These analyses show that mRNA expression levels of enzymes belonging to the serine synthesis pathway are generally elevated in T-ALL, with the most significant increase for PSPH. In line with this finding, PSPH protein levels were elevated in primary T-ALL patient sample xenografts as compared to normal bone marrow and acute myeloid leukemia samples (Supplementary Fig. 11B). Here, PSPH is linked to acute lymphoblastic leukemia.