Salicylic acid is an ancient drug that has been used as the main ingredient in nonsteroidal anti-inflammatory drugs aspirin and diflunisal to stop inflammation. Now, scientists from the Gladstone Institutes in San Francisco have found that salicylic acid can also prevent cancer.

The study, published on May 31 in eLife, states that both salicylic acid and diflunisal stops the action of the proteins p300 and CREB-binding protein (CBP) which are associated with cell growth, preventing cellular damage. These sister proteins also control the proteins that cause inflammation and help control the gene expression throughout the body.

“Salicylic acid is one of the oldest drugs on the planet, dating back to the Egyptians and the Greeks, but we’re still discovering new things about it,” adds the study’s senior author Eric Verdin, Gladstone Institute of Virology and Immunology’s associate director. “Uncovering this pathway of inflammation that salicylic acid acts upon opens up a host of new clinical possibilities for these drugs.”

salicylic acid

Salicylic acid, the key compound in aspirin, can prevent cancer. Credit: Wikimedia/Ragesoss

Previously, researchers linked p300 with AML1-ETO, a protein that encourages the development of leukemia. In the team’s recent study, they found that blocking p300 with diflunisal prevented the leukaemia progression as well as reduced the tumor size in the mice tested. These findings imply that targeting both p300 and CBP can help prevent cancer.

“The ability to repurpose drugs that are already FDA-approved to be part of novel therapies for cancer patients is incredibly exciting,” says the study’s co-author Stephen Nimer, the director of Sylvester Comprehensive Cancer Center at the University of Miami Miller School of Medicine. “We have conducted a clinical trial of salicylic acid in patients with hematologic cancers and found it to be safe. Thus, this collaborative effort to develop novel epigenetic therapies is an important next step in our journey to find more effective treatment for leukemia patients.”

The research team is currently planning a clinical trial to test the efficacy of salicylic acid in preventing leukemia progression in human subjects. Moreover, apart from stopping cancer, the team believes that further understanding of salicylic acid can lead to preventing other diseases such as inflammatory diseases, type 2 diabetes, and Alzheimer’s or other neurodegenerative disorders.