基因表达谱芯片在筛选胃腺癌相关基因中的应用

目的：应用基因表达谱芯片筛选胃腺癌相关基因，并对这些基因的功能进行初步分析。方法：按一步法抽提胃腺癌和对照胃（正常）组织的RNA并纯化mRNA；将12800条人类基因PCR产物按微矩阵排列点样于化学涂层的载玻片上，制成基因芯片；将等量的对照胃和胃腺癌组织mRNA分别逆转录合成荧光分子掺入的cDNA一链做探针，混合后杂交上述基因芯片。经严格洗片后扫描荧光信号图像，计算机分析后比较两种组织中差异表达的基因。结果：在12800条基因中，胃腺癌与正常胃组织间存在差异表达的基因。在所检测的5例临床标本中均存在显差异表达的基因共27条（0．21％），其中上调的11条（0．086％），下调的16条（0．125％），下调的基因中有2条为新基因。结论：微矩阵基因芯片在筛选胃腺癌发生相关基因的改变时、具有快速、高通量、高敏度等特点，胃腺癌基因差异表达谱的分析为胃癌的诊治提供了新的思路和线索。

Screening differentially expressed genes in gastric adenocarcinoma by cDNA micro array

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. [