中文摘要：

目的：利用MassARRAY分子量阵列分析系统检测胃癌组织PIK3CA基因突变。方法：从胃癌石蜡包埋组织中提取基因组，PCR反应扩增目的基因片段，MassARRAY分子量阵列分析系统检测PIK3CA基因突变；焦磷酸测序验证检测结果。结果：中国西部地区144例胃癌组织样本中PIK3CA_E542K（1624G〉A）突变携带率为77．6％，PIK3C_LIE545K（1633G〉A）突变携带率为84％。MassARRAY分子量阵列分析系统检测结果与焦磷酸测序结果达到100％吻合。结论：建立了MassARRAY分子量阵列分析系统检测基因突变的方法，初步建立了中国西北地区汉族人群胃癌组织PIK3CA基因PIK3CA_E542K（1624G〉A）PIK3CA_E545K（1633G〉A）位点突变频数。

英文摘要：

To investigate the PIK3CA gene mutation by MALDI-TOF mass spectrometry method （MassARRAY）. Methods： Genomic DNA was extracted from paraffin embedding gastric cancer tissues. Targeted PIK3CA gene fragments were amplified by PCR. The remaining and nonincorporated dNTPs were removed from amplification products by Shrimp alkaline phosphatase（SAP）. Mass spectrometry detection was carried out after primer extension reaction and primer extension reaction cleanup. Results： In 144 paraffin embedding gastric cancer tissues were detected, the mutation ratio ofPIK3CA_E542K（1624G〉A） was 77.6%, and the mutation ratio of PIK3CA_E545K （1633G 〉A） was 84%. All PIK3CA mutation results were the same as pyrosequencing results. Conclusion： The MAL_ DI-TOF mass spectrometry method for PIK3CA mutation detection was successfully established. The mutation frequencies of PIK3CA_E542K （1624G〉A） and PIK3CA_E545K （1633G〉A） of gastric cancer have primarily been set up and this fotmding is only con-cerning with people of Han nationality among nor-thwest China.