Disclosed herein are methods of reducing cytotoxicity of a chemotherapeutic agent to non-cancer cells by administering to a subject with cancer an effective amount of an agent that inhibits CD47 signaling and a chemotherapeutic agent. Example disclosed methods reduce cardiotoxicity of a chemotherapeutic agent. Also disclosed are methods of increasing cytotoxicity of a chemotherapeutic agent in cancer cells by administering to a subject with a tumor an effective amount of an agent that inhibits CD47 signaling and a chemotherapeutic agent. In some embodiments, the inhibitor of CD47 signaling is administered to the subject before, during, or after the administration of the chemotherapeutic agent.
