Abstract: This invention relates, e.g., to a composition that, at room temperature, when contacted with a sample comprising phosphoproteins, can fix and stabilize cellular phosphoproteins, preserve cellular morphology, and allow the sample to be frozen to generate a cryostat frozen section suitable for molecular analysis. The composition comprises (1) a fixative that is effective to fix the phosphoproteins, and that has a sufficient water content to be soluble for a stabilizer and/or a permeability enhancing agent); (2) a stabilizer, comprising (a) a kinase inhibitor and (b) a phosphatase inhibitor and, optionally, (c) a protease (e.g., proteinase) inhibitor; and (3) a permeability enhancing agent (e.g. PEG). Methods are described for preserving phosphoproteins, using such a composition. Also described are endogenous surrogate markers for monitoring protein degradation, including the loss of posttranslational modifications (such as phosphorylation), e.g.

Abstract: The present invention describes devices and methods for performing protein analysis on laser capture microdissected cells, which permits proteomic analysis on cells of different populations. Particular disclosed examples are analysis of normal versus malignant cells, or a comparison of differential protein expression in cells that are progressing from normal to malignant. The protein content of the microdissected cells may be analyzed using techniques such as immunoassays, 1D and 2D gel electrophoresis characterization, Western blotting, liquid chromatography quadrapole ion trap electrospray (LCQ-MS), Matrix Assisted Laser Desorption Ionization/Time of Flight (MALDI/TOF), and Surface Enhanced Laser Desorption Ionization Spectroscopy (SELDI).