Title: Clinical Proteomics in Cancer Research – Promises and Limitations of Current Two-Dimensional Gel Electrophoresis
Volume: 15
Issue: 23
Author(s): Yasuo Iwadate
Affiliation:
Keywords:
Protein, proteome, marker, two-dimensional electrophoresis (2-DE), matrix-assisted laser disorption/ionization time of flight mass spectrometry (MALDI-TOF MS)
Abstract: Cancer can be defined as a deviated protein network system toward dysregulated cellular proliferation. Alteration in the content and functional state of the proteins with many linkages may shift the equilibrium state of the protein signaling network to enhance a survival advantage of the affected cells. Searching for such hub proteins is the main purpose of the cancer proteomics. Although the progression in the vanguard proteomic technologies would largely contribute to cancer diagnosis and treatment in the future, the technology most frequently used for the analysis of clinical tissue samples is the two-dimensional gel electrophoresis (2DE) combined with matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS). Accumulation of 2DE data has generated many candidate biomarkers with potential clinical value. The identified proteins are restricted to a subset of the predicted human proteome, and ubiquitously exist in all normal cells taking important roles in the basic biological functions. Although these proteins can be used as valuable prognostic markers, the low-abundance proteins which is tissue-specific and useful as diagnostic markers could not easily be found by the standard 2DE technology alone. None of the current proteomic technologies can identify the whole proteome by themselves. Adequate combinations of different approaches not only in proteomics but in immunological methods would be necessary for the tissue specific markers.