Specially packaged DNA secreted by tumor cells can trigger an immune response that inhibits the metastatic spread of the tumor to the liver, according to a study led by researchers at Weill Cornell Medicine, Memorial Sloan Kettering Cancer Center and Korea’s Yonsei University. The discovery improves the scientific understanding of cancer progression and anticancer immunity, and could yield new clinical tools for assessing and reducing metastasis risk.
In the study, reported Dec. 3 in Nature Cancer, the researchers examined cancer cells’ secretion of short stretches of DNA packaged on tiny capsules called extracellular vesicles (EVs). All cells use EVs to secrete proteins, DNA and other molecules, and tumor cells are particularly active EV secreters. The biological functions of these EV-packaged molecules are still being explored, but in this case, the researchers discovered that in various cancer types, EV-DNA secreted by tumor cells works as a “danger” signal that activates an anti-tumor response in the liver, reducing the risk of liver metastasis.