Elucidation of the mechanisms of liver fibrogenesis is important to treat liver fibrosis.In this study,we established rat models of liver fibrosis with stages from 0–1,2,and 3–4 to 4 at 2,4,6,and 8 weeks,respectively,by injection of pig serum.Liver fibrogenesis was detected by Masson’s trichrome staining.Rat non-parenchymal cells(NPCs)were enriched 4-fold by Percoll density gradient centrifugation.Protein extracts from NPCs were prepared at 4 and 8 weeks,separated by two-dimensional electrophoresis,and then stained with Coomassie Blue G-250.At 4 weeks,we identified 18 non-redundant differentially expressed proteins of which protein disulfide-isomerase associated protein 3(PDIA3)and NDUV showed consistent expression at protein and mRNA levels from 4 to 8 weeks.PDIA3 was found to be down-regulated by Western blotting in the rat model and immunohistochemically in human liver.Our results revealed important aspects of the pathogenesis/progression of liver fibrosis and demonstrated important changes in protein expression levels of NPCs at various stages of liver fibrosis.
Colorectal cancer （CRC） is a leading cause of cancer-related deaths worldwide. We aimed to find novel molecules as potential biomarkers for the early diagnosis of CRC. A serum-free conditioned medium was successfully collected from three pairs of CRC tissue and adjacent normal tissue, iTRAQ-based quantitative proteomic analysis was applied to compare the differences in secretome between primary CRC mucosa and adjacent normal mucosa. A total of 145 kinds of proteins were identified. Of these proteins, 29 were significantly different between CRC and normal tissue. Tropomyosin 2 p （TPM2） exhibited the most significant differences; as such, this protein was selected for further validation. Quantitative real-time PCR indicated that the mRNA expression of TPM2 significantly decreased in the CRC tissue compared with the paired adjacent normal tissue. Immunohistochemical analysis also confirmed that TPM2 was barely detected at protein levels in the CRC tissue. In summary, this study revealed potential molecules for future biomarker applications and provided an efficient approach for the differential analysis of cancer-associated secretome. TPM2 may be valuable for the early diagnosis of CRC.
A non-invasive diagnostic approach is crucial for the evaluation of severity of liver disease,treatment decisions,and assessing drug efficacy.This study evaluated plasma proteomic profiling via an N-terminal isotope tagging strategy coupled with liquid chromatography/Fourier transform ion cyclotron resonance mass spectrometry measurement to detect liver fibrosis staging.Pooled plasma from different liver fibrosis stages,which were assessed in advance by the current gold-standard of liver biopsy,was quantitatively analyzed.A total of 72 plasma proteins were found to be dysregulated during the fibrogenesis process,and this finding constituted a valuable candidate plasma biomarker bank for follow-up analysis.Validation results of fibronectin by Western blotting reconfirmed the mass-based data.Ingenuity Pathways Analysis showed four types of metabolic networks for the functional effect of liver fibrosis disease in chronic hepatitis B patients.Consequently,quantitative proteomics via the N-terminal acetyl isotope labeling technique provides an effective and useful tool for screening plasma candidate biomarkers for liver fibrosis.We quantitatively monitored the fibrogenesis process in CHB patients.We discovered many new valuable candidate biomarkers for the diagnosis of liver fibrosis and also partly identified the mechanism involved in liver fibrosis disease.These results provide a clearer understanding of liver fibrosis pathophysiology and will also hopefully lead to improvement of clinical diagnosis and treatment.
LI ShuLongLIU XinWEI LaiWANG HuiFenZHANG JiYangWEI HanDongQIAN XiaoHongJIANG YingHE FuChu
