HIV integration-mediated modulation of immune regulation in HPV-associated cancers

 描述(申请人提供)：可归因于人类乳头瘤病毒(HPV)感染的癌症是世界上最常见的与艾滋病毒相关的恶性肿瘤；特别是撒哈拉以南非洲的宫颈癌和美国长期幸存者的肛门癌。造成这些几率增加的机制还没有完全弄清楚。与其他与艾滋病毒相关的恶性肿瘤不同，宫颈癌的发病率并不完全与CD4 T细胞计数最低点的深度有关，这表明除了CD4不足外，还有一种机制使艾滋病毒感染者容易患上宫颈癌和其他与HPV相关的癌症。我们的团队和其他人做了一个重要的观察，即HIV整合到某些基因中似乎可以调节宿主基因的表达，从而有利于受感染T细胞的增殖和持久性。新出现的数据显示，HIV整合可以扭曲幼稚的CD4T细胞向T调节细胞的分化，为持续HIV感染的免疫病理学提供了进一步的机械性见解。上述观察结合T调节细胞在宫颈癌中的公认作用，导致了我们的总体假设，即HIV整合到调节T调节细胞的宿主基因中，通过基于肿瘤的免疫改变，对于HIV感染者的宫颈癌的发展是不可或缺的。为了评估这一假设，我们将利用与乌干达癌症研究所建立的良好合作关系来定义HPV感染的宫颈组织中与T调节细胞功能相关的基因中的HIV整合。我们将招募感染艾滋病毒和未感染的乌干达妇女进行宫颈癌筛查阳性测试(冰醋酸目视检查)，并确定那些感染HPV的高危人群进行研究。在第一个目标中，我们将比较HIV整合位点、T调节细胞密度和HIV前病毒在宫颈组织中的表达，以及高危HPV感染自发清除的HIV感染妇女的宫颈组织中检查点分子的表达。此外，T调节细胞和细胞毒性T细胞的蛋白质组通路将在HIV感染的进展为宫颈肿瘤的妇女和未感染HPV的高危HPV妇女之间进行比较，后者可能清除HPV。在第二个目标中，我们将评估CD4T细胞克隆在前病毒浸润性宫颈不典型增生中的宿主基因功能。具体地说，我们将使用在外周血液中检测到的克隆细胞来表征这些细胞克隆的T细胞标记。来自宫颈不典型增生克隆的HIV感染循环CD4T细胞将从单个HIV感染细胞的微型培养中扩增，使用一种新技术来全面表征HIV前病毒和周围宿主基因组。最后，将评估通过将HIV LTR启动子插入到在宫颈癌病例中被破坏的基因组位置来重述原始的CD4T细胞的转录组和表型变化的能力。这些数据将告诉我们，艾滋病毒整合到宿主基因是否以及如何易于增加HPV相关癌症的风险，并指出治疗持续性HPV感染的新干预措施。

 DESCRIPTION (provided by applicant): Cancers attributable to human papillomavirus (HPV) infections are the most common HIV-associated malignancies around the world; specifically cervical cancer in sub-Saharan Africa and anal cancer among long- term survivors in the United States. The mechanisms responsible for these increased odds are not completely understood. In contrast to other HIV-associated malignancies, the incidence of cervical cancer is not entirely related to the depth of CD4+ T-cell count nadir, suggesting that a mechanism in addition to inadequate CD4+ "help" predisposes HIV-infected individuals to cervical and other HPV-associated cancers. Our group and others made the important observation that HIV integration into certain genes appears to modulate host gene expression to favor proliferation and persistence of infected T-cells. Emerging data show that HIV integration can skew the differentiation of naïve CD4+ T-cells into T regulatory cells, providing further mechanistic insights to the immunopathology of persistent HIV infection. The aforementioned observations combined with the recognized role of T regulatory cells in cervical cancer led to our overarching hypothesis that HIV integration into host genes that modulate T regulatory cells are integral to the development of cervical cancer in HIV- infected individuals through alterations of tumor-based immunity. To evaluate this hypothesis, we will utilize a well established collaboration with the Uganda Cancer Institute to define HIV integration into genes associated with T regulatory cell function in HPV-infected cervical tissues. We will enroll HIV-infected and -uninfected Ugandan women with a positive cervical cancer screening test (visual inspection with acetic acid), and identify those with high-risk HPV infections for study. In the first Aim, we will compar HIV integration sites, density of T regulatory cells with HIV proviruses and expression of checkpoint molecules in the cervical tissue of women who have progressed to pre-cancer/carcinoma with HIV-infected women with spontaneous clearance of high- risk HPV infections. Furthermore, the proteome pathways of T regulatory cells and cytotoxic T cells will be compared between HIV-infected women with progression to cervical neoplasia with -uninfected women with high-risk HPV who are likely to clear their HPV. In the second Aim, we will evaluate host gene function of CD4+ T-cells clones with proviruses infiltrating the cervical dysplasia. Specifically, we will characterize the T-cell markers of these cell clones using cells from the clone detected in the peripheral blood. HIV-infected circulating CD4+ T-cells from the clones infiltrating the cervical dysplasia will be expanded from in mini-cultures of single HIV infected cells using a novel technology to comprehensively characterize the HIV provirus and surrounding host genome. Finally, the ability to recapitulate transcriptome and phenotypic changes in naïve CD4+ T-cells by insertion of the HIV LTR promoter into genomic sites found to be disrupted in cervical cancer cases will be evaluated. Together these data will inform whether and how HIV integration into host genes predisposes to an increased risk of HPV-associated cancers, and point to novel interventions to treat persistent HPV infections.