title: New prognosis biomarkers identified by dynamic proteomic analysis of colorectal cancer.
abstract: The initiation, promotion and progression of human cancer are complex, polygenic, multi-factored processes. Through systematic proteomic analysis, different stages of CRC (colorectal cancer) biopsies were examined, and 199 differentially expressed proteins were detected between TNM (the tumor, nodes, and metastasis) stages I-IV and normal tissue (One-Way Analysis of Variance, ANOVA; p≤ 0.05). Instead of looking for biomarkers to distinguish CRC from normal or identify metastatic tumors, we focused on the variation tendency of CRC carcinogenesis and the dynamic expression patterns of proteins among the different stages. Som (self-organizing map clustering) analysis revealed eight unique expression patterns and that the cancer-related proteins were dynamically expressed, and their expression levels changed continuously throughout tumorigenesis. Molecular evidence emerged much earlier than visible, clinical or histological changes, which shows the potential prospect of building molecular staging. Proteins identified by MALDI-TOF MS (Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry) were mainly involved in energy metabolism, acetylation and signaling pathways. Validation experiments using immunoblotting and immunohistochemistry (IHC) agreed with the 2D-DIGE (two-dimensional difference in gel electrophoresis) data. After survival classifier and LOOCV (leave-one-out cross-validation) analyses, the new prognostic biomarkers (78 kDa Glucose-Regulated Protein precursor (GRP78), Fructose-bisphosphate Aldolase A (ALDOA), Carbonic Anhydrase I (CA1) and Peptidyl-prolyl cis-trans isomerase A or Cyclophilin A (PPIA)) provided good survival prediction for TNM stage I-IV patients. The new biomarkers derived from the dynamic patterns of these proteins' expression provide is a good supplementary method for determining prognosis for CRC, especially for the TNM stage III and IV patients.
authors.affiliation: Department of Digestive Diseases, Hunan Provincial People's Hospital, Hunan Normal University, Changsha, Hunan 410005, China.
authors.forename: Ya
authors.initials: Y
authors.lastname: Peng
authors.forename: Xiayu
authors.initials: X
authors.lastname: Li
authors.forename: Minghua
authors.initials: M
authors.lastname: Wu
authors.forename: Jing
authors.initials: J
authors.lastname: Yang
authors.forename: Minji
authors.initials: M
authors.lastname: Liu
authors.forename: Wengling
authors.initials: W
authors.lastname: Zhang
authors.forename: Bo
authors.initials: B
authors.lastname: Xiang
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Wang
authors.forename: Xiaoling
authors.initials: X
authors.lastname: Li
authors.forename: Guiyuan
authors.initials: G
authors.lastname: Li
authors.forename: Shourong
authors.initials: S
authors.lastname: Shen
mesh_terms: D014408:Biomarkers, Tumor / Q000378:metabolism*; D015153:Blotting, Western; D024401:Carbonic Anhydrase I / Q000378:metabolism; D015179:Colorectal Neoplasms / Q000378:metabolism* / Q000473:pathology*; D021984:Cyclophilin A / Q000378:metabolism; D000091342:Endoplasmic Reticulum Chaperone BiP; D005634:Fructose-Bisphosphate Aldolase / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D011379:Prognosis; D040901:Proteomics / Q000379:methods*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D057825:Two-Dimensional Difference Gel Electrophoresis
chemical_list: D014408:Biomarkers, Tumor; D000091342:Endoplasmic Reticulum Chaperone BiP; C000717247:HSPA5 protein, human; D006360:Heat-Shock Proteins; D005634:Fructose-Bisphosphate Aldolase; D024401:Carbonic Anhydrase I; D021984:Cyclophilin A