【摘要】 目的为探明中国人胃癌的微卫星ＤＮＡ的不稳定性（ｍｉｃｒｏｓａｔｅｌｉｔｅｉｎｓｔａｂｉｌｉｔｙ，ＭＳＩ）频率。方法选择了２９个多态微卫星标记，采用ＰＣＲ－聚丙烯酰胺凝胶电泳及银染技术对４２例胃癌组织进行了ＭＳＩ分析。结果中国人胃癌，在２９个位点上平均ＭＳＩ频率为３３．９％。在Ｄ３Ｓ１０６７、Ｄ３Ｓ１５７７、Ｄ８Ｓ２７９、Ｄ９Ｓ２５７、Ｄ１Ｓ２４８、Ｄ７Ｓ５２０及Ｄ２Ｓ１４７等位点上存在高频率的ＭＳＩ，其中Ｄ３Ｓ１５７７和Ｄ３Ｓ１０６７（５１．３５％）ＭＳＩ发生频率最高。胃癌的不同病理类型表现出不同的ＭＳＩ。低分化胃癌和印戒细胞癌与高分化癌比，ＭＳＩ频率明显增高（Ｐ＜０．０１）；而低分化胃癌和印戒细胞癌之间ＭＳＩ无显著差异（Ｐ＞０．０５）。结论ＭＳＩ在中国人胃癌中起着重要作用，尤其在低分化胃癌中。这些资料进一步证明，高低分化的胃癌可能具有不同的发病机理更多还原

【Abstract】 Objective To identify the microsatellite instability (MSI) rates in Chinese gastric cancer samples. Methods 29 microsatellite markers were selected to examine 42 paired gastric cancer tissues for MSI on all chromosomes except Y. Results The total frequency of MSI in all 42 gastric cancers was 33.9% with higher rates at loci of D3S1577, D3S1067, D8S279, D9S257, D1S248, D7S520 and D2S147, and the highest rate at D3S1577 and D3S1067(51.35%). MSI varied with different pathological types. The frequencies of MSI were significantly higher in poorly differentiated tumors and signet cell types, compared with well differentiated tumors ( P =0.0026 and 0.0013 by chi square test), and no difference was noted between poorly differentiated and signet cell types. Conclusion MSI may play an important role in Chinese gastric cancer, particularly the poorly differentiated adenocarcinomas. The data presented here further support the previous hypothesis that pathologically distinct subtypes of gastric cancer undergo different genetic pathways during tumorigenesis.更多还原