The role of SEPT9 in cell proliferation and oncogenesis

SEPT9在细胞增殖和肿瘤发生中的作用

基本信息

批准号：
7183462
负责人：
ELIZABETH M. PETTY
金额：
$ 30.01万
依托单位：
UNIVERSITY OF MICHIGAN AT ANN ARBOR
依托单位国家：
美国
项目类别：
财政年份：
1997
资助国家：
美国
起止时间：
1997-09-08 至 2010-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7183462
关键词：
Abnormal Cell Agar Allelic Imbalance Anchorage-Independent Growth Aneuploidy Animals Apoptosis Apoptotic Breast Breast Adenocarcinoma Breast Cancer Cell Breast Cancer Model Cell Cycle Cell Cycle Progression Cell Cycle Regulation Cell Nucleus Cell Proliferation Cell division Cells Cellular Morphology Characteristics Chromosome Band Chromosome Banding Clinic Clinical Clinical Management Colon Carcinoma Condition Contact Inhibition Coupled Cytokinesis Data Depth Development Ectopic Expression Epithelial Cells Exons Family GTP Binding Genetic Genome Stability Genomic Instability Giant Cells Gland Goals Growth Homologous Gene Human Image Immunocompromised Host In Vitro Kinetics Lead Life Literature Localized Malignant - descriptor Malignant Neoplasms Malignant neoplasm of ovary Mammalian Cell Mammary Neoplasms Mammary Tumorigenesis Mammary gland Microfilaments Modeling Molecular Morphology Mouse Mammary Tumor Virus Mus Mutagenesis Names Nuclear Nutrient Oncogenes Oncogenic Orthologous Gene Outcome Pathway interactions Patients Pattern Phenotype Play Ploidies Protein Family Protein Isoforms Protein Overexpression Proteins Proto-Oncogenes RNA Splicing Rate Regulation Research Personnel Role S-Phase Fraction SCID Mice Sampling Studies Small Interfering RNA Somatic Cell T-Cell Lymphoma Testing Tetanus Helper Peptide Therapeutic Time Tissues Transcript Transgenes Transgenic Model Transgenic Organisms Tumorigenicity Variant Yeasts alpha Tubulin cancer cell carcinogenesis clinically significant immunocytochemistry in vitro Model in vivo innovation insight intracellular protein transport leukemia malignant breast neoplasm malignant phenotype member mouse model novel ovarian neoplasm pro-apoptotic protein prognostic programs promoter protein localization location tumor tumorigenesis

项目摘要

DESCRIPTION (provided by applicant): A classic feature of carcinogenesis is aberrant cell cycle regulation but little is known about how abnormal cell division contributes to malignant progression. Human SEPT9 belongs to a highly conserved eukaryotic family of GTP binding septin proteins important in cell division. In yeast, septins are coupled to cell cycle progression and are critical for normal morphology. Mammalian SEPT9 is required for normal somatic cell division. SEPT9 is highly homologous to Sept9/Sint1, a murineproto-oncogeneinvolvedin T-cell lymphomas that is overexpressed in murine models of mammary adenocarcinomas. We originally cloned SEPT9 from a region of allelic imbalance in breast cancers and have subsequently demonstrated SEPT9 amplification in breast cancer cells. We have also observed preferential expression of an alternatively spliced variant, SEPT9v1, in breast cancer cells. Stable ectopic expression of SEPT9v1 studied to date in vitro models resulted in increased growth kinetics, altered cell morphology, increased foci formation, increased invasiveness, abnormal cell division, nuclear mis-localization of the protein, and aneuploidy. SEPT9 was also identified as an MIL fusion partner in leukemia cells. Taken together, findings of: (1) an essential role for SEPT9 in cell division; (2) SEPT9 amplification and preferential expression of SEPT9v1 in breast cancer cells; (3) an altered cell phenotype with increased proliferation, invasiveness, foci formation, and aneuploidy when SEPT9v1 variant is ectopically expressed; and (4) homology to an oncogenic murine ortholog overexpressed in breast cancer provide compelling support for our hypothesis that increased expression of SEPT9v1, and possibly additional SEPT9 variants, is associated with abnormal cell division and malignant progression in mammary epithelial cells. To test this hypothesis we will: (1) determine if cellular levels of SEPT9v 1 in an archival panel of well-characterized primary and metastatic mammary tumors correlate with poor prognostic clinic pathological variables clinical outcome; (2) analyze in vitro epithelial cell culture and in vivo tumorigenicity models to determine how increased SEPT9v1 impacts cell proliferation, growth characteristics, invasiveness, apoptosis, cell morphology, and genomic stability as related to malignant progression; and (3) evaluate how in vivo overexpression of SEPT9v1 impacts normal mammary gland development and malignant potential by constructing and analyzing tissue specific and conditional transgenic mouse models, including crosses to other transgenic murine models of breast cancer. Results will provide insights into how increased SEPT9 v1 expression impacts cell division and tumorigenesis in mammary epithelial cells, which may have significant prognostic and/or therapeutic implications.

描述（由申请人提供）：癌变的经典特征是异常的细胞周期调节，但对异常细胞分裂如何促进恶性进展知之甚少。人类SEPT9属于在细胞分裂中重要的GTP结合Septin蛋白的高度保守的真核家族。在酵母中，septins耦合到细胞周期进程，对于正常形态至关重要。正常的体细胞分裂需要哺乳动物SEPT9。 SEPT9与Sept9/Sint1高度同源，Sept9/sint1是一种鼠 - 核苷拟南芥T细胞淋巴瘤，在乳腺腺癌的鼠模型中过表达。我们最初是从乳腺癌等位基因失衡区域的Sept9克隆的，随后证明了乳腺癌细胞中的SEPT9扩增。我们还观察到在乳腺癌细胞中替代剪接的变体Sept9v1的优先表达。迄今为止在体外模型中研究的SEPT9V1的稳定异位表达导致生长动力学增加，细胞形态的改变，焦点形成增加，侵入性增加，细胞分裂异常，蛋白质的核分解蛋白质和非整倍性。 SEPT9也被确定为白血病细胞中的MIL融合伴侣。两者合计：（1）SEPT9在细胞分裂中的重要作用；（2）SEPT9在乳腺癌细胞中SEPT9V1的扩增和优先表达；（3）当Sept9V1变体现有表达时，随着增殖，侵袭性，焦点形成和非整倍性的增加而改变的细胞表型；（4）与乳腺癌过表达的致癌鼠直系同源物的同源性为我们的假设提供了令人信服的支持，即增加SEPT9V1的表达，可能是其他Sept9变体，与乳腺上皮细胞中异常细胞分裂和恶性进展有关。为了检验该假设，我们将：（1）确定在特征良好的原发性和转移性乳腺肿瘤的档案板中SEPT9V 1的细胞水平是否与预后临床诊所病理变量较差的临床结果相关；（2）分析体外上皮细胞培养和体内肿瘤性模型，以确定增加的SEPT9V1如何影响细胞增殖，生长特征，侵袭性，凋亡，细胞形态和基因组稳定性以及与恶性进展有关的基因组稳定性；（3）评估SEPT9V1的体内过表达如何通过构建和分析组织特异性和条件转基因小鼠模型（包括与其他转基因鼠类乳腺癌模型的交叉）来影响正常的乳腺发育和恶性潜力。结果将提供有关SEPT9 V1表达增加如何影响细胞分裂和乳腺上皮细胞的肿瘤发生的见解，乳腺上皮细胞可能具有明显的预后和/或治疗意义。