Combined targeting of endothelin A receptor and epidermal growth factor receptor in ovarian cancer shows enhanced antitumor activity

Ovarian carcinomas overexpress endothelin A receptors (ET(A)R) and epidermal growth factor (EGF) receptor (EGFR). In these cells, endothelin-1 (ET-1) triggers mitogenic and invasive signaling pathways that are in part mediated by EGFR transactivation. Combined targeting of ET(A)R, by the specific ET(A)R antagonist ZD4054, and of EGFR by the EGFR inhibitor gefitinib (IRESSA), may offer improvements in ovarian carcinoma treatment. In HEY and OVCA 433 ovarian carcinoma cells, ET-1 or EGF induced rapid activation of EGFR, p42/44 mitogen-activated protein kinase (MAPK), and AKT. ZD4054 was able to reduce the ET-1-induced EGFR transactivation. Gefitinib significantly inhibited EGF- and ET-1-induced EGFR phosphorylation, but incompletely reduced the ET-1-induced activation of downstream targets. ZD4054 plus gefitinib resulted in a greater inhibition of EGFR, MAPK, and AKT phosphorylation, indicating the critical role of these interconnected signaling proteins. ZD4054 effectively inhibited cell proliferation, invasiveness, and vascular endothelial growth factor (VEGF) secretion. Concomitantly, ZD4054 enhanced apoptosis and E-cadherin promoter activity and expression. In both cell lines, the drug combination resulted in a significant decrease in cell proliferation (65%), invasion (52%), and VEGF production (50%), accompanied by a 2-fold increase in apoptosis. The coadministration of ZD4054 enhanced the efficacy of gefitinib leading to partial (82%) or complete tumor regression on HEY ovarian carcinoma xenografts. Antitumor effects were paralleled by biochemical and immunohistologic evidence of decreased vascularization, Ki-67, matrix metalloproteinase-2 (MMP-2), VEGF, MAPK and EGFR, and enhanced E-cadherin expression. The cross-signaling between the EGFR/ET(A)R pathways provides a rationale to combine EGFR inhibitors with ET(A)R antagonists, identifying new effective therapeutic opportunities for ovarian cancer.     

Targeting the epidermal growth factor receptor in non-small cell lung cancer

The epidermal growth factor receptor (EGFR) has been implicated in a multiplicity of cancer-related signal transduction pathways like cellular proliferation, adhesion, migration, neoangiogenesis and apoptosis inhibition, all of them important features of cancerogenesis and tumour progression. The inhibition of this receptor has been discovered as a suitable pharmaceutical intervention aimed at interrupting tumour activity. In cancer, both monoclonal antibodies and small molecules with anti-tyrosine kinase activity have been assessed in several trials with significant efficacy in clinical applications. The current review focuses in particular on the clinical data of EGFR inhibition in non-small cell lung cancer with emphasis on tyrosine kinase inhibition.     

miR-134靶向EGFR对非小细胞肺癌增殖的影响

目的 探讨微小RNA-134（miR-134）对非小细胞肺癌（NSCLC）细胞增殖和凋亡的影响及可能的机制。方法 采用实时荧光定量PCR（QPCR）检测miR 134在NSCLC细胞株（A549、H252）和正常胚肺细胞株WI38中的表达情况;将A549和H252细胞分为3组,分别为空白对照组（不转染）、miR-NC组（转染不相关siRNA）和miR-134组（转染miR-134 mimics）。分别于转染后24、48、72、96h收集细胞,采用MTS法检测细胞的增殖情况;转染后96h用流式细胞仪检测细胞的凋亡情况;双荧光素酶报告基因实验检测miR-134与表皮生长因子受体（EGFR）3’UTR的结合情况,QPCR检测过表达miR-134的A549和H252细胞中EGFR的表达情况。结果 与WI38 细胞相比,miR-134在A549细胞中的表达下调85.91％,在H252细胞中下调78.13％（P＜0.05）。MTS检测显示,miR-134能显著降低A549和H252细胞的增殖能力,并呈时间依赖性。流式细胞仪检测显示,与空白对照组比较,miR-134组A549细胞的凋亡比例提高226.31％,H252细胞提高47.85％（P＜0.05）。双荧光素酶报告基因实验显示miR 134能与EGFR3’UTR结合,显著降低荧光值（P＜0.05）。QPCR检测显示,与空白对照组比较,转染miR-134 mimics 后,EGFR在A549细胞中的相对表达量下调57.0％,在H252中下调35.0％,差异均有统计学意义（P＜0.01）。结论 miR-134在NSCLC中低表达,能通过靶向EGFR抑制NSCLC细胞增殖,并诱导凋亡。     

Erlotinib-induced autophagy in epidermal growth factor receptor mutated non-small cell lung cancer

Purpose

Erlotinib is a commonly used tyrosine kinase inhibitor (TKI) in non-small cell lung cancer (NSCLC). Autophagy is a catabolic process in response to stress and deprivation of nutrients. This study aims to investigate whether autophagy confers acquired resistance to erlotinib treatment in NSCLC.

Methods

Four NSCLC cell lines (HCC827, HCC4006, H358 and H1975) with different epidermal growth factor receptor (EGFR) mutation status (exon 19 deletion, exon 19 deletion, wild-type and L858R/T790M respectively) were selected. MTT assay, crystal violet staining and Annexin-V assay were performed to determine cell viability and apoptosis. Autophagic proteins were detected by Western blot. Acidic vesicular organelle (AVO) formation was determined by acridine orange staining. Autophagy inhibitor (chloroquine) and RNA interference were used to demonstrate the biological effect of erlotinib-induced autophagy.

Results

In line with EGFR mutation status, it was shown that both HCC827 and HCC4006 cells were sensitive to erlotinib, while H358 and H1975 cell lines were resistant. Erlotinib treatment at clinically relevant concentrations induced autophagy (increased LC3II expression, Atg-5/Atg12 conjugation, formation of AVO and p62 degradation) in sensitive NSCLC cell lines, via p53 nuclear translocation, AMPK activation and mTOR suppression. Addition of chloroquine, as an autophagy inhibitor, enhanced erlotinib sensitivity in sensitive cells. Similarly, silencing of Atg5 or Beclin-1 significantly increased sensitivity to erlotinib in both sensitive cell lines. In contrast, there was no induction of autophagy in resistant H358 and H1975 cell lines upon erlotinib exposure.

Conclusions

Erlotinib can induce both apoptosis and autophagy in sensitive NSCLC cell lines with activating EGFR mutation (exon 19 del). Inhibition of autophagy can further enhance sensitivity to erlotinib in EGFR-mutated NSCLC, suggesting that autophagy may serve as a protective mechanism.     

Characterization of epidermal growth factor receptor in primary human non-small cell lung cancer

Membrane preparations from 36 human non-small cell lung cancers were examined for the expression of epidermal growth factor (EGF) receptors, and comparisons were made between tumor types and stage. Eight normal lung membrane preparations were also examined. The concentrations of EGF receptors were assessed by ligand binding studies using 125I-radiolabeled EGF. In two point saturation experiments using 0.3 nM 125I-EGF incubated with membranes from 35 primary lung tumors, a median of 18 fmol/mg of protein (range, 1.1 to 530) was found. This was significantly greater than binding to eight lung membranes: median, 6.1 fmol/mg of protein (range, 1.0 to 14.5) (P less than 0.02). Scatchard binding curves obtained in 21 of the 36 tumors and seven of eight of the normal lung preparations showed high and low affinity sites for EGF receptors on all but two tumor membranes. The dissociation constant of the high affinity sites was similar on tumor and normal lung membranes: range, 0.75 to 30 x 10(-10) M/liter. However, the tumors had a significantly higher concentration of these receptor sites: median, 30.4 fmol/mg of protein versus a median of 6.2 fmol/mg of protein on normal lung membranes (P less than 0.01). Likewise, there were significantly more low affinity sites on tumors: median, 237 fmol/mg compared to 60.2 fmol/mg on normal lung (P less than 0.01). No differences were found in this analysis between tumors of different histological subtypes or clinical stage. It is possible that the high level of expression of high affinity sites on lung tumors could be used as a target for ligand-complexed drugs.     

表皮生长因子受体与非小细胞肺癌预后之间的关系

目的探讨细胞膜及细胞核内表皮生长因子受体(EGFR)水平与非小细胞肺癌(NSCLC)预后之间的关系。方法选取2010年4月至2013年4月间南京市溧水区人民医院保存的60例非小细胞肺癌患者的病理档案,采用免疫组化的方法分析其病理组织切片中细胞膜及细胞核内EGFR及细胞周期蛋白D1(Cyclin D1)的表达。结果 39例(65.0%)样本细胞膜EGFR呈阳性,7例(11.7%)样本细胞膜EGFR呈强阳性;18例(30.0%)样本细胞核EGFR呈阳性和5例(8.3%)样本细胞核EGFR呈强阳性。Kaplan-Meier生存分析和Log-rank检验发现非小细胞肺癌患者细胞膜EGFR强阳性与总体生存率(OS)无明显相关,差异无统计学意义(P>0.05),细胞核EGFR强阳性组与总体生存率(OS)呈负相关,差异有统计学意义(P<0.01)。细胞核EGFR表达水平与Cyclin D1之间正相关,差异有统计学意义(P<0.05),细胞膜EGFR表达水平与Cyclin D1之间无明显相关,差异无统计学意义(P>0.05)。结论细胞核内EGFR水平与非小细胞肺癌患者的预后相关,核内EGFR强阳性者预后差。     

Update on epidermal growth factor receptor mutations in non-small cell lung cancer.

In 2004, several investigators reported that somatic mutations in the epidermal growth factor receptor gene were associated with clinical responses to erlotinib and gefitinib in patients with non-small cell lung cancer. Since then, multiple groups have examined the biological properties that such mutations confer as well as the clinical relevance of these mutations in patients with non-small cell lung cancer. Although a tremendous amount of knowledge has been gained in the past 2 years, there remain a number of important epidemiologic, biological, and clinical questions.     

EGFR在非小细胞肺癌中的表达及临床意义

目的：探讨表皮生长因子受体（EGFR）在非小细胞肺癌（NSCLC）中的表达及其与NSCLC发生、发展及预后的关系,指导非小细胞肺癌的靶向治疗。方法：回顾性分析82例NSCLC手术病例临床病理资料及随访资料,用免疫组化（EnVision法）的方法观察EGFR在非小细胞肺癌组织中的表达,对比分析20例非恶性肺组织中EGFR的表达。结果：EGFR在NSCLC中的表达率为53.66%,在非恶性肺组织中EGFR均呈阴性表达;EGFR在NSCLC中的表达与患者的性别、病理类型、TNM分期及淋巴结转移有显著统计学意义（P〈0.05）;EGFR高表达者生存期短。结论：EGFR在NSCLC中高表达;女性患者高于男性,并且与患者的病理类型、TNM分期及淋巴结转移有密切的关系,可作为判断NSCLC患者病情进展及预后的重要指标,还可以指导NSCLC患者的靶向治疗。     

Second-generation epidermal growth factor receptor tyrosine kinase inhibitors in non-small cell lung cancer

Inhibiting epidermal growth factor receptor (EGFR) signaling has proven to be an effective strategy for treating non-small cell lung cancer (NSCLC) patients and the first generation of agents developed for this purpose, gefitinib and erlotinib, stimulated a unique escalation in both biologic and clinical research within the field. Second-generation EGFR-targeted agents that aim to further improve patient outcomes are now in preclinical and clinical trials. This review discusses four promising agents that are currently being studied in NSCLC: EKB-569, HKI-272, CI-1033, and ZD6474.     

靶向NSCLC EGFR exon20插入突变的新抗原疫苗筛选和功能研究

目的:筛选具有免疫源性HLA-A^*02限制性表皮生长因子受体(epidermal growth factor receptor,EGFR)exon20插入突变编码的优势表位肽,为携带EGFR exon20插入突变的非小细胞肺癌(non-small cell lung cancer,NSCLC)提供新的免疫治疗手段。方法:通过IEDB、NetMHC 4.0和SYFPEITHI软件,筛选EGFR exon20插入突变编码的HLA-A^*02限制性表位,针对细胞毒性T淋巴细胞表位集中区域设计多肽疫苗,通过体外实验验证其免疫活性。结果:V769_D770insASV为EGFR exon20插入突变最高频突变位点(19.35%),经软件预测其编码的多肽YVMASVASV与HLA-A^*02具有较强的结合力。围绕核心序列设计两条优势表位多肽E-ASV-10和E-ASV-19,体外可诱导HLA-A^*02限制性T细胞的扩增和活化,上调4-1BB⁺CD25⁺...     

EGFR在女性非小细胞肺癌中的表达及临床意义

背景与目的：近年来女性肺癌发病率的明显增加引起人们的关注.本研究主要是以女性非小细胞肺癌为研究对象,探讨表皮生长因子受体（epidermal growth fator receptor,EGFR）在女性非小细胞肺癌（non-small cell lung cancer,NSCLC）中的表达及其与女性NSCLC发生、发展及预后的关系,指导女性非小细胞肺癌的靶向治疗.方法：回顾性分析62例女性非小细胞肺癌手术病例临床病理资料及随访资料,用免疫组化的方法检测EGFR在女性非小细胞肺癌组织中的表达,对比分析10例非恶性肺组织中EGFR的表达,用Cox模型进行生存分析.结果：EGFR在62例女性NSCLC中的表达率70.97%,在非恶性肺组织中均呈阴性表达,两者比较差异有显著性（P＜0.05）;EGFR在女性腺癌的表达高于鳞癌（P＜0.05）,尤其在细支气管肺泡癌中的表达更高（P＜0.05）;EGFR表达与女性NSCLC的TNM分期及淋巴结转移呈显著正相关（P＜0.05）;EGFR高表达的女性患者生存期短、预后差（P＜0.05）;Cox比例风险模型分析表明,患者术后生存时间与病理类型、淋巴结是否转移显著相关（P＜0.05）,腺癌、有淋巴结转移是患者独立的不良预后因素.结论：女性NSCLC中EGFR的表达与患者病理类型、TNM分期及淋巴结转移有密切的关系,EGFR在女性NSCLC中高表达,可作为判断女性NSCLC病情进展及预后的重要指标,还对NSCLC女性患者的靶向治疗的选择有一定的指导意义.     

Mutations of the epidermal growth factor receptor in non-small cell lung cancer -- search and destroy

The targeting of the ATP binding pocket of the epidermal growth factor receptor (EGFR) tyrosine kinase, by the small molecule drugs gefitinib and erlotinib, represents a promising new therapeutic strategy in non-small cell lung cancer. However, it is now apparent that only a subset of patients responds to such treatment. Two publications in early 2004 reported the presence of activating mutations in the EGFR tyrosine kinase gene conferring exquisite sensitivity to these drugs. Several publications have since reported prospective data consistent with this finding. This brief review summarises the mutation data from 15 such studies in terms of mutation frequency by clinicopathological features and correlation with response to tyrosine kinase inhibition. A new paradigm for the routine detection of such mutations is needed to facilitate patient selection for treatment and further studies.     

Soluble epidermal growth factor receptor isoforms in non-small cell lung cancer tissue and in blood

Epidermal growth factor receptor (EGFR) is implicated in tumor development and is highly expressed in many human tumors. EGFR overexpression has been observed in both premalignant lesions and in malignant lung tumors, as well as in 40-80% of patients with non-small cell lung cancer (NSCLC). EGFR is a 170-kDa transmembrane glycoprotein with an extracellular ligand-binding domain and a cytoplasmic domain with intrinsic tyrosine kinase activity. Soluble forms of EGFR (sEGFR) containing the extracellular domain have been described both in conditioned media from EGFR overexpressing cells as well as in peripheral blood. However, very little is known regarding the molecular function and the biochemical properties of these circulating EGFR isoforms. This study investigates the expression of sEGFR in lung cancer cultured cells and NSCLC patients with the aim of identifying clinically relevant isoforms specifically produced by tumor cells. Proteomic approaches including OFFGEL electrophoresis and Western blotting analysis were used to assess the sEGFR expression pattern in primary lung tumor samples, normal counterparts and matched plasma. We discover that the isoelectric points of sEGFR isoforms in NSCLC biopsy tissue differ from those of the isoforms present in healthy tissue and detected in the plasma of all subjects. These results demonstrate, for the first time, the existence of sEGFR isoforms specifically produced by NSCLC tumor cells which could represent a new potential biomarker for diagnosis and therapy of lung tumors. However, our observations indicate that more highly sensitive and specific quantitative assays are needed in order to reliably detect the tumor-associated sEGFR isoforms in plasma samples.     

Tumor epidermal growth factor receptor genotype and depression in stage IV non-small cell lung cancer

Introduction.

Depression appears to be associated with worse survival from cancer, but underlying mechanisms for this association are unknown. In the present study, we explored the degree to which tumor genotype may be associated with depression in patients with non-small cell lung cancer (NSCLC). We examined differences in depression severity and rates of positive screens for major depressive disorder among newly diagnosed patients with stage IV NSCLC and known epidermal growth factor receptor (EGFR) genotype.

Methods.

Newly diagnosed patients (n = 53) with metastatic NSCLC attending an initial thoracic oncology consultation completed self-report questionnaires regarding demographics, smoking behavior, and depression before meeting with their oncologist. Biopsy samples were subsequently genotyped, including screening for EGFR mutations. We conducted a retrospective chart review to obtain clinical data, including tumor stage, performance status, and EGFR genotype.

Results.

Twelve patients (22.6%) tested positive for EGFR mutation. No EGFR mutation–positive cases met the screening criteria for major depressive disorder, in comparison with 29.3% of patients with wild-type EGFR (p = .03). Mutations of EGFR were also associated with lower depression severity than with wild-type EGFR, independent of gender, performance status, and smoking history (p < .05). This finding persisted for both the cognitive–affective and somatic domains of depression symptoms.

Conclusions.

EGFR mutations were associated with lower depression severity and lower rates of probable major depressive disorder in patients with metastatic NSCLC, based on mood screening performed before results of genotyping were known. Findings support further work to explore the directionality of the associations and potential biological pathways to depression.     

表皮生长因子受体和血管内皮生长因子在非小细胞肺癌中的表达及意义

目的　观察非小细胞肺癌（ＮＳＣＬＣ）组织中表皮生长因子受体（ＥＧＦＲ）和血管内皮生长因子（ＶＥＧＦ）的表达情况以及与临床病理参数的关系。方法　免疫组织化学法检测７６例ＮＳＣＬＣ组织和１４例非恶性肺组织ＥＧＦＲ和ＶＥＧＦ的表达。结果　ＥＧＦＲ和ＶＥＧＦ在７６例ＮＳＣＬＣ组织中的阳性表达率分别为４７.４％（３６／７６）和５１.３％（３９／７６）,在１４例非恶性肺组织表达率分别为７１４％（１／１４）和７.１４％（１／１４）,两组ＥＧＦＲ、ＶＥＧＦ表达差异显著（Ｐ＜０.０５）。Ⅲ期ＮＳＣＬＣ组织的ＥＧＦＲ表达率为５６.８％（２５／１９）,高于Ⅰ ～Ⅱ期患者的３１.３％（１０／３２）,两者差异显著（Ｐ＜０.０５）,ＥＧＦＲ表达与其他临床病理参数均无关;淋巴结阳性的ＮＳＣＬＣ组织ＶＥＧＦ表达率为７７.８％（２８／３４）,明显高于淋巴结阴性的２７.５％（１１／４２）,两者差异显著（Ｐ＝０.０００）,ＶＥＧＦ表达与肿瘤分期、性别、年龄、肿瘤细胞分化等临床病理参数亦无关。ＥＧＦＲ和ＶＥＧＦ在ＮＳＣＬＣ组织中表达无相关性（Ｐ＞０.０５）。结论　ＮＳＣＬＣ组织中ＥＧＦＲ和ＶＥＧＦ常常为高表达,ＥＧＦＲ表达与肿瘤的ＴＮＭ分期有关,ＶＥＧＦ与淋巴结转移有关;但是ＥＧＦＲ和ＶＥＧＦ的表达之间无相关性。     

非小细胞肺癌组织化疗前后表皮生长因子受体基因的突变

目的:探讨非小细胞肺癌(non-small cell lung cancer,NSCLC)患者化疗前、后肿瘤组织中表皮生长因子受体(epidermal growth factor receptor,EGFR)基因外显子19和21的突变状况。方法:提取31例NSCLC患者化疗前、后肿瘤组织标本中的基因组DNA,采用巢式PCR技术扩增EGFR基因外显子19和21,并进行测序分析。结果:6例患者化疗前、后EGFR基因发生突变,其中4例为19号外显子发生缺失突变,2例为2l号外显子发生替代突变,且化疗前、后的突变状况一致。女性患者突变率(2/3)高于男性(4/28)(P=0.029),非吸烟者的突变率(4/9)高于吸烟者(2/22)(P=0.043)。结论:NSCLC组织EGFR基因外显子19和21突变在化疗前、后无明显改变。     

Interleukin-8 stimulates cell proliferation in non-small cell lung cancer through epidermal growth factor receptor transactivation

Interleukin-8 (IL-8; CXCL8) is a cytokine of the CXC chemokine family that is involved in neutrophil recruitment and activation. In addition, IL-8 has been implicated in a wide variety of other processes, including angiogenesis and metastasis in lung cancer. Lung adenocarcinoma and muco-epidermoid carcinoma cells produce substantial amounts of IL-8, and express both CXCR1 and CXCR2 IL-8 receptors. We hypothesized that IL-8 stimulates proliferation of non-small cell lung cancer cells, involving transactivation of the epidermal growth factor receptor (EGFR). The EGFR plays a central role in regulating cell proliferation and it has been therefore implicated in lung cancer. Both EGFR ligands and transactivation of the receptor may lead to downstream signalling events, including mitogen-activated protein kinase (MAPK) activation. Transactivation of the EGFR has been shown to occur in response to ligands of various G-protein coupled receptors (GPCRs) and involves metalloproteinase-mediated release of membrane bound EGFR ligands. The aim of the present study was to investigate the effect of IL-8 on proliferation of lung adenocarcinoma and muco-epidermoid carcinoma cells, and to explore the mechanisms leading to this proliferation in two different non-small cell lung cancer cell lines (A549 and NCI-H292). In both NSCLC cell lines, we observed that IL-8 stimulates epithelial cell proliferation in a dose-dependent manner. The ability of IL-8 to increase cell proliferation was blocked both by an inhibitor of EGFR tyrosine kinase, by a specific anti-EGFR blocking antibody and by a panmetalloproteinase inhibitor. Similar results were obtained using the GPCR inhibitor pertussis toxin. Inhibition of the MAPK p42/44 (ERK1/2) also blocked the mitogenic effect of IL-8, while a p38 MAPK inhibitor did not affect IL-8-induced cell proliferation. These results suggest that IL-8 increases cell proliferation in NSCLC cell lines via transactivation of the EGFR and that this mechanism involves metalloproteinase activity.     

Predictive and prognostic markers for epidermal growth factor receptor inhibitor therapy in non-small cell lung cancer

Epidermal growth factor receptor (EGFR) related therapies - mainly tyrosine kinase inhibitors (TKIs) such as erlotinib and gefitinib, but also monoclonal antibodies targeting EGFR, for example, cetuximab - have been investigated in numerous settings in non-small cell lung cancer (NSCLC) and in different combinations. The overall clinical benefit of EGFR TKI therapy is roughly 10-30%, with higher benefit in nonsmoker Asiatic women with EGFR-mutated adenocarcinoma. Currently, there are several biomarkers that are able to direct and predict the yield of EGFR-related therapies in NSCLC. These include EGFR mutation status, EGFR protein expression, EGFR gene copy number and a serum proteomic marker (Veristrat?, Biodesix; CO). The usage of such biomarkers is important from many aspects. First, it helps clinicians to make the right treatment decisions and second, it leads to a wiser usage of financial resources. This review will focus on EGFR-related biomarkers for their prognostic power and their ability to predict clinical benefit from EGFR-related therapy.