In cancer cells, the expression of ACL is strongly upregulated56 and reductive glutamine metabolism, catalyzed by IDH1 and IDH2, results in an enhanced lipid biosynthesis.41 Related to this, overexpression of fatty acid synthase confers growth and survival advantages on cancer cells,57 while, on the contrary, inhibition of ACL suppresses tumor cells growth.58 Taken together, these findings indicate that a sustained production of lipids from AcCoA derived from glutamine takes place in cancer cells and is necessary to support their growth and survival. The gene discussed is ACLY; the disease is cancer.