Background and purpose:The development of gastric cancer has a long course from chronic mucosal inflammation and involves a lot of genes.We investigated the different gene expression profiles with gene chip of high flux between gastric cancer and chronic atrophic gastritis so as to analyze their biologic significance,combined with endoscopic findings and surgical pathology.Methods:Paired pathological and non-pathological specimens from 23 patients with gastric cancer and 15 with chronic atrophic gastritis were enrolled for the study.Gene chip with 13 824 genes/ESTs was employed for detection of the expression profile,while endoscopic and pathologic findings were collected for evaluation.Data were analyzed by average-linkage hierarchical clustering,t test and Fisher calculation of exact probability.Results:Fifty-three specific genes were filtered from gastric cancer group,and 21 from chronic atrophic gastritis group.In the former group,STS,HAP1 and some other relatively specific genes were expressed in correlation to the Borrmann's classification,while in the latter group,BRD3 and BF508879 were demonstrated positively in correlation to intestinal metaplasia.However,there were also some specific genes,such as SLC26A3,related to precancerous condition,commonly expressed in both two groups.Conclusions:There was either homogenous or heterogeneous gene expression profile in gastric cancer as well as in chronic atrophic gastritis.Abnormal gene expressions were related to precancerous conditions or precancerous lesions and to biologic behavior of tumor.The difference and comparability of gene expression in the two groups studied shows the continuity and pertinence of the two diseases.