Scientists from KAIST have developed a drug that is injected directly into the tumor and acts directly in the tumor environment. This drug is absorbed by immune cells called macrophages, which normally behave passively in the tumor. After absorbing the drug, macrophages are reprogrammed to recognize and actively attack cancer cells. At the same time, they can also activate other nearby components of the immune system, which strengthens the overall anti-tumor defense. The advantage of the approach is that it does not require the collection of immune cells from the body and their modification in the laboratory. In animal model studies, this strategy significantly slowed tumor growth. At the same time, it induced strong anti-cancer immune reactions in the tested animals.