The Role of Peroxiredoxin1 & Reactive Oxygen Species in Breast Tumor Initiation

过氧化还原蛋白1的作用

基本信息

批准号：
8220850
负责人：
CAROLA ANKE NEUMANN
金额：
$ 29.69万
依托单位：
MEDICAL UNIVERSITY OF SOUTH CAROLINA
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-04-07 至 2012-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8220850
关键词：
Agar Aging Alleles Antioxidants Apoptosis Binding Bioluminescence Breast Cancer Etiology Catalytic Domain Cell Proliferation Cell Transplants Cells Complex Cysteine Development Environmental Carcinogens Epithelial Cells Exhibits Family Fatty acid glycerol esters Fibroblasts Future Growth Factor HRAS gene Hemolytic Anemia Human Hydrogen Peroxide In Vitro Incidence Induction of Apoptosis Investigation Ionizing radiation Lipids Malignant Neoplasms Mammary Neoplasms Mammary gland Mediating Membrane Membrane Potentials Mouse Mammary Tumor Virus Mus Mutation Nuclear Nuclear Localization Signal Nude Mice PTEN gene PTEN protein Peptide Signal Sequences Peptides Peroxidases Phosphatidylinositols Phosphoric Monoester Hydrolases Phosphorylation Phosphotransferases Play Predisposition Preventive Process Protein Dephosphorylation Puma Reactive Oxygen Species Regulation Role Signal Pathway Signal Transduction Testing Tobacco smoking Tumor Burden Tumor Suppression Tumor Suppressor Proteins Work base cell transformation cell type in vivo insight malignant breast neoplasm mitochondrial membrane mouse model novel oxidation prevent public health relevance radiation carcinogen tool tripolyphosphate tumor tumor initiation tumorigenesis

项目摘要

DESCRIPTION (provided by applicant): It is widely accepted that reactive oxygen species (ROS), such as H2O2 promote tumorigenesis. Consequently, there is a crucial need for a greater understanding of the mechanism of H2O2-mediated cancer development. We have shown that mice lacking one or two copies of the peroxidase Prdx1 die prematurely of hemolytic anemia and multiple cancers. Furthermore, cells and mice lacking Prdx1 show a higher incidence of transformation to H-RasV12 and ErbB-2 and H-RasV12-induced breast cancer. Fibroblasts and mammary epithelial cells lacking Prdx1 show higher phosphorylation of Akt on Ser473 and more inactive (oxidized) forms of the tumor suppressor PTEN. PTEN is readily inactivated via oxidation of the low pKa cysteine in its catalytic site. We found that Prdx1 binding to PTEN is essential to protect it from oxidation-induced inactivation. The Prdx1:PTEN complex is disrupted by H2O2, upon which Akt including its downstream signaling is activated resulting in a decrease in apoptosis. Therefore, our working hypothesis is that H2O2 inactivates PTEN lipid phosphatase activity due to a complex disruption of Prdx1:PTEN, thereby promoting Akt kinase-driven oncogenesis. We further hypothesize that Prdx1:PTEN binding is required for normal PTEN function, including its lipid phosphatase activity, nuclear stability and apoptosis induction. Specific Aim1 will determine the mechanisms by which H2O2 regulates the Prdx1:PTEN interaction to alter PTEN lipid phosphatase activity and Prdx1 peroxidase activity. We will define if H2O2-induced oxidation of either Prdx1 or PTEN disrupts or prevents the Prdx1:PTEN interaction and modulates PTEN lipid phosphatase activity and Prdx1 peroxidase activity. Specific Aim2 will examine if the Prdx1:PTEN interaction promotes tumor suppression by regulating PTEN or Akt dependent mechanisms. To complete this we will examine PTEN-induced tumor suppressive functions including apoptosis upon disrupting the Prdx1:PTEN interactions by using peptide interference in vitro and in vivo. Specific Aim3 will evaluate if nuclear Prdx1 promotes tumor suppression ErbB-2-induced breast cancer in mice. We have found that loss of Prdx1 decreases nuclear PTEN protein levels. We will therefore introduce Prdx1 fused to nuclear localization signal sequence into mammary epithelial cells isolated from Prdx1-/-MMTV-ErbB-2 mice and transplant cells into clear fad pads of NCR nude mice, to observe if nuclear Prdx1 decreases incidence of breast cancer or tumor burden. Mice lacking Prdx1 offer the first mouse model where loss of a peroxidase results in elevation of endogenous H2O2 thereby causing cancer. This mouse model mimics conditions where H2O2 levels are elevated as found in aging, tobacco smoking, ionizing radiation and environmental carcinogens. By studying breast cancer prone mice lacking Prdx1 we should help to find more specific preventive treatments in H2O2-induced breast cancer. PUBLIC HEALTH RELEVANCE: Studying the role of the peroxidase Prdx1 is inhibiting breast cancer promoting signaling pathways, will be an important tool in the future to develop eventually tumor preventive treatments.

描述（由申请人提供）：被广泛接受的是，活性氧（ROS），例如H2O2促进肿瘤发生。因此，至关重要的是要更深入地了解H2O2介导的癌症发展的机制。我们已经表明，缺乏过氧化物酶PRDX1的小鼠过早地死于溶血性贫血和多种癌症。此外，缺乏PRDX1的细胞和小鼠向H-RASV12和ERBB-2和H-RASV12诱导的乳腺癌转化的发生率更高。缺乏PRDX1的成纤维细胞和乳腺上皮细胞在SER473上显示出较高的Akt磷酸化，并且在肿瘤抑制剂PTEN上表现出更高的AKT和更多的非活性（氧化）形式。通过在其催化部位的低PKA半胱氨酸的氧化中，PTEN很容易被灭活。我们发现，PRDX1与PTEN的结合对于保护其免受氧化诱导的失活而至关重要。 H2O2破坏了PRDX1：PTEN复合物，其AKT在其中激活了包括其下游信号的AKT，从而导致凋亡减少。因此，我们的工作假设是H2O2由于PRDX1的复杂破坏而使PTEN脂质磷酸酶活性失活，从而促进了Akt激酶驱动的肿瘤发生。我们进一步假设正常PTEN功能需要PRDX1：PTEN结合，包括其脂质磷酸酶活性，核稳定性和凋亡诱导。特定的AIM1将确定H2O2调节PRDX1：PTEN相互作用以改变PTEN脂质磷酸酶活性和PRDX1过氧化物酶活性的机制。我们将定义H2O2诱导的PRDX1或PTEN的氧化是否破坏或防止PTEN相互作用并调节PTEN脂质磷酸酶活性和PRDX1过氧化物酶活性。特定的AIM2将检查PRDX1：PTEN相互作用是否通过调节PTEN或AKT依赖机制促进肿瘤抑制。为了完成此操作，我们将检查PTEN诱导的肿瘤抑制功能，包括通过在体外和体内使用肽干扰来破坏PRDX1：PTEN相互作用。特定的AIM3将评估核PRDX1是否促进了小鼠肿瘤抑制ERBB-2诱导的乳腺癌。我们发现PRDX1的损失降低了核PTEN蛋白水平。因此，我们将将融合到核定位信号序列的PRDX1引入从PRDX1 - / - MMTV-ERBB-2小鼠和移植细胞中分离的乳腺上皮细胞中，以观察核PRDX1是否会降低乳腺癌或肿瘤负担的发生率，以观察到核PRDX1。缺乏PRDX1的小鼠提供了第一个小鼠模型，其中过氧化物酶的丧失导致内源性H2O2升高，从而导致癌症。该小鼠模型模仿了H2O2水平在衰老，烟草吸烟，电离辐射和环境致癌物中升高的条件。通过研究缺乏PRDX1的乳腺癌小鼠，我们应该帮助您在H2O2诱导的乳腺癌中找到更具体的预防性治疗。公共卫生相关性：研究过氧化物酶PRDX1的作用正在抑制乳腺癌促进信号通路，将来将成为开发最终肿瘤预防治疗的重要工具。