DNA Damage Repair Pathway and Tumorigenesis & Therapy

Jiadong Wang School of Basic Medical Science Peking University Health Science Center

2019/12/3 1 2019/12/3 2 2019/12/3 Cancer Research 2005 3 ？ How does DNA Damage Repair Pathway Affect Genomic Stability?

？ How does DNA Damage Repair Pathway Affect Tumor Therapy?

Diseases related with DNA double strand break repair pathways

SCID: Severe Combine Immune Deficiency Cancer Prone: BRCA1/2 Familial breast cancer DNA-PK—SCID Neurodegeneration Artemis—RS-SCID

NHEJ mediated VDJ rearrangement The DNA double strand break repair pathways

Non-homologous end-joining G1 phase S/G2 phase

Damage Recognition

DNA end processing

Blunt DNA end Over-hanged DNA end Strand invasion DNA synthesis & resolution

DNA Ligation  How DDR factors are regulated precisely? Cell Reports 2017 Molecular Cell 2013  HR and NHEJ repair pathway choice Cancer Research 2013  Identify new DDR factors Journal Biol Chem 2013 PARPi (Niraparib) treatment resulted in significantly longer progression- free survival than placebo in the HRD-positive Recurrent Ovarian Cancer

2016. New England Journal of Medicine

Kill Cancer Resistance SSB PARPi BRCA-

BRCA BRCA+ Mutated Cancer ？ 2019/12/3 12 Artemis activity is crucial for PARPi sensitivity of BRCA deficient cells

Genes & Dev 2014

Acetylation of 53BP1 regulates the balance of HR Nucleic Acids Res. 2018 and NHEJ and decides the resistance to PARPi Sensor Mediator Fixer Background

MRE11:Ataxia-Telangiectasia-like disorder (ATLD)

1.Neurodegeneration Disease 2. Ataxia ATM Ataxia-Telangiectasia (AT) 3. Normomorph MRE11 Ataxia-Telangiectasia-like disorder (ATLD) 4. Cancer/Genomic instability NBS1 Nijmegen breakage syndrome (NBS)

RAD50 NBS-like disorder (NBSLD)

17 MRN complex(MRE11//NBS1)

MRE11 nuclease forms a trimeric complex (MRN) with RAD50 and NBS1

Stracker TH, Petrini JH. 2011, Nat Rev Mol Cell Biol. 18 Homologous recombination

How is MRN tightly regulated to avoid inefficient repair or unspecific resection?

19 C1QBP modulates DNA damage response by regulating MRE11

2019/12/3 20 Molecular Cell，2019 TAP-MS:MRN/C1QBP

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2019/12/3 21 C1QBP : • First identify C1q interaction protein • Critical for ARF induced apoptosis • Important for mitochondrial translation • ATM substrate

C1qbp-null mice: • Embryonic lethality with a severe developmental defect • Impaired mitochondrial protein synthesis • Immunodeficiency C1QBP interacts with MRE11 and RAD50 in vivo

GST pull-down Co-IP In vivo

2019/12/3 23 C1QBP interacts with MRE11 and RAD50 in vitro

In vitro

2019/12/3 24 MRN complex vs MRC complex

2019/12/3 25 Sucrose gradient fraction indicated that a substantial portion of MRE11/Rad50 co-sediments with C1QBP

WT C1QBP KO

2019/12/3 26 C1QBP forms MRC complex with MRE11 and RAD50

Exclusive complex? C1QBP

MRC complex competing with MRN complex

2019/12/3 27 C1QBP inhibits MRE11 exonuclease activity

2019/12/3 28 C1QBP disrupted the binding ability of MRE11/Rad50 with dsDNA and MRE11 exonuclease activity

2019/12/3 29 C1QBP could disrupt the existed MRE11/Rad50/DNA complex

2019/12/3 30 C1QBP interacts with GAR domain of MRE11

GAR motif: Glycine Arginine Rich motif

2019/12/3 31 R572Q and R576Q dramatically reduced the interaction between MRE11 and C1QBP

32 2019/12/3 Loss of GAR motif totally disrupts the interaction between MRE11 and C1QBP

MST(microscale thermophoresis)

2019/12/3 33 DNA damage-induced MRE11 phosphorylation dismisses MRC complex

DNA damage

2019/12/3 34 C1QBP translocated to nuclear upon DNA damage

2019/12/3 35 C1QBP stabilizes MRE11 and RAD50 in vivo

2019/12/3 36 C1QBP prevents MRE11 and RAD50 degradation C1QBP prevents MRE11 to associate with chromatin

2019/12/3 37 Loss of C1QBP causes retarded recruitment of MRE11 to damaged chromatin

GFP-MRE11

2019/12/3 38 Loss of C1QBP causes DNA end resection defects

2019/12/3 39 Loss of C1QBP impair DNA repair capability

2019/12/3 40 C1QBP is required for maintaining stability

2019/12/3 41 Positive correlation between C1QBP and MRE11

2019/12/3 42 C1QBP knockout cells displayed hypersensitivity to IR/CPT/Olaparib

2019/12/3 43 Higher level of C1QBP are associated with poor prognosis

2019/12/3 44 C1QBP is a potential therapeutic target for cancer treatment 2019/12/3 46 Brushes: MRE11/RAD50 Container: C1QBP Acknowledgement

Peking University • Xiang Guo • Meimei Zhao • Ruoshi Yuan • Yongtai Bai • Siyu Li • Yundong Xiong • Nie Chen • Shiwei Li • Wanchang Liu • Zhanzhan Xu M.D. Anderson Cancer Center • Dr. Junjie Chen

48 Thank You for Your Attention!