Ellen Ackerstaff1, Brij B. Patel2, Yanique I. Rattigan2, Natalia Kruchevsky1, John W. Glod2, George Sukenick1, Jason A. Koutcher1, Debabrata Banerjee2
1Memorial Sloan Kettering Cancer Center, New York, NY, United States; 2The Cancer Institute of New Jersey, RWJMS, UMDNJ, New Brunswick, NJ, United States
Previously, we have shown that cancer-associated fibroblasts (CAFs) take up and metabolize lactate. Here, we hypothesize that breast cancer cells and stromal cells have lactate-mediated metabolic coupling similar to muscle cells, where glycolytic muscle cells secrete lactate that is used by neighboring, oxidative muscle cells as an energy source. Our 13C MRS studies indicate that lactate-metabolizing CAFs secrete 13C-labeled pyruvate. While uptake of exogenous pyruvate in MDA-MB-231 breast cancer cells is increased by cocultured CAFs, subsequent 13C MRS indicates 13C-labeled lactate in the media conditioned by 13C-pyruvate-treated MDA-MB-231 cells, closing the cycle.