Preparation of gastric adenocarcinoma related cDNA microarray / 解放军医学杂志

ABSTRACT

Objectives To prepare the gastric adenocarcinoma related cDNA microarray and to screen differentially expressed genes between human gastric adenocarcinoma and normal gastric mucosa. Methods A set of cDNA microarray slides containing a duplicate set of 576 cDNA spots. These selected clones have been verified in sequence. The PCR products of human genes were spotted onto a chemical-material-coated glass plates in array. DNAs were fixed on the glass plate after series of treatment. Both RNAs from the gastric adenocarcinoma and normal gastric mucosa were reversely transcribed to the cDNAs with the incorporation of fluorescent dUTP to prepare the hybridization probes. The mixed probes were hybridized to the cDNA microarray. After high-stringent washing, the cDNA microarray was scanned for fluorescent signals to display differences between two tissues. Results Gastric adenocarcinoma related cDNA microarray slides contained 111 differentially expressed genes of gastric adenocarcinoma, 37 known genes related to gastric carcinogenesis (such as p21ras, p53, etc.) and control genes. The results of 10 couples of hybridizations to the gastric adenocarcinoma related cDNA microarray slides with Cy3-labeled cDNA probe from normal gastric tissue and Cy5-labeled cDNA probe from gastric adenocarcinoma showed analyzed spots uniformity background and clear signal. Among the 576 target genes, the expression level of 48 genes differed between gastric adenocarcinoma and normal mucosa in 5 or more samples (eight genes differed in all samples). There were 39 down-regulated and 9 up-regulated genes in gastric adenocarcinoma. Conclusion Gastric adenocarcinoma related cDNA microarray slides were successfully developed. The results of the experiments showed that gastric adenocarcinoma related cDNA microarray slides are reliable, sensitive and reproducible.