Difference in the level of expression of genes for sphingolipid biosynthesis through ST of human ovarian normal surface epithelial cells and epithelial tumor cells. The relative mRNA levels were analyzed for normal human ovarian surface epithelial cells (n = 12) and epithelial ovarian tumor cells (n = 12) using Affymetrix HG U133 Plus 2 Gene Chips. The fold differences of mRNA level for the shown steps of the de novo sphingolipid biosynthesis pathway were imported into a KEGG style pathway heatmap. (A) Fold difference in gene expression for ovarian epithelial carcinoma/normal epithelial cells are represented by the color scale (red = higher; blue = lower). (B) Relative mRNA levels for Gal3ST1 and GalCer synthase in each of the normal ovarian surface epithelial cells (n = 12) and ovarian epithelial carcinoma (n = 12).