Abstract:Objective：To screen the associated proteins of clinical stage of colorectal carcinoma(CRC) in order to provide the basis of molecular biological stages and outcome prediction of CRC.
Methods ：Total protein from colorectal carcinoma tissues were extracted, differential proteome profiles were established and analysized by means of immobilized pH gradient-based two-dimesional polyacrylamide gel electrophoresis(2D-PAGE) and matrix-assisted laser desorption/ionization time of flight mass spectrometry(MALDI-TOF-MS). Immunohistochemical method was used to assess the results mentioned above.
Results：Well-resolved, reproducible 2-DE profiles of human colorectal carcinoma tissues were obtained. Avarage protein dots were 970±41，980±32，1010±43，1240±34 in stageⅠ, stageⅡ, stageⅢ, stageⅣ, respectively; compared to stageⅠ, differential expressed protein dots was 52.00±12 in stageⅡ; 42.00±11 in stageⅢ; 72.00±15 in stageⅣ ;30 differentail expressing proteins were analysized by mass spectrometry and bioinformation, part of them were well characterized . Three proteins (Annexin Ⅱ,Annexin Ⅳ and HSP27) were overexpressed in stageⅡ, stageⅢ, stageⅣ, and Liver fatty acid-binding protein(LFABP) was only overexpressed in stageⅣ. Resullts of immunohistochemical assay for AnnexinⅡ and LFABP were consistant with proteomic results.
Conclusions：Differentail expressed proteins exist in different clinical stage of CRC, which would be as biomarkers for diagnosis and prediction of prognosis of CRC.