Objective:To exclude the disturb of mixed cell types

acquire human esophageal squamous cell carcinoma cells and normal esophageal epithelial cells

analyze the differential expression of proteme between them.Methods:Pure human esophageal squamous cell carcinoma cells and normal esophageal epithelial cells were obtained by LCM

protein were separate by Two dimensional polyacrylamide gel electrophoresis(2-DE)technique

and computer-assisted image analysis were used to analyze the images of polyacrylamide gels.Results:Laser capture microdissection obtained pure objective cells.Analyzed the image of polyacrylamide gels

there were 38 prorein spots that were significantly differentially expressed.Of those 38 protein spots

3 protein spots were newly found

5 protein spots were disappeared

while 20 prorein spots increased markedly

10 prorein spots were decreased significantly.Conclusion:Laser capture microdissection can be apllied to successfully obtain pure objective cells from frozen sections.The proteomic expression in esophageal squamous cell carcinoma cells is significantly different from that of normal esophageal epithelial cells

which may be associated with the mechanism of esophageal carcinogenesis.