A team of researchers from Cambridge (UK) has presented a new study showing that some foods can influence the spread of certain types of cancer. Asparagus, for example, is one of them. Specifically asparagine, a nutrient present in this vegetable (asparagus). If this nutrient is absent, the growth of breast cancer may be reduced, the authors point out in a study whose results are reported in the journal Nature.
The team observed that the amino acid asparagine is vital for the growth of breast cancer. Previous studies have already shown that poultry and other seafood are also associated with the growth of breast cancer because they have high levels of asparagine. For this study, the team conducted their animal study at Cancer Research UK Cambridge Institute to understand the unique features of tumor cells that circulate in the blood and where cancer spreads.
The experts treated mice with an aggressive form of triple negative breast cancer that grow and spread faster than most other types of cancer cells. It is called triple negative because it lacks receptors for the hormones estrogen and progesterone and produces little protein called HER2. As a result, it resists common treatments, which target these factors, and has a higher than average death rate.
They found that the appearance of asparagine synthetase (the enzyme cells used to produce asparagine) in a primary tumor was associated with a later large spread of the cancer.
The researchers also found that metastasis was severely limited by reducing asparagine synthetase, thanks to drug treatment or dietary restriction. When the laboratory mice were given food rich in asparagine, the cancer cells spread more quickly. Testing drugs to block asparagine, they found that their tumors had a significantly slower spread rate throughout the body, and this, in turn, prolonged the lives of the mice thanks to drugs that blocked asparagine.
“The results of the study suggest that changes in diet can affect both how an individual responds to primary therapy and how likely the disease will spread later, ” said Gregory J. Hannon, study leader.
Experts are considering conducting a human clinical trial in which healthy participants would eat a diet low in asparagine. If the diet results in a decrease in asparagine levels, the next scientific step would involve a clinical trial with cancer patients. That test is likely to use dietary restrictions, as well as chemotherapy and immunotherapy.
Studying the effects of asparagine could also alter treatments for other types of cancer, the authors comment.
“This study may have implications not only for breast cancer, but for many metastatic cancers,” explains Ravi Thadhani, a co-author of the work.
NOTE : Foods rich in asparagine include dairy, buttermilk, beef, chicken, eggs, fish, shellfish, asparagus, potatoes, legumes, nuts, seeds, soybeans, and whole grains. Foods low in asparagine include most fruits and vegetables.
Referencia: Simon R. V. Knott, Elvin Wagenblast, Showkhin Khan, Sun Y. Kim, Mar Soto, Michel Wagner, Marc-Olivier Turgeon, Lisa Fish, Nicolas Erard, Annika L. Gable, Ashley R. Maceli, Steffen Dickopf, Evangelia K. Papachristou, Clive S. D’Santos, Lisa A. Carey, John E. Wilkinson, J. Chuck Harrell, Charles M. Perou, Hani Goodarzi, George Poulogiannis, Gregory J. Hannon. Asparagine bioavailability governs metastasis in a model of breast cancer. Nature, 2018; DOI: 10.1038/nature25465
