Artificial Sweetener Saccharin Shows Promise In Cancer Treatment

In In The News by Barbara Jacoby



You may have heard whispers that the artificial sweetener saccharin (commonly known as Sweet‘N Low) is a carcinogen. But according to a new study presented today at the 249th National Meeting & Exposition of the American Chemical Society, it could actually be useful in developing treatments for aggressive cancers by deactivating a protein found to facilitate the spread of cancer.

Back in the 1970s, scientists found a link between saccharin and bladder cancer in lab rats. By law, this finding required a warning on packaging for saccharin products, and so the sweetener was then slapped with a label indicating risks for consumption — and a stigma.

After subsequent testing, researchers found out that rats have high pH levels, high calcium phosphate, and high protein levels in their urine — something that humans don’t have. These conditions led proteins in the urine to bind to the saccharin, producing tiny microcrystals that harm the bladder lining.

In the late 1990s, the National Toxicology Program and the International Agency for Research on Cancer looked at all the available research on saccharin and determined it is not a human carcinogen. In 2010, the Environmental Protection Agency removed saccharin from its list of hazardous substances.

However, for some, the stigma has remained. Now, though, researcher Robert McKenna, PhD, a professor in the Department of Biochemistry and Molecular Biology at the University of Florida, may have uncovered a way for saccharin to help treat some of the most aggressive types of cancer.

Through x-ray crystallography, McKenna’s new research delves deeper into the methods by which saccharin binds to and shuts down a protein called carbonic anhydrase IX.

There are 14 other carbonic anhydrase proteins that the body needs to transport carbon dioxide out of tissues and maintain the blood’s pH —or, in other words, to keep the body’s acid-alkaline balance in the ideal range — but carbonic anhydrase IX is not one of them. Instead, this particular protein drives the growth of aggressive cancers, including those of the breast, lung, liver, kidney, pancreas, and brain.

Researchers found that saccharin-based drugs may stunt the growth of these cancers, preventing spread by binding to the carbonic anhydrase IX that’s encouraging those ideal conditions for cancers to take hold and spread in the body.

Since carbonic anhydrase IX is not found in healthy human cells anywhere in the body, with the exception of the GI tract, drugs with saccharin shouldn’t interfere with the growth of healthy tissues or cause unintended side effects; the sweetener would simply bind to the harmful protein, researchers say.

This is a big change for a substance that was once considered dangerous, even just a few years ago — and McKenna thinks this abundant substance could generate major impact in the realm of cancer treatment in the years to come.

“It never ceases to amaze me how a simple molecule, such as saccharin —something many people put in their coffee every day —may have untapped uses, including as a possible lead compound to target aggressive cancers,” McKenna said in a statement. “This result opens up the potential to develop a novel anti-cancer drug that is derived from a common condiment that could have a lasting impact on treating several cancers.”

McKenna and his team are currently experimenting with saccharin-based compounds on breast and liver cancer cells. If these prove successful, they will likely move to animal trials.