The Study On Differentially Expressed Proteins Of Esophageal Squamous Cell Carcinoma

Esophageal squamous cell carcinoma (ESCC) is one of the six most commonmalignant diseases in the world. Esophageal squamous cell carcinoma (ESCC) is themost prevalent type of esophageal cancer in China compared to adenocarcinoma inWestern countries. Although a lot of researches had been Performed on esophagealeareinoma, the5-yearsurvival for ESCC patients who underwent operation remains aslow as25%or even less. The reasons for this disappointingly low survival rate are thelack of sensitive and specific biomarkers for early detection and effective targets fortreatment.Recent studies on the molecular biology of tumors have revealed that thetumorigenesis and development of esophageal cancer is a complex biological process,involving a variety of genes and factors. Most of the researches have been focused ongene level for early diagnosis of ESCC. However, because alterations in DNA andRNA may or may not Lead to similar protein changes, genetic changes could not trulyreflect the stage and progression of the disease. Proteomics based on two-dimensionalelectrophoresis and mass spectrometry provides a new method for screeningcancer-specific protein markers.The objective of this study was to report a comparative analysis proteinexpression profiles in human ESCC tissues and adjacent normal tissues usingtwodimensional electrophoresis (2DE) and matrix-assisted laserdesorption/ionization-time-of flight mass spectrometry (MALDI-TOF MS) analysis,and to identify the Proteins involved in the esophageal carcinoma carcinogenesis andbiomarkers associated with diagnosis and prognosis.Material and methods:Proteins extracted from ESCC tissues and adjacent normal tissues in10case were separated by two-dimensional gel electrophoresis(2-DE). In the second dimensionalelectrophoresis Isoelectric focusing electrophoresis (IEF) was performed using24-cmIPG drystrips (pI range,3-5.6; Amersham Biosciences), and in the seconddimensional electrophoresis12.5%SDS-PAG was used. The analytical gels wereobtained after coomassie-blue staining. The stained gels were scanned byImagescanner, and ImageMaster2D Platinum7.0Software analyse the image. Thedifferential spots were excised from preparative gel, MS analysis was carried outusing matri-assisted laser desorption/ionization time of flight massspectrometry(MALDI-TOF-MS)and tandem mass spectrometry(TMS).Result1.The average of protein spots of tumor tissues were834士32,and the averagematched spots were729±34for the tumor tissues, The average of protein spots andthe average matched spots were802土29and715±24for the adjacent normal tissues.2.A total38protein spots were analyzed to be differentially expressed，22proteinswere down-regulated and16proteins were up-regulated in esophageal carcinoma.26proteins were identified by MALDI-TOF-MS/MS.ConclusionThe well-resolved, reproducible2-DE patterns of human ESCC tissues and adjacentnormal tissues were established. a number of differentially expressed proteins wereidentified. these identified proteins might play a vital role in process of esophagealcell differentiation and carcinogenesis, Some of identified differentially expressedproteins could be used as biomarkers in esophageal cancer diagnosis.