Breast Cancer Metastasis Linked to Compound Found in Asparagus and Other Common Foods
There are dozens of factors that influence the spread of cancer in the body, but a recent study has found a new factor, and this time it’s one you may have a little bit of control over.
In the study, published in the journal Nature, researchers used a drug called L-asparaginase to block the compound asparagine in mice with aggressive forms of breast cancer. In these animals, secondary tumors generally show up within a few weeks, and the disease becomes fatal in just months. By blocking asparagine, however, researchers were able to reduce the spread of cancer. Reducing the amount of asparagine in the mice’s diet appeared to help as well, although to a lesser extent.
Asparagine is an amino acid that acts as a building block for proteins. The body makes some of it naturally, but it is also found in several different types of food. It was first identified in asparagus but is now known to exist in beef, poultry, eggs, fish, seafood, certain dairy products, potatoes, nuts, legumes, soy, and more. The compound appears to help cancer cells change into a form that is more easily carried through the bloodstream to other organs.
The spread of cancer to the bones, lungs, brain, and other vital organs is the main cause of death in breast cancer patients. Cancer that is confined to the breast is not fatal. Therefore, stopping the metastasis, or spread, of malignant cells altogether would effectively end breast cancer deaths.
Lead scientist Professor Greg Hannon, director of the Cancer Research UK Cancer Institute in Cambridge, had this to say about the discovery:
“This is a very promising lead and one of the very few instances where there is a scientific rationale for a dietary modification influencing cancer.”
However, because asparagine is present in so many different types of foods, many of which are healthy and nutrient-laden, it’s unlikely that experts will ever recommend that breast cancer patients cut it out of their diets completely, especially without speaking with their doctors first.
But there’s something to be said at least for the possibility that cutting back on foods that contain asparagine could help in slowing the spread of cancer, along with traditional treatment plans. You should not, however, attempt a low-asparagine diet without first discussing it with a doctor.
“This is one case where we can show at a deep biochemical level how a change in diet can impact properties of cells that are relevant to the progression of lethal disease,” Hannon says. “But of course, until human studies are done, this isn’t a DIY method to prevent cancer.”
Even if diet isn’t an effective route to cut down on asparagine and slow the spread of cancer, the discovery of this compound’s role in metastasis could aid researchers as they continue to work on developing effective and safe drugs for preventing the spread of cancer.
L-asparaginase, a drug currently being studied for this purpose, breaks the amino acid down in the bloodstream, preventing it from being used by cancer cells but also depriving the body of an element it needs for the production of proteins. However, future targeted drugs could block the production of asparagine altogether.