HGF/c-MET信号通路抑制剂在抗胰腺癌中的研究进展

胰腺癌是恶性程度较高的肿瘤之一.靶向治疗日渐成为胰腺癌治疗的重要组成部分.研究证实肝细胞生长因子及其受体(HGF/c-MET)信号通路在胰腺癌发生、发展过程中起重要作用,通过抑制该条信号通路能够起到显著的抗胰腺癌作用.因此,HGF/c-MET靶向抑制剂的研究为胰腺癌的治疗开辟了一条新的途径.     

HGF/c-Met信号传导通路与晚期非小细胞肺癌关系的研究进展

 肝细胞生长因子（hepatocyte growth factor,HGF）/c-Met信号传导通路在晚期非小细胞肺癌（non-small cell lung cancer,NSCLC）的发生、发展中起重要调控作用,并与表皮生长因子受体酪氨酸激酶抑制剂的继发性耐药密切相关。针对该通路的分子靶向治疗为晚期NSCLC提供了新的思路,现已成为近年研究的热点。本文就HGF/c-Met的结构、功能及其在晚期NSCLC中的治疗进展等作一综述。     

c-MET通路和抑制剂在非小细胞肺癌中的研究进展

c-MET被认为是继表皮生长因子受体(epidermal growth factor receptor,EGFR)基因突变和间变性淋巴瘤激酶(anaplastic lymphoma kinase,ALK)基因融合之后,非小细胞肺癌(non-small cell lung cancer,NSCLC)又一个重要的驱动基因.MET的激活包括突变、扩增和蛋白质过表达,是NSCLC潜在的治疗靶点,并提示与预后相关.临床证据表明,MET既可以作为肺癌的原发致癌驱动基因,也是EGFR靶向治疗获得性耐药的原因之一.本文主要对c-MET通路在NSCLC中的活性形式及治疗的研究进展进行综述.     

非小细胞肺癌的分子靶向治疗进展

目前在全球范围内肺癌已成为发病率和死亡率增长最快、严重危害人类健康和生命的恶性肿瘤之一.在我国肺癌病死率已居肿瘤死亡率首位,其中非小细胞肺癌(NSCLC)约占肺癌的80%以上,且多数患者确诊时已属晚期,因此内科治疗仍是肺癌的主要治疗方法.但近十年来以化疗为主的治疗手段并未使非小细胞肺癌的疗效获得突破性进展.20世纪90年代以来,关于肺癌的分子靶向治疗研究不断深入,其中以表皮生长因子受体和肿瘤血管生成作为靶点的药物为主,部分药物已经在晚期NSCLC治疗中显示出较好的临床疗效.21世纪分子靶向治疗已取得了飞跃的进展,许多新的靶向性治疗研究为NSCLC治疗提供新的治疗途径.本研究将从以表皮生长因子受体为靶点药物,抗肿瘤血管生成药物以及多靶点抗肿瘤药物3个方面就目前非小细胞肺癌靶向治疗的研究进展作一介绍.     

肝细胞生长因子及其受体c—met在非小细胞肺癌中的表达及其与淋巴管生成的关系’

目的检测肝细胞生长因子（HGF）及其受体c-met在非小细胞肺癌（NSCLC）中的表达,探讨其与NSCLC淋巴管生成的关系。方法采用免疫组织化学法检测HGF及其受体c—met在113例NSCLC癌组织中的表达水平;应用D2—40进行淋巴管染色,计数微淋巴管密度（LMVD）;分析HGF及其受体c-met与LMVD之间的关系。结果HGF及c-met阳性染色主要位于NSCLC癌细胞的胞膜和胞质中,阳性表达率明显高于正常肺组织（67．3％、74．3％与20．0％、25．0％）（u值分别为4．008、4．342,均P〈0．05）。HGF、c—met的表达与患者的年龄、性别、肿瘤大小、组织学类型、分化程度均无关,而与TNM分期、淋巴结转移有关。HGF和c．met阳性表达的NSCLC患者较阴性者有更高的LMVD（HGF：16．3051±5．3753比10．9934±4．9668,t=4．58,P〈0．05;c—met：15．6692±5．5386比11．3700±5．3875,t=3．97,P〈0．05）。结论HGF及其受体c-met在NSCLC中高表达并与LMVD及淋巴结转移密切相关,提示HGF及其受体c-met在NSCLC淋巴管生成及淋巴转移方面起重要作用,为临床肺癌的诊断、防治和新药开发提供了新的靶向目标。     

EGFR-TKIs联合化疗在晚期非小细胞肺癌中的应用

晚期非小细胞肺癌（NSCLC）的治疗需首先明确其组织学类型与分子学特征。若存在表皮生长因子受体（EGFR）基因突变或渐变性淋巴瘤激酶（ALK）基因融合,应首选分子靶向药物治疗。但分子靶向治疗药物并未改善晚期患者的总生存,如何提高晚期NSCLC患者的总生存是目前临床医生关注的热点。表皮生长因子受体酪氨酸激酶抑制剂（EGFR-TKIs）与含铂双药交替使用模式作为晚期NSCLC的一线治疗方案,可能将明显延长EGFR阳性突变患者总生存时间。本文就小分子酪氨酸激酶抑制剂联合化疗治疗NSCLC患者、方式及其疗效的研究进展进行综述。      

EGFR基因突变与非小细胞肺癌靶向治疗研究进展

表皮生长因子受体（epidermal growth factor receptor,EGFR）在非小细胞肺癌（non-small cell lung cancer,NSCLC）常过度表达,EGFR突变常发生在外显子18～21,与EGFR分子靶向药物的反应敏感性相关。本文就EGFR基因在NSCLC中的突变及其靶向治疗进展做一综述。     

EGFR基因检测在非小细胞肺癌诊疗应用中的新进展

表皮生长因子受体（EGFR）是近年来关于非小细胞肺癌（NSCLC）发病机制中新的细胞分子受体,针对EGFR基因突变研究出的分子靶向药物是治疗NSCLC策略中成功有效的靶点途径,与传统一、二线化疗方案相比,其具有精准杀伤肿瘤细胞,对机体正常细胞损伤小,不良反应较少等优点,从而延长了NSCLC患者的生存期,并提高了生活质量。然而近年来的研究提示,分子靶向药物的耐药性对其持续精准治疗的有效性构成了严重影响。本文就EGFR基因的生物学特性,基因突变及与NSCLC的关系作一综述,并探讨EGFR受体在未来NSCLC治疗领域中的前景。     

分子基因指标对非小细胞肺癌靶向治疗的预测作用

随着众多靶向治疗药物进入非小细胞肺癌(NSCLC)的治疗指南或各期临床试验,许多研究者对分子基因指标在预测NSCLC靶向治疗疗效中的作用进行了深入研究.表皮生长因子受体(EGFR)基因突变检测指导EGFR酪氨酸激酶抑制剂(EGFR-TKI)的选择就是一个良好的开端.根据分子基因指标选择个体化的治疗方案,将是今后一段时间的重要研究方向,也是提高NSCLC治疗水平、延长患者生存的关键措施.随着靶向治疗研究的深入,相信会有更多的分子基因指标指导个体化治疗的制定.     

表皮生长因子受体酪氨酸激酶抑制剂与非小细胞肺癌的治疗

 表皮生长因子受体酪氨酸激酶抑制剂（EGFR-TKI）是一类高效低毒的抗肿瘤分子靶向药物,因其独特的疗效和良好的耐受性在非小细胞肺癌（NSCLC）治疗中成为研究的热点,在NSCLC的一线、二线或三线的辅助治疗中均有一定地位。随着研究的深入细化,EGFR TKI的适应证不断扩大,术前新辅助治疗可能成为一种新的治疗模式。     

肺癌分子分型与靶向治疗研究进展

随着肺癌发生、发展和预后相关分子机制研究的不断深入,肺癌靶向治疗取得了较大的进展,每一种分子分型的发现都会带来相应靶向药物的研究。2004年表皮生长因子受体(epidermal growth factor receptor,EGFR)基因在非小细胞肺癌中的发现,为我们带来了EGFR突变高度敏感有效的酪氨酸激酶抑制剂(tyrosine kinase inhibitor,TKI)。2007年棘皮类微管相关样蛋白-4-间变型淋巴瘤激酶(EML4-ALK)融合基因的出现为肺癌的分子发展带来了新的有效靶点。目前多个肺癌分子靶点及其靶向药物正在研究中。本文旨在回顾并总结肺癌分子分型及其靶向治疗的研究进展。     

The METeoric rise of MET in lung cancer

Over the years, there has been a continuous increase in clinically relevant driver mutations in patients with non–small cell lung cancer (NSCLC). Among these, dysregulated activation of the MET tyrosine kinase receptor has gained importance due to the recent development of quite effective treatments. MET dysregulation encompasses a heterogeneous array of alterations leading to the prolonged activation of the cellular MET (c-MET or MET) receptor and downstream proliferation pathways. It can arise through several mechanisms, including gene amplification, overexpression of the receptor and/or its ligand hepatocyte growth factor, and the acquisition of activating mutations. MET mutations are found in approximately 3% to 5% of patients with NSCLC, mainly adenocarcinoma, and are overrepresented in the sarcomatoid subtype. De novo MET amplifications are found in 1% to 5% of NSCLC cases, also predominantly in adenocarcinoma. In the current review, the authors discussed the biology of MET, how to diagnose clinically relevant alterations, and the rising clinical importance of these alterations in light of the emergence of multiple targeted therapies, both within the context of MET as a driver of resistance and in its own right.     

Targeting epidermal growth factor receptor in lung cancer: Perspective from the Asia–Pacific region

The epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase of the ErbB family that is frequently overexpressed in non‐small cell lung cancer (NSCLC), and has been identified as a novel therapeutic target for lung cancer. The development of small molecule EGFR‐tyrosine kinase inhibitors (TKI) such as gefitinib and erlotinib has resulted in paradigm shift in the treatment of advanced NSCLC. The impact of EGFR‐TKI in the treatment of NSCLC is even greater in Asia–Pacific region because one of the greatest clinical benefits of EGFR‐TKI has been seen in patients of East Asian ethnicity. The discovery of somatic mutations in EGFR‐tyrosine kinase domain has so far answered some, but not all, of the questions regarding the clinical response to EGFR‐TKI in NSCLC. In addition, other molecular profiles such as KRAS mutations have also been found to play an important role in EGFR targeted therapy. In this article, we review EGFR targeted therapy in NSCLC with the focus on perspective from the Asia–Pacific region.     

A selective small molecule c-MET Inhibitor, PHA665752, cooperates with rapamycin.

PURPOSE: c-MET is believed to be an attractive receptor target for molecular therapeutic inhibition. TPR-MET, a constitutively active oncogenic variant of MET, serves as excellent model for testing c-MET inhibitors. Here, we characterized a small molecule c-MET inhibitor, PHA665752, and tested its cooperation with the mammalian target of rapamycin inhibitor as potential targeted therapy. EXPERIMENTAL DESIGN: The effect of PHA665752 treatment was determined on cell growth, motility and migration, apoptosis, and cell-cycle arrest of TPR-MET-transformed cells. Moreover, the effect of PHA665752 on the phosphorylation on MET, as well as its downstream effectors, p-AKT and p-S6K, was also determined. Finally, growth of TPR-MET-transformed cells was tested in the presence of PHA665752 and rapamycin. H441 non-small cell lung cancer (NSCLC) cells (with activated c-Met) were also tested against both PHA665752 and rapamycin. RESULTS: PHA665752 specifically inhibited cell growth in BaF3. TPR-MET cells (IC(50) < 0.06 micromol/L), induced apoptosis and cell cycle arrest. Constitutive cell motility and migration of the BaF3. TPR-MET cells was also inhibited. PHA665752 inhibited specific phosphorylation of TPR-MET as well as phosphorylation of downstream targets of the mammalian target of rapamycin pathway. When combined with PHA665752, rapamycin showed cooperative inhibition to reduce growth of BaF3. TPR-MET- and c-MET-expressing H441 NSCLC cells. CONCLUSIONS: PHA665752 is a potent small molecule-selective c-MET inhibitor and is highly active against TPR-MET-transformed cells both biologically and biochemically. PHA665752 is also active against H441 NSCLC cells. The c-MET inhibitor can cooperate with rapamycin in therapeutic inhibition of NSCLC, and in vivo studies of this combination against c-MET expressing cancers would be merited.     

非小细胞肺癌的分子靶向治疗研究进展

肺癌是全球最常见的几种恶性肿瘤之一.近年来, EGFR、EML4-ALK、K-Ras、BRAF、C-MET、PIK3CA等越来越多的癌驱动基因被发现,以EGFR-TKIs为代表的靶向药为肺癌临床治疗带来新进展,但是大部分患者经靶向治疗后都会产生耐药,疗效仍不能满意.因此,基于肺癌基因驱动的机制探索及多靶点联合治疗是未来研究的方向.     

非小细胞肺癌人群中c-MET基因的扩增检测

目的：c-MET基因扩增是非小细胞肺癌对EGFR TKIs（吉非替尼或厄罗替尼）产生耐药的主要机制之一。本研究探讨没有接受TKIs治疗与TKIs治疗后耐药的NSCLC中c-MET基因的扩增是否存在差异。方法:获得55例术后非小细胞肺癌（NSCLC）的肿瘤组织（基线组）以及23例对TKIs耐药的肿瘤组织（耐药组）后,通过激光显微切割筛选癌细胞后提取基因组DNA,实时荧光定量PCR TaqMan探针法检测所有标本的c-MET基因的拷贝数。 结果:1.基线组和耐药组的临床病理特征均与c-MET基因的扩增无关。2.基线组中c-MET基因扩增阳性率为5.5% (3/55);耐药组的c-MET基因扩增阳性率为21.7% (5/23)。两组之间有统计学差异（Fisher精确概率法,P=0.045）。3.在7例获得TKI治疗前后肿瘤组织的NSCLC中,TKI治疗前没有出现c-MET的基因扩增,TKI治疗后有2例患者出现了c-MET的基因扩增（2/7）。TKI治疗前后的c-MET基因扩增差异无统计学意义。结论:NSCLC的临床病理特征不能预测c-MET基因扩增;在没有接受EGFR TKIs治疗的NSCLC中,c-MET基因扩增仅为少见事件。但经过吉非替尼或厄罗替尼治疗后出现耐药情况NSCLC中,部分患者的c-MET基因出现扩增。     

Clinicopathologic and Molecular Features of Epidermal Growth Factor Receptor T790M Mutation and c-MET Amplification in Tyrosine Kinase Inhibitor-resistant Chinese Non-small Cell Lung Cancer

To investigate the clinicopathologic and molecular features of the T790M mutation and c-MET amplification in a cohort of Chinese non-small cell lung cancer (NSCLC) patients resistant to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). EGFR TKI-resistant NSCLC patients (n?=?29) and corresponding tumor specimens, and 53 samples of postoperative TKI-naïve NSCLC patients were collected. EGFR exon 19, 20, and 21 mutations were analyzed. And c-MET gene copy number was determined. The EGFR T790M mutation in exon 20 was not detected in the population of 53 TKI-naïve patients, but found in 48.3% (14/29) of the enrolled TKI-resistant patients. c-MET was amplified in 3.8% (2/53) of the TKI-naïve NSCLC patients and highly amplified in 17.2% (5/29) of the cohort. Most of T790M mutations were frequently associated with non-smoker, adenocarcinoma and EGFR activating mutations. Three male patients with T790M mutation occurred with wild-type EGFR, and were resistant to the treatments following TKI resistance. Features of c-MET amplification in TKI-naïve patients were indistinguishable from TKI-resistant patients. In the group of wild-type EGFR, patients with T790M mutation had median progression free survival (PFS) and overall survival (OS) as 9.6 months and 12.6 months, respectively; whereas the median PFS and OS of c-MET amplified patients was 4.1 months and 8.0 months, respectively. These results suggest that EGFR T790M mutation and c-MET amplification can occur in TKI-resistant NSCLC with wild-type EGFR, and these genetic defects might be related to different survival outcome. c-MET amplification in TKI-naïve or -resistant patients might share similarities in clinicopathologic features.     

非小细胞肺癌脑转移治疗进展

非小细胞肺癌(NSCLC)脑转移的治疗方法包括激素、抗惊厥药物治疗、手术、放疗、化疗.近年来分子靶向治疗如表皮生长因子(EGFR)酪氨酸激酶抑制剂(TKI)成为NSCLC脑转移的新的治疗选择.     

Mechanisms of resistance to EGFR tyrosine kinase inhibitors gefitinib/erlotinib and to ALK inhibitor crizotinib

The discovery of several molecular alterations that underlie non-small cell lung cancer (NSCLC) pathogenesis has led to the development of targeted therapies. In particular, gefitinib and erlotinib have become the standard of care in patients harboring epidermal growth factor receptor mutations, while crizotinib showed an impressive efficacy in patients with ALK-positive NSCLC. Nevertheless, the occurrence of clinical resistance limits the long term results of these novel agents. The identification of the molecular mechanisms responsible for acquired resistance to targeted therapy is crucial in order to pursue the creation of rational strategies to overcome resistance. In the current review, we will focus on the acquired resistance mechanisms to EGFR-TKIs and crizotinib and the therapeutic strategies currently under study to overcome resistance.     

Targeted agents in non-small cell lung cancer (NSCLC): clinical developments and rationale for the combination with thoracic radiotherapy

In recent years there has been undoubted progress in the evaluation and development of targeted agents for non-small cell lung cancer (NSCLC). A major contributor has been the discovery of molecular subtypes harbouring a critical oncogenic driver mutation, specifically sensitizing mutations in the epidermal growth factor receptor (EGFR) gene and the EML4-ALK gene translocation. Radiotherapy is a cornerstone of therapy for the curative intent treatment of early stage, localized disease; and for the palliation of symptoms in advanced, metastatic disease. In this molecular targeted era there is limited understanding of how best to combine targeted agents with radiotherapy and in general clinical studies with radiotherapy have lagged behind studies of targeted agents with chemotherapy. Here we summarise the progress made to date and highlight future directions.