Molecular Analysis Of Cell Cycle Control During Carcinogenesis

致癌过程中细胞周期控制的分子分析

• 批准号: 8336521
• 负责人: Richard Paules
• 金额: $ 109.26万
• 依托单位: NATIONAL INSTITUTE OF ENVIRONMENTAL HEALTH SCIENCES
• 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/8336521
• 关键词: ATM deficient; ATM function; Ataxia Telangiectasia; B-Cell Development; B-Lymphocytes; Biological Models; Breast; Caenorhabditis elegans; Cancer-Predisposing Gene; Cell Cycle; Cell Cycle Checkpoint; Cell Cycle Checkpoint Genes; Cell Cycle Regulation; Cell Survival; Cells; Cessation of life; Checkpoint kinase 1; Collaborations; DNA Damage; DNA Repair; DNA Repair Gene; DNA Repair Pathway; DNA-dependent protein kinase; Defect; Diploidy; Disease; Epithelial; Epithelial Cells; Etiology; Event; Exposure to; Fibroblasts; G1 Phase; G2 Phase; Gene Expression; Genes; Genetic Programming; Goals; Human; Individual; Injury; Ionizing radiation; Lymphocyte; Malignant Neoplasms; Mammary gland; Mediating; Messenger RNA; MicroRNAs; Molecular; Molecular Analysis; Mouse Strains; Mus; Mutate; Mutation; Neoplastic Cell Transformation; Oxidative Stress; Pathway interactions; Phosphotransferases; Physiological; Play; Population; Predisposition; Process; Protein Kinase; Radiation Induced DNA Damage; Research; Research Design; Role; S Phase; Signal Pathway; Signal Transduction; Specificity; Stress; Syndrome; Techniques; Toxic Environmental Substances; Ultraviolet Rays; carcinogenesis; cell type; gene repair; immune activation; insight; knock-down; member; novel; response; small hairpin RNA

The overall goal of the research of the group is to provide a better understanding of the regulatory networks that control critical cellular responses to environmental stresses. We are currently investigating cell cycle checkpoint responses to cellular damage from various environmental stresses and how defects in these responses can contribute to cancer. Intricate regulatory networks control stress-induced cell cycle checkpoints and these networks respond in a damage- and cell type-specific manner. Group members are presently studying the critical molecular events that regulate cell cycle checkpoint signaling following exposures to ionizing radiation (IR), ultraviolet (UV) radiation, oxidative stress and other environmental stresses. In addition, we are investigating the cellular specificity of these processes in normal human cells (e.g. diploid fibroblasts and normal breast epithelial cells) and cells with genetic alterations in cancer susceptibility genes, such as the gene mutated in ataxia telangiectasia (ATM). Three independent isogenic lines of normal and ATM-deficient breast epithelial cells have been established through stable shRNA knock-down techniques in order to obtain populations of mammary epithelial cells that differ only in their levels of ATM. In addition, isogenic normal and ATM-deficient mammary epithelial lines have been established that are deficient in the checkpoint kinase 1 (CHK1), as well as lines with a conditional depletion of the kinase function of the ATM and Rad3-related kinase (ATR). Studies of DNA damage signaling in these cells has provided novel mechanistic insight into the function of ATM, ATR, and CHK1 protein kinases and the DNA-dependent protein kinase (DNA-PK) in the G2 checkpoint response to ionizing radiation induced cellular damage. In studies performed in collaboration with Barry Sleckman and colleagues, we have investigated the gene expression responses and signaling pathways activated by genotoxic radiation-induced DNA damage in mouse pre-B cells that are from mouse strains that are deficient in various DNA damage response and repair genes. We have been able to show that in addition to the expected cell cycle checkpoint and DNA damage and repair responses, these double strand breaks also initiate, in part, an overlapping lymphocyte-specific genetic program that contributes to B-cell development and differentiation, as we had previously found following physiological Rag-mediated double strand breaks. We have also found that there is a cell-cycle dependent immune activation response following radiation induced DNA damage.

该小组研究的总体目标是更好地了解控制关键细胞对环境压力反应的调节网络。我们目前正在研究细胞周期检查点对各种环境压力造成的细胞损伤的反应，以及这些反应中的缺陷如何导致癌症。复杂的调控网络控制着应激诱导的细胞周期检查点，这些网络以损伤和细胞类型特异性的方式作出反应。小组成员目前正在研究暴露于电离辐射（IR）、紫外线（UV）辐射、氧化应激和其他环境应激后调节细胞周期检查点信号的关键分子事件。此外，我们正在研究这些过程在正常人类细胞（如二倍体成纤维细胞和正常乳腺上皮细胞）和具有癌症易感基因遗传改变的细胞（如失调性毛细血管扩张症（ATM）突变的基因）中的细胞特异性。为了获得仅在ATM水平上存在差异的乳腺上皮细胞群，通过稳定的shRNA敲除技术，建立了正常和ATM缺陷乳腺上皮细胞的三个独立等基因系。此外，已经建立了等基因正常和ATM缺陷的乳腺上皮细胞系，它们缺乏检查点激酶1 (CHK1)，以及ATM和rad3相关激酶（ATR）的激酶功能有条件缺失的细胞系。对这些细胞中DNA损伤信号的研究为ATM、ATR和CHK1蛋白激酶以及DNA依赖性蛋白激酶（DNA- pk）在电离辐射诱导的细胞损伤的G2检查点反应中的功能提供了新的机制见解。在与Barry Sleckman及其同事合作进行的研究中，我们研究了基因毒性辐射诱导的DNA损伤在小鼠前b细胞中激活的基因表达反应和信号通路，这些细胞来自缺乏各种DNA损伤反应和修复基因的小鼠菌株。我们已经能够证明，除了预期的细胞周期检查点和DNA损伤和修复反应外，这些双链断裂也在一定程度上启动了重叠的淋巴细胞特异性遗传程序，该程序有助于b细胞的发育和分化，正如我们之前在rag介导的生理双链断裂后发现的那样。我们还发现，辐射诱导的DNA损伤后存在细胞周期依赖的免疫激活反应。