To quantify the amounts of ceramide in breast cancer cells with high and low expression of UGT8, we modified and applied a previously described HILIC-MS/MS methodology [26] involving monitoring of the characteristic ion at 264 m/z, a product of fragmentation of both Cer and HexCer (hexosyl-ceramide) but not oligosaccharide substituted ceramides. The gene discussed is UGT8; the disease is breast carcinoma.