Role of Diabetes in Development of Renal Cell Carcinoma

糖尿病在肾细胞癌发展中的作用

• 批准号: 8245579
• 负责人: Samy Lewiz Habib
• 金额: --
• 依托单位: SOUTH TEXAS VETERANS HEALTH CARE SYSTEM
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-04-01 至 2014-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8245579
• 关键词: 1-Phosphatidylinositol 3-Kinase; 8-Oxo-2' -Deoxyguanosine; 8-hydroxyguanosine; Active Sites; Acute; Agonist; Alleles; American; Animals; Biological Markers; Blood specimen; Breeding; Cancer Etiology; Cancer Patient; Cells; Cessation of life; Chronic; Colon; Conventional (Clear Cell) Renal Cell Carcinoma; DNA; DNA Damage; DNA Repair; DNA Repair Enzymes; DNA glycosylase; Data; Development; Diabetes Mellitus; Diagnosis; Diagnostic Neoplasm Staging; Down-Regulation; Endometrium; Enzymes; Epithelial Cells; Family member; Fibroblasts; Frequencies; General Population; Generations; Genes; Glucose; Goals; High Pressure Liquid Chromatography; Human; Hyperglycemia; Incidence; Kidney; Kidney Neoplasms; Knockout Mice; Liver; Loss of Heterozygosity; Magnetic Resonance Imaging; Malignant Neoplasms; Measures; Messenger RNA; Military Personnel; Mus; Mutagenesis; Mutation; NADPH Oxidase; OGG1 gene; Organ; Pancreas; Pathway interactions; Patients; Persons; Phosphorylation; Population; Production; Proteins; Raptors; Rattus; Reactive Oxygen Species; Recording of previous events; Regulation; Renal Cell Carcinoma; Renal carcinoma; Reporter Genes; Risk; Role; Sampling; Screening for cancer; Screening procedure; Severities; Shuttle Vectors; Signal Transduction; Sirolimus; Small Interfering RNA; Solid Neoplasm; Specimen; Staining method; Stains; Testing; Texas; Time; Tissues; Transfection; Tuberous Sclerosis; Tuberous sclerosis protein complex; Tubular formation; Tumor Burden; Tumor Suppressor Genes; Tumor Suppressor Proteins; Tumor stage; United States; Urologic Cancer; Veterans; Western Blotting; carcinogenesis; diabetic; diabetic patient; diabetic rat; enzyme activity; high risk; human FRAP1 protein; human TSC2 protein; loss of function; loss of function mutation; mRNA Expression; mortality; mouse model; non-diabetic; oxidative DNA damage; promoter; public health relevance; research study; tumor; tumorigenesis

DESCRIPTION (provided by applicant): Rationale: Patients with diabetes are at higher risk than the general population of developing cancer of the urinary tract, liver, pancreas, colon, endometrium and kidney. Diabetes and hyperglycemia are associated with enhanced production of reactive oxygen species and induce DNA damage by several mechanisms. 8-Oxodeoxyguanine (8-oxodG) a major form of oxidative DNA damage has been implicated in early carcinogenesis. The DNA repair enzyme that recognizes and excises 8-oxodG is 8- oxoG-DNA glycosylase (OGG1). Deficiency in OGG1 has important functional consequences, compromising the ability of cells to repair DNA. Indeed, loss of heterozygosity at the OGG1 allele was found in human renal clear cell carcinoma (RCC) identifying loss of OGG1 function as a possible contributor to tumorigenesis in the kidney. Our preliminary data show that 8-oxodG levels are increased in kidney tissue of diabetic animal and human. In addition, we found that mutation in Ser326, the active site of OGG1 enzyme is increased in DNA blood samples from diabetic patients. One of the tumor suppressor genes involved in renal carcinogenesis is tuberous sclerosis gene (TSC2), which encodes tumor suppressor protein, tuberin. Eker rats harboring mutations in TSC2 develop spontaneous renal tumors at a very high incidence. We showed also that loss of function of the tumor suppressor gene, tuberous sclerosis complex 2 (TSC2), which encodes the protein tuberin, is associated with loss of function and mutations of OGG1 gene and accumulation of significant amounts of 8-oxodG in animal and human kidney tissues. Certain agonists activate PI-3 kinase and Akt, which stimulate tuberin phosphorylation resulting in its inactivation. Our preliminary studies show that incubation of rat renal proximal tubular cells (the cell origin of renal cell carcinoma) in high glucose results in increased reactive oxygen species (ROS) enhanced tuberin phosphorylation and decreased OGG1 expression. We also find that tuberin phosphorylation is increased in kidneys of diabetic rat. This is associated with increased levels of 8-oxodG. We have screened 500 kidney tumors from RCC patients and found that 25% of them has a history with diabetes. The mechanism(s) by which patients with diabetes are predisposed to cancer are not known. Hypothesis: We hypothesize that the increased production of ROS in diabetic subjects phosphorylates and inactivates tuberin, activates mTORC1 and/or mTORC2 resulting in downregulation of the DNA repair enzyme 8-oxoG-DNA glycosylase (OGG1) and accumulation of 8-oxodG. 8-OxodG enhances mutagenesis and predisposes the kidney and other organs to cancer. To explore our hypothesis we propose the following specific aims: SPECIFIC AIM 1: To determine the mechanism by which high glucose down-regulates OGG1 in proximal tubular cells, the cell origin of renal cell carcinoma. SPECIFIC AIM 2: To explore the effect of diabetes on the rate of development and severity as well as on the mutation frequency of renal cell carcinoma in the TSC-2 heterozygous rat and OGG1-/- mouse models. SPECIFIC AIM 3: To determine the levels of oxidative DNA damage (8-oxodG), OGG1 (protein, activity and mRNA) expression, the incidence of Ser326 mutation in OGG1, and levels of Akt, tuberin, S6K phosphorylation and downstream signals of mTOR in kidney tissue from patients with diabetes, patients with kidney cancer as well as patients with kidney cancer and diabetes. PUBLIC HEALTH RELEVANCE: The renal cell carcinoma (RCC) is one of the most lethal kidney cancers and is the sixth leading cause of cancer deaths. Every year approximately 40,000 Americans are diagnosed with RCC including military personnel, their family members, and U.S. Veteran population. More than 12,000 deaths in the United States are caused by RCC. Patients with diabetes are at higher risk than the general population of developing certain malignancies including kidney. Cancer contributes approximately 13% to mortality in diabetic patients. In Texas, an estimated of 1.9 million persons have been diagnosed with diabetes. The increasing the incidence of diabetes in our population will increase the risk of solid tumors including RCC. Our goal is to identify the mechanism by which diabetes accelerate tumor formation in kidney and other organs and validate 8-oxodG and OGG1 mutation(s) as new biomarkers for screening the diabetic subjects for early detection of cancer.

描述（由申请人提供）： 理由：糖尿病患者的风险高于尿路，肝脏，胰腺，结肠癌，子宫内膜和肾脏的一般人群。糖尿病和高血糖与活性氧的产生增强有关，并通过多种机制诱导DNA损伤。 8-氧化氧化物（8-oxoDG）氧化性DNA损伤的主要形式与早期致癌作用有关。识别和切除8-OXODG的DNA修复酶是8- oxog-DNA糖基化酶（OGG1）。 OGG1缺乏具有重要的功能后果，从而损害了细胞修复DNA的能力。实际上，在人肾透明细胞癌（RCC）中发现了OGG1等位基因杂合性的丧失，从而确定OGG1的损失是导致肾脏肿瘤发生的可能因素。我们的初步数据表明，在糖尿病动物和人类的肾脏组织中，8-氧气水平升高。此外，我们发现在Ser326中的突变，在糖尿病患者的DNA血液样本中，OGG1酶的活性位点增加了。参与肾脏致癌的肿瘤抑制基因之一是结节硬化基因（TSC2），它编码肿瘤抑制蛋白Tuberin。在TSC2中携带突变的Eker大鼠以很高的发病率形成自发的肾肿瘤。我们还表明，编码蛋白结核素的肿瘤抑制基因的功能丧失，结节硬化症复合物2（TSC2）与功能丧失和OGG1基因的突变以及在动物和人肾脏组织中的8-氧化物的突变有关。某些激动剂激活PI-3激酶和AKT，这会刺激结核素磷酸化，从而导致其失活。我们的初步研究表明，在高葡萄糖中孵育大鼠肾脏近端管状细胞（肾细胞癌的细胞起源）会导致活性氧（ROS）增强的结核蛋白磷酸化和OGG1表达降低。我们还发现，糖尿病大鼠肾脏中的结核素磷酸化增加了。这与8-氧气的水平升高有关。我们已经筛选了来自RCC患者的500个肾脏肿瘤，发现其中25％的肾脏患有糖尿病病史。尚不清楚使糖尿病患者容易患癌症的机制。假设：我们假设糖尿病受试者中ROS的产生增加磷酸化并使Tuberin失活，激活MTORC1和/或MTORC2，导致DNA修复酶的下调8-oxog-DNA糖基酶（OGG1）和8-oxodg的积累。 8-OXODG增强了诱变，并使肾脏和其他器官易受癌症。为了探讨我们的假设，我们提出了以下特定目的：特定目的1：确定高葡萄糖下调OGG1近端管状细胞（肾细胞癌的细胞起源）的机制。具体目的2：探索糖尿病对TSC-2杂合大鼠和OGG1 - / - 小鼠模型中肾细胞癌的发育和严重程度以及对肾细胞癌的突变频率的影响。特定目的3：确定氧化性DNA损伤（8-oxoDG），OGG1（蛋白质，活性和mRNA）的表达，OGG1中Ser326突变的发生率以及AKT，TUBERIN，TUBERIN，TUBERIN，TUBERIN，TUBOSHIN，磷酸化和MTOR的糖尿病患者的MTOR和下游信号以及肾脏癌症患者以及肾脏癌症患者以及肾脏癌症患者以及肾脏癌症的患者。 公共卫生相关性： 肾细胞癌（RCC）是最致命的肾脏癌症之一，是癌症死亡的第六个主要原因。每年约有40,000名美国人被诊断出患有RCC，包括军事人员，其家人和美国退伍军人人口。在美国，超过12,000人死亡是由RCC造成的。糖尿病患者的风险要高于发展某些恶性肿瘤在内的一般人群。癌症对糖尿病患者的死亡率约为13％。在德克萨斯州，估计有190万人被诊断出患有糖尿病。糖尿病在我们人群中的发生率的增加将增加包括RCC在内的实体瘤的风险。我们的目标是确定糖尿病在肾脏和其他器官中加速肿瘤形成的机制，并验证8-OXODG和OGG1突变作为筛查糖尿病患者早期发现癌症的新生物标志物。