| Abstract: | AIM: To discover novel biomarkers for early diagnosis, prognosis or treatment of human colorectal cancer. METHODS: i TRAQ 2D LC-MS/MS analysis was used to identify differentially expressed proteins(DEPs) in the human colonic epithelial carcinogenic process using laser capture microdissection-purified colonic epithelial cells from normal colon, adenoma, carcinoma in situ and invasive carcinoma tissues. RESULTS: A total of 326 DEPs were identified, and four DEPs(DMBT1, S100A9, Galectin-10, and S100A8) with progressive alteration in the carcinogenic process were further validated by immunohistochemistry. The DEPs were involved in multiple biological processes including cell cycle, cell adhesion, translation, m RNA processing, and protein synthesis. Some of the DEPs involved in cellular process such as "translation" and "m RNA splicing" were progressively up-regulated, while some DEPs involved in other processes such as "metabolism" and "cell response to stress" was progressively downregulated. Other proteins with up- or down-regulation at certain stages of carcinogenesis may play various roles at different stages of the colorectal carcinogenic process. CONCLUSION: These findings give insights into our understanding of the mechanisms of colorectal carcinogenesis and provide clues for further investigation of carcinogenesis and identification of biomarkers. |
