High-abundance proteins proteins in the serum were removed by immune-chromatography assay, Isobaric tags for relative and absolute quantitation (iTRAQ) coupled with two-dimensional liquid chromatography/tandem PXD101 concentration mass spectrometry (2D-LC-MS/MS) were used to analyze and identify the proteins expression of between four groups. The samples of intestinal metaplasia group, dysplasia group, gastric cancer group and normal control group were labeled with

iTRAQ reagent 117, 119, 116, and 118, respectively. The samples were detected by cation exchange chromatography (SCX) and reversed phase chromatography (RP), Protein Pilot 4.2 were used to deal with the results of peptides mass spectrometry, and qualitative

and quantitative identified various protein. Serum differential proteins involving in the genesis and development of gastric cancer were screened, ratio >1.6 or ratio <0.625 and P-Value < 0.05 as an approximate benchmark for variation in protein expression. Bioinformatics was used to analysed the serum differential proteins. Results: This iTRAQ coupled with 2D-LC-MS/MS proteomics analysis led to the identification of a total of 10540 unique peptides, which correspond to a set of 199 RG7420 research buy proteins. ratio >1.6 or ratio <0.625 and P-Value < 0.05 as an approximate benchmark for variation in protein expression. Compared with normal control population, seventeen serum differential proteins, including twelve proteins expression were up- regulated and five proteins expression medchemexpress were expression were down-regulated in gastric cancer patients were screened; two serum differential proteins were up- regulated in dysplasia patients were screened; eight serum differential proteins, including seven proteins expression were up-regulated and one proteins expression were expression were down-regulated in intestinal metaplasia

patients; one serum differential proteins was up-regulated both in gastric cancer patients and dysplasia patients; one serum differential proteins was up- regulated and one serum differential proteins was down-regulated both in gastric cancer patients and intestinal metaplasia patients; one serum differential proteins was up- regulated both in dysplasia patients and intestinal metaplasia patients, whereas there was any serum differential proteins was screened between this there types of patients. According to the biological function, all of the differential proteins were comprised immune related protein, lipid transport and metabolism protein, transportation and storage protein, cell adhesion and movement protein, energy metabolism and coagulation-related protein.