The Role of chk2 in Response to DNA Damage in Cancer Cells

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, apoptosis, and chromatin restructuring. Checkpoint kinase 2 (chk2) is activated in response to DNA lesions. ATM phosphorylates chk2. The activated Chk2 kinase can phosphorylate the substrates, including the Brca1, E2F-1, PML, p53, and Cdc25 phosphatases, which has been associated with DNA repair, cell cycle arrest or induction of apoptosis. However, Chk2 is a tumor suppressor gene that maintains genomic integrity and it has been suggested as an anticancer therapy target.