A comparison of the relative levels of mRNA expression for enzymes of sphingolipid metabolism was published in the supplement of reference [128] and a doctoral thesis [111] for the 59 cancer cell lines in the NCI 60-cell line drug screen [129] (NCI-60, http://discover.nci.nih.gov/cellminer/, accessed on 12 December 2024), and there were about a dozen lines from multiple categories (i.e., breast, colon, glioma, leukemia, ovarian, and renal cancer) that appear to have higher expression of SPTLC 1 or 2 but average or lower expression of KDSR. This evidence concerns the gene KDSR and leukemia.