[Gene expression profile of human adenocarcinoma by cDNA microarray and clustering].
OBJECTIVE
To investigate the gene expression profile of human gastric adenocarcinoma by means of cDNA microarray and to analyze its biological significance.


METHODS
Paired tumor and non-tumor specimens from 18 cases of advanced gastric adenocarcinoma were studied. Total RNA was isolated and labeled by reverse transcription reaction with cy5 and cy3 for cDNA probe. cDNA microarrays containing 148 genes were hybridized with labeled cDNA probe. Data from cDNA microarray experiments were analyzed by average-linkage hierarchical clustering and significance analysis of microarrays (SAM).


RESULTS
Eighteen tumor and non-tumor specimens were clearly divided by clustering analysis. Three features of gene expression profile were found in gastric adenocarcinoma and non-tumor tissues. The profile of differential gene expression in tumor and non-tumor tissues was mainly shown in feature B and feature C. In gastric adenocarcinoma tissues, the expression of genes in feature B was lower and that in feature C was higher. The profile of differential gene expression among gastric adenocarcinoma tissues was found in feature A. In feature A, the profile of similar gene expression was found in paired tumor and non-tumor tissues from 13 patients. SAM analysis showed that 19 genes in feature B and 12 genes in feature C were of significant difference between tumor and non-tumor specimens. The expression levels of genes related to cell cycle, growth factor, cell adhesion, and matrix remodeling were higher or lower in gastric adenocarcinoma tissues.


CONCLUSIONS
Data from cDNA microarray experiments can clearly distinguish gastric adenocarcinoma from non-tumor tissues. The profiles show that gene expression in gastric adenocarcinomas is both homogeneous and heterogeneous. The homogeneous gene expression profile is found in both tumor and non-tumor tissues from 13 patients, suggesting that some gene aberrance is an early event of carcinogenesis of gastric adenocarcinoma. This study provides not only a new molecular basis for understanding biological properties of gastric adenocarcinoma, but also useful resources for future development of diagnostic and prognostic markers for gastric adenocarcinoma.
Shao
Yong
Y
Department of Elderly Gastroenterology, General Hospital of Chinese PLA, Beijing, 100853 PR China. shaoy62@hotmail.com
Yang
Shao-bo
SB
Wang
Meng-wei
MW
Wu
Ben-yan
BY
You
Wei-di
WD
Li
Hong
H
D000230:Adenocarcinoma / Q000235:genetics*; D000328:Adult; D000368:Aged; D016000:Cluster Analysis; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D008297:Male; D008875:Middle Aged; D020411:Oligonucleotide Array Sequence Analysis; D013274:Stomach Neoplasms / Q000235:genetics*