AIM To obtain human esophageal cancer cell EC9706 stablyexpressed epithelial membrane protein-1(EMP-1)withintegrated eukaryotic plasmid harboring the open readingframe(ORF)of human EMP-1,and then to study themechanism by which EMP-1 exerts its diverse cellular actionon cell proliferation and altered gene profile by exploringthe effect of EMP-1.METHODS:The authors first constructed pcDNA3.1/myc-his expression vector harboring the ORF of EMP-1 and thentransfected it into human esophageal carcinoma cell lineEC9706.The positive clones were analyzed by Western blotand RT-PCR.Moreover,the cell growth curve was observedand the cell cycle was checked by FACS technique.UsingcDNA microarray technology,the authors compared the geneexpression pattern in positive clones with control.To confirmthe gene expression profile,semi-quantitative RT-PCR wascarried out for 4 of the randomly picked differentiallyexpressed genes.For those differentially expressed genes,classification was performed according to their function andcellular component.RESULTS:Human EMP-1 gene can be stably expressed inEC9706 cell line transfected with human EMP-1.The authorsfound the cell growth decreased,among which S phase wasarrested and G1 phase was prolonged in the transfected positiveclones.By cDNA microarray analysis,35 genes showed anover 2.0 fold change in expression level after transfection,with28 genes being consistently up-regulated and 7 genes beingdown-regulated.Among the classified genes,almost half ofthe induced genes(13 out of 28 genes)were related to cellsignaling,cell communication and particularly to adhesion.CONCLUSION:Overexpression of human EMP-1 gene caninhibit the proliferation of EC9706 cell with S phase arrestedand G1 phase prolonged.The cDNA microarray analysissuggested that EMP-1 may be one of regulators involved incell signaling,cell communication and adhesion regulators. AIM To obtain human esophageal cancer cell EC9706 stablyexpressed epithelial membrane protein-1 (EMP-1) withintegrated eukaryotic plasmid harboring the open readingframe (ORF) of human EMP-1, and then to study themechanism by which EMP-1 exerts its diverse cellular actionon cell proliferation and altered gene profile by exploring the effect of EMP-1.METHODS: The authors first constructed pcDNA3.1 / myc-his expression vector harboring the ORF of EMP-1 and the ntransfected it into human esophageal carcinoma cell lineEC9706.The positive clones were analyzed by Western blot and RT-PCR. Moreover, the cell growth curve was observed and the cell cycle was checked by FACS technique. Using cDNA microarray technology, the authors compared the gene expression pattern in positive clones with control. To confirm the gene expression profile, semi-quantitative RT-PCR was carried out for 4 of the random picked differentially expressed genes. For those differentially expressed genes, classification was performed according to Their function andcellular component .RESULTS: Human EMP-1 gene can be stably expressed inEC9706 cell line transfected with human EMP-1.The authorsfound the cell growth decreased, among which S phasewasarrested and G1 phase was prolonged in the transfected positive clones.By cDNA microarray analysis, 35 genes showed an over 2.0 fold change in expression level after transfection, with 28 genes being consistently up-regulated and 7 genes being down-regulated. Amc the classified genes, almost half of the induced genes (13 out of 28 genes) were related to Cell signaling, cell communication and particularly to adhesion. CONCLUSION: Overexpression of human EMP-1 gene can inhibit the proliferation of EC9706 cell with S phase arrested and G1 phase prolonged. The cDNA microarray analysis suggests that EMP-1 may be one of regulators involved in cell signaling, cell communication and adhesion regulators.