It has been demonstrated that breast cancer cell lines expressing high levels of c-MYC were dependent on Gln for their survival and growth.53 As shown in Table 1, significant decrease of Gln was observed in patients with pancreatic cancer,27, 38 Lung cancer, gastric cancer, colorectal cancer, breast cancer and prostate cancer.29 On the other hand, the increased Glu levels in colorectal cancer patients30 and breast cancer patients30, 31, 32 could also be interpreted as the result of increased Gln metabolism in tumor cells. This evidence concerns the gene MYC and breast cancer.