Genetic Alterations in Lung Cancer

肺癌的基因改变

• 批准号: 7592705
• 负责人: Jonathan Scott Wiest
• 金额: $ 55.78万
• 依托单位: DIVISION OF BASIC SCIENCES - NCI
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/7592705
• 关键词: Accounting; Amino Acid Sequence; Amino Acids; Apoptotic; Biological Assay; Breast; Cancer Etiology; Cancer Patient; Cancer cell line; Cause of Death; Cell Line; Cells; Cessation of life; Characteristics; Chromosome Arm; Chromosomes; Clinical; Colon Carcinoma; DNA; DNA Sequence; Data; Disease; Disease Management; Disease Progression; Distant Metastasis; Down-Regulation; Early Diagnosis; Environmental Risk Factor; Event; Gene Expression; Gene Mutation; Genes; Health; Heart Diseases; Human; In Vitro; Individual; Inflammatory Response; Lead; Literature; Liver; Lung; Lung Neoplasms; MAP Kinase Kinase Kinase; MAP3K8 gene; Malignant Neoplasms; Malignant neoplasm of lung; Malignant neoplasm of thyroid; Measures; Missense Mutation; Mutate; Mutation; NF-kappa B; Newly Diagnosed; Nodule; Non-Small-Cell Lung Carcinoma; Northern Blotting; Numbers; Oncogenic; Open Reading Frames; Pathway interactions; Patients; Peptides; Phenotype; Play; Polyadenylation; Polymerase Chain Reaction; Population Group; Positioning Attribute; Prostate; Protein Kinase; Protein Overexpression; Public Health; Publishing; RNA; Range; Relative Risks; Reporting; Risk; Role; Sampling; Screening procedure; Signal Transduction; Signal Transduction Pathway; Smoker; Somatic Mutation; Southern Blotting; Spleen; Survival Rate; Systemic Therapy; Testing; Thymus Gland; Thyroid carcinoma; Time; Tobacco smoking; Transcript; Transcription Factor AP-1; Transfection; Tumor Biology; Tumor Suppressor Genes; Tumor Suppressor Proteins; United States; Up-Regulation; Woman; disorder risk; human MAP2K1 protein; human tissue; improved; in vivo; interest; lung small cell carcinoma; lung tumorigenesis; mRNA Expression; men; metaplastic cell transformation; mortality; neoplastic cell; novel; outcome forecast; protein expression; research study; size; smoking cessation; transcription factor; tumor; tumor progression; tumorigenesis; tumorigenic

Lung cancer is the leading cause of cancer related mortality in both men and women and remains a major health issue. More than 170,000 individuals will die from lung cancer in the coming year, more than breast, prostate and colon cancer combined. The majority of lung cancer cases is attributable to tobacco smoking and in some cases other environmental risk factors. Although the relative risk of developing lung cancer declines dramatically in smokers who quit, former smokers remain at risk for the disease. Several recent studies show that greater than 50% of newly diagnosed lung cancers occur in former smokers. Of the tumors detected in former smokers, nearly 50% occurred in patients who had quit for more than five years. It is estimated that there are approximately equal numbers of smokers and former smokers in the United States. Since smoking cessation is a major public health initiative, former smokers will increasingly account for a higher percentage of lung cancer cases. Thus, two high-risk population groups exist for lung cancer and improved disease management can be beneficial to both current and former smokers. Additionally the prognosis for lung cancer patients is very poor, and is due, in part, to the historical lack of effective early detection measures. TUMOR SUPPRESSOR GENES (TSG) ON CHROMOSOME 9P: Chromosome 9p deletions and alterations occur early and often in lung cancer. The p16/CDKN2 locus, located on 9p, is suspected to be the major tumor suppressor gene inactivated in this tumor type. However, we identified a region of homozygous deletion on the short arm of chromosome 9p. We proposed that the region harbors a TSG important in lung tumorigenesis. We furthered our analysis with 30 non-small cell lung cancer and 12 small cell lung cancer cell lines by screening them with 55 markers to identify new regions of homozygous deletion on chromosome 9p. Three novel non-contiguous homozygously deleted regions were detected and ranged in size from 840 Kb to 7.4 Mb. One of these regions led to the identification of a gene identified as TUSC1. Multiplex PCR and Southern blot confirmed the homozygous deletion of TUSC1. Northern blot analysis of TUSC1 demonstrated two transcripts of approximately 2 and 1.5 kb that are likely generated by alternative polyadenylation signals. Both transcripts are expressed in several human tissues and share an open reading frame encoding a peptide of 209 amino acids. Analyzing lung cancer cell lines for RNA and protein expression demonstrated down regulation of TUSC1 in several cell lines suggesting TUSC1 may play a role in tumorigenesis. DNA sequencing of the TUSC1 gene open reading frame detected missense mutations in 7 of 41 cell lines examined and we are currently analyzing matched tumor and normal lung cancer samples to determine if somatic mutations occur in TUSC1. Studies using lung tumor cell lines stably transfected with TUSC1 show reduced proliferation both in vitro and in vivo. Taken together, these data suggest that chromosome 9p may contain other tumor suppressor genes important in lung tumorigenesis and that TUSC1 may be a candidate TSG. Current studies will examine how induction of TUSC1 expression will alter the phenotype of cells in culture. THE MAP3K8 GENE IN LUNG TUMORIGENESIS: The MAP3K8 gene is a MAP kinase kinase kinase expressed in a variety of cells and found to be oncogenic and constitutively activated when altered at the 3 end. However, mutation of the gene appears to be a rare event in humans, but altered MAP3K8 expression is associated with multiple tumor types. MAP3K8 possesses the unique characteristic of activating multiple cascades, including both proliferative and apoptotic signal transduction pathways such as the MEK-1 and SEK-1 pathways, respectively. In NIH3T3 transfection assays utilizing lung tumor DNA, our lab identified a 3 alteration of MAP3K8 similar to the previous reports. We first hypothesized that MAP3K8 might be a target for mutation since we were the first group to report an activating mutation in a primary human tumor. However, it has become clear that mutations are not a common event in tumorigenesis for this gene. Subsequently we showed varied levels of expression of the gene in lung tumor cell lines. This led us to investigate other downstream pathways that could explain the tumorigenic potential of MAP3K8. These included transcription factor array analysis and protein kinase array experiments. We were able to confirm other reports in the literature demonstrating upregulation of NF-kappaB and AP-1 as well as identify other important transcription factors not reported in the literature. These and other experiments, as well as published reports lead us to modify our hypothesis that increased expression of MAP3K8 occur in lung cancer and contribute to disease progression. Real-time PCR demonstrated 7/17 non-small cell lung cancer (NSCLC) cell lines significantly increased MAP3K8 mRNA expression, with 3 cell lines over 50-fold greater that of normal lung cells. While 4/14 small cell lung cancer (SCLC) cell lines increased expression, the majority of SCLC cell lines decreased expression. We have recently shown that increased protein expression of MAP3K8 in these cell lines leads to hyperphosphorylation of its downstream target MEK-1. These data suggest MAP3K8 expression is altered in lung cancer cells lines and because of its role in the inflammatory response, MAP3K8 overexpression may be involved in tumor progression

肺癌是男性和女性癌症相关死亡的主要原因，并且仍然是一个主要的健康问题。明年将有超过17万人死于肺癌，超过乳腺癌、前列腺癌和结肠癌的总和。大多数肺癌病例可归因于吸烟，在某些情况下还可归因于其他环境风险因素。虽然戒烟者患肺癌的相对风险大幅下降，但前吸烟者仍有患肺癌的风险。最近的几项研究表明，超过50%的新诊断的肺癌发生在以前的吸烟者中。在前吸烟者中发现的肿瘤中，近50%发生在戒烟超过五年的患者中。据估计，在美国，吸烟者和前吸烟者的人数大致相同。由于戒烟是一项重大的公共卫生举措，因此前吸烟者在肺癌病例中所占的比例将越来越高。因此，存在两个肺癌高危人群，改善疾病管理对当前和以前的吸烟者都有益。此外，肺癌患者的预后非常差，部分原因是历史上缺乏有效的早期检测措施。染色体9 p上的肿瘤支持基因（TSG）：染色体9 p缺失和改变发生在肺癌的早期和经常发生。p16/CDKN 2位点位于9 p，被怀疑是该肿瘤类型中失活的主要抑癌基因。然而，我们确定了一个区域的纯合性缺失染色体9 p的短臂上。我们提出，该地区窝藏TSG在肺肿瘤发生的重要。我们进一步分析了30个非小细胞肺癌和12个小细胞肺癌细胞系，用55个标记筛选它们，以确定染色体9 p上纯合缺失的新区域。检测到三个新的非连续同源性缺失区域，大小范围从840 Kb到7.4 Mb。其中一个区域导致了被鉴定为TUSC 1的基因的鉴定。多重PCR和Southern杂交证实了TUSC 1基因的纯合性缺失。TUSC 1的北方印迹分析证明了两个大约2和1.5 kb的转录本，它们可能是由替代的多聚腺苷酸化信号产生的。这两种转录物在几种人体组织中表达，并且共享编码209个氨基酸的肽的开放阅读框。分析肺癌细胞系的RNA和蛋白质表达表明，TUSC 1在几种细胞系中下调，表明TUSC 1可能在肿瘤发生中起作用。TUSC 1基因开放阅读框的DNA测序检测到41个细胞系中的7个细胞系的错义突变，我们目前正在分析匹配的肿瘤和正常肺癌样本，以确定TUSC 1是否发生体细胞突变。使用稳定转染有TUSC 1的肺肿瘤细胞系的研究显示在体外和体内都降低了增殖。总之，这些数据表明，染色体9 p可能含有其他重要的肿瘤抑制基因在肺肿瘤的发生和TUSC 1可能是一个候选的TSG。目前的研究将检查TUSC 1表达的诱导如何改变培养中细胞的表型。肺肿瘤发生中的MAP 3 K8基因：MAP 3 K8基因是一种MAP激酶激酶，在多种细胞中表达，发现其具有致癌性，当3端改变时组成性激活。然而，该基因的突变在人类中似乎是罕见的事件，但MAP 3 K8表达的改变与多种肿瘤类型有关。MAP 3 K8具有激活多个级联的独特特性，包括增殖和凋亡信号转导途径，例如分别为MEK-1和SEK-1途径。在利用肺肿瘤DNA的NIH 3 T3转染试验中，我们的实验室鉴定了与先前报道相似的MAP 3 K8的3个改变。我们首先假设MAP 3 K8可能是突变的靶点，因为我们是第一个报告原发性人类肿瘤中激活突变的小组。然而，已经清楚的是，突变在该基因的肿瘤发生中不是常见事件。随后，我们发现该基因在肺肿瘤细胞系中的表达水平不同。这使我们研究了其他下游途径，可以解释MAP 3 K8的致瘤潜力。这些包括转录因子阵列分析和蛋白激酶阵列实验。我们能够证实文献中的其他报告，证明NF-κ B和AP-1的上调，以及确定其他重要的转录因子在文献中没有报道。这些和其他实验以及已发表的报告使我们修改了我们的假设，即MAP 3 K8的表达增加发生在肺癌中并有助于疾病进展。Real-time PCR显示7/17个非小细胞肺癌（NSCLC）细胞系的MAP 3 K8 mRNA表达显著增加，其中3个细胞系的MAP 3 K8 mRNA表达是正常肺细胞的50倍以上。虽然4/14的小细胞肺癌（SCLC）细胞系表达增加，但大多数SCLC细胞系表达降低。我们最近发现，在这些细胞系中，MAP 3 K8蛋白表达的增加导致其下游靶点MEK-1的过度磷酸化。这些数据表明，MAP 3 K8表达在肺癌细胞系中改变，并且由于其在炎症反应中的作用，MAP 3 K8过表达可能参与肿瘤进展