It is also noteworthy that in our leukemia cell models, inhibition of the Gln metabolism and the associated upregulation of the serine pathway did not stimulate glucose metabolism contrary to experimental solid tumor models where serine, by binding and activating the pyruvate kinase isoform PKM2, was reported to promote the glycolytic flux [20, 21, 26, 27]. Here, PKM is linked to leukemia.