Conventional cancer therapies target the characteristics of uncontrolled growth of cancer cells. Due to high level of DNA replication DNA damage compromising or inhibiting DNA replication can trigger cell death. However, cell death is also triggered in healthy tissues, causing dose-limiting side effects. Thus, many efforts are focused on developing cancer therapies that selectively kill cancer cells without adversely affecting healthy tissues. The concept of ‘synthetic lethality’ refers to the cell-lethal effects of the combined inactivation of two genetically distinct pathways. In a cancer setting, synthetic lethality provides a conceptual framework for the development of drugs that are selectively toxic in specific genetic backgrounds associated with tumors. One example is the synthetic lethality of PARP inhibition in tumors carrying mutations in brca1 or brca2. It is likely that other examples of DNA repair-associated synthetic lethal relationships relevant to cancer exist.
We are focusing on small molecules and genome editing strategies that target cancer cells more specifically based on unique genomic features. We will use them as probes to study DNA repair mechanisms and to evaluate their therapeutic potential for cancer treatment.