Laser capture microdissection and colorectal cancer proteomics.

The ability to define protein profiles of normal and diseased cells is important in understanding cell function. Laser capture microdissection permits the isolation of specific cell types for subsequent molecular analysis. In this study we have established conditions for obtaining proteomic information from laser capture microdissected colorectal cancer cells. Laser capture microdissection was performed on toluidine blue-stained frozen sections of colorectal cancer. Proteins were solubilized from microdissected cells and the solubilized proteins were separated by two-dimensional gel electrophoresis: protein spots were characterized by peptide mass mapping using matrix assisted laser desorption ionization-time of flight mass spectrometry. Proteins isolated from laser capture microdissected tissue retained their expected electrophoretic mobility and peptide mass mapping was also unaffected. The ability to study the protein expression profile of specific cell types will allow for the identification of novel disease markers and therapeutic targets and also provide for the enhanced understanding of pathogenetic mechanisms.