High-grade serous ovarian cancer often responds well to the chemotherapy drug carboplatin, but why it so frequently comes back after treatment has been a medical mystery. Now a team of researchers has discovered that a subset of tumor cells that don’t produce the protein CA125, a biomarker used to test for ovarian cancer, has an enhanced ability to repair their DNA and resist programmed cell death — which allows the cells to evade the drug and live long enough to regrow the original tumor.
