肺癌中EML4-ALK融合基因的存在状态及生物学功能

肺癌是当前世界上最常见的恶性肿瘤,主要包括小细胞肺癌(small cell lung cancer,SCLC)和非小细胞肺癌(non-small cell lung cancer,NSCLC)两类,而NSCLC约占肺癌总数的80%。尽管外科手术技术不断提高,化疗新药不断上市并进入临床应用,但肺癌患者的预后仍     

EML4-ALK融合基因在非小细胞肺癌中的临床意义

世界范围内肺癌位居所有癌症致死的第一位,其中大多数为非小细胞肺癌(non-small cell lung cancer,NSCLC)。目前,分子靶向治疗是NSCLC的治疗中最有发展前景的部分。近年来,NSCLC新的分子生物靶点例如棘皮动物微管相关类蛋白4与间变性淋巴瘤激酶融合基因越来越受到关注。本文旨在介绍EML4-ALK融合基因的基本结构、临床病理学特征、检测方法、ALK抑制剂及其在NSCLC治疗中的意义。     

Evaluation of EML4-ALK Fusion Proteins in Non-Small Cell Lung Cancer Using Small Molecule Inhibitors

The echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK) fusion gene resulting from an inversion within chromosome 2p occurs in approximately 5% of non-small cell lung cancer and is mutually exclusive with Ras and EGFR mutations. In this study, we have used a potent and selective ALK small molecule inhibitor, NPV-TAE684, to assess the oncogenic role of EML4-ALK in non-small cell lung cancer (NSCLC). We show here that TAE684 inhibits proliferation and induces cell cycle arrest, apoptosis, and tumor regression in two NSCLC models that harbor EML4-ALK fusions. TAE684 inhibits EML4-ALK activation and its downstream signaling including ERK, AKT, and STAT3. We used microarray analysis to carry out targeted pathway studies of gene expression changes in H2228 NSCLC xenograft model after TAE684 treatment and identified a gene signature of EML4-ALK inhibition. The gene signature represents 1210 known human genes, and the top biologic processes represented by these genes are cell cycle, DNA synthesis, cell proliferation, and cell death. We also compared the effect of TAE684 with PF2341066, a c-Met and ALK small molecule inhibitor currently in clinical trial in cancers harboring ALK fusions, and demonstrated that TAE684 is a much more potent inhibitor of EML4-ALK. Our data demonstrate that EML4-ALK plays an important role in the pathogenesis of a subset of NSCLC and provides insight into the mechanism of EML4-ALK inhibition by a small molecule inhibitor.     

非小细胞肺癌EML4-ALK融合基因的检测及临床应用进展

分子靶向治疗是目前最具前景的研究领域,而融合基因分子靶点检测是分子靶向治疗的前提.EML4-ALK融合基因是新近发现主要表达于非小细胞肺腺癌中,可能与非小细胞肺癌表皮生长因子受体酪氨酸激酶抑制剂(EGFR-TKI)耐药相关,文章就其发现过程以及临床应用进行综述.     

EML4-ALK抑制剂在非小细胞肺癌中发生耐药的机制

非小细胞肺癌(non-small cell lung cancer,NSCLC)约占肺癌总数的80%-85%,是最常见的恶性肿瘤之一。继表皮生长因子受体(epithelial growth factor receptor,EGFR)基因突变在NSCLC发生过程中的机制逐渐明晰后,NSCLC的靶向治疗已经成为临床实践的热点[1]。近年来的研究[2]发现了一种新的癌基因,棘皮动物微管相     

免疫组化法检测EML4-ALK融合突变价值的meta分析

背景与目的 棘皮动物微管相关蛋白4(echinoderm microtubule-associated protein 4,EML4)与间变性淋巴瘤激酶(anaplastic lymphatic tumor kinase,ALK)重排形成的融合基因存在于大约5％的非小细胞肺癌(non-small cell lung cancer,NSCLC)患者中,是继表皮生长因子受体(epidermal growth factor receptor,EGFR)、K-ras之后又一新型靶点基因.有数据显示携带EML4-ALK融合基因的NSCLC患者接受ALK抑制剂治疗后,其疾病控制的有效率可达80％,探索和建立能够准确快速检测出NSCLC患者EML4-ALK融合突变的方法,是筛选出适合治疗的优势人群的关键.本研究分析免疫组化法(immunohistochemistry,IHC)检测EML4-ALK融合基因突变的敏感度与特异度,评价该方法准确性及临床应用价值,从而为肺癌患者“个体化分子治疗”提供依据.方法 通过Pubmed数据库检索所有符合检索条件的文献,末次检索日期为2015年2月25日,根据纳入和排除标准进行进一步筛选,采用诊断试验meta分析方法,比较特异性抗体免疫组化法与“金标准”荧光原位杂交(fluorescence in situ hybridization,FISH)法的敏感度、特异度,以明确特异性抗体IHC作为筛查方法的可行性.结果 本文11篇文献纳入meta分析,EML4-ALK融合基因免疫组化累计病例3,234例,诊断比值比(diagnositic odds ratio,DOR)为1,135.00(95％CI:337.10-3,821.46);综合受试者工作特征曲线(summary receiver operating characteristic curve,SROC)下面积为0.992,3(SEAUC=0.003,2),Q*统计量为0.964,4(SEQ*=0.008,7).结论 特异性抗体IHC法检测EML4-ALK融合基因的方法可行,具有高特异度和敏感度,可作为一种简单快速的筛查方法,具有临床应用价值.     

A Pooled Analysis on Crizotinib in Treating Chinese Patients with EML4-ALK Positive Non-small-cell Lung Cancer

Background: This analysis was conducted to evaluate the efficacy and safety of crizotinib based regimens intreating Chinese patients with EML4-ALK positive non-small-cell lung cancer. Materials and Methods: Clinicalstudies evaluating the efficacy and safety of crizotinib based regimens on response and safety for Chinese patientswith EML4-ALK positive non-small-cell lung cancer were identified by using a predefined search strategy.Pooled response rate (RR) of treatment were calculated. Results: In crizotinib based regimens, 3 clinical studieswhich including 128 Chinese patients with EML4-ALK positive non-small-cell lung cancer and treated withcrizotinib based regimen were considered eligible for inclusion. Pooled analysis suggested that, in all patients,the pooled RR was 59.3% (76/128) in crizotinib based regimens. ALT/AST mild visual disturbances, nausea, andvomiting were the main side effects. No treatment related death occurred in these crizotinib based treatments.Conclusions: This pooled analysis suggests that crizotinib based regimens are associated with good responserate and accepted toxicities in treating Chinese patients with EML4-ALK positive non-small-cell lung cancer.     

IGF-1R旁路活化在EML4-ALK阳性非小细胞肺癌Alectinib继发耐药中的作用

摘 要：［目的］ 探讨胰岛素样生长因子-1（IGF-1）是否以旁路激活的方式诱导EML4-ALK融合基因阳性肺癌细胞株H3122对Alectinib的耐药,并进一步探讨旁路信号激活在 Alectinib耐药中的作用。［方法］ 通过外源性加入人胰岛素样生长因子1（hIGF-1）刺激H3122细胞株构建Alectinib耐药细胞株H3122-IGF-CR;通过CCK8法检测H3122细胞株及H3122-IGF-CR对不同浓度Alectinib的敏感性,并计算半数抑制浓度IC50和耐药指数;PE Annexin V/7-AAD双染法检测细胞凋亡情况;qRT-PCR检测亲本细胞中IGF-1R的表达情况;蛋白质印记法检测PI3K/AKT, Ras-Raf-MEK-ERK/MAPK信号通路的变化情况。［结果］ qRT-PCR结果显示IGF-1R在H3122细胞中ct值为20.90±0.06,内参ct值为12.48±0.12,ΔCt值＜12, 提示IGF-1R在H3122细胞株中高表达。H3122细胞的活力能被Alectinib抑制,且呈剂量依赖性,其IC50值为0.0173μmol/L;当加入50ng/ml或100ng/ml的hIGF-1刺激后,其对Alectinib敏感性降低,IC50为0.358μmol/L和0.4001μmol/L,耐药倍数为20.6倍和23.0倍。0.03μmol/L Alectinib单药处理48h后H3122细胞的凋亡率为（26.43±0.23）%,而Alectinib联合50、100、150ng/ml hIGF-1刺激48h后,凋亡率分别为（18.95±0.48）%、（15.90±0.16）%、（13.70±0.36）%,显著性低于Alectinib单药组（P<0.05）。外源性hIGF-1与IGF-1R结合后,明显增加细胞中p-IGF-1R及其下游p-AKT、p-mTOR、p-P70S6K、p-ERK的蛋白表达水平（P<0.05）。此外,联合应用IGF-1R抑制剂Linsitinib (OSI-906)可以抑制因hIGF-1配体导致的H3122耐药细胞的活力。［结论］ hIGF-1可通过旁路激活的方式诱导EML4-ALK阳性非小细胞肺癌H3122细胞对Alectinib耐药,其机制可能为激活了其下游信号通路PI3K/AKT,MAPK/ERK,初步证实 IGF-1R信号通路与Alectinib继发耐药相关。     

非小细胞肺癌中EML4-ALK融合及临床治疗进展

肺癌的死亡率居恶性肿瘤的首位。其中,非小细胞肺癌(non-small cell lung cancer,NSCLC)约占80%,被确诊时多为晚期。传统的化疗能改善近期疗效,对生存期的改善有限,故中位生存时间为12个月左右,预后差[1]。     

TKIs治疗EML4-ALK阳性非小细胞肺癌脑转移的研究进展

摘 要：间变性淋巴瘤激酶（anaplastic lymphoma kinase,ALK）基因重排是非小细胞肺癌（NSCLC）一种新的肿瘤驱动基因,促使肺癌发生和进展。近年来针对ALK融合基因的酪氨酸激酶抑制剂崭露头角,相关药物研究在非小细胞肺癌脑转移治疗中有较大进展,成为靶向治疗的热点。全文就治疗ALK阳性NSCLC脑转移的靶向药物的临床研究作一综述。     

EML4-ALK Rearrangement and Its Clinical Significance in Chinese Patients with Advanced Non-Small Cell Lung Cancer

Objective: To identify the clinicopathological characteristics and clinical outcomes of Chinese patients with non-small cell lung cancer (NSCLC) and to investigate possible associations of NSCLC with echinoderm microtubule-associated protein-like 4 (EML4)-anaplastic lymphoma kinase (ALK) and epidermal growth factor receptor (EGFR) mutations. Methods: Patients with stage IV NSCLC were screened for EML4-ALK rearrangement and EGFR mutations at the Peking University Cancer Hospital. EML4-ALK was identified using fluorescent in situ hybridization and confirmed by immunohistochemistry. EGFR mutations were determined using denaturing high-performance liquid chromatography. Results: The incidence of EML4-ALK was 9.7% (11/113). Patients with EML4-ALK were more likely to present the EGFR wild type (WT; p = 0.033). Response to EGFR-tyrosine kinase inhibitor (TKI) was similar between patients with EML4-ALK rearrangement and EGFR mutation (33.3 vs. 46.9%, p = 0.451), but progression-free survival (PFS) was inferior compared to those with EGFR mutation (2.1 vs. 8.8 months, p = 0.032), and similar to patients with WT/nonrearrangement (2.1 vs. 2.2 months, p = 0.696; and general p = 0.023 between the three cohorts). Moreover, 2 patients with concurrent EML4-ALK and EGFR mutations had superior PFS after EGFR-TKI compared to patients with single EML4-ALK rearrangement. Conclusions: Patients with EML4-ALK conferred similar objective response rates after EGFR-TKI although inferior PFS compared to those with EGFR mutation. Coexistence of EML4-ALK and EGFR mutation might represent a separate NSCLC genotype.     

EML4-ALK融合基因在肿瘤中的研究进展

棘皮动物微管结合蛋白4（EML4）-间变淋巴瘤激酶（ALK）融合基因作为近几年新发现的肿瘤相关基因,在多种肿瘤组织中表达。目前针对EML4-ALK融合基因的研究仍以非小细胞肺癌为主,以该融合基因为治疗靶点的ALK抑制剂已经逐渐推向临床。EML4-ALK融合基因与表皮生长因子受体（EGFR）-Kras突变相关性的研究亦为肿瘤的靶向治疗提供了新思路。