Personalized methods of treating cancer

A method for treating a cancer having dysregulated polyamine metabolism in a subject in need thereof, wherein the cancer having dysregulated polyamine metabolism is breast cancer, colorectal cancer, pancreatic cancer, or brain cancer, the method comprising administering to the subject a therapeutically effective amount of a dietary product, wherein:

• the dietary product comprises at most about 0.5% (w/w) of cysteine or cystine;
• the dietary product comprises at least about 7.5% (w/w) of methionine;
• the therapeutically effective amount of the dietary product is from about 0.5 g/kg/day to about 1 g/kg/day;
• and
• the subject is undergoing a cancer therapy for the cancer having dysregulated polyamine metabolism.