Dissecting the Kaposi Sarcoma Tumor Microenvironment at the Single Cell Level

项目摘要/摘要 卡波西肉瘤(KS)是世界上最常见的与艾滋病毒相关的恶性肿瘤之一，也是一种主要的 撒哈拉以南非洲(SSA)癌症发病率和死亡率的原因。尽管KS可以发生在未感染艾滋病毒的人中 个人，特别是被SSA称为“地方性”KS-HIV感染的人，会增加数千名KS的风险- 收牌。KS是一种独特的肿瘤，其发病机制与HHV-8慢性感染、血管生成障碍、 和炎症。越来越多的证据表明，这些不同组件之间相互作用的重要性 肿瘤微环境(TME)在推动肿瘤发生和治疗反应中的作用 恶性肿瘤。然而，我们对KS TME的组成和功能的了解是有限的。详细 对KS TME的体内研究将有助于阐明KS的发病机制，包括HIV的独特作用 感染，可以阐明肿瘤生物学的基本方面，并帮助确定新的治疗方法。 自2011年以来，我们的团队一直在对KS进行一项全面的前瞻性队列研究 HIV+和HIV-成人在乌干达坎帕拉的乌干达癌症研究所开始治疗。登记的科目 在这项研究上提供血液样本和连续的肿瘤活检，并严格跟踪长达1年的时间 定义治疗反应和临床结果。到目前为止，我们的结果是基于对160多名KS受试者的研究， 提示乌干达HIV+和HIV-KS受试者的临床结果可能存在的差异，并提供了 关于乌干达KS病毒学和免疫学的挑衅性初步数据。我们的团队最近开发了 并实施了一项从KS肿瘤中分离出可存活的单个细胞的方案-包括两种肿瘤细胞， 肿瘤浸润性淋巴细胞(TIL)和巨噬细胞--这为我们提供了扩大研究的独特机会 艾滋病毒在KS的发展和进展到单细胞水平上的作用。在本申请中，我们建议 通过对分离的单个细胞进行全面的分子图谱分析，确定HIV在KS肿瘤生态位中的作用 来自20例HIV+和20例HIV-成人的连续获得的KS肿瘤的肿瘤细胞、TIL和巨噬细胞。这个 具体目标是： 1)比较HIV+和HIV-的KS肿瘤细胞的转录水平。 2)对来自HIV+和HIV-成人的KS肿瘤中的免疫细胞进行连续转录图谱，并 确定它们转录谱的变化是否与抑制HIV和治疗相关 回应。 3)确定候选CD8+“公共”HHV-8特异性浸润性T细胞在KS肿瘤中的抗原特异性。 与更好的治疗反应相关。 这些研究的结果将对HIV在KS发病机制中的作用提供前所未有的见解 为KS的抗原特异性免疫治疗奠定基础。

PROJECT SUMMARY / ABSTRACT Kaposi sarcoma (KS) is among the most common of HIV-associated malignancies worldwide, and a leading cause of cancer morbidity and mortality in sub-Saharan Africa (SSA). Although KS can occur in HIV-uninfected individuals, particularly in SSA – termed “endemic” KS – HIV infection increases the risk of KS several thousand- fold. KS is a unique tumor whose pathogenesis involves chronic infection with HHV-8, disordered angiogenesis, and inflammation. Increasing evidence points to the importance of the interaction of these various components of the tumor microenviroment (TME) in driving tumorigenesis and response to treatment in a range of malignancies. However, our understanding of the composition and function of the KS TME is limited. Detailed study of the KS TME in vivo will elucidate mechanisms of KS pathogenesis, including the unique role of HIV infection, could elucidate fundamental aspects of tumor biology and help identify new therapeutic approaches. Since 2011 our team has been conducting a comprehensive prospective cohort study (“HIPPOS”) of KS in HIV+ and HIV- adults initiating treatment at the Uganda Cancer Institute in Kampala, Uganda. Subjects enrolled on this study provide blood samples and serial tumor biopsies and are followed for up to 1 year to rigorously define treatment response and clinical outcomes. Our results to date, based on study of over 160 KS subjects, suggest possible differences in the clinical outcome of HIV+ and HIV- KS subjects in Uganda, and have provided provocative preliminary data on the virology and immunology of KS in Uganda. Our team has recently developed and implemented a protocol for the isolation of viable single cells from KS tumors – including both tumor cells, tumor-infiltrating lymphocytes (TIL), and macrophages – that offers the unique opportunity to extend our studies of the role of HIV in the development and progression of KS to the single-cell level. In this application we propose to define the role of HIV in the KS tumor niche by performing comprehensive molecular profiling of isolated single tumor cells, TIL, and macrophages from serially acquired KS tumors from 20 HIV+ and 20 HIV- adults. The specific aims are: 1) To compare the transcriptional profile of KS tumor cells from HIV+ and HIV- subjects. 2) To perform serial transcriptional profiling of immune cells in KS tumors from HIV+ and HIV- adults, and to determine if changes in their transcriptional profiles are correlated with suppression of HIV and with treatment response. 3) To define the antigenic specificity of candidate CD8+ “public” HHV-8-specific infiltrating T cells in KS tumors that are associated with superior treatment response. The results of these studies will provide unprecedented insights into the role of HIV in the pathogenesis of KS and its response to treatment and could lay a foundation for antigen-specific immunotherapy of KS.