Investigation of the potential of capillary electrophoresis with off-line matrix-assisted laser desorption/ionization time-of-flight mass spectrometry for clinical analysis: Examination of a glycoprotein factor associated with cancer cachexia

The potential of capillary electrophoresis (CE) with offline matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry has been demonstrated for the examination of a glycoprotein factor associated with cancer cachexia, A comparison of CE profiles of a healthy volunteer and a cancer patient shows the presence of additional peaks in the electropherogram of the cancer patient that could be associated with cachexia. Micropreparative CE was performed with 180-mu m fused silica capillary columns with tapered ends to collect CE fractions for further identification by MALDI-TOF-MS. The analysis of crude urine samples of cancer patients exhibiting cachexia, as well as CE fractions, with MALDI-TOF-MS using ferulic acid as the matrix shows a number of characteristic ions at m/z values of similar to 24 and similar to 67 kDa. The 24-kDa peak may be identified as the cachectic factor, a glycoprotein, whereas the peak at 67 kDa is identified as albumin, which is present in urine of most patients, and to which the cachectic factor is non-covalently bound. The combined use of CE and MALDI-TOF-MS was successful in detecting cachexia in all of the patients in this study, including one patient that was in an early phase of the disease.