Glutathione is an antioxidant that cancer cells seem to be “addicted” to as an energy source, according to a study that opens new avenues of research and the possibility of developing a drug capable of limiting the way tumors use this nutrient.

“Cancer cells and normal cells potentially use different food sources, and we discovered how cancer cells, specifically, break down this antioxidant and use it as fuel,” he explains. researcher Isaac Harris, one of those responsible for the work carried out in mice and human tissue.

Although glutathione was discovered 100 years ago, “we continue to discover completely new aspects of its biology,” adds the scientist, who, however, says that “there is still a lot to understand, but we are hopeful that we can apply these discoveries to new therapies.”

Details of this study that identifies an unexpected food source for tumors (especially cysteine, one of the components of glutathione) are published in the journal Nature.

Glutathione in breast tumors: study findings

Glutathione is produced naturally by the body, but it is also widely marketed as an antioxidant supplement. Although this is usually accompanied by claims about its health benefits, this contrasts with the more nuanced and cautious messages from institutions, recalls a statement. from the University of Rochester Medical Center, in the United States.

“It is important to understand how cancer appropriates certain substances that we could consider harmless,” emphasizes Harris, from the Wilmot Cancer Institute of the aforementioned university, who emphasizes that antioxidants can be a double-edged sword in some circumstances.

For the new research, the team analyzed breast tumor samples from people who had donated their tissue to the Wilmot Biobank. By isolating and examining the fluid inside these tumors, the researchers found abundant stores of glutathione, confirming that the tumors “eat up” it as a source of nutrients.

A drug to block the use of the antioxidant

Using preclinical models of breast cancer, the team discovered that it could slow tumor growth by blocking the cancer’s ability to use glutathione.

Scientists used advanced technology to search for therapies that could inhibit a tumor’s ability to use this antioxidant and identified “one promising candidate,” a drug developed nearly a decade ago.

They are now exploring new ways to improve it and to precisely identify the proteins involved in delivering glutathione to tumors. The goal is to develop novel therapies that destroy tumors without affecting healthy cells, the authors say.

The discovery could be applied more broadly to other types of cancer, as preliminary research shows that many tumors consume glutathione.

Should glutathione supplements be avoided?

Harris emphasized that although the antioxidant glutathione is linked to cancer, this does not mean that people should stop consuming whole foods rich in antioxidants.

“It’s important to eat a balanced diet with fruits and vegetables. It can control weight, reduce inflammation, and support a healthy immune system,” Harris says, but people should be cautious about taking supplements in general, especially glutathione.

In this sense, it indicates that taking a pill that is not regulated by the FDA (United States Food and Drug Administration) and that has a high concentration of glutathione “may present risks.”

FEW (EFE, NatureUniversity of Rochester)