AT Synthase (IMAGE) American Chemical Society Caption In a finding that could lead to more effective anti-cancer medication, scientists exposed breast cancer cells to a substance that blocks a protein called ATP synthase. The cancer cells were killed while normal ones were preserved. Credit Courtesy of Hsin-Yi Chang and Hsueh-Fen Juan Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.