Gallium corroles can image tumors and destroy them

Scientists know that gallium corroles—molecules that are one carbon shy of being porphyrins—can kill cancer cells. Gallium corroles also happen to have properties that make them excellent fluorescence imaging agents. That means doctors could potentially follow a gallium corrole’s progress as it slays cancer cells. A team led by Harry B. Gray of Caltech and John Termini and Punnajit Lim of the Beckman Research Institute of the City of Hope now show that adding a carboxylate group to a gallium corrole improves the compound’s ability to get into cells (Proc. Natl. Acad. Sci. USA 2016, DOI: 10.1073/pnas.1517402113). With this modification, the gallium corroles were able to kill several types of cancer cells at doses lower than what’s needed for the popular chemotherapeutic agent cisplatin to be effective. The team made two carboxylated gallium corroles. One of them they modified with aminocaproic acid (shown). The other they derivatized with phosgene. Because synthesis of the former requires no harsh reagents, the researchers suggest it could be a promising lead for anticancer and imaging use.