Anti-tumor properties of curcumin in oral cancers: role of thioredoxin reductase

姜黄素在口腔癌中的抗肿瘤特性：硫氧还蛋白还原酶的作用

• 批准号: 7738540
• 负责人: Stephen William Tuttle
• 金额: $ 17.32万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-05-21 至 2011-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7738540
• 关键词: 3' Untranslated Regions; Adenovirus Vector; Affect; Alcohol consumption; Animal Model; Antioxidants; Apoptosis; Apoptotic; Biological Assay; Biological Availability; Biological Factors; Blood Circulation; C-terminal; Cancer cell line; Cell Death; Cell Line; Cells; Cervical; Cessation of life; Chemicals; Chemoprevention; Chemopreventive Agent; Clinical Trials; Covalent Interaction; Curcuma longa; Curcumin; Cysteine; DNA Insertion Elements; DNA Repair; Data; Diagnosis; Diet; Dominant-Negative Mutation; Dose; Electrons; Enzymes; Genes; Genetic Transcription; Genus Cola; Growth; Head and Neck Cancer; Head and Neck Squamous Cell Carcinoma; Human; Hydrogen Peroxide; Implant; In Vitro; Ionizing radiation; Knock-in Mouse; Length; Lesion; Luciferases; Malignant Epithelial Cell; Malignant Neoplasms; Measures; Mediating; Mediator of activation protein; Modification; Morbidity - disease rate; NADP; NADPH Oxidase; Nude Mice; Operative Surgical Procedures; Oral; Oral Leukoplakia; Oxidation-Reduction; Pharmaceutical Preparations; Phase I Clinical Trials; Plant Roots; Plants; Plasmid Cloning Vector; Plasmids; Premalignant; Property; Proteins; Protocols documentation; Radiation; Radiation Tolerance; Radiation therapy; Radiation-Sensitizing Agents; Reaction; Reporter; Resistance; Rhizome; Risk Factors; Role; Scheme; Second Primary Cancers; Selenocysteine; Signaling Protein; Smoke; Smoking; Subcutaneous Tissue; Superoxides; Survival Rate; TP53 gene; Testing; Therapeutic; Thioredoxin; Toxic effect; Transcription Factor AP-1; Transfection; Translating; Work; adduct; angiogenesis; bioactive food component; cancer cell; cell growth regulation; chemotherapy; cytotoxic; expression vector; gene cloning; head and neck cancer patient; in vivo; inhibitor/antagonist; keratinocyte; knock-down; malignant mouth neoplasm; mouse model; neoplastic cell; outcome forecast; overexpression; pre-clinical; public health relevance; radiation resistance; research study; response; selenoprotein; small hairpin RNA; thioredoxin reductase; thioredoxin reductase 1; tumor; tumor growth

DESCRIPTION (provided by applicant): Thioredoxin reductase 1 (TxRd1), is an essential selenoprotein with defined roles in redox regulation of cell growth, death (apoptosis), transcription, DNA repair, and angiogenesis. TxRd1 is overexpressed in many human cancers and these elevated levels of TxRd1 have been associated with poor prognosis due to enhanced cellular resistance to chemo- and radiation therapy. Chemical inhibitors of TxRd have yielded promising results in preclinical and clinical trials as cancer therapeutics and radiation sensitizers. Curcumin is a naturally occurring plant polyphenolic antioxidant with potent chemopreventive and antintumorigenic properties in preclinical animal models and a demonstrated low toxicity profile in Phase I clinical trials Recent data demonstrate a covalent interaction between curcumin and the conserved c-terminal cys-x-sec-cys motif in TxRd1. resulting in inhibition ofthe catalytic interaction between TxRd and thioredoxin. The electrons donated by NADPH are instead diverted to O2, to form superoxide and ultimately hydrogen peroxide. In this proposal we will investigate the role of TxRd1 as a critical mediator of the antitumorigeniceffects of curcumin alone and in combination with ionizing radiation in oraopharyngeal cancer cell lines, in vitro and in vivo. . Our preliminary data demonstrated > 50 fold higher level of TxRd1 in the human squamous carcinoma cell line FaDu compared to either an oral leukoplakia cell line MSK-Leuk1 or nontransformed keratinocytes. In specific aim 1, we plan to knockdown TxRd1 levels in FaDu cells using shRNA to the 3'UTR of the human TxRd1 gene cloned into the pSilencer expression vector. Conversely, TxRd1 will be overexpressed in MSK-leuk1 cells by transfection with the full length wild type TxRd1 gene, including the selenocysteine insertion element, from the 3'UTR. The stable clones selected above will be used to determine whether TxRd1 mediates the anti-proliferative and pro-apoptotic actions of curcumin, in vitro. In specific aim 2, we will use the stable clones selected above, to determine whether curcumin's efficacy as a radiation sensitizer also depends on inhibition of TxRd1. In specific aim 3, the TxRd1 knockdown and knock in cell lines, and the parental cell lines, will be grown as tumors in the cervical subcutaneous tissue of athymic nude mice. The efficacy of curcumin administered in the diet alone or in combination with ionizing radiation on orthotopic tumor growth and tumor cell death will be measured. Since curcumin is a natural bioactive food component with no overt systemic toxicities, promising results from these preclinical experiments can be readily translated into a chemoprevention schemes or combined chemo-radiation therapy protocol for treating head and neck cancers. PUBLIC HEALTH RELEVANCE: Head and neck cancers (HNC) are the sixth most common form of cancer worldwide, with over 500,000 new cases diagnosed annually. Although advances in surgery, and combined of radio and chemotherapies, have decreased morbidity, the survival rate at 5 years after initial prognosis remains at < 50%. Moreover, since smoking and alcohol use are the two most prevalent risk factors associated with HNSCC, field cancerization leads to second primary cancers in 20% of HNC patients. Cucumin, a natural product derived from the root of the plant Curcuma longa, has shown promise as a cancer chemopreventive, chemotherapeutic and radiation sensitizer, in preclinical and phase 1 clinical trials. The primary drawback to the use of curcumin is limited bioavailability due to low concentrations of the drug reaching the circulation. However, curcumin has been effective in tumors, such as colon and HNC, where direct access to the drug is possible. The primary aim of this study is to develop curcumin as a chemotherapeutic and radiation sensitizer for treating HNC..

描述（由申请人提供）：硫氧还蛋白还原酶1（TxRd 1）是一种必需的硒蛋白，在细胞生长、死亡（凋亡）、转录、DNA修复和血管生成的氧化还原调节中具有确定的作用。TxRd 1在许多人类癌症中过表达，这些TxRd 1水平升高与预后不良有关，这是由于细胞对化疗和放疗的抵抗力增强。TxRd的化学抑制剂作为癌症治疗剂和辐射增敏剂在临床前和临床试验中取得了有希望的结果。姜黄素是一种天然存在的植物多酚类抗氧化剂，在临床前动物模型中具有有效的化学预防和抗肿瘤特性，并且在I期临床试验中表现出低毒性。最近的数据表明，姜黄素与TxRd 1中保守的C-末端cys-x-sec-cys基序之间存在共价相互作用。从而抑制TxRd与硫氧还蛋白的催化作用。NADPH提供的电子被转移到O2，形成超氧化物，最终形成过氧化氢。在这个提议中，我们将研究TxRd 1作为姜黄素单独和与电离辐射联合在口咽癌细胞系中的抗肿瘤作用的关键介体的作用，在体外和体内。.我们的初步数据表明，与口腔白斑病细胞系MSK-Leuk 1或非转化的角质形成细胞相比，人鳞状细胞癌细胞系FaDu中TxRd 1的水平高出> 50倍。在具体目标1中，我们计划使用克隆到pSilencer表达载体中的人TxRd 1基因的3 'UTR的shRNA敲低FaDu细胞中的TxRd 1水平。相反，通过用全长野生型TxRd 1基因（包括来自3 'UTR的硒代半胱氨酸插入元件）转染，TxRd 1将在MSK-leuk 1细胞中过表达。以上选择的稳定克隆将用于确定TxRd 1是否在体外介导姜黄素的抗增殖和促凋亡作用。在具体目标2中，我们将使用以上选择的稳定克隆来确定姜黄素作为辐射敏化剂的功效是否也取决于TxRd 1的抑制。在具体目标3中，TxRd 1敲除和敲入细胞系以及亲代细胞系将在无胸腺裸小鼠的颈部皮下组织中作为肿瘤生长。将测量在饮食中单独施用或与电离辐射组合施用的姜黄素对原位肿瘤生长和肿瘤细胞死亡的功效。由于姜黄素是一种天然的生物活性食品成分，没有明显的全身毒性，这些临床前实验的有希望的结果可以很容易地转化为治疗头颈癌的化学预防方案或联合化疗-放疗方案。公共卫生相关性：头颈癌（HNC）是全球第六大常见癌症，每年诊断出超过50万例新病例。虽然手术的进步，以及放射和化学疗法的结合，降低了发病率，但初始预后后5年的生存率仍低于50%。此外，由于吸烟和饮酒是与HNSCC相关的两个最普遍的风险因素，因此现场癌变导致20%的HNC患者发生第二原发性癌症。黄瓜素是一种来源于植物姜黄根的天然产物，在临床前和1期临床试验中显示出作为癌症化学预防剂、化学治疗剂和辐射增敏剂的前景。使用姜黄素的主要缺点是由于到达循环的药物浓度低而导致生物利用度有限。然而，姜黄素在肿瘤中是有效的，如结肠和HNC，在那里直接获得药物是可能的。本研究的主要目的是开发姜黄素作为治疗HNC的化疗和放射增敏剂。