Screening differentially expressed genes in gastric adenocarcinoma by cDNA microarray

Objective: To search for the differentially expressed genes between gastric adenocarcinoma and normal gastric mucosa using cDNA microarray. Methods: The PCR products of 12 800 human genes were spotted on a chemical material coated glass plate in array. DNAs were fixed onto the glass plate after series of treatments. The total RNAs were isolated from the tissues, and were purified to mRNAs by Oligotex. Both mRNAs 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 the fluorescent signals and showed differences between 2 tissues. Results: Among the 12 800 target genes, 27 genes differentially expressed in all 5 samples were identified, 11 were up regulated (0.086%) and 16 down regulated (0.125%). There were 2 novel genes among the down regulated group. Conclusion: cDNA microarray technique is effective in screening the differentially expressed genes between gastric adenocarcinoma and normal gastric mucosa. [