Because most malignant cells rely on the activity of the protein telomerase for their immortality, it has been proposed that a drug that inactivates telomerase might be effective against a broad spectrum of malignancies. At the same time, most healthy tissues in the body express little if any telomerase, and would function normally in its absence. Currently, inositol hexaphosphate, which is available over-the-counter, is undergoing testing in cancer research due to its telomerase-inhibiting abilities.[32]