Background: Non-small cell lung cancer (NSCLC) is the main type of lung cancer, and the related locus mutation detection research has become a hot direction of molecular targeted therapy, studying on gene mutation status of echinodem microtubule associated protein like 4-Anaplastic lymphoma kinase (EML4-ALK) and epidermal growth factor receptor (EGFR), detecting the sensitivity of EML4-ALK gene fusion and gene mutation of EGFR.
Methods: EML4-ALK gene fusion in 85 cases of paraffin embedded tumor tissue and adjacent lung tissue was detected with the application of immunohistochemistry (IHC), Scorpions amplification refractory mutation system (Scorpions ARMS) fluorescence quantitative PCR and fluorescence in situ hybridization (FISH) technology, and EGFR gene in 18, 19, 20 and 21 exon mutation status was detected with the application of ARMS method.
Results: In 115 cases of NSCLC, IHC showed 32 cases with ALK (D5F3) expression, the expression rate was 27.8%; ARMS showed 27 cases with EML4-ALK fusion gene mutation, the mutation detection rate was 23.5%; 53 cases were detected with EGFR mutation, the mutation rate was 46%. While FISH showed 23 cases with EML4-ALK fusion gene mutation, the detection rate was 20%, slightly lower than the ARMS detection results, suggesting that ARMS more sensitive.
Conclusions: The application of IHC, ARMS fluorescence quantitative PCR and FISH technology can make a rapid and accurate evaluation of EML4-ALK gene fusion.
背景与目的 非小细胞肺癌（non-small cell lung cancer, NSCLC）是肺癌的主要类型，相关位点突变检测研究已经成为肺癌分子靶向治疗的热门方向，研究NSCLC肿瘤组织中动物微管相关蛋白4与间变性淋巴瘤激酶融合基因（echinodem microtubule associated protein like 4-Anaplastic lymphoma kinase, EML4-ALK）与表皮生长因子受体（epidermal growth factor receptor, EGFR）的基因突变状态，比较免疫组织化学（immunohistochemistry, IHC）与蝎形探针扩增阻滞突变系统（Scorpions amplification refractory mutation system, Scorpions ARMS）荧光定量PCR与荧光原位杂交（fluorescence in situ hybridization, FISH）检测EML4-ALK融合基因与EGFR基因突变的敏感性。方法 应用IHC、ARMS荧光定量PCR及FISH技术检测85例NSCLC石蜡包埋肿瘤组织以及癌旁正常肺组织中EML4-ALK融合基因状态，并应用ARMS方法检测EGFR基因第18、19、20和21外显子突变状态。结果 115例NSCLC中IHC显示32例有ALK（D5F3）表达，表达率为27.8%；ARMS检测27例存在EML4-ALK融合基因突变，突变检出率为23.5%；53例检出EGFR突变，突变率为46%。而FISH检测23例存在EML4-ALK融合基因突变，检出率为20%，稍低于ARMS检测结果，提示ARMS的敏感度更高。结论 联合运用IHC/ARMS荧光定量PCR/FISH技术能够对EML4-ALK融合基因状态做出快速、准确评价。