DDO and neoplasm: We identified 14 genes (SLC7A7, IL41, SLC43A2, SLC38A5, ACY3, SLC6A12, SLC38A1, DDO, GLUL, ASS1, ABAT, GFPT2, SLC6A6, SLC36A1, SLC38A4) that correlate positively and 13 genes (SLC7A5, SLC16A10, SLC3A1, GLUD2, GAD2, SLC3A2, SLC43A1, PPAT, ADSL, CAD, SLC6A15, SLC7A1) that correlate negatively with leukocyte fraction in tumor tissue (Fig. 6D), with similar patterns observed with gene expression correlations with cytolytic activity (Fig. 6E).