Prostate cancer is often resistant to immunotherapy, which harnesses a person’s immune system to recognize and destroy tumors. But a new technology that targets RNA in cancer cells gave immunotherapy new life, improving its ability to unleash cancer-killing cells in laboratory studies.

Most prostate tumors are dubbed “immune cold” because they don’t attract T cells (a type of immune cell) to the tumor. Using a CRISPR-based tool, researchers altered RNA to make the cancer cells more like magnets for T cells, allowing them to draw in and use the antitumor cells to destroy the cancer.

Published in Nature Biomedical Engineering, the study found the technology made prostate tumors more responsive to immune checkpoint therapy in mice, increasing the number of immune cells that infiltrated the tumor and subsequently destroyed cancerous cells.