Blocking surprising master regulator of immunity eradicates liver tumors in mice

Curious, the researchers turned to existing databases to confirm that elevated levels of EPO are correlated with poorer survival of people with cancers of the liver, kidney, breast, colon and skin. They then tinkered with the ability of the tumor cells to make EPO and were surprised at what happened in the animals’ liver tumors. From cold to hot They found that mutations that had led to the development of cold tumors instead caused hot tumors when the tumors were modified to be unable to make EPO. Conversely, hot tumors that had previously been successfully eradicated by the immune system thrived when they were engineered to make elevated levels of EPO. Further exhaustive research showed that, in cold tumors, the tumor cells make and secrete EPO, which binds to receptors on the surface of immune cells called macrophages. The macrophages then switch to an immunosuppressive role, shooing away cancer-killing T cells and tamping down their activity. The importance of this EPO-moderated ... Read full article.