AIM:To reveal new tumor markers and target genes fromdifferentially expressed genes of primary tumor samplesusing cDNA microarray.METHODS:The ~(33)P labeled cDNAs were synthesized byreverse transcription of message RNA from the livercancerous tissue and adjacent non-cancerous liver tissuefrom the same patient and used to hybridize to LifeGrid 1.0cDNA microarray blot containing 8400 known and uniquehuman cDNA gene targets,and an expression profile ofgenes was produced in one paired human liver tumor tissue.After a global analysis of gene expression of 8400 genes,we selected some genes to confirm the differential expressionusing Northern blot and RT-PCR.RESULTS:Parallel analysis of the hybridized signals enabledus to get an expression profile of genes in which about 500genes were differentially expressed in the paired liver tumortissues.We identified 4 genes,the expression of three(Beclin1,RbAp48 and Pir51) were increased and one (aldolase b)was decreased in liver tumor tissues.In addition,theexpression of these genes in 6 hepatoma cell lines was alsoshowed by RT-PCR analysis.CONCLUSION:cDNA microarray permits a high throughputidentification of changes in gene expression.The genesencoding Beclin 1,RbAp48,Pir51 and aldolase b are firstreported that may be related with hepatocarcinoma. AIM: To reveal new tumor markers and target genes from differentially expressed genes of primary tumor samples using cDNA microarray. METHODS: The ~ (33) P labeled cDNAs were synthesized by reverse transcription of message RNA from the liver cancer tissue and adjacent non-cancerous liver tissue from the same patient and used to hybridize to LifeGrid 1.0 cDNA microarray blot containing 8400 known and uniquehuman cDNA gene targets, and an expression profile of genes was produced in one paired human liver tumor tissue. After a global analysis of gene expression of 8400 genes, we selected some genes To confirm the differential expression by Northern blot and RT-PCR .RESULTS: Parallel analysis of the hybridized signals enabledus to get an expression profile of genes in which about 500genes were differentially expressed in the paired liver tumorum. We identified 4 genes, the expression of three (Beclin1, RbAp48 and Pir51) were increased and one (aldolase b) was decreased in liver tumor tissues. In additi on, theexpression of these genes in 6 hepatoma cell lines was alsoshowed by RT-PCR analysis.CONCLUSION: cDNA microarray permits a high throughputidentification of changes in gene expression. The genesencoding Beclin 1, RbAp48, Pir51 and aldolase b are firstreported that may be related with hepatocarcinoma.