非小细胞肺癌中EGFR和K-ras基因突变检测

目的:探讨不同类型非小细胞肺癌的EGFR和K-ras基因突变情况及其与肺癌相关临床病理特征的关系。方法:用厦门艾德ADxARMS试剂盒进行98例非小细胞肺癌患者肿瘤组织中EGFR（18,19,20,21外显子）基因和K-ras（12,13,61密码子）基因突变的检测。所有患者均未接受过吉非替尼的治疗。结果:98例样本中31例发生了EGFR基因突变,突变率为31.6%（31/98）,其中15例为19外显子缺失,13例为21 L858R外显子点突变,3例为20外显子突变,1例为18外显子突变。其中1例既有19外显子缺失突变,又有20外显子突变。腺癌中EGFR基因突变率较鳞癌、腺鳞癌、大细胞癌高。女性患者EGFR基因突变率较男性高。不吸烟患者EGFR基因突变率较吸烟患者高。低分化腺癌患者EGFR基因突变率较中、高分化患者高。21例发生了K-ras基因突变（21.4%）,其中12、13、61密码子均发现突变。突变率腺癌较鳞癌、腺鳞癌、大细胞癌高,与是否吸烟、患者性别、分化程度均无相关性。结论:非小细胞肺癌患者EGFR基因突变检出率较高,K-ras基因突变率较低,且两者不存在同时突变,EGFR基因突变与肺癌组织学类型、分化程度、性别等相关。K-ras基因突变与组织学类型相关。     

非小细胞肺癌患者EGFR基因突变与吉非替尼临床疗效关联

目的:评估吉非替尼（Gefitinib）疗效和晚期难治性非小细胞肺癌（NSCLC）患者表皮生长因子受体（EGFR）突变情况的关联。方法:121名晚期难治性非小细胞肺癌患者,均是经过一线化疗方案失败的中晚期非小细胞肺癌患者,每日予以口服吉非替尼250mg治疗,直到疾病进展或出现不可耐受的毒副反应为止。在开始治疗之前检测EGFR18、19、21位点,于治疗期间进行常规检查和规范的随访。分析疗效、突变以及中位生存期之间的关联。结果:在115名有效随访的患者中,13例完全缓解,25例部分缓解,38例稳定,39例病情进展。疾病控制率66.3%。1年和2年生存率分别为59.7%和26.9%。中位生存期16个月。115人中有38例病人存在EGFR突变。EGFR突变的病人表现出对吉非替尼较敏感。不吸烟的女性患者有较好的疗效和较长的生存期。而患者年龄、一线化疗周期、肿瘤分期的组间差异对于生存期的影响都无显著差异。结论:吉非替尼在女性不吸烟非小细胞肺癌患者中疗效是确定的。西部女性肺腺癌患者拥有较高的突变率和较长的生存时间。     

非小细胞肺癌EGFR基因突变及与疗效的相关性研究

目的:研究晚期非小细胞肺癌(NSCLC)患者表皮生长因子受体(EGFR)基因突变情况,探讨其与NSCLC临床病理学特征及吉非替尼疗效的关系。方法:PCR扩增和基因测序的检测60例NSCLC患者EGFR基因第18、19、20和21外显子突变情况。靶向治疗组14例吉非替尼治疗;化疗组46例以GP方案(顺铂联合吉西他滨方案)治疗。结果:60例晚期NSCLC中,EGFR基因突变率30.00%,19外显子突变12例,21外显子突变6例。腺癌、无吸烟史和女性患者EGFR基因突变率分别为36.89%、50.00%和57.14%。14例EGFR突变阳性患者口服吉非替尼组,CR 1例,PR 10例,SD 2例和PD 1例,客观有效率为78.57%,疾病控制率为92.85%;4例EGFR突变阳性患者GP方案化疗组,CR 0例,PR 2例,SD 2例和PD 0例,客观有效率为50.00%。42例EGFR突变阴性GP方案化疗组,客观有效率为38.10%。结论:晚期NSCLC患者EGFR基因突变率较高,EGFR基因的突变与肿瘤的病理类型、性别、年龄、民族、吸烟指数相关。EGFR基因突变KTI治疗,可有效提高患者的疾病缓解率,并较好地预测TKI治疗晚期非小细胞肺癌的疗效。     

Impact of EGFR mutation analysis in non-small cell lung cancer

The discovery of mutations in the tyrosine kinase domain of the epidermal growth factor receptor (EGFR) gene in non-small cell lung cancer (NSCLC) accelerated the research of molecular-targeted therapy by EGFR-tyrosine kinase inhibitors (TKIs), such as gefitinib and erlotinib. About 90% of EGFR mutations are clustered in exons 19 (deletion) and 21 (point mutation at codon 858) and patients with these mutations have great response to EGFR-TKIs. However, tumors that initially respond to EGFR-TKIs almost inevitably become resistant later and T790M secondary mutation in the EGFR gene and MET amplification are reported to account for the mechanism of this acquired resistance. In this review, we summarize the recent findings about EGFR mutations, amplification, alterations of other related genes and sensitivity and acquired resistance to EGFR-TKIs. We also discuss from our studies the relationship between EGFR mutations and other molecular alterations such as aberrant methylation in tumor suppressor genes (TSGs), which indicates that they are related to the mechanism of the pathogenesis of lung cancer. The accumulated important data confer further insights on translational research, providing us with the new strategies for the treatment of NSCLCs.     

老年晚期非小细胞肺癌患者ＥＧＦＲ基因的突变研究

目的　探讨老年晚期非小细胞肺癌（ＮＳＣＬＣ）患者ＥＧＦＲ基因突变情况及其与临床病理特征之间的关系。方法　采用ＰＣＲ扩增和实时荧光ＰＣＲ技术分析ＮＳＣＬＣ中ＥＧＦＲ基因第１９和２１号外显子的突变情况。结果　８６例老年ＮＳＣＬＣ酪氨酸激酶域存在体细胞突变２５例（２９.１％）,其中第１９号外显子的缺失突变为１３例（１５.１％）,第２１号外显子的替代突变为１２例（１４.０％）。肺腺癌、肺泡癌的突变率为３６.４％（２４／６６）,高于鳞癌的６.３％（１／１６）;女性患者突变率为４８.３％（１４／２９）,高于男性患者的１９.３％（１１／５７）;非吸烟患者的突变率为４３.９％（１８／４１）,高于长期吸烟者的１５.６％（７／４５）。结论 中国老年ＮＳＣＬＣ患者ＥＧＦＲ基因酪氨酸激酶区第１９和２１外显子的突变特征与肺癌总体患者类似,与年龄关系不大,突变率以腺癌、女性及非吸烟者较高。老年ＮＳＣＬＣ患者同样可以通过基因检测获得ＴＫＩ治疗预测信息。     

非小细胞肺癌患者细胞学标本EGFR基因突变检测及其临床病理意义

目的: 探讨细胞学标本在非小细胞肺癌(NSCLC)的诊断及个体化治疗中的临床应用价值。方法: 收集352例新鲜细胞学标本制片后,行常规HE染色;同时选择TTF-1、NapsinA、CK7、CEA、CD56、Syn、P63、CK5/6、WT-1、E-cadherin等抗体对来源不明的肿瘤细胞进行免疫细胞化学标记,并对明确诊断为NSCLC的病例,采用突变扩增阻滞系统(ARMS)检测表皮生长因子受体(EGFR)基因突变情况。结果: 352例患者中,345例有癌细胞。经临床及免疫细胞化学证实345例恶性细胞中,NSCLC有335例,且NSCLC细胞学标本中有302例DNA提取成功,占90.15%(302/335)。EGFR 基因检测结果显示,EGFR 共突变123例,总突变率为40.73%(123/302)。其中,第18、19、20、21外显子的突变率分别为0.99%(3/302)、19.21%(58/302)、0.66%(2/302)和19.87% (60/302); EGFR 18、19、21外显子突变占EGFR 突变总数的98.37%(121/123)显著高于EGFR 20外显子突变(P<0.05)。302例患者中,女性患者EGFR 突变率为54.35% (75/138),明显高于男性患者29.27%(48/164)(P<0.05);非吸烟患者EGFR 的突变率为51.49% (104/202),显著高于吸烟者19%(19/100)(P<0.05)。276例腺癌中EGFR 突变率44.20%(122/276);非腺癌EGFR 突变率4.34%(1/23);腺癌EGFR 突变率明显高于其他类型(P<0.05)。结论: 利用新鲜细胞学标本,结合免疫细胞化学标记和ARMS分子病理技术有助于晚期非小细胞肺癌的诊断,并为表皮生长因子受体酪氨酸激酶抑制剂(EGFR-TKIs)个体化治疗提供可靠依据。     

非小细胞肺癌ROS1突变与EGFR突变及临床病理特征的关系

目的 探讨非小细胞肺癌（NSCLC）中ROS1融合突变与表皮生长因子受体（EGFR）突变及临床病理特征的关系。方法 采用实时荧光定量PCR（QPCR）检测2014年12月至2017年12月收治的3487例中国西北地区NSCLC患者ROS1基因的突变情况，同时采用ARMS法检测ROS1基因突变患者的EGFR基因突变情况，分析ROS1和EGFR共突变患者的临床病理特征。结果 3487例NSCLC患者中，ROS1基因突变54例（1.5％）。ROS1基因突变与年龄、性别、吸烟史、病理类型和临床分期有关（P＜0.05）。54例ROS1融合基因突变患者中有3例（5.6％）同时存在EGFR基因突变，其中19外显子缺失突变（19-del）2例，L858R突变1例。3例ROS1突变均为突变体2型（R2）。结论 中国西北地区NSCLC患者ROS1融合基因突变率为1.5％，与EGFR基因突变可以共存。     

非小细胞肺癌E GF R基因突变的表现及其与肿瘤标记物的相关性

目的：探讨非小细胞肺癌（NSCLC）EGFR基因突变位点状态,分析其与血清肿瘤标记物NSE、CEA、CYFRA21－1、TSGF间的关系。方法：回顾性分析240例NSCLC患者组织标本中EGFR不同位点基因突变状态,分析基因突变率与患者性别、年龄、吸烟史和组织分型间的关系及NSCLC患者19、21突变位点与肿瘤标记物NSE、CEA、CYFRA21－1、TSGF的相关性。结果：240例标本突变135例,18号外显子突变2例（1．5％）;19号外显子突变47例（34．8％）;20号外显子突变7例（5．2％）;21号外显子突变71例（52．6％）;双突变8例（5．9％）。EGFR突变主要发生在19、21号外显子上,其中19号外显子突变与组织分型有关（P＜0．05）,与年龄、性别、吸烟史无关（P＞0．05）;21号外显子突变与组织分型、吸烟史、性别有关（P＜0．05）,与年龄无关（P＞0．05）。EGFR突变组肿瘤标志物NSE、CEA、CYFRA21－1、TSGF的表达水平与未突变组之间差异无统计学意义（P＞0．05）,19、21号外显子突变的肿瘤标记物NSE、CEA、CYFRA21－1、TSGF之间的差异也无统计学意义（P＞0．05）。结论：NSCLC的EGFR突变中19、21号外显子突变率显著高于其他类型,这对于指导临床合理应用EGFR－TKIs药物治疗有重要的意义。而肿瘤标记物NSE、CEA、CYFRA21－1、TSGF在突变组与未突变组之间、19和21号外显子突变之间的差异均无统计学意义。因此,血清肿瘤标记物可能不足以作为评估EGFR突变的指标。     

中国非小细胞肺癌患者表皮生长因子受体基因突变的研究

目的:针对表皮生长因子受体(EGFR)的分子靶向治疗越来越受到国内外的广泛关注,其中EGFR酪氨酸激酶抑制剂(TKI)Gefitinib和Erlotinib已在中国上市,批准用于治疗晚期非小细胞肺癌(NSCLC).EGFR突变是靶向药物TKI治疗有效的一个预测指标.有关我国非小细胞肺癌患者EGFR基因突变的研究已有若干报道,本文意在探讨中国北方地区非小细胞肺癌患者表皮生长因子受体(EGFR)基因外显子18-21的突变特点.方法:收集50例来自北方地区的非小细胞肺癌患者的冰冻组织标本,进行EGFR基因外显子18-21的突变检测.结果:50例非小细胞肺癌组织中共检出突变15例(30%),其中外显子19突变6例,均为缺失突变del E746-A750,外显子21突变9 例 ,除1例为L861Q外, 其它均为 L858R替代突变 .女性患者的突变率( 12/23,52%)显著高于男性患者的突变率( 3/27 , 11%),P＝0.002 ;腺癌支气管肺泡癌患者的突变率( 13/26,50%)显著高于鳞癌患者的突变率( 2/20,10%),P=0.005;非吸烟者的突变率(10 /25,40%)高于吸烟者的突变率(5/25,20%),但无显著性差异,P=0.217.与其它报道比较,结果显示北方地区EGFR基因突变的总体发生率与其他地区无显著性差异 ,外显子19、20、21发生突变所占的比例除云南更常见于外显子19,有显著性差异(P＜0.05)外,与其他地区无显著性差异(P＞0.05).但北方地区突变的形式相对单一 .结论:中国南北方地区非小细胞肺癌患者EGFR基因突变发生率及主要突变类型基本一致,北方地区突变类型较单一,可给予针对性的检测.     

非小细胞肺癌患者恶性胸腔积液中EGFR基因突变

非小细胞肺癌患者接受表皮生长因子受体-酪氨酸激酶抑制剂(EGFR-TKI)治疗前进行EGFR检测已经成为共识.恶性胸腔积液是非小细胞肺癌(NSCLC)患者常见的临床表现,采用不同方法对胸腔积液细胞及游离核酸提取后进行EGFR检测,对预测EGFR-TKI的疗效有着良好前景.     

EML4-ALK与EGFR基因突变共存型非小细胞肺癌研究进展

肺癌是最常见的恶性肿瘤之一,其中非小细胞肺癌(non-small celllung cancer,NSCLC)占肺癌的80%-85%。分子靶向治疗是目前NSCLC最热门也是最具前景的领域之一,其中的热点分子包括表皮生长因子受体(epidermal growth factor receptor,EGFR)、棘皮动物微管样蛋白4-间变淋巴瘤激酶(echinoderm microtubuleassoci atedprotein like4-anaplastic lymphoma kinase,EML4-ALK)等。既往研究认为EML4-ALK融合基因与EGFR突变不能共存。近期陆续报道了EML4-ALK融合基因与EGFR突变共存的病例。本文就EML4-ALK融合基因及EGFR突变基因的分子结构、发生率和目前已报道双突变患者的临床特点等进行综述。     

国产吉非替尼与原研药一线治疗EGFR阳性晚期NSCLC对比研究

目的一代表皮生长因子受体酪氨酸激酶抑制剂(epidermal growth factor receptor tyrosine kinase inhibitors,EGFR-TKIs)吉非替尼是表皮生长因子受体EGFR敏感基因突变晚期非小细胞肺癌(non-small cell lung cancer,NSCLC)的一线治疗药物。本研究对比分析国产吉非替尼与原研药一线治疗EGFR敏感突变[19外显子Del和21(L858R)点突变]的临床疗效及安全性,探讨国产吉非替尼与原研药疗效的一致性。方法选取2017-03-01-2019-01-31淮北市人民医院收治的经病理学确诊的晚期EGFR突变的NSCLC患者70例,采用随机数字表法随机分为国产吉非替尼组35例和原研药组35例,4周为1个周期,每2个周期评价疗效。观察2组的有效率(response rate,RR)、疾病控制率(disease control rate,DCR)、无进展生存期(progression-free survival,PFS)、毒副作用及预后等。采用SPSS 19.0对数据进行统计分析。结果国产吉非替尼组RR为65.7%,原研药组为71.4%,χ~2=0.265,P=0.607。DCR国产吉非替尼组为82.9%,原研药组为91.4%,χ~2=1.148,P=0.284。中位PFS国产吉非替尼组为9.1个月,原研药组为9.5个月,χ~2=0.021,P=0.884。RR国产吉非替尼组19外显子Del的为78.3%,原研药组为83.3%,χ~2=0.005,P=0.943。DCR国产吉非替尼组19外显子Del的为91.3%,原研药组为95.8%,χ~2=0.001,P=0.970。RR国产吉非替尼组21(L858R)点突变的为41.7%,原研药组为45.5%,χ~2=0.034,P=0.885;DCR国产吉非替尼组21(L858R)点突变的为66.7%,原研药组为81.8%,差异无统计学意义,χ~2=0.683,P=0.408。2组患者中19外显子Del的RR为80.9%,21(L858R)点突变的为43.5%,χ~2=10.009,P=0.002;19外显子Del的DCR为93.6%,21(L858R)点突变的为73.9%,χ~2=5.351,P=0.021。2组患者中19外显子Del的中位PFS为11.7个月,21(L858R)点突变的为8.6个月,差异有统计学意义,χ~2=10.798,P=0.001。2组主要的毒副作用是腹泻和皮疹,多为Ⅰ~Ⅱ度,差异无统计学意义,P>0.05。结论国产吉非替尼与原研药治疗EGFR敏感突变的晚期NSCLC疗效及不良反应相当,19外显子Del的患者较21(L858R)点突变的患者疗效更佳。     

Gefitinib therapy for non-small cell lung cancer

Opinion statement Gefitinib is a small molecule that specifically inhibits the tyrosine kinase activity of the epidermal growth factor receptor (EGFR) type 1 by interfering with the adenosine triphosphate (ATP) binding site. At doses that maximally inhibit EGFR tyrosine kinase activity chosen for phase II trials, the most common side effects of gefitinib are low-grade rash or diarrhea. An infrequent but serious side effect of gefitinib is interstitial lung disease (ILD). The Iressa dose evaluation for advanced lung cancer phase II trials (IDEAL 1 and IDEAL 2) of single agent gefitinib, 250 or 500 mg orally per day in pretreated patients with non-small cell lung cancer (NSCLC), found about 20% of patients on IDEAL-1 and 10% of patients on IDEAL-2 had major objective responses and improvement of symptoms. The data from the IDEAL trials and the extensive experience from the 21,000 patients treated on the expanded access program, suggests that the patients who have a major objective response probably have a significant survival benefit in addition to palliative benefit. In addition, approximately 40% of patients on the IDEAL trials experienced improvement in symptoms. Gefitinib was approved for third line treatment of NSCLC. Gefitinib is effective, safe, and well-tolerated single-agent therapy in previously treated NSCLC. Although there have been no direct comparisons, the small molecule inhibitors of EGFR gefitinib and erlotinib appear to have similar efficacy. Erlotinib has been shown to produce a survival advantage compared to best supportive care in an unselected group of previously treated patients with NSCLC. Until similar trials are completed comparing gefitinib to best supportive care, there is a similar survival advantage for gefitinib. Nonsmokers, women, and patients with adenocarcinoma, are more likely to have major objective responses than other patients. Bronchioalveolar lung cancer is a subtype of NSCLC that is more likely to respond to gefitinib. Several groups have now reported that most, but not all, tumors experiencing a major objective response to gefitinib have mutations associated with the ATP-binding site of EGFR. It is reasonable to move gefitinib in to second-line therapy for patients who are known to have a tumor that is more likely to respond to gefitinib. Also, I would treat such patients with gefitinib as first-line therapy on an appropriate clinical trial approved by the Institutional Review Board (IRB). Outside of a clinical trial, patients with advanced disease should initially be treated with a combination of doublet chemotherapy. There is strong evidence that there is no benefit to concurrent chemotherapy and gefitinib. Gefitinib should not be given concurrently with cytotoxic chemotherapy as initial treatment for NSCLC. Sequential therapy combining chemotherapy and gefitinib in advanced disease or as adjuvant therapy should only be done in the context of a clinical trial approved by the IRB. There is preclinical evidence suggesting that gefitinib is a radiosensitizer. Early results from trials combining radiation, or chemoradiotherapy with gefitinib have shown that these combinations are without excessive additive toxicity. There is no proven clinical benefit for concurrent Gefitinib and radiation. Gefitinib should only be given with radiation as part of an appropriate clinical trial approved by the IRB.     

非小细胞肺癌组织中 EGFR 基因突变与 ERCC1 mRNA 表达的关系

目的：探讨非小细胞肺癌中EGFR基因突变与ERCC1 mRNA 表达之间的关系。 方法：收集NSCLC患者病例样本41例,应用ARMS方法检测EGFR基因突变,采用RT-PCR方法检测ERCC1 mRNA 表达,应用Spearman相关检验对EGFR突变状态与ERCC1 mRNA 的表达进行相关性分析。 结果：在41例患者中,EGFR突变21例,ERCC1 mRNA 高、中、低表达率分别为19.1%(4/21)、57.1%(12/21)和23.8%(5/21),EGFR基因突变与ERCC1 mRNA 表达显著相关(P < 0.001)。 结论: NSCLC EGFR基因突变与ERCC1 mRNA 表达具有显著相关性。     

Schedule-dependent antitumor activity of the combination with erlotinib and docetaxel in human non-small cell lung cancer cells with EGFR mutation, KRAS mutation or both wild-type EGFR and KRAS

Erlotinib is used as a standard treatment for recurrent advanced non-small cell lung cancer (NSCLC). Epidermal growth factor receptor (EGFR) mutations in NSCLC have been shown to be a predictive factor of erlotinib, although the relationship between K-ras oncogene (KRAS) mutations and erlotinib resistance is controversial. Recently, in vitro sequence-dependent interactions of erlotinib and docetaxel have been studied on as a novel therapeutic approach against NSCLC. The purpose of the present study was to determine the optimum novel regimen of erlotinib and docetaxel against NSCLC cells which have EGFR mutation (HCC827 cells), KRAS mutation (A549 cells) or both wild-type (NCI-H292 cells). First, we analyzed the effects of in vitro combination for cell proliferation-inhibition using a combination index. In all cell lines, docetaxel followed by erlotinib treatment showed nearly additive effects. On the other hand, erlotinib followed by docetaxel treatment showed remarkable antagonistic interactions. Second, we examined the effect of combinations on the in vitro apoptosis induction. Erlotinib followed by docetaxel treatment reduced apoptosis induction compared with docetaxel alone; in contrast, docetaxel followed by erlotinib treatment had no inhibitory effects on docetaxel-induced apoptosis in any of the cell lines. Finally, an in vivo tumor growth inhibition test was performed using xenograft models. Docetaxel followed by erlotinib administration resulted in significant tumor growth inhibition compared with erlotinib or docetaxel monotherapy in all models. In conclusion, we demonstrated that docetaxel followed by erlotinib therapy was a potentially optimum regimen against NSCLC regardless of the mutation status of EGFR and KRAS.     

Sequential occurrence of non-small cell and small cell lung cancer with the same EGFR mutation

We report a case of small cell lung cancer (SCLC) developing after prolonged treatment (more than 2 years) for primary adenocarcinoma of the lung, and we show that both the SCLC and non-small cell lung cancer (NSCLC) tissues obtained from the same site share the same deletion in exon 19 of EGFR. This case suggests that the activating EGFR mutations may confer the pathogenesis of a subset of SCLC.     

突变特异性免疫组织化学法检测非小细胞肺癌EGFR基因突变

背景与目的：表皮生长因子受体(epidermal growth factor receptor,EGFR)基因的突变状态是非小细胞肺癌(non-small cell lung cancer,NSCLC)患者使用EGFR酪氨酸激酶抑制剂(tyrosine kinase inhibitors, TKIs)的重要疗效预测指标。该研究旨在探讨突变特异性免疫组织化学(immunohistochemistry,IHC)法检测NSCLC标本EGFR基因突变的临床实用价值。方法：同时采用突变特异性IHC法和扩增阻滞突变系统(amplifi-cation refractory mutation system,ARMS)法检测290例NSCLC患者的EGFR基因突变状态,计算突变特异性IHC法检测EGFR基因突变的灵敏度、特异度、阳性预测值(positive predictive value,PPV)和阴性预测值(negative predictive value,NPV);比较ARMS法和突变特异性IHC法检测EGFR突变的一致性。结果：以ARMS法检测结果为金标准,当染色评分≥1+为阳性时,突变特异性IHC法诊断EGFR基因突变的灵敏度为72.92%,特异度为95.20%,PPV为93.75%,NPV为78.08%。突变特异性IHC法诊断不同类型EGFR基因突变的准确性相差明显：诊断19外显子缺失突变的灵敏度只有55.55%,但其特异度在99%以上;当染色评分为1+时,诊断L858R突变的灵敏度为90.27%,特异度为95.86%,当染色评分为2+或3+时,其特异度则为98.63%~100%。突变特异性IHC法与ARMS法检测结果有较好的一致性(P<0.001,Kappa值：0.612~0.864)。突变特异性IHC法能直观判断EGFR基因突变细胞丰度。结论：突变特异性IHC法是EGFR突变分子检测的有效补充。     

Afatinib increases sensitivity to radiation in non-small cell lung cancer cells with acquired EGFR T790M mutation

Afatinib is a second-generation of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor and has shown a significant clinical benefit in non-small cell lung cancer (NSCLC) patients with EGFR-activating mutations. However, the potential therapeutic effects of afatinib combining with other modalities, including ionizing radiation (IR), are not well understood. In this study, we developed a gefitinib-resistant cell subline (PC-9-GR) with a secondary EGFR mutation (T790M) from NSCLC PC-9 cells after chronic exposures to increasing doses of gefitinib. The presence of afatinib significantly increases the cell killing effect of radiation in PC-9-GR cells harboring acquired T790M, but not in H1975 cells with de novo T790M or in H460 cells that express wild-type EGFR. In PC-9-GR cells, afatinib remarkable blocks baseline of EGFR and ERK phosphorylations, and causes delay of IR-induced AKT phosphorylation. Afatinib treatment also leads to increased apoptosis and suppressed DNA damage repair in irradiated PC-9-GR cells, and enhanced tumor growth inhibition when combined with IR in PC-9-GR xenografts. Our findings suggest a potential therapeutic impact of afatinib as a radiation sensitizer in lung cancer cells harboring acquired T790M mutation, providing a rationale for a clinical trial with combination of afatinib and radiation in NSCLCs with EGFR T790M mutation.