SPAG6 and neoplasm: All these tumor cell lines were found to be SPAG6 and L1TD1 methylated with percentages of methylation ranging between 71% (SK-OV3 cells) and 98% (FaDu cells) for SPAG6 methylation and between 88% (BxPC-3 cells) and 100% (FaDu cells) for L1TD1 methylation (Additional file 1: Table S4).