Screening And Identification Of Gastric Carcinoma Associated Antigens And Serum Biomarkers By Immunoproteomics

BACKGROUND & OBJECTIVE:Tumor associated antigens may be potential tumor markers.It's important to globally identify tumor associated antigens. This study identify tumor associated antigens and protein biomarker of gastric carcinoma by using Immunoproteomics .METHODS:Fifteen paired samples of gastric carcinoma tissue and corresponding nontumorous gastric tissue as well as normal gastric tissue samples were used in the study. Immunoproteomics technique was used. Tissue proteins were separated by 2-DE, transferred onto PVDF membranes, and immunoblotted with autologous sera. By comparing each immunoblot pattern, The Western blot imaging films were obtained and the differential reacting protein spots were recognized, then the differential reacting protein spots in the replica gel were identified by MALDI-TOF mass spectrometric analysis with relative software.RESULTS:1. The results showed that well-resolved, reproducible 2-DE imaging films of human gastric carcinoma tissues were obtained.The number of average spots of 15 gels was 839±24.There were 752±21 spots matched.The average match rate was 89.6%.2. Well-resolved 2-DE western imaging films of human gastric carcinoma and corresponding nontumorous gastric tissue as well as normal gastric tissue reacted with patient autologous sera were obtained. We identified seventeen immunoreactive spots with stronger staining intensity in tumorous tissues than in corresponding nontumorous tissues and in normal gastric tissues. Matched proteins on 2-DE gels were identified by MALDI-TOF mass spectrometric analysis, These immunoreactive proteins were Manganese superoxide dismutase(Mn-SOD), Biliverdin reductaseB(BVRB), Alpha enolase,Enolase 1,6-phosphogluconolactonase, Vimentin variant,Nuclear mitotic apparatus protein 1 variant,Heat shock protein 27(HSP27), F-actin capping protein alpha-1 subunit, Glyceraldehyde-3-phosphate dehydrogenase,Tubulin beta 5,Fibrinogen beta chain preproprotein,Aldehyde dehydrogenase 9A1,Guanine nucleotide-binding protein beta-2 subunit,Chain L,mature oxy-cope catalytic antibody with hapten, Calponin 1 basic smooth muscle. Some proteins mediate cell growth and metabolism, and others involve in the regulation of cell cycle and signal transduction.CONCLUSION:1. Well-resolved, reproducible 2-DE imaging films of human gastric carcinoma tissues were obtained. 2. Well-resolved 2-DE western imaging films of human gastric carcinoma and corresponding nontumorous gastric tissue as well as normal gastric tissue reacted with patient autologous sera were obtained.3. We identified identified seventeen gastric carcinoma-associated antigens with tumor-specific humoral immune responses in gastric carcinoma.4. These results may provide scientific foundation for screening the molecular biomarker used to diagnose and treat gastric carcinoma, as well as to elevate the patient's prognosis and provide new clue for the research of gastric carcinoma.