Valproic acid (VPA) is currently prescribed as an anti-seizure medication and mood stabilizer, but it is also being studied as an anticancer agent because it inhibits histone acetyl transferases, which help control gene expression by changing DNA structure.
Johann Christoph Brandes MD, PhD, of the Atlanta Veterans Affairs Medical Center and Emory University in Atlanta, led a team that assessed the anticancer effects of VPA in a study of 439,628 veterans, of whom 26,911 were taking the medication for bipolar disorder, post-traumatic stress disorder, migraines, and seizures.
Veterans who took VPA for at least one year had a 34 percent lower risk of developing head and neck cancer compared with those who did not take the medication. Higher doses and longer duration of VPA use seemed to provide additional benefits. No significant differences were observed for lung, bladder, colon, and prostate cancer incidences.
"A 34 percent risk reduction for the development of head and neck cancer with VPA use could result in the prevention of up to approximately 16,000 new cases and 3,000 to 4,000 annual deaths in the US alone," said Dr. Brandes. "Head and neck cancer is an important global health crisis, and low cost and low toxicity prevention strategies like VPA use have a high potential impact on pain, suffering, costs, and mortality associated with this disease."