Osteoclasts and bone cancer

破骨细胞和骨癌

• 批准号: 8088210
• 负责人: DENIS R CLOHISY
• 金额: $ 28.99万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-08-03 至 2014-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8088210
• 关键词: Address; Adopted; Affect; Bone Diseases; Bone neoplasms; Bystander Effect; Cancer Patient; Caring; Cell Death; Cell Lineage; Clinical Trials; Cytosine deaminase; Development; Disease; Effectiveness; Ensure; Enzymes; Exposure to; Figs - dietary; Fluorouracil; Funding; Future; Gene Delivery; Gene Expression; Gene Expression Regulation; Genes; Health; Human; Hypoxia; In Vitro; Injection of therapeutic agent; Investigational Therapies; Knowledge; Lentivirus Vector; Malignant Bone Neoplasm; Malignant Neoplasms; Mediating; Methods; Modeling; Modification; Molecular; Oncogenes; Osteoclasts; Pathologic; Patients; Plant Roots; Population; Prodrugs; Radiation; Radiation therapy; Regulator Genes; Regulatory Element; Research; Safety; Scheme; Science; Site; Solutions; Specificity; Stem cells; Subfamily lentivirinae; System; Testing; Therapeutic; Toxic effect; Transcript; Translations; United States; Work; animal model development; base; bisphosphonate; bone; cancer cell; cancer therapy; cell type; design; falls; gene delivery system; human disease; improved; in vitro testing; in vivo; innovation; killings; neoplastic cell; novel; novel therapeutics; precursor cell; promoter; response; tartrate-resistant acid phosphatase; therapeutic gene; therapy design; treatment strategy; tumor; tumor growth; vector

DESCRIPTION (provided by applicant): The long term objective of our research is to improve the treatment of bone cancer through development of animal models resembling human disease and through testing new experimental therapies in these models. This competitive renewal application builds on exciting progress made during the previous funding period. That progress demonstrated several critical points: 1) osteoclast lineage cells can be used as an effective gene delivery system to sites of bone cancer; 2) osteoclast precursor cells serve as the ideal gene delivery system, in that the Good Samaritan effect is not present, permitting the gene delivery vehicle (osteoclast precursor) to survive the therapy and therefore provide extended expression of the therapeutic molecule cytosine deaminase. Our Preliminary Studies now show that lentiviral approach for gene delivery is operational in our hands and is very promising as a vector for providing the therapeutic gene to sites of tumor. The current proposal adopts modifications of the osteoclast-directed treatment scheme that was studied during the previous funding period. These adaptations will advance our work toward a clinical trial in patients. The proposed modifications will increase the specificity of the therapy, will permit regulation of gene expression, and will decrease the toxicity of current treatment. These modifications include use of a new therapeutic vector (lentivirus base) and adaptation of the osteoclast delivery to the method of direct intratumoral injection. The feasibility of the approach and the experimental methods and design are greatly enhanced in this A2 submission, as all concerns raised by the reviewers have been addressed. Specifically, we have demonstrated effective therapeutic gene transduction into osteoclast precursor cells using a lentiviral approach. We have demonstrated that hypoxia induces HRE activation in purified populations of osteoclast lineage cells in vitro, and we have demonstrated that bisphosphonate therapy does not interfere with the survival of intratumoral-injected osteoclast progenitor cells. The aims of this application mirror those previously proposed, but are more strongly supported by our response to the review. Aim 1 will determine if hypoxia and radiation- activated promoters can mediate osteoclast-directed killing of bone cancer cells in vitro. In this aim, osteoclast progenitor cells will be transduced with lentivirus containing our molecular switch vector which is responsive to hypoxia and radiation, and which drives expression of the enzyme cytosine deaminase. The cytosine deaminase prodrug enzyme system will then be tested in vitro. Aim 2 will determine if Tg osteoclast precursor cells expressing the prodrug enzyme cytosine deaminase can kill bone cancer in vivo, and will determine if authentic osteoclast precursor cells transduced with the lentivirus molecular switch cytosine deaminase vector can kill bone cancer in vivo. Successful completion of this aim will serve as a next step toward experimentation in humans. Aim 3 will determine if the 5' portion of the TRAP gene regulates expression of the TRAP 1C transcript. This aim is critically important, as it will help direct future design of osteoclast-specific gene delivery vectors, ensuring cell-type-specific expression and maximizing safety. PUBLIC HEALTH RELEVANCE: This project is important because it proposes to develop a new treatment for bone cancer. Bone cancer affects a half-million people per year in the United States and currently is not curable. The strategy pursued in this application will combine current treatments such as radiation therapy, with new and emerging treatments to increase our ability to kill bone cancer.

描述（由申请人提供）：我们研究的长期目标是通过开发类似人类疾病的动物模型并通过测试这些模型中的新实验疗法来改善骨癌的治疗。这项竞争性更新申请基于上一个资金期间的激动人心的进步。该进展证明了几个关键点：1）破骨细胞细胞可以用作骨癌部位的有效基因输送系统； 2）破骨细胞前体细胞充当理想的基因递送系统，因为不存在良好的samaritan效应，因此允许基因递送​​载体（破骨细胞前体）在治疗中生存，因此提供了治疗性分子胞质氨基氨酸酶的扩展表达。现在，我们的初步研究表明，基因输送的慢病毒方法在我们手中运作，作为向量提供治疗基因为肿瘤部位的载体非常有前途。当前的提案采用了在上一个资金期间研究的破骨细胞指导的治疗方案的修改。这些适应将使我们的工作朝着患者的临床试验前进。提出的修饰将提高治疗的特异性，允许调节基因表达，并降低当前治疗的毒性。这些修饰包括使用新的治疗载体（慢病毒碱）以及将破骨细胞递送到直接肿瘤内注射方法。在此A2提交中，该方法和实验方法和设计的可行性大大提高了，因为审阅者提出的所有担忧均已解决。具体而言，我们使用慢病毒方法证明了有效的治疗基因转导向破骨细胞细胞。我们已经证明了缺氧在体外诱导纯化的骨细胞谱系细胞纯化群体中的HRE激活，并且我们已经证明双膦酸盐治疗不会干扰注入肿瘤内注射的破骨细胞祖细胞的存活。该应用程序的目的反映了先前提出的那些，但我们对审查的回应更加支持。 AIM 1将确定缺氧和辐射激活的启动子是否可以在体外介导骨癌细胞的破骨细胞杀死。在此目标中，将破骨细胞祖细胞用含有我们的分子开关载体的慢病毒载体转导，该分子开关载体对缺氧和辐射有反应，并驱动酶胞嘧啶脱氨酶的表达。然后，将在体外测试胞嘧啶脱氨酶前药系统。 AIM 2将确定表达原始酶胞嘧啶脱氨酶的TG破骨细胞前体细胞是否可以在体内杀死骨癌，并将确定是否用慢气病毒分子开关胞氨酸开关替代链氨基脱氨酶载体可以杀死Vivo中的骨癌。成功完成此目标将是对人类实验的下一步。 AIM 3将确定陷阱基因的5'部分是否调节陷阱1C转录物的表达。这个目标至关重要，因为它将有助于指导破骨细胞特异性基因递送向量的未来设计，从而确保细胞类型特异性的表达并最大程度地提高安全性。 公共卫生相关性：该项目很重要，因为它建议开发新的骨癌治疗方法。骨癌在美国每年影响50万人，目前无法治愈。在本应用中采取的策略将结合当前治疗方法，例如放射治疗，以及新的和新兴的治疗方法，以提高我们杀死骨癌的能力。