In the past decade, high-throughput glycan arrays as well as glycopeptide arrays have been increasingly used. These approaches already contribute to biomarker

research in breast and ovarian cancer, and will be powerful tools in the future, when increasing efficiency, sensitivity and preciseness will allow cancer diagnostics and therapeutics of high-sensitivity. Despite detected TACA-specific interactions with antibodies, it is crucial to conclude that TACA are specifically expressed or shed by cancer cells and the direct proof of their presence is often missing. It is therefore Inhibitors,research,lifescience,medical required to test matched serum samples from the same patients using alternative methods. Matched tissue samples of normal and cancer patients can allow the identification of TACA directly. This can easily be Inhibitors,research,lifescience,medical achieved by Caspase activity assay standard immunohistochemistry using mAbs or lectins. The latter are known to bind various glycan structures sharing carbohydrate motifs or epitopes (for review see [174]). Other possibilities are the identification Inhibitors,research,lifescience,medical of glycan structures by MS-based profiling and the analysis of glycan complements in plasma and tissues, which allows for the comprehensive

analysis of membrane protein glycosylation. The high-throughput glycan profiling by MS requires only minute volumes of patient serum, thus representing an essentially non-invasive diagnostic method. This highly sensitive method in contrast to glycan-based immunoassays, detecting anti-TACA antibodies (glycan and glycoconjugate Inhibitors,research,lifescience,medical based platforms), can be used for direct glycomic mapping and as a proof

of glycoarray-based findings. In breast cancer research a sensitive specific MS (MALDI-TOF MS)-based glycomic Inhibitors,research,lifescience,medical profile was performed to analyze N-glycans in serum of control as well as early- and late-stage breast cancer patients. Various MS-based technologies in combination with other methods (high performance 17-DMAG (Alvespimycin) HCl liquid chromatography, capillary electrophoresis) were also consistently used for the investigation of gynecological cancer associated glycan alterations over the past decade [93,135,144]. Differences in glycomic profiles revealed a substantial increase of fucosylation (both in core structures and the branched segments) in cancer patients, whereas various sialylated structures in serum presented a less clear picture. In one study changes in relative intensities of eight glycans are characteristic of breast cancer, whereas some other glycan structures might contribute additionally to distinctions in the recognizable patterns [175].