An amino acid found in a variety of foods including asparagus has been linked to the spread of breast cancer.
A team of international cancer researchers have shown in mice that limiting the consumption of the amino acid called asparagine stopped the spread of triple-negative breast cancer.
Published in medical journal Nature, experts say the study adds to a growing body of evidence that suggests diet can influence the course of the disease.
"The study results are extremely suggestive that changes in diet might impact both how an individual responds to primary therapy and their chances of lethal disease spreading later in life," said senior author, Gregory Hannon at England's University of Cambridge.
Amino acids are used by cells to make proteins. Foods rich in asparagine include dairy, whey, beef, poultry, eggs, fish, seafood, asparagus, potatoes, legumes, nuts, seeds, soy and whole grains.
Most fruits and vegetable are low in asparagine.
A team of international cancer researchers from the UK, US and Canada studied the impact of asparagine in triple-negative breast cancer cells, which grow and spread faster than most other types of cancer cells.
It was discovered that the appearance of asparagine synthetase - the enzyme cells used to make asparagine - at the primary tumour site was strongly associated with later cancer spread.
The researchers also found that metastasis was greatly limited by reducing asparagine synthetase. When the laboratory mice were given food rich in asparagine, the cancer cells spread more rapidly.
Investigators now are considering conducting an early-phase clinical trial in which healthy participants would consume a low-asparagine diet.
Studying the effects of asparagine could also alter treatments for other types of cancer, Ravi Thadhani at Cedars-Sinai Hospital said.
"This study may have implications not only for breast cancer, but for many metastatic cancers," he said.
