Relationship between epidermal growth factor receptor gene mutation and copy number in Chinese patients with non-small cell lung cancer

Epidermal growth factor receptor(EGFR) gene mutation and copy number are useful predictive markers that guide the selection of non-small cell lung cancer(NSCLC) patients for EGFR-targeting therapy.This study aimed to investigate the correlation between EGFR gene mutation and copy number and clinicopathologic characteristics of Chinese patients with NSCLC.NSCLC specimens collected from 205 patients between November 2009 and January 2011 were selected to detect EGFR gene mutations with real-time polymerase chain reaction(RT-PCR) and to detect EGFR gene copy number with fluorescence in situ hybridization(FISH).EGFR mutations primarily occurred in females,non-smokers,and patients with adenocarinomas(all P < 0.001).Tissues from 128(62%) patients were FISH-positive for EGFR,including 37(18%) with gene amplification and 91(44%) with high polysomy.EGFR gene mutation was correlated with FISH-positive status(R = 0.340,P < 0.001).Multivariate analysis showed that not smoking(OR = 5.910,95% CI = 2.363-14.779,P < 0.001) and having adenocarcinoma(OR = 0.122,95% CI = 0.026-0.581,P = 0.008) were favorable factors for EGFR gene mutation.These results show a high frequency of EGFR FISH positivity in NSCLC tissues from Chinese patients and a significant relevance between EGFR gene mutations and FISH-positive status.Among the FISH-positive samples,EGFR gene mutation occurred more frequently in samples with gene amplification compared to those with high polysomy,suggesting that EGFR mutation and gene amplification should be used as clinical decision parameters to predict response to EGFR-targeting therapy.     

Clinicopathologic features and prognostic implications of epidermal growth factor receptor (EGFR) gene copy number and protein expression in non-small cell lung cancer

Increased epidermal growth factor receptor (EGFR) gene copy numbers and mutations predict sensitivity to EGFR tyrosine kinase inhibitor in non-small cell lung cancer (NSCLC). However, the clinicopathologic features of EGFR gene copy status in NSCLC remain unclear. We retrospectively analyzed 262 cases of NSCLC, including 135 squamous cell carcinomas (SCC) and 112 adenocarcinomas (ADC), for which paraffin blocks of the resected primary lung mass were available. None had received EGFR-targeted therapy. EGFR gene copy number was evaluated using fluorescence in situ hybridization (FISH), and EGFR expression was determined immunohistochemically using a tissue microarray. A high EGFR gene copy (EGFR FISH-positive) was found in 30.2% of the cases (amplification in 11.1% and high polysomy in 19.1%). There was no significant difference in EGFR FISH status with respect to SCC and ADC histology. The EGFR FISH-positive rate was higher in non-smokers than in smokers in the multivariate analysis (p=0.012). EGFR expression was significantly associated with a high EGFR gene copy and SCC histology (p=0.000). In the univariate survival analysis, EGFR FISH-positivity predicted worse survival in SCC (p=0.059), especially stage I SCC (p=0.04). EGFR amplification was associated with a shorter survival in node-positive SCC (p=0.015). However, the EGFR gene copy number or protein expression had no influence on the prognosis of ADC. In conclusion, the EGFR FISH-positive rate in Korean patients with NSCLC was similar to rates in Western populations, unlike the higher frequencies of EGFR mutation in East Asians. A high EGFR gene copy number was significantly more common in non-smokers, as were EGFR mutations. A high EGFR gene copy number predicted worse survival in SCC; therefore, the prognostic implications of the EGFR gene and protein should be analyzed in the context of histology and staging in NSCLC.     

Detection of EML4-ALK fusion genes in a few cancer cells from transbronchial cytological specimens utilizing immediate cytology during bronchoscopy

The presence of fusion genes between the anaplastic lymphoma kinase (ALK) and echinoderm microtubule-associated protein-like 4 (EML4) genes is useful for determining appropriate molecular-targeted therapies in patients with non-small cell lung cancer (NSCLC). The diagnosis of NSCLC is often judged from transbronchial cytological specimens. The efficacy of RT-PCR for detection of EML4-ALK fusion genes in transbronchial cytological specimens has not been studied. Here, we evaluated the detection rate of EML4-ALK fusion genes in transbronchial cytological specimens positive for NSCLC by immediate cytology during bronchoscopic examination. Various numbers of H2228 cells carrying EML4-ALK variant 3 were combined with 1×10(6) wild-type WBCs. The RNA was extracted and the sensitivity of detection of the EML4-ALK fusion gene was determined using a nested RT-PCR. A total of 161 cell samples, from cases without available tissue samples, obtained by bronchoscopic examinations utilized for immediate cytology in patients with NSCLC were subsequently analyzed for EML4-ALK fusion genes using a nested multiplex RT-PCR. EML4-ALK variant 3 was detected in a small number of H2228 cells (10 cells), even in the presence of 1×10(6) WBCs (sensitivity: 0.001%). In the patient cytological samples, EML4-ALK fusion genes were detected in five of 161 NSCLCs (3.1%) and four of 88 adenocarcinomas (4.5%). Sequencing confirmed that these samples included three variant 1 genes, one variant 2 gene and one variant 3 gene. Using the same cytological samples, EGFR mutations were detected in 39 of 161 NSCLCs (24.2%) and 36 of 88 adenocarcinomas (40.9%). There was no case in which both EML4-ALK fusion and EGFR mutation were simultaneously detected. Rapid diagnosis during bronchoscopy utilizing immediate cytology contributed to the selection of the best samples for genetic analysis. EML4-ALK fusion genes as well as EGFR mutations were successfully detected in a small number of cancer cells from transbronchial cytological specimens using a nested multiplex RT-PCR. Our present strategy can be integrated into the clinical process without additional invasive examination of patients. In the era of molecular-targeted treatments for NSCLC, the combination of rapid diagnosis during bronchoscopic examination and stocking samples as cDNA could further correspond to genetic analyses of accumulating driver genes in NSCLC.     

Increased epidermal growth factor receptor gene copy number detected by fluorescence in situ hybridization associates with increased sensitivity to gefitinib in patients with bronchioloalveolar carcinoma subtypes: a Southwest Oncology Group Study.

PURPOSE: Bronchioloalveolar carcinoma (BAC) and adenocarcinomas with BAC features seem to be increasing in incidence, particularly in younger, never-smoking women. Epidermal growth factor receptor (EGFR) inhibitors demonstrated response rates of 20% to 30% in patients with advanced BAC subtypes, but selection methods for patient therapy are not established. PATIENTS AND METHODS: EGFR and HER2 gene copy numbers were assessed by fluorescence in situ hybridization (FISH) in 81 patients treated with gefitinib 500 mg/d (Southwest Oncology Group protocol S0126) and were correlated to treatment outcome. Tumors were classified into two main strata: FISH-positive (high polysomy/gene amplification) and FISH-negative (disomy/low polysomy). RESULTS: In 81 patients, the median survival time for EGFR/FISH-negative patients was 8 months and not yet reached for FISH-positive patients (but approaching 18 months; hazard ratio [HR] = 2.02; P = .042). Median progression-free survival time for EGFR/FISH-positive patients was 9 months versus 4 months for the FISH-negative patients (HR = 1.67; P = .072). In multivariate analysis, EGFR copy number by FISH remained a significant predictive factor for survival after accounting for smoking status, sex, histology, and performance status. Fifty-five patients were evaluated for response using Response Evaluation Criteria in Solid Tumors Group, and 12 of 19 EGFR/FISH-positive patients (63%) demonstrated disease control versus 14 (39%) of 36 patients in the FISH-negative group (P = .087). No association was found between HER2 gene copy number and response (n = 39 patients) or survival (n = 56 patients; P > .10). CONCLUSION: Increased EGFR gene copy number detected by FISH is associated with improved survival after gefitinib therapy in patients with advanced BAC, suggesting FISH methodology can be used to assess survival potential in patients treated with EGFR tyrosine kinase inhibitors.     

非小细胞肺癌组织中表皮生长因子受体基因突变与拷贝数之间的相关性以及与患者临床病理特征之间的关系

目的 研究中国非小细胞肺癌(NSCLC)患者组织中表皮生长因子受体(EGFR)基因状态,分析EGFR基因突变与拷贝数之间的相关性以及与NSCLC患者临床病理特征之间的关系。方法 应用实时荧光定量PCR法检测118例NSCLC组织中EGFR基因的突变状态,同时采用荧光原位杂交(FISH)技术检测EGFR基因拷贝数。分析EGFR基因突变与拷贝数之间的相关性,探讨EGFR基因状态与NSCLC患者临床病理特征之间的关系。结果118例NSCLC组织中,EGFR基因的突变率为41.5％,其中腺癌为50.0％,鳞癌为5.0％。EGFR基因FISH阳性率为70.3％,其中29例为基因扩增,54例为高度多体性;腺癌FISH阳性率为78.1％,鳞癌为35.0％。EGFR基因突变与EGFR基因高拷贝数主要存在于腺癌、晚期、女性和不吸烟的患者,EGFR基因突变与EGFR基因拷贝数之间有显著的相关性。结论在中国NSCLC患者中,腺癌、晚期、女性、不吸烟的患者EGFR基因突变率和FISH阳性率较高,且二者具有显著的相关性;联合检测EGFR基因拷贝数和基因突变可能更有利于NSCLC靶向药物的筛选。     

Increased HER2 gene copy number is associated with response to gefitinib therapy in epidermal growth factor receptor-positive non-small-cell lung cancer patients.

PURPOSE: In non-small-cell lung cancer (NSCLC), response to tyrosine kinase inhibitors (TKIs) is significantly associated with the presence of increased copy number and/or activating mutations of the epidermal growth factor receptor gene (EGFR). Preclinical data indicate that HER2, a member of the EGFR family, could enhance TKI sensitivity. PATIENTS AND METHODS: HER2 gene copy numbers per cell were evaluated by fluorescent in situ hybridization (FISH) in 102 NSCLC patients treated with gefitinib, and previously evaluated for EGFR status by FISH, immunohistochemistry, and presence of mutations. RESULTS: Patients with HER2 high copy number (high polysomy and gene amplification [HER2 FISH positive]) represented 22.8% of patients, and compared with patients with no or low gain (HER2 FISH negative), had significantly better objective response (OR, 34.8% v 6.4%; P = .001), disease control rate (DCR, 56.5% v 33.3%; P = .04), time to progression (TTP, 9.05 v 2.7 months; P = .02), and a trend toward longer overall survival (OS, 20.8 v 8.4 months; P = .056). HER2 protein expression investigated by immunohistochemistry was positive in only five of 72 (7%) patients analyzed and all 89 patients tested by DNA sequencing were negative for mutations in HER2 exon 20. Patients with HER2 FISH-positive tumors displaying increased expression of EGFR protein, gene gain, or mutations (EGFR positive) had a significantly better OR, DCR, TTP, and OS than patients negative for both receptors. CONCLUSION: Increased copy number of the HER2 gene is associated with gefitinib sensitivity in EGFR-positive patients, supporting use of HER2 FISH analysis for selection of patients for TKI therapy.     

非小细胞肺癌表皮生长因子受体基因拷贝数与核苷酸切除修复交叉互补基因1和乳腺癌易感基因1的表达及其相关性分析

目的 探讨表皮生长因子受体(EGFR)基因拷贝数与铂类耐药相关基因核苷酸切除修复交叉互补基因1(ERCC1)和乳腺癌易感基因1(BRCA1)在非小细胞肺癌(NSCLC)中的表达情况,以及三者之间的相关性.方法 用荧光原位杂交(FISH)技术检测EGFR基因的扩增情况,应用免疫组化SP法检测132例NSCLC患者标本ERCC1和BRCA1蛋白的表达,并进一步分析EGFR基因拷贝数、ERCC1和BRCA1的蛋白表达与患者临床病理特征的关系.结果 EGFR基因FISH阳性率为24.1% (40/166).女性的扩增阳性率高于男性(31.9%和18.6%,P=0.048);无吸烟史的患者扩增阳性率明显高于有吸烟史的患者(32.8%和16.7%,P=0.045);基因拷贝数增加与患者的年龄、临床分期、病理类型及有无淋巴结或远处转移均无关.ERCC1蛋白表达阳性率为45.5% (60/132),在不同的病理类型分布比较,差异有统计学意义(P=0.046),与患者的性别、年龄、临床分期、有无淋巴结或远处转移及吸烟状况均无关.BRCA1蛋白表达阳性率为35.1%(46/131),与患者的性别、年龄、临床分期、病理类型、淋巴结或远处转移及吸烟状况无关.ERCC1与BRCA1的蛋白表达呈中等相关(r=0.449,P＜0.001),与EGFR扩增无相关性(P=0.785);BRCA1表达与EGFR基因拷贝数状态无相关性(P=0.143).结论 在肺癌的个体化治疗中,检测EGFR基因拷贝数、ERCC1和BRCA1的表达对靶向治疗和铂类药物化疗的选择具有重要的临床指导意义.

Abstract：

Objective To evaluate the expression of epidermal growth factor receptor (EGFR) gene copy number and the expression of ERCC1 and BRCA1 proteins in patients with non-small-cell lung cancer (NSCLC) and the correlation between them. Methods The status of EGFR gene copy number was determined by in situ hybridization (FISH), and the expression of ERCC1 and BRCC1 proteins was examined by immunohistochemistry (IHC). The relationship of EGFR gene copy number with the expression of ERCC1 and BRCA1 and the clinical pathologic features were analyzed. Results FISH-positive EGFR expression was identified in 40 of 166 samples (24.1%). More FISH-positive EGFR in the female than male patients (31.9% vs. 18.6%, P=0.048), and non-smoker than smoker (32.8% vs. 16.7%, P=0.045). FISH-positive EGFR was not associated with age, pathological type, clinical stage and metestasis status (P＞0.05). The expression of ERCC1 protein was identified in 60 of 132 samples (45.5%). The expression of ERCC1 protein varied significantly in tumors of different pathological types (P=0.046), but not associated with age, gender, clinical stage, metestatic status and smoking status (P＞0.05). The expression of BRCA1 protein was identified in 46 of 131 samples (35.1%). The expression of BRCA1 was not associated with age gender, pathological type, clinical stage, metestatic ststus and smoking status (P＞0.05). There was a moderate correlation between the expressions of ERCC1 and BRCA1 (r=0.449, P＜0.001), but EGFR gene copy number was not correlated with the expression of ERCC1 or BRCA1 protein. Conclusions FISH-positive EGFR expression is associated with gender and smoking status, but not correlated with the expression of ERCC1 and BRCA1 proteins. There is a moderate correlation between the expressions of ERCC1 and BRCA1.     

Comparative analysis of epidermal growth factor receptor mutations and gene amplification as predictors of gefitinib efficacy in Japanese patients with nonsmall cell lung cancer

BACKGROUND: Because the investigation of epidermal growth factor receptor gene (EGFR) status as a predictor of gefitinib efficacy in Japanese patients has shown promise, the authors evaluated EGFR mutations and gene amplification in biopsy specimens from Japanese patients with nonsmall cell lung cancer (NSCLC) who received treatment with gefitinib to analyze the correlation between EGFR gene status and clinical outcome. METHODS: Fifty-nine patients were enrolled in this study. EGFR gene amplification was evaluated by fluorescence in situ hybridization (FISH), and EGFR mutations in exons 18, 19, and 21 were analyzed by polymerase chain reaction and direct sequencing. RESULTS: EGFR mutations were detected in 17 patients (28.8%). FISH-positive results were observed in 26 patients (48.1%). The response rate was significantly higher in the patients with EGFR mutations than in the patients without mutations (58.8% vs 14.3%; P=.0005). No significant difference in the response rate was observed between FISH-positive patients and FISH-negative patients (31.8% vs 21.4%; P=.4339). EGFR mutation was correlated with both a longer time to progression (TTP) (7.3 months vs 1.8 months; P=.0030) and longer overall survival (OS) (18.9 months vs 6.4 months; P=.0092). No significant differences in TTP or OS were observed between FISH-positive patients andFISH-negative patients. The results from a multivariate analysis indicated that EGFR mutations maintained a significant association with longer TTP and longer OS. CONCLUSIONS: The results of this study suggested that EGFR mutations may serve as predictors of response and survival and that the role of EGFR gene amplification is not a predictor of gefitinib efficacy in Japanese patients with NSCLC.     

非小细胞肺癌组织MET和EGFR基因扩增与预后相关性分析

目的：探讨非小细胞肺癌（non-smfllleelllungcancer,NSCLC）患者中肝细胞生长因子受体（MET）基因和表皮生长因子受体（epidermalgrowthfactorreceptor,EGFR）基因扩增与临床病理特征及预后的关系。方法：回顾分析唐山市协和医院（48例）和唐山市人民医院（109例）2001—01—2007—01手术切除的NSCLC石蜡包埋标本157例。应用荧光原位杂交（fluorescenceinsituhybridization,FISH）检测NSCLCMET、EGFR基因扩增情况,并结合临床病理资料进行统计分析。应用SPSS16．0进行统计分析,Kaplan-Meier模型分析中住生存期（overallsurvival,0S）,Log—rank检验比较生存曲线,多因素分析采用Cox回归模型。结果：157例NSCLC患者标本中,EGFR基因扩增70例（44．6％）。EGFR基因扩增与年龄、性别、吸烟状态、组织类型和TNM分期无关,P〉0．05。157例NSCLC患者标本中,MET基因扩增25例（15．9％）。EGFR扩增患者MET扩增率为22．9％,高于无EGFR扩增患者MET扩增率10．3％,P=0．033。MET基因扩增与年龄、性别、吸烟状态、组织类型和TNM分期无关,P〉0．05。Kaplan-Meier生存分析显示,I＋Ⅱ期中位生存期为51个月,明显高于Ⅲ＋Ⅳ期中位生存期29个月,P=0．001。EGFRFISH阳性患者中位0s为33个月与EGFRFISH阴性患者中位0s39个月比较,差异无统计学意义,P=0．495。METFISH阳性患者中位0S为29个月,低于METFISH阴性患者37个月,P=0．044。患者0s与病理类型、年龄、性别和吸烟状态无相关性,P〉0．05。多因素分析显示,临床分期、MET基因扩增与OS有关（相对危险度为12．573、6．892,P值分别为0．015、0．018）。结论：临床Ⅲ＋Ⅳ期和MET基因扩增NSCLC患者预后不良,EGFR基因扩增与NSCLC患者预后无关。     

Combination of EGFR gene copy number and protein expression predicts outcome for advanced non-small-cell lung cancer patients treated with gefitinib.

BACKGROUND: Biological markers for optimal selection of patient to epidermal growth factor receptor (EGFR)-targeted therapies are not established in advanced non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: EGFR/HER2 gene copy number by FISH, EGFR protein and pAKT expression by immunohistochemistry (IHC) and EGFR and KRAS mutations were tested in 204 gefitinib-treated NSCLC patients. RESULTS: Increased EGFR and HER2 gene copy number (FISH+), EGFR protein overexpression (IHC+), EGFR mutations and pAKT overexpression were all associated with significantly higher response rates (33%, 29%, 22%, 39% and 20% respectively). EGFR FISH+ (32%) and IHC+ (61%) correlated with improved survival, while EGFR mutations (27%), KRAS mutations (26%) and pAKT expression (69%) did not. In multivariate survival analysis EGFR FISH and IHC were independent predictive markers. EGFR FISH+/IHC+ patients (23%) had a median survival of 21 months versus 6 months for double-negative patients (30%). CONCLUSION: Combination of EGFR FISH and IHC is effective predictor for benefit from gefitinib. Patients with double-negative results are unlikely to benefit in western NSCLC populations.     

Immunohistochemical screening for anaplastic lymphoma kinase (ALK) rearrangement in advanced non-small cell lung cancer patients

Fluorescence in situ hybridization (FISH) is currently used to detect non-small cell lung cancer (NSCLC) patients with anaplastic lymphoma kinase (ALK) gene rearrangement, who are candidates for ALK inhibitor therapy. However, FISH may not be a practical method for screening for ALK-positive patients in a large population due to its cost and difficulty in interpretation. We investigated the role of immunohistochemistry (IHC) to screen for ALK rearrangement in advanced NSCLC. We identified 1,166 stage IIIB or IV NSCLC patients with non-squamous histology from the Seoul National University Hospital NSCLC database. To enrich ALK-positive cases, we selected 262 patients who were either EGFR wild-type or non-responders to previous EGFR tyrosine kinase inhibitors (TKI). ALK IHC and ALK FISH were performed on formalin-fixed, paraffin-embedded tissue. ALK protein was expressed in 28 (10.7%) tumors in 262 patients. ALK FISH was positive in 25 (9.5%) cases. All patients with IHC score of 3 (n=9) were FISH-positive and all patients with score of 0 (n=234) were FISH-negative. Among patients with IHC scores of 1 and 2, five (83.3%, 5/6) and eleven (84.6%, 11/13) were FISH-positive, respectively. The sensitivity and specificity of ALK IHC with intensity score of 1 or more were 100% and 98.7%, respectively. IHC can be a useful test for screening ALK FISH-positive cases in advanced NSCLC. FISH testing should be considered for advanced NSCLC patients with tumors showing mild to moderate staining for ALK by IHC to confirm ALK translocation.     

Gefitinib (ZD1839): therapy in selected patients with non-small cell lung cancer (NSCLC)?

PURPOSE: To evaluate response rate, toxicity and epidermal growth factor (EGFR) mutations and gene copy number as outcome predictive factors in Italian patients with non-small cell lung cancer (NSCLC) treated with gefitinib (Iressa) in an expanded access program (EAP). PATIENTS AND METHODS: A total of 137 patients with advanced NSCLC received gefitinib as first line treatment or after failure of chemotherapy. In 43 cases, tissue specimens were available for EGFR status evaluation: immunohistochemical (IHC) for EGFR, fluorescence in situ hybridisation (FISH) or Chromogenic in situ hybridisation (CISH)-(ISH) analysis for EGFR and HER2 gene copy number, and PCR-DNA sequencing for mutational analysis of EGFR were performed. RESULTS: In the study population, response rate (PR) was 13%; disease stabilization (DS) 26%; overall disease control rate 39%; median survival 6.3 months and time to progression 2.7 months. Toxicity was mild (G3 skin toxicity in 3% and G3 liver toxicity in 4% of patients). An EGFR-mutation was detected in 9/43 patients: Eight deletions in exon 19 and 1 missense mutation in exon 21. Increased gene copy number for EGFR and/or HER2 was detected in 17/43 patients. Response rate was significantly higher in women, non-smokers, in mutation carriers than in wild type carriers, in EGFR-trisomy/polysomy carriers and HER2-trisomy/polysomy carriers. CONCLUSIONS: In this study, response rate and toxicity to gefitinib treatment were consistent with previously reported data for whites. Female gender, absence of smoking history, EGFR-mutations, EGFR and HER2-polysomy were significantly associated with response to gefitinib therapy in NSCLC patients.     

KRAS mutation is an important predictor of resistance to therapy with epidermal growth factor receptor tyrosine kinase inhibitors in non-small-cell lung cancer.

PURPOSE: EGFR gene mutations and increased EGFR copy number have been associated with favorable response to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (EGFR-TKI) in patients with non-small-cell lung cancer (NSCLC). In contrast, KRAS mutation has been shown to predict poor response to such therapy. We tested the utility of combinations of these three markers in predicting response and survival in patients with NSCLC treated with EGFR-TKIs. EXPERIMENTAL DESIGN: Patients with advanced NSCLC treated with EGFR-TKI with available archival tissue specimens were included. EGFR and KRAS mutations were analyzed using PCR-based sequencing. EGFR copy number was analyzed using fluorescence in situ hybridization. RESULTS: The study included 73 patients, 59 of whom had all three potential markers successfully analyzed. EGFR mutation was detected in 7 of 71 patients (9.8%), increased EGFR copy number in 32 of 59 (54.2%), and KRAS mutation in 16 of 70 (22.8%). EGFR mutation (P<0.0001) but not increased EGFR copy number (P=0.48) correlated with favorable response. No survival benefit was detected in patients with either of these features. KRAS mutation correlated with progressive disease (P=0.04) and shorter median time to progression (P=0.0025) but not with survival. Patients with both EGFR mutation and increased EGFR copy number had a >99.7% chance of objective response, whereas patients with KRAS mutation with or without increased EGFR copy number had a >96.5% chance of disease progression. CONCLUSION: KRAS mutation should be included as indicator of resistance in the panel of markers used to predict response to EGFR-TKIs in NSCLC.     

Biomarkers for prediction of sensitivity to EGFR inhibitors in non-small cell lung cancer

PURPOSE OF REVIEW: Epidermal growth factor receptor (EGFR) Inhibitors have shown promising results in patients with advanced non-small cell lung cancers (NSCLC) who previously have failed on chemotherapy. Objective response is achieved in 10 to 28% of the patients, and about 30% will achieve stable disease. A major problem is how to select the patients, who will benefit from treatment, and who will not. RECENT FINDINGS: The predictive role of EGFR protein expression assessed by IHC is still debated. Specific EGFR gene mutations have been identified associated with response to gefitinib (Iressa(R)), but seem not to be associated with stable disease. No studies have yet demonstrated any association between EGFR gene mutations and survival. In this review we describe other marker studies, which are associated with sensitivity to EGFR inhibitors. Increased EGFR gene copy number based on FISH analysis is demonstrated to be a good predictive marker for response, stable disease, time to progression, and survival. SUMMARY: EGFR/FISH seems today to be the best predictive marker for clinical benefit from EGFR inhibitors in NSCLC. Prospective large scale clinical studies must identify the most optimal paradigm for selection of patients.     

miRNAs与非小细胞肺癌EGFR突变及放疗相关性研究进展

EGFR作为NSCLC靶向治疗的热点,近年来其在分子生物学水平的研究众多。而放疗作为一种NSCLC重要的传统治疗方法,其疗效与EGFR突变及过表达相关。放疗联合EGFR-TKI在NSCLC治疗上的疗效还缺乏Ⅲ期临床结果。miRNAs能够调控肿瘤相关基因表达,影响肿瘤生物学活动。近来研究显示miRNAs对EGFR突变、EGFR-TKI和放疗均存在正向或负向的调控作用,其具体机制已部分阐明。现就miRNAs对EGFR突变、EGFR-TKI及放疗间相关性作一综述,旨在为miRNAs应用于放疗联合EGFR-TKI治疗NSCLC提供最新诊疗依据。     

Association of epidermal growth factor receptor (EGFR) gene mutations with EGFR amplification in advanced non-small cell lung cancer

Somatic mutations in the epidermal growth factor receptor (EGFR) gene are associated with the response to EGFR tyrosine kinase inhibitors in patients with non-small cell lung cancer (NSCLC). Increased EGFR copy number has also been associated with sensitivity to these drugs. However, given that it is often difficult to obtain sufficient amounts of tumor tissue for genetic analysis from patients with advanced NSCLC, the relationship between these two types of EGFR alterations has remained unclear. We have now evaluated EGFR mutation status both by direct sequencing and with a high-sensitivity assay, the Scorpion-amplification-refractory mutation system, and have determined EGFR copy number by fluorescence in situ hybridization (FISH) analysis in paired tumor specimens obtained from 100 consecutive patients with advanced NSCLC treated with chemotherapy. EGFR mutations or FISH positivity (EGFR amplification or high polysomy) were apparent in 18% (18/100) and 32% (32/100) of patients, respectively. The Scorpion-amplification-refractory mutation system was more sensitive than direct sequencing for the detection of EGFR mutations. Furthermore, EGFR mutations were associated with EGFR amplification (P = 0.009) but not with FISH positivity (P = 0.266). Our results therefore suggest the existence of a significant association between EGFR mutation and EGFR amplification in patients with advanced NSCLC.     

Afatinib and lung cancer

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKI) have an established role in the treatment of non-small-cell lung cancer (NSCLC). First-generation reversible ATP-competitive EGFR-TKIs are approved for the initial treatment of patients with EGFR mutation-positive advanced NSCLC. Afatinib is an irreversible second-generation EGFR-TKI with potent preclinical activity against EGFR (wild type and mutant), HER2, HER4 and EGFR-mutant NSCLC with acquired resistance to reversible EGFR-TKI. LUX-Lung 3 trial demonstrated superiority of afatinib to cisplatin and pemetrexed in the frontline treatment of treatment-naïve patients with advanced adenocarcinoma of the lung and EGFR mutation. Based on these results, afatinib was recently approved for the first-line treatment of NSCLC patients with EGFR mutation. This article summarizes current status of preclinical and clinical development of afatinib in NSCLC.     

Application of non-small cell lung cancer pleural effusion cell blocks in molecular pathological detection

Objective:The tumor tissues used in molecular pathological detection were usual y obtained by surgery, which would cause trauma and may not be suitable for the terminal cancer patients. This paper evaluated the value of the non-smal celllung cancer (NSCLC) pleural ef usion cellblocks as tumor tissues replacement materials in the application of molecular pathological detection. Methods: Tumor cells were made into cellblocks through stratified centrifugal from 30 NSCLC pa-tients with the pleural ef usion. The immunohistochemistry, fluorescence in situ hybridization (FISH) and gene sequencing methods were employed in our experiments. Results:The tumor cells of cellblock section were rich and could keep part of histological structure. Immunohistochemistry staining could assist diagnosis and tumor parting. Epidermal growth factor receptor (EGFR) FISH-positive was found in 33.33%of the group, high polysomy in 6 cases, amplification in 4 cases. EGFR gene mutations were found in 8 cases of 30 samples, with an incidence of 26.67%, 6 cases were detected in the exon 19, and 2 cases were detected in the exon 21. Conclusion:The NSCLC pleural ef usion cellblocks are useful for the diagnosis and determining the primary source of tumor, instructed targeted therapy.     

Epidermal growth factor receptor in non-small-cell lung carcinomas: correlation between gene copy number and protein expression and impact on prognosis.

PURPOSE: The epidermal growth factor receptor (EGFR) is frequently overexpressed in non-small-cell lung carcinoma (NSCLC), and EGFR inhibitors are promising new therapeutic agents. The molecular mechanisms responsible for EGFR overexpression are poorly understood. Materials and METHODS: Gene copy number and protein status of EGFR were investigated in microarrayed tumors from 183 NSCLC patients, including squamous cell carcinoma (SCC; 89 patients) and non-SCC (94 patients) histologies. Protein expression was assessed by immunohistochemistry on a scale from 0 to 400 (percentage of positive cells x staining intensity). Gene and chromosome 7 copy numbers were identified by fluorescent in situ hybridization (FISH). RESULTS: EGFR protein overexpression was observed in 62% of the NSCLC (25% scored 201 to 300; 37% scored 301 to 400), more frequently in SCC than non-SCC (82% v 44%; P <.001), and in 80% of the bronchioloalveolar carcinomas. The prevalent FISH patterns were balanced disomy (40%) and trisomy (38%) for EGFR gene and chromosome 7 (40%), whereas balanced polysomy was seen in 13% and gene amplification was seen in 9% of the patients. Gene copy number correlated with protein expression (r = 0.4; P <.001). EGFR overexpression or high gene copy numbers had no significant influence on prognosis. CONCLUSION: EGFR overexpression is frequent in NSCLC, is most prominent in SCC, and correlates with increased gene copy number per cell. High gene copy numbers per cell showed a trend toward poor prognosis. It will be important to evaluate EGFR gene and EGFR protein status and signal protein expression to properly interpret future clinical trials using EGFR inhibitors.