Activation mutations in EGF receptor kinase have the advantages of cell physiology in the bronchiolar region : Implication of anti-apoptotic signals and lung tumorigenesis and metastasis.

背景：不断发展的分子靶向药物概念使癌症的治疗发生了革命性的变化。伊马替尼靶向bcr-abl嵌合体蛋白在血液系统恶性肿瘤中的首次成功，紧随其后的是针对实体肿瘤的药物，吉非替尼或厄洛替尼，靶向EGFR激酶的激活形式(缺失或L858R突变)。后者的独特之处在于：(1)该突变是肺腺癌所特有的；(2)该突变对三磷酸腺苷和抗细胞凋亡有很高的亲和力；(3)该突变在远东地区发病率较高。方法：选用PC9(EGFR缺失型)、11-18(EGFR L858R)和A549(EGFR野生型)细胞系，制备带有EGFR/wt、EGFR/del、EGFR/L858R的COS-7细胞。对体外信号转导和裸鼠体内转移模型进行Western印迹分析。表达芯片(AffymetrixU133 plus2.0)…结果：1.体外信号转导结果显示：(1)PC9在常规FCS培养液中具有结构性活性，而11-18或COS-7仅在隔夜饥饿后加入EGF后才在Tyr1068中发生磷酸化。(2)pEGFR/Tyr1068的检测顺序为COS-7/EGFR wt&gt；COS-7/EGFR del&gt；COS-7.2。颈静脉注射PC9(10‘6细胞)在2个月内仅在肺内形成肿瘤。给药1周后，用细胞追踪器标记PC9，发现细支气管区的微转移灶。基因芯片对PC9、11-18和A549细胞株的表达分析显示出两种特征模式：(1)PC9=11-18和gt；A549(ARHGAP29等)或PC9=11-18和lt；A549(Dkk1等)。(2)PC9&gt；11-18=A549(FOX03A等)或PC9&lt；11-18=A549(连环蛋白α1等)。体内可见细支气管区的微转移。在使用PC9、11-18和A549的微阵列表达分析中的两种特征模式表明，EGFR信号和生物学结果可能存在差异。较少

Backgrounds : The evolving concept of molecular targeting drugs has revolutionized the treatment of cancer. The first success of imatinib targeting the chimera protein of Bcr-abl in hematologic malignancies is followed by drugs for solid tumors, gefitinib or erlotinib, targeting the activation form of EGFR kinase (either deletion or L858R mutation). The latter is unique in facts that (1)Rthe mutation is specific for lung adenocarcinoma, (2)resulting in high affinity for ATP and anti-apoptosis, and (3) somatic but high incidence in far-east Orientals. We hypothesized that this specific EGFR mutation is selected because of the advantages in the respiratory bronchiolar regions.Methods : We used PC9 (EGFR deletion type), 11-18 (EGFR L858R) and A549 (EGFR wild type) cell lines and prepared COS-7 cells with EGFR/wt, EGFR/del, EGFR/L858R. Western blot analysis for in vitro signaling, and in vivo metastatic model using nude mice were performed. Expression microarray (Affymetrix U133 plus 2.0) … More analysis were conducted using 3 cell lines.Results : 1. In vitro signaling revealed that (1) while PC9 is constitutively active in usual FCS medium, 11-18 or COS-7 showed phosphorylation in Tyr1068 only after the addition of EGF after overnight starvation. (2) The pEGFR/Tyr1068 was detected in the order of COS-7/EGFR wt> COS-7/EGFR del>COS-7.2. PC9 (1O'6 cells) administered in the cervical vein resulted in tumors only in the lung in 2 months. Micro-metastatic lesions in the bronchiolar region were found using PC9 labeled with Cell Tracker 1 week after administration.3. Microarray expression analysis of PC9, 11-18, and A549 cell lines revealed two characteristic patterns: (1) PC9=11-18 > A549 (ARHGAP29 etc) or PC9=11-18 < A549 (DKK1 etc). (2) PC9 > 11-18=A549 (FOX03A etc) or PC9 < 11-18=A549 (catenin α 1 etc).Conclusion : Specific EGFR activation mutation showed distinct patterns of phosphrylation signaling. In vivo micro-metastasis was seen in the bronchiolar regions. Two characteristic patterns in the microarray expression analysis using PC9, 11-18, and A549 indicated the possible difference in the EGFR signaling and biological outcome. Less