A gene encoding an apurinic/apyrimidinic endonuclease-like protein is up-regulated in human gastric cancer.
OBJECTIVE
To identify the gene that may predispose to human gastric cancer and to analyze its expression in gastric cancer and non-tumorous gastric mucosa.


METHODS
Cancer, para-tumor, and non-tumor gastric tissues were studied for gene expression profile using fluorescent differential display reverse transcription polymerase chain reaction (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-tumor tissues than in their non-tumor counterparts of all 7 tested gastric adenocarcinoma patients was identified by means of DDRT-PCR analysis. It was named GCRG213 (gastric cancer related gene 213). Northern blot confirmed the differential expression. GCRG213 (GenBank No. AY053451) consisted of 1094 base pairs with an open reading frame (ORF) which encoded 142 amino acids. The deduced amino acid sequence contained a putative conserved domain, apurinic/apyrimidinic endonuclease (APE). In situ hybridization analysis showed that GCRG213 was expressed higher in gastric cancer tissues than in their corresponding non-tumor ones. Precancerous leisions of gastric adenocarcinoma showed a high GCRG213 expression, too. No difference of the expression patterns was found between the early and advanced gastric cancer.


CONCLUSIONS
A gene named GCRG213 was identified in human 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.
Wang
Gang-Shi
GS
Department of Gerontal Gastroenterology, General Hospital of Chinese PLA, Beijing 100853, China. wanggangshi@hotmail.com
Wang
Meng-Wei
MW
Wu
Ben-Yan
BY
Liu
Xiao-Bing
XB
You
Wei-Di
WD
Yang
Xin-Yan
XY
D000328:Adult; D000368:Aged; D000595:Amino Acid Sequence / Q000235:genetics; D001483:Base Sequence / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D004720:Endonucleases / Q000235:genetics*; D005260:Female; D006801:Humans; D017403:In Situ Hybridization; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D036361:Peptide Hormones; D012333:RNA, Messenger / Q000378:metabolism; D013274:Stomach Neoplasms / Q000235:genetics* / Q000378:metabolism; D015854:Up-Regulation
D018076:DNA, Complementary; C477000:GKN1 protein, human; D036361:Peptide Hormones; D012333:RNA, Messenger; D004720:Endonucleases