Called photodynamic therapy, most of the current methods of using it involve creating a particular deadly form of oxygen or heating up particles or chemicals in tumors. Now, a researcher has found a way to use the therapy to alter the pH of tumors so that they commit suicide without harming the rest of the body.

When a tumor grows in the body, it creates an acidic environment on the outside of its cells. This causes blood vessels to attach to it to try to remove the acid. In something of a biological trick, the tumor then commandeers the blood vessels and uses them as a source of nutrients to help it grow.

Working out of the University of Texas at San Antonio (UTSA), biology professor Matthew Gdovin decided to try an acid trick of his own. He injected a chemical compound called nitrobenzaldehyde into tumors. He then hit the tumors with a beam of ultraviolet light that caused the chemical to make the tumors so acidic that they, in effect, committed suicide.