This disclosure relates to methods of identifying subjects that have an increased likelihood of responding to a combination of a poly (ADP) ribose polymerase enzyme inhibitor and a platinum based reagent and optionally other anticancer agents in the course of chemotherapy. In certain embodiments, the disclosure relates to methods of treating cancer comprising administering an effective amount of a poly (ADP) ribose polymerase enzyme inhibitor and a platinum based reagent to the subject in need thereof, wherein the subject is in need thereof because measuring a quantity of RNA isolated from a cancer cell from the subject indicates an increased quantity of the RNA compared to a normal sample, wherein the RNA is associated with one or more of the following genes/pseudogenes GLS, UBEC2, HACL1, MSI2, and LOC100129585.
