Patients suffering from ovarian cancer, whose cancers are known to have mutated BRCA genes, can be treated with drugs known as PARP inhibitors. Unfortunately, not every patient responds to this treatment. RRCancer Researchers Drs. A-M Mes-Masson, D. Provencher, and P. Tonin compared different ovarian cancer cells to study the variances in cells that did and did not respond to treatment. BRCA and PARP are already known to be associated with the cell’s mechanisms to repair damage to DNA. Repairing DNA in a cell is a complicated process that involves many different components and pathways. After studying the cell lines, researchers found that the cell lines with defects in more than one DNA repair pathway were most susceptible to PARP inhibitors. In the future, cancer patients can have a genetic screening that may be able to indicate how well they will respond to this type of treatment.