AIM:To identify the gene that may predispose to humangastric cancer and to analyze its expression in gastric cancerand non-tumorous gastric mucosa.METHODS:Cancer,para-tumor,and non-tumor gastrictissues were studied for gene expression profile usingfluorescent differential display reverse transcriptionpolymerase chain reaction (DDRT-PCR).The differentiallyexpressed bands of interest were analyzed by cloning,Northern blotting,and sequencing.The sequencing resultswere compared with the GenBank database for homologyand conserved domain analysis.In situ hybridization withDIG-labeled cRNA probes was used to detect the expressionof gene in paraffin embedded gastric adenocarcinoma andnon-cancerous tissues.RESULTS:A gene expressed higher in tumor and para-tumortissues than in their non-tumor counterparts of all 7 testedgastric adenocarcinoma patients was identified by means ofDDRT-PCR analysis.It was named GCRG213 (gastric cancerrelated gene 213).Northern blot confirmed the differentialexpression.GCRG213(GenBank No.AY053451) consisted of1094 base pairs with an open reading frame (ORF) whichencoded 142 amino acids.The deduced amino add sequencecontained a putative conserved domain,apurinic/apyrimidinicendonuclease (APE).In situ hybridization analysis showedthat GCRG213was expressed higher in gastric cancer tissuesthan in their corresponding non-tumor ones.Precancerousleisions of gastric adenocarcinoma showed a high GCRG213expression,too.No difference of the expression patterns wasfound between the early and advanced gastric cancer.CONCLUSION:A gene named GCRG213was identified inhuman gastric adenocarcinoma.It encoded an APE-likeprotein which was probably a new member of the APE family.GCRG213 was over-expressed not only in gastric cancer,but also in its precancerous leisions.The role of GCRG213expression in carcinogenesis needs further study. AIM: To identify the gene that may predispose to humangastric cancer and to analyze its expression in gastric cancerand non-tumorous gastric mucosa. METHODS: Cancer, para-tumor, and non-tumor gas strictissues were studied for gene expression profile using fluid differential display reverse transcription polymerase chain DDRT-PCR. The differentially expressed bands of interest were analyzed by cloning, Northern blotting, and sequencing. The sequencing results were compared with the GenBank database for homology and conserved domain analysis. In situ hybridization with dig-labeled cRNA probes was used to detect the expression of gene in paraffin embedded gastric adenocarcinoma and non-cancerous tissues. RESULTS: A gene expressed higher in tumor and para-tumortissues than in their non-tumor counterparts of all 7 testedgastric adenocarcinoma patients was identified by means of DDT-PCR analysis. It was named GCRG213 (gastric cancer related gene 213). Northern blot confirmed the differentialexpressi (GenBank No.AY053451) consisted of 1094 base pairs with an open reading frame (ORF) whichencoded 142 amino acids. The deduced amino add sequencecontained a putative conserved domain, apurinic / apyrimidinicendonuclease (APE) .In situ hybridization analysis showedthat GCRG213was expressed higher in gastric cancer tissuesthan in their corresponding non-tumor ones. Pessationrousles of gastric GAPG213 expression, too. Difference of the expression patterns was found between the early and advanced gastric cancer. CONCLUSION: A gene named GCRG213was identified inhuman gastric adenocarcinoma. It encoded an APE-like protein which was probably a new member of the APE family. GCRG213 was over-expressed not only in gastric cancer, but also in its precancerous leisions. The role of GCRG213 expression in carcinogenesis needs further study.