Protein Biomarkers for a New Human Polyomavirus in AIDS-related Malignancies

艾滋病相关恶性肿瘤中新型人类多瘤病毒的蛋白质生物标志物

• 批准号: 7691836
• 负责人: PATRICK S. MOORE
• 金额: $ 34.09万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-25 至 2011-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7691836
• 关键词: AIDS related cancer; Acquired Immunodeficiency Syndrome; Antibodies; Antibody Formation; Antigens; Baculoviruses; Biological Assay; Biological Markers; Blood; Blood Tests; Carcinoma; Cell Line; Cells; Cercopithecus pygerythrus; Clinical; Common Neoplasm; Diagnostic tests; Early Diagnosis; Elderly; Ensure; Enzyme-Linked Immunosorbent Assay; Epitope Mapping; Etiology; Funding; Gene Expression Profile; Generations; Genome; Human; Human Virus; Immune; Immunocompromised Host; Immunological Diagnosis; Infection; Laboratories; Malignant Epithelial Cell; Malignant Neoplasms; Mammalian Cell; Measures; Merkel cell carcinoma; Methods; Monoclonal Antibodies; Mutate; Oncogenic Viruses; Patients; Pattern; Peptide Library; Peptide Mapping; Persons; Pharmaceutical Preparations; Polyomavirus; Polyomavirus Infections; Population; Preventive; Proteins; Reagent; Research Personnel; Role; Screening procedure; Serum; Skin Cancer; Southern Blotting; Specificity; Staining method; Stains; Techniques; Time; Tissue Microarray; Tissues; Transplantation; Vaccines; Viral; Viral Antigens; Viral Genome; Viral Proteins; Viral Tumor Antigens; Virus; Virus-like particle; Viviparous-1 protein; advanced disease; base; cross reactivity; digital; immunosuppressed; mortality; neoplastic cell; novel; patient population; sialosyl-T antigen; tumor

DESCRIPTION (provided by applicant): Merkel cell carcinoma (MCC) is a neuroectodermal, AIDS-related cancer suspected to have a viral etiology. MCC is 13 times more common than expected among AIDS patients and occurs in post-transplant and other immunosuppressed patient populations. While rare, it is the most aggressive skin cancer and only 50% of patients with advanced disease survive 9 months or longer. There are no early detection markers and it is frequently misdiagnosed with other small round cell tumors. We identified a novel polyomavirus in MCC using digital transcriptome subtraction (DTS). This agent, Merkel carcinoma polyomavirus (MCPyV), is most closely related to African green monkey lymphotropic polyomavirus (LPyV). Between 15-30% of persons have antibodies to LPyV, which has led investigators to speculate on the existence of a closely related but undiscovered human virus. MCPyV has a 5387 bp genome and expresses T antigen proteins in MCC tumors. Most MCC are positive for an integrated MCPyV that is readily detected by PCR and by Southern blotting. In contrast only 8-16% of control tissues harbor detectable viral genome. On Southern blotting, the majority of MCPyV positive tumors show a monoclonal somatic insertion pattern suggesting that the virus contributes to clonal cell expansion. We have developed reagents required to study this new virus including infected cell lines, specific antibodies and an overlapping peptide library for the VP1 protein. Preliminary studies suggest that MCPyV is a common but not ubiquitous infection that contributes to MCC when the virus mutates and integrates into the host genome. Identification of specific biomarkers for MCPyV infection is essential to determine MCPyV's role in human cancers. We propose to develop screening blood tests for MCPyV infection using established polyomavirus immunodiagnostic techniques as well as new immunodiagnostic methods. We will identify and characterize human antibody responses to MCPyV infection using cell-based IFA, MCPyV peptide mapping and virus-like particle ELISA with sera from well-defined populations. These assays will be vetted for cross-reactivity to known human polyomaviruses to ensure assay specificity. We also propose generating specific monoclonal antibodies to be used to detect viral antigens in tissue microarrays so that common tumors can be screened for infection. Expression of viral proteins can also be correlated with cellular protein biomarker expression to determine clinical course and responsiveness to treatment. This is the first proposal for funding to study a new human tumor virus found in our laboratory, MCPyV, likely to cause Merkel cell carcinoma. Merkel cell carcinoma is a cancer of the elderly, AIDS, transplant and other immunosuppressed persons. It has the highest overall mortality rate among skin cancers and there are no specific preventive measures or diagnostic tests for MCPyV infection. If funded, this proposal will develop accurate blood assays to measure antibody proteins marking MCPyV infection and to measure viral proteins in tissues. These are required to understand human infection with this virus and to develop effective vaccines and drugs against MCPyV.

描述（由申请人提供）：默克尔细胞癌（MCC）是一种神经外胚层、与艾滋病相关的癌症，疑似具有病毒病因。 MCC 在 AIDS 患者中的发生率比预期高 13 倍，并且发生在移植后和其他免疫抑制的患者群体中。虽然罕见，但它是最具侵袭性的皮肤癌，只有 50% 的晚期疾病患者能存活 9 个月或更长时间。没有早期检测标志物，经常被误诊为其他小圆细胞肿瘤。我们使用数字转录组消减 (DTS) 在 MCC 中鉴定出一种新型多瘤病毒。这种病原体是默克尔癌多瘤病毒 (MCPyV)，与非洲绿猴嗜淋巴细胞多瘤病毒 (LPyV) 关系最密切。 15-30% 的人具有 LPyV 抗体，这促使研究人员推测是否存在一种密切相关但尚未发现的人类病毒。 MCPyV 具有 5387 bp 基因组，在 MCC 肿瘤中表达 T 抗原蛋白。大多数 MCC 的整合 MCPyV 呈阳性，可通过 PCR 和 Southern 印迹轻松检测到。相比之下，只有 8-16% 的对照组织含有可检测到的病毒基因组。在 Southern 印迹中，大多数 MCPyV 阳性肿瘤显示单克隆体细胞插入模式，表明该病毒有助于克隆细胞扩增。我们开发了研究这种新病毒所需的试剂，包括受感染的细胞系、特异性抗体和 VP1 蛋白的重叠肽库。初步研究表明，MCPyV 是一种常见但并非普遍存在的感染，当病毒突变并整合到宿主基因组中时，会导致 MCC。鉴定 MCPyV 感染的特异性生物标志物对于确定 MCPyV 在人类癌症中的作用至关重要。我们建议使用已建立的多瘤病毒免疫诊断技术以及新的免疫诊断方法开发针对 MCPyV 感染的筛查血液检测。我们将使用基于细胞的 IFA、MCPyV 肽图谱和病毒样颗粒 ELISA，以及来自明确人群的血清来识别和表征人类抗体对 MCPyV 感染的反应。这些测定将经过与已知人类多瘤病毒的交叉反应性审查，以确保测定的特异性。我们还建议生成特异性单克隆抗体，用于检测组织微阵列中的病毒抗原，以便筛查常见肿瘤的感染情况。病毒蛋白的表达还可以与细胞蛋白生物标志物表达相关，以确定临床病程和对治疗的反应。这是第一个资助研究我们实验室发现的新型人类肿瘤病毒 MCPyV 的提案，该病毒可能导致默克尔细胞癌。默克尔细胞癌是老年人、艾滋病患者、移植者和其他免疫抑制者的癌症。它是皮肤癌中总体死亡率最高的，并且没有针对 MCPyV 感染的具体预防措施或诊断测试。如果获得资助，该提案将开发准确的血液检测方法，以测量标记 MCPyV 感染的抗体蛋白，并测量组织中的病毒蛋白。这些是了解人类感染这种病毒并开发有效的针对 MCPyV 的疫苗和药物所必需的。