Research Of Proteins Related Colon Carcinoma Hepatic Metastasis In Serum By Comparative Proteomics

Cell metastasis is the most important character of malignant tumor. The carcinomatous metastasis of colon cancer usually happen on liver. Despite substantial progresses made in colon carcinoma hepatic metastasis clinical and basic research, the overall prognosis of colon carcinoma remains dismal because of the late diagnosis and low resection rate. Although CEA can be an biomarker, the specificity and sensitivity of which are still not satisfied. Therefore, screening novel colon carcinoma hepatic metastasis biomarkers are still needed.Proteomics is becoming the hot field of biological study in the functional genomic era. The scope of proteomics is to study the expression profile, function and cross reactivity of all cell, tissue or organism proteins under specific circumstances. Because of the high throughput and resolving power, proteomics techniques are becoming strong tools for contemporary medical research.The challenge of clinical proteomic studies is to link protein expression profiles to specific disease phenotypes and to find out relevant biomarkers in order to develop diagnostic tools. Two-dimensional electrophoresis (2-DE) is a highly resolving technique for arraying proteins by isoelectric point and molecular mass. To contribute to the development and improvement of molecular markers for diagnostics and prognostics and of therapeutic targets for the disease, we have largely expanded the currently available colon carcinoma hepatic metastasis serum. Protein identification was done by peptide mass fingerprinting with matrix assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI -TOF-MS).PART ISAMPLE HANDING OF SERUM OF COLON CARCINOMA HEPATIC METASTASISObjective:To establish and evaluate the method of removing albumin and IgG in serum proteomics by Two-dimensional electrophoresis(2-DE).Methods: The blood samples were collected in accordance with Human Proteome Organization Plasma Proteome Project. After depleting of the six plasma proteins of highest abundance by the MARS, the remaining low- and medium-abundance serum proteins were isolated and concentrated.Results: The method of removing serum albumin and IgG and 2-DE was established stably, increasing sharpness of separation of low-abundance proteins and decreasing the disturbing of high abundance proteins in 2-DE.Conclusion: The Multiple Affinity Removal System can depleting of the six serum proteins of highest abundance.PART IIESTABLISHMENT OF SCREENING SERUM BIOMARKERS BY TWO-DIMENSIONAL POLYACRYLAMIDE GEL ELECTROPHORESISObjective:To establish a two-dimensional polyacrylamide gel electro- phoresis(2-DE)technique for serum proteomics.Methods: Various conditions of serum proteomic 2-DE were adjusted and optimized.Results: A steady 2-DE technique was established.Conclusion: The established method of purifying serum proteins may be foundation in searching serology marker of diseases. PART IIIIDENTIFICATION OF SERUM PROTEINS RELATED TO COLON CARCINOMA HEPATIC METASTASISObjective:To analyze the 2-DE protein separation and identification by PMF in colon carcinoma and colon carcinoma hepatic metastasis.Methods: We used 2-DE and MALDI-TOF based proteomics to compare the protein profiles between colon carcinoma and colon carcinoma hepatic metastasis.Results: 14 protein spots were discovered differently and 10 were identified by PMF,including 6 proteins as TGF-β1,Geranylgeranyl transferase type-1 were up-regulated and 4 proteins as Protein kinase C were down-regulated in colon carcinoma hepatic metastasis.Conclusion: 2-D gel images of colon carcinoma and colon carcinoma hepatic metastasis showed different protein expression. The variety of proteins may be concerned with metastatic mechanism of colon carcinoma hepatic metastasis possibly.