目的:肿瘤差异表达基因在肿瘤的发生发展中起重要作用,胃癌在我国全部恶性肿瘤死亡构成比中居第一位,本文拟钓取人胃癌差异表达基因片段,探讨胃癌发生发展的机制.方法:应用最新分离差异基因的mRNA差异显示技术,优化反应条件对人胃癌组织中差异表达的基因片段进行分离,测序和Northem验证.结果:获得经Northem杂交证实的在胃癌组织中表达的两个cDNA片段scg1和scg2,序列分析表明长度分别为194bp和343bp,同源性比较结果显示scg1和scg2与GenBank中已发表基因序列均无同源性.结论:本研究初步证实scg1和scg2可能是人胃癌组织中表达的新基因片段,推测与人胃癌发生发展相关.检测全长cDNA序列的深入工作正在进行中.

Objective: Identification of the genes specially expressed in tumor cell but not in normal cell is important for understanding the molecular mechanisms of carcinogencsis. This study will focus on identification of differentially expressed gene fragments in human stomach cancer. Methods: By using the new developing mRNA differential display (DD) technique, genes fragments differentially expressed in stomach cancer tissues from a patient and the adjacent normal tissues beyond the tumor mass were studied. Results: Two differentially displayed complementary DNA fragments from stomach cancer tissues, scgl and scg2 (stomach cancer-associated gene, scg), cofirmed by Northern Blot, were cloned and sequenced. The nucleotide length of scgl is 194 base pairs and that of scg2 is 343 base pairs. After searching against GenBank databases by BLASTN, neither scgl nor scg2 had significant homological gene sequences with the known genes. Conclusion: These results suggested scgl and scg2 might be complementary DNA fragments of novel genes expressed in stomach cancer tissues, but not in normal tissues and may play a role in the occurrence and development of stomach cancer. Further characterization of full-length of these two complementary DNA fragments will be continued.

国家青年自然科学基金(No199300145)资助