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Objective@#To search for biomarkers for human familial prion disease.@*Methods@#Two-dimensional differential gel electrophoresis (2D-DIGE) proteomic analysis has been performed in frontal lobe tissues of 3 patients suffering from human familial prion disease (PrP) and 3 age-and sex-matched patients suffering from sudden death due to heart failure without neurological disease.@*Results@#The maps revealed 14 polypeptide chains differentially modulated in the PrP samples, among those, 7 could be identified upon digestion and MALDI-TOF/MS analysis, of which 6 appeared to be up-regulated, 1 being down-regulated.@*Conclusions@#We highlight Galectin-1(Gal-1), ryanodine receptor 2 (RyR2), ubiquitin, Rab-interacting lysosomes protein-like protein 1 (RILPL-1) profillin 2 (PFN2), in the differential map. These proteins are related to neurogenesis, the clearance of misfolded proteins, stasis of calium channel, myoclonus and so on. These proteins are potential biomarkers or targets for treatment of prion disease.
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Objectives To screen the differentially expressed proteins in serum of population chronically exposed to arsenic in drinking water,thus to provide candidate protein biomarkers for arsenic exposure and arsenicosis.Methods Subjects were selected from the drinking water type of endemic arsenicosis areas in Shanxi province,China.Demographic characteristics,history of arsenic exposure,cigarette smoking,alcohol drinking,health and other information were collected using questionnaire.The subjects were divided into low-arsenic group (with arsenic in drinking water ＜ 10 μg/L),medium-arsenic group( 10 - 50 μg/L),high-arsenic group( ＞ 50 μg/L),and arsenicosis group(the drinking water with arsenic ＞ 50 μg/L was replaced by low arsenic water ＜ 10 μg/L).The number of cases in each group was 30.The arsenicosis patients were diagnosed according to “Standard of Diagnosis for Endemic Arsenism” (WS/T 211-2001 ).With the principle of informed consent,blood samples were collected.Differentially expressed serum proteins of different arsenic exposure groups and arsenicosis group were screened by two-dimensional differential gel electrophoresis(2-D DIGE),and further identified by mass spectrometry (MS).Results An average of (1299 ± 167) protein spots were identified in 6 gel images and 688 protein spots were discovered repeatedly in at least 5 gels.There were 33 protein spots differentially expressed among low-,medium- and high-arsenic groups P ＜ 0.01).Fifty four protein spots were significantly different among low-,medium-,high-arsenic exposure groups and arsenicosis group(P ＜ 0.01 ).Twenty five protein spots were selected for MS analysis,and13 protein spots were identified.Compared with low-arsenic group,the expressions of apolipoprotein A-Ⅳ,retinol binding protein,and estrogen receptor hypothalamic isoform in medium- and higharsenic exposure groups were down regulated,and the expressions of component 4A and 4B were up regulated.Compared with low-,medium- and high-arsenic groups,the expressions of beta-2-glycoprotein Ⅰ,Keratin 1,hemopexin,complement C1r subcomponent,and ficolin-3 in arsenicosis group were down regulated,and the expressions of pigment epithelial-differentiating factor,alpha-1-microglobulin and carboxypeptidase N catalytic chain were up regulated.Conclusions Chronic arsenic exposure can significantly change population's serum protein expression.Differentially expressed proteins in arsenicosis patients will not decline with the decline of arsenic in a short term.Whether or not the differentially expressed proteins identified in this study can be used as biomarkers for arsenic exposure and arsenicosis needs to be further verified.
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ObjectiveA comparative proteomic method was used to analyse serum proteins between pancreatic cancer patients and control group,and to find a new protential specific marker.MethodsComparative analysis on the pancreatic peripheral blood protein profiling from 40 pancreatic cancer patients,10 chronic pancreatitis patients,10 benign tumor patients and 40 cancer-free controls was carried out by 2D differential gel electrophoresis,and differentially expressed proteins were identified by matrix-assisted laser desorption/ionization time of flight mass spectrometry.ResultsTwo differentially expressed proteins:transthyretin and apolipoprotein E were identified.Those proteins were highly expressed in pancreatic carcinoma group compared with normal control group,chronic pancreatitis group and benign tumor group.Conclusion2D differential gel electrophoresis and matrix-assisted laser desorption/ionization time of flight mass spectrometry technology in screening specific serum biomarkers of pancreatic cancer has a well repeatability and stability.The identified protein transthyretin in this study may be as specific serum biomarkers of pancreatic carcinoma.
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Objective: To investigate differentially expressed protein profiles in B16-F10 grafted melanoma and its metastasis in the lung in order to identify molecular markers of melanoma metastasis. Methods: Differentially expressed proteins in B16-F10 grafted melanoma and its metastatic lesion in the lung were isolated and identified by fluorescence two-dimensional differential gel electrophoresis(2D-DIGE)coupled with matrix assisted laser desorption ionisation time-of-flight mass spectrometry(MALDI-TOF-MS).Some of identified proteins were further confirmed by Real-time PCR analysis. Results: High resolutional images of differential gel electrophoresis were obtained and 9 of 30 differentially expressed proteins (IRatiol≥2,P<0.01)were identified by MALDI-TOF-MS.The expression of Myoglobin(MB),vimentin(VIM),phosphoglycerate kinase 1(PGK1),Triosephosphate isomerase(TPI or TIM),heavy-chain binding protein(BiP),α-enolase,β-actin,γ-actin,and laminin-binding protein were up-regulated in the experimental group compared with the control group.These proteins were involved in the cytoskeletal formation,glycolysis and so on.Real-time PCR analysis showed up-regulation of mRNA expression of PGK1 and TPI in the experimental group(P=0.001 and 0.003),which was in consistent with the resuits of proteomic analysis. Conclusion: A variety of abnormally expressed proteins contribute to the metastasis of mice melanoma.Glycolytic enzymes PGK1 and TPI may be involved in this process.