All cells use sugar as a vital source of energy and building blocks. Unfortunately, that means even cancer cells use sugar. Researchers at Memorial Sloan Kettering (MSK) Cancer Center wondered what happens when tumor cells and immune cells battle for the same sugar supply. Using mouse models and data from human patients, the researchers found a direct relationship between the amount of sugar that a tumor consumes and the effectiveness of immunotherapy. The more sugar the tumor consumed, the less effective the immunotherapy.