindsey N.
AU - Verma, Priyanka
N1 - Publisher Copyright:
© 2024 The Authors
PY - 2024/9
Y1 - 2024/9
N2 - Homologous recombination (HR) is a high-fidelity DNA double-strand break (DSB) repair pathway. Both familial and somatic loss of function mutation(s) in various HR genes predispose to a variety of cancer types, underscoring the importance of error-free repair of DSBs in human physiology. While environmental sources of DSBs have been known, more recent studies have begun to uncover the role of endogenous base damage in leading to these breaks. Base damage repair intermediates often consist of single-strand breaks, which if left unrepaired, can lead to DSBs as the replication fork encounters these lesions. This review summarizes various sources of endogenous base damage and how these lesions are repaired. We highlight how conversion of base repair intermediates, particularly those with 5′or 3′ blocked ends, to DSBs can be a predominant source of genomic instability in HR-deficient cancers. We also discuss how endogenous base damage and ensuing DSBs can be exploited to enhance the efficacy of Poly (ADP-ribose) polymerase inhibitors (PARPi), that are widely used in the clinics for the regimen of HR-deficient cancers.
AB - Homologous recombination (HR) is a high-fidelity DNA double-strand break (DSB) repair pathway. Both familial and somatic loss of function mutation(s) in various HR genes predispose to a variety of cancer types, underscoring the importance of error-free repair of DSBs in human physiology. While environmental sources of DSBs have been known, more recent studies have begun to uncover the role of endogenous base damage in leading to these breaks. Base damage repair intermediates often consist of single-strand breaks, which if left unrepaired, can lead to DSBs as the replication fork encounters these lesions. This review summarizes various sources of endogenous base damage and how these lesions are repaired. We highlight how conversion of base repair intermediates, particularly those with 5′or 3′ blocked ends, to DSBs can be a predominant source of genomic instability in HR-deficient cancers. We also discuss how endogenous base damage and ensuing DSBs can be exploited to enhance the efficacy of Poly (ADP-ribose) polymerase inhibitors (PARPi), that are widely used in the clinics for the regimen of HR-deficient cancers.
KW - Base damage
KW - BRCA1/2
KW - Fork collapse
KW - Homologous recombination
KW - PARP inhibitor
UR - http://www.scopus.com/inward/record.url?scp=85200126183&partnerID=8YFLogxK
U2 - 10.1016/j.dnarep.2024.103736
DO - 10.1016/j.dnarep.2024.103736
M3 - Article
C2 - 39096699
AN - SCOPUS:85200126183
SN - 1568-7864
VL - 141
JO - DNA Repair
JF - DNA Repair
M1 - 103736
ER -