Comparative proteomic study at the different stages during initiation and evolution of experimental colorectal carcinoma / 肿瘤

ABSTRACT

Objective: To research the proteins differentially expressed during evolution of experimental colorectal carcinoma (normal mucosa→adenoma→carcinoma→liver metastasis) so as to find the early diagnostic biomarker of colorectal cancer as well as to understand its pathogenesis mechanism. Methods: Ninety male rats were injected with 1, 2-dimethylhydrazine intraperitoneally and sacrificed at different weeks to establish the experimental colorectal tumor models (from normal mucosa to liver metastasis). These samples at different stages were collected and divided into four groups (normal mucosa group, adenoma group, carcinoma group, and liver metastasis group). The proteins of these 4 groups were extracted to conduct 2-dimensional gel electrophoresis. The differential protein spots were examined by mass spectrometry and analyzed by bioinformatics. Results: Ten differentially expressed proteins were identified by 2-dimensional gel electrophoresis and mass spectrometry including α-enolase, cardiac α-actin (CA), transgelin protein, myosin regulatory light chain smooth muscle isoform (MRLC), glyceraldehydes-3-phosphate dehydrogenase (GAPDH), haptoglobin, disulfideisomerase (DI), creatine kinase mitochondrial (CKm), heat shock protein-8 (HSP-8) and Keratin complex-2 (KC-2). Conclusions: There exist differentially expressed proteins at various stages during the evolution of colorectal carcinoma. These proteins may be the candidate biomarkers for the early diagnosis of colorectal carcinoma. Proteomic technology is an effective way for preliminary identification of the tumor biomarkers.