By blocking protein, researchers keep brain tumors from repairing themselves

Researchers at the San Diego branch of the Ludwig Institute for Cancer Research at University of California San Diego, with colleagues around the country, report that inhibiting activity of a specific protein in glioblastomas (GBM) boosts their sensitivity to radiation, thus improving treatment prospects for one of the most common and aggressive forms of brain cancer. The findings are published on February 28, 2019, the online issue of Cancer Cell. GBM are extremely difficult to treat, with a median survival rate of 15 to 16 months, meaning that half of all patients survive to this length of time. Radiation and chemotherapy are the standard-of-care treatments, both intended to damage and destroy DNA in cancer cells, but their efficiency declines as tumors develop therapeutic resistance. In their new paper, senior author Frank B. Furnari, Ph.D., professor of pathology at UC San Diego School of Medicine and member of Ludwig San Diego, first author Jianhui Ma, Ph.D., a postdoctoral fellow, and colleagues identified a mechanism used by GBM to promote therapeutic resistance: phosphorylation of a protein called phosphatase and tensin homolog or PTEN, which is encoded by the PTEN gene.