Mechanisms of the BRCA-network in tumorigenesis and therapeutic response

Mechanisms of the BRCA-network in Tumorigenesis and Therapeutic Response (OVERALL) Abstract: The faithful repair of DNA damage and efficient resolution of stalled replication forks are fundamental mechanisms by which mammalian cells maintain DNA sequence fidelity and chromosomal integrity during DNA

replication and in response to exogenous DNA damage. Defects in DNA repair mechanisms not only contribute to genomic instability and subsequent tumorigenesis, but also can alter the epigenetic landscape of cells and

impart therapeutic vulnerabilities that can be exploited clinically. The investigators participating in this P01 project share common interests in understanding the mechanisms by which cells maintain genomic integrity to suppress tumorigenesis, and in exposing tumor vulnerability to therapy based on mechanistic understandings of the

genomic consequences of impaired DNA repair. One particularly strong area of research offered by this team is a multi-disciplinary approach to understanding the basic mechanisms by which the BRCA1-PALB2-BRCA2 complex and associated regulators participate in regulating DNA replication and repair choice. Regulators of the

BRCA-network include, 53BP1, RNF4, BARD1, TOPBP1, EHMT2 (G9a), MCM10, SLFN11 (mouse Slfn9), and BCCIP. Some of these factors have been a long-standing research focus for investigators in the project team. The research collaboration is formed around the central themes of how members of this large network of proteins

interface with each other to maintain genome integrity, suppress tumor development and modulate tumor response to cancer therapy. Four projects, two Shared Resource Cores, and an Administrative Core are proposed to achieve three scientific goals: 1) to reveal novel mechanisms by which the recruitment and function

of the BRCA1-PALB2-BRCA2 network is regulated by chromatin context mediated by methylation, sumoylation, and ubiquitination; 2) to refine the roles of the BRCA network in DNA replication, tumor suppression and define the genomic consequences of BRCA dysfunction; and 3) to explore new opportunities to target defects in the

BRCA network for therapeutics in medulloblastoma and breast cancer.