Phage Display for Improved Peptide-based Tumor Targeting and Imaging Agents

用于改进基于肽的肿瘤靶向和成像剂的噬菌体展示

• 批准号: 8263685
• 负责人: SUSAN L DEUTSCHER
• 金额: --
• 依托单位: HARRY S. TRUMAN MEMORIAL VA HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-01 至 2014-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8263685
• 关键词: Accounting; Address; Adverse effects; Affinity; Antibodies; Antigen Targeting; Antigens; Bacteriophages; Binding; Breast; Breast Carcinoma; Cancer Detection; Cancer Diagnostics; Carbohydrates; Carcinoma; Cause of Death; Cell-Cell Adhesion; Characteristics; Clinic; Clinical; Cysteine; Detection; Development; Diagnostic; Diagnostic Imaging; Disease; Disseminated Malignant Neoplasm; Drug Kinetics; Emission-Computed Tomography; Engineering; Excretory function; Female; Foundations; Future; Galectin 3; Gender; Goals; Health; Health Services Research; Healthcare; Human; Image; In Vitro; Kidney; Label; Lead; Libraries; Ligands; Malignant Neoplasms; Malignant neoplasm of ovary; Malignant neoplasm of prostate; Mammary Neoplasms; Medical; Methods; Military Personnel; Mission; Modality; Modeling; Molecular Biology; Molecular Probes; Molecular Weight; Mus; Neoplasm Metastasis; Ovarian Carcinoma; Ovary; Patients; Peptides; Phage Display; Population; Positron; Prostate; Prostate carcinoma; Prostatic Neoplasms; Protein Engineering; Radiochemistry; Radioimmunoconjugate; Radiolabeled; Radiopharmaceuticals; Research; Screening procedure; Signal Pathway; Signal Transduction; Specificity; Staging; Structure; Testing; Therapeutic; Thompson-Friedenreich Antigen; Translating; Translations; Treatment Efficacy; Tumor Antigens; United States; United States Department of Veterans Affairs; Veterans; Woman; Work; base; cancer cell; cancer diagnosis; cancer imaging; cancer therapy; erbB-2 Receptor; improved; in vivo; innovation; male; malignant breast neoplasm; meetings; novel; novel strategies; optical imaging; ovarian neoplasm; overexpression; polypeptide; public health relevance; radiotracer; response; scaffold; single photon emission computed tomography; tumor; tumor growth; tumor specificity; tumorigenesis; uptake

DESCRIPTION (provided by applicant): Cancer is the second leading cause of death in the United States and US Veterans. Over 28% of cancer diagnoses in US Veterans in 2009 were for prostate, breast, and ovarian carcinoma. However, these cancers are often asymptomatic in beginning stages of the disease. Prostate cancer is a major health problem in male Veterans and it has been estimated that over 25% already have prostate cancer. Gender-associated breast and ovarian cancers are also of concern, especially since one out of every 15 Veterans is female. A VA Center for Women has been established in order to better address the rising medical needs of our female Veterans. While screening and detection methods exist for these cancers, they all have limitations. It can be envisioned that the use of molecules that specifically target antigens on carcinomas and metastases will lead to improved cancer detection and treatment modalities. Radiolabeled antibodies and peptides are currently being explored as diagnostic cancer imaging agents. However, high molecular weight antibodies as well as small peptides may not be ideal as cancer imaging agents in vivo. Only a small number of radiolabeled antibodies and peptides possess the requisite high affinity, specificity, stability, and tumor uptake to serve as cancer imaging agents. Thus, finding new cancer targeting vehicles and cancer-associated antigens is a central goal of the field. Development of specific tumor-targeting molecules that can be used safely and non- invasively to detect and treat cancer is undeniably an important priority for the Veterans Administration if it is to meet the health care challenges of our past, current, and future military personnel. New peptide-based molecular probes to facilitate cancer imaging are rapidly evolving due to implementation of bacteriophage (phage) display approaches. While radiolabeled peptides have shown good tumor-targeting propensity in vitro, their translation into the clinic has been slowed by sub-optimal tumor retention and almost universal high renal uptake and retention. We have used phage display to obtain peptides that target the tumor-associated ErbB-2 receptor, galectin-3 (gal-3) and its carbohydrate ligand Thomsen- Friedenreich (TF) antigen, which are involved in cancer cell adhesion and signaling. We hypothesize that peptides that bind ErbB-2, gal-3, and TF grafted into constrained loops of polypeptide scaffolds once radiolabeled, will form the foundation for novel single photon emission computed tomography (SPECT) and positron emission computed tomography (PET) imaging agents for prostate, breast, and ovarian tumors. We will expand the applications of phage display to employ innovative functional selection approaches in vivo to improve the imaging and, potentially, therapeutic efficacy of the tumor-targeting radiolabeled peptides. The radiolabeled conjugates may serve as diagnostic radiopharmaceuticals for the detection of primary and metastatic cancer and indicators of response to therapy. In the long term, the peptides may function in vivo to reduce tumor growth and metastasis by blocking signaling pathways involved in tumorigenesis. Diverse molecular biology, protein engineering, radiochemistry, and optical imaging approaches will be employed. The objectives of this proposed research are to: 1) select phage display libraries based on the ErbB-2 and gal-3-targeting sequences in mice in order to identify phage and corresponding peptides with high tumor uptake and low kidney retention; 2) engineer the optimized peptide motifs into stable small molecular weight cysteine-constrained scaffolds for enhanced in vivo stability, affinity, and rapid excretion; 3) compare the in vivo SPECT imaging efficacy of 111Indium-radiolabeled ErbB-2-, gal-3-, and TF- targeting linear peptides and engineered peptide scaffolds in at least one appropriate tumor model (i.e. breast, prostate or ovary); and 4) develop 64Copper-labeled peptide counterparts for sensitive PET imaging. This work is significant and relevant to the VA mission because the peptides discovered here may translate into novel prostate, breast, and ovarian cancer diagnostics and therapeutics for our veterans. PUBLIC HEALTH RELEVANCE: Prostate cancer is one of the most frequently diagnosed cancers among United States Veteran males. Of recent concern to the VA are female-related cancers including breast and ovarian cancer. Research and health care related to female cancers is now a VA priority due to the almost 10% female Veteran population. These cancers are treatable if detected early, before metastasis occurs. Unfortunately, standard screening tests are either not specific, difficult to administer, or expensive. Thus, facile and more specific means to detect these, cancers are needed. Our research is relevant to the Veterans Administration Mission in that we are developing innovative tumor-targeting agents based on peptide scaffolds for early radioimaging detection of prostate, breast, and ovarian cancer. The agents will target the tumor-associated antigens, ErbB-2 and galectin- 3/Thomsen-Friedenreich that are overexpressed on these cancers. Being specifically targeted to molecules on cancer cells, the radioimaging agents will be well tolerated in patients and not fraught with harmful side effects.

描述（由申请人提供）： 癌症是美国和美国退伍军人的第二大死因。 2009 年，美国退伍军人中超过 28% 的癌症诊断为前列腺癌、乳腺癌和卵巢癌。然而，这些癌症在疾病的早期阶段通常是无症状的。前列腺癌是男性退伍军人的一个主要健康问题，据估计超过 25% 的人已经患有前列腺癌。与性别相关的乳腺癌和卵巢癌也令人担忧，特别是因为每 15 名退伍军人中就有 1 人是女性。为了更好地满足女性退伍军人日益增长的医疗需求，建立了退伍军人管理局妇女中心。虽然存在针对这些癌症的筛查和检测方法，但它们都有局限性。可以预见，使用专门针对癌症和转移瘤抗原的分子将改善癌症检测和治疗方式。目前正在探索放射性标记的抗体和肽作为诊断癌症成像剂。然而，高分子量抗体以及小肽可能不是理想的体内癌症成像剂。只有少数放射性标记的抗体和肽具有用作癌症成像剂所需的高亲和力、特异性、稳定性和肿瘤摄取。因此，寻找新的癌症靶向载体和癌症相关抗原是该领域的中心目标。如果要应对我们过去、现在和未来军事人员的医疗保健挑战，开发可安全、非侵入性地检测和治疗癌症的特定肿瘤靶向分子无疑是退伍军人管理局的一个重要优先事项。 由于噬菌体（噬菌体）展示方法的实施，促进癌症成像的新型基于肽的分子探针正在迅速发展。虽然放射性标记的肽在体外显示出良好的肿瘤靶向倾向，但由于肿瘤保留效果不佳以及几乎普遍存在的高肾脏摄取和保留，它们向临床的转化已经放缓。我们使用噬菌体展示来获得靶向肿瘤相关 ErbB-2 受体、半乳糖凝集素-3 (gal-3) 及其碳水化合物配体 Thomsen-Friedenreich (TF) 抗原的肽，这些抗原参与癌细胞粘附和信号传导。我们假设，结合 ErbB-2、gal-3 和 TF 的肽一旦被放射性标记，被移植到多肽支架的约束环中，将为用于前列腺、乳腺癌和卵巢肿瘤的新型单光子发射计算机断层扫描 (SPECT) 和正电子发射计算机断层扫描 (PET) 成像剂奠定基础。我们将扩大噬菌体展示的应用，以在体内采用创新的功能选择方法，以改善肿瘤靶向放射性标记肽的成像和潜在的治疗功效。放射性标记的缀合物可以用作诊断放射性药物，用于检测原发性和转移性癌症以及治疗反应的指标。从长远来看，这些肽可能在体内发挥作用，通过阻断与肿瘤发生有关的信号通路来减少肿瘤的生长和转移。 将采用多种分子生物学、蛋白质工程、放射化学和光学成像方法。本研究的目的是： 1) 基于小鼠 ErbB-2 和 gal-3 靶向序列选择噬菌体展示文库，以鉴定具有高肿瘤摄取和低肾保留的噬菌体和相应肽； 2) 将优化的肽基序设计成稳定的小分子量半胱氨酸限制支架，以增强体内稳定性、亲和力和快速排泄； 3) 比较111Indium放射性标记的ErbB-2-、gal-3-和TF-靶向线性肽和工程肽支架在至少一种合适的肿瘤模型（即乳腺、前列腺或卵巢）中的体内SPECT成像功效； 4) 开发用于敏感 PET 成像的 64 铜标记肽对应物。这项工作意义重大，并且与退伍军人事务部的使命相关，因为这里发现的肽可能会转化为我们退伍军人的新型前列腺癌、乳腺癌和卵巢癌诊断和治疗方法。 公共卫生相关性： 前列腺癌是美国退伍男性中最常诊断出的癌症之一。 VA 最近关注的是与女性相关的癌症，包括乳腺癌和卵巢癌。由于女性退伍军人人口占近 10%，因此与女性癌症相关的研究和医疗保健现已成为 VA 的优先事项。如果在转移发生之前及早发现，这些癌症是可以治疗的。不幸的是，标准筛查测试要么不具体，要么难以管理，要么昂贵。因此，需要简便且更具体的方法来检测这些癌症。我们的研究与退伍军人管理局使命相关，因为我们正在开发基于肽支架的创新肿瘤靶向剂，用于前列腺癌、乳腺癌和卵巢癌的早期放射成像检测。这些药物将针对在这些癌症中过度表达的肿瘤相关抗原 ErbB-2 和半乳糖凝集素 3/Thomsen-Friedenreich。由于专门针对癌细胞上的分子，放射成像剂对患者具有良好的耐受性，并且不会产生有害的副作用。