[Gene expression profiling of diffuse-type gastric cancer by cDNA microarray].
OBJECTIVE
To identify cancer-related genes in diffuse-type gastric cancer and to explore its molecular mechanism by cDNA microarray analysis.


METHODS
A total of 22 pairs of diffuse-type gastric cancer tissue and the corresponding normal mucosa were taken and freshly frozen. cDNA microarray with 14,592 genes/ESTs was used. Genes were considered to be up- or down-regulated when the fluorescent intensity ratio between tumor and normal mucosa was over 2-fold in over 50% of the samples (P < 0.05). Hierarchical clustering of regulated genes was performed as a measure to study expressional similarity. Validation of array results was carried out by real time quantitative PCR (QPCR).


RESULTS
Compared with those of corresponding normal mucosa, there were a total of 153 genes/ESTs up-regulated and 204 down-regulated in diffuse-type gastric cancer. Hierarchical clustering demonstrated that the genes belonging to the same subgroup displayed similar function. Most of the overexpressed genes were those related to cell adhesion, cell motility, matrix reconstruction, cell proliferation and/or signal transduction; while genes related to defense response, toxicoid metabolism, DNA repairing, nuclear-cytoplasmic transport and/or anti-apoptosis made up the main list of the underexpressed genes. Seven genes showed higher expression in TNM (T I + T II) group than in (T III + T IV) group. QPCR confirmed the array analysis results.


CONCLUSIONS
Gene expression profiling by cDNA microarray analysis provides not only molecular understanding of biological properties of cancer, but may also be helpful in discovering new diagnostic markers and therapeutic targets in gastric adenocarcinoma.
Zhang
Xiao-qing
XQ
Department of Surgery, Ruijin Hospital, Shanghai Second Medical University, Shanghai 200025, China.
Yang
Yan-qing
YQ
Liu
Bing-ya
BY
Jin
Xiao-long
XL
Li
Wei
W
Tang
Kai-ling
KL
Zhang
Qing-hua
QH
Lin
Yan-zhen
YZ
Zhu
Zheng-gang
ZG
D000230:Adenocarcinoma / Q000235:genetics* / Q000378:metabolism; D058578:Biglycan; D024042:Collagen Type I / Q000378:metabolism; D020224:Expressed Sequence Tags; D016326:Extracellular Matrix Proteins / Q000378:metabolism; D005260:Female; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D008840:Microfilament Proteins / Q000378:metabolism; D008875:Middle Aged; D009124:Muscle Proteins / Q000378:metabolism; D009367:Neoplasm Staging; D020411:Oligonucleotide Array Sequence Analysis; D020115:Pepsinogen C / Q000378:metabolism; D011509:Proteoglycans / Q000378:metabolism; D013274:Stomach Neoplasms / Q000235:genetics* / Q000378:metabolism
C546884:BGN protein, human; D058578:Biglycan; D024042:Collagen Type I; D016326:Extracellular Matrix Proteins; D008840:Microfilament Proteins; D009124:Muscle Proteins; D011509:Proteoglycans; C051615:transgelin; D020115:Pepsinogen C