What’s that smell?

Top Line: Bioavailability of asparagine may enhance the metastatic potential of breast tumors.
The Study: Certain sub-clones of breast tumor cells are really good at producing circulating tumor cells. But not all circulating tumor cells take up shop as metastatic disease. This month’s Nature study evaluated whether any candidate genes are associated with increased metastatic potential. Interestingly, high expression of asparagine synthetase (which helps make asparagine) was strongly associated with metastatic lesions. How? Higher amounts of asparagine increased expression of proteins involved in epithelial to mesenchymal transition (EMT). And there’s more. Metastases blossomed in animals fed high asparagine diets, while mets withered away in other animals on low asparagine diets. Interestingly, diet didn’t affect primary tumor growth much since normal breast asparagine levels are normally very high. Who knew.
Bottom Line: Modulating serum asparagine via something like asparaginase or even diet could limit the metastatic potential of breast tumors. Add that to the list of reasons for you (and your roommate) to go lite on the asparagus.