Mechanisms of KSHV-induced endothelial cell loss of contact inhibition of proliferation

KSHV诱导内皮细胞失去接触抑制增殖的机制

• 批准号: 10762813
• 负责人: Eva Henriette Gottwein
• 金额: $ 49.45万
• 依托单位: NORTHWESTERN UNIVERSITY AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-07-01 至 2028-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10762813
• 关键词: AIDS related cancer; Acquired Immunodeficiency Syndrome; Actins; Address; Adherens Junction; Adhesions; Automobile Driving; Binding; Blood Vessels; Cell Culture Techniques; Cell Cycle; Cell Cycle Arrest; Cell Proliferation; Cell Shape; Cells; Complex; Contact Inhibition; Cyclin-Dependent Kinase Inhibitor; Cytoskeleton; Data; Endothelial Cells; Genome; Gentian Violet; Herpesviridae Infections; Human; Human Herpesvirus 8; Individual; Infection; Kaposi Sarcoma; Knowledge; Left; Lymphatic Endothelial Cells; Lytic; Malignant Neoplasms; Measures; Mediating; Mentored Clinical Scientist Development Program; Messenger RNA; MicroRNAs; Modeling; Normal Cell; Oncogenic; Pathway interactions; Phenotype; Process; Proliferating; Proliferation Marker; Proteins; Protocols documentation; Public Health; Repression; Role; Solid Neoplasm; Stains; Study models; Supporting Cell; Testing; Therapeutic; Therapeutic Intervention; Transcript; Viral; Viral Genes; Work; cadherin 5; cell type; gene product; improved; inhibitor; innovation; monolayer; mutant; neoplastic cell; trafficking; tumor; tumorigenesis

SUMMARY Kaposi’s Sarcoma-associated herpesvirus (KSHV) causes the AIDS-defining cancer Kaposi’s Sarcoma (KS). The KSHV-infected KS tumor cells (KSCs) express proliferation markers, indicating a loss of contact inhibition of proliferation (CIP). CIP is considered a tumor suppressive pathway, and loss of CIP is a crucial feature of oncogenic transformation in solid tumors. How KSHV antagonizes CIP is not known. The KS tumor cells most likely originate from microvascular lymphatic endothelial cells (LECs). While LECs therefore represent a relevant model for studies of KS, KSHV-induced proliferation after de novo infection of primary human LECs has not been demonstrated. We have developed a protocol for KSHV infection of primary human LECs that allows us to measure KSHV-induced loss of CIP. The central hypothesis underlying this application is that KSHV-induced loss of CIP is a critical driving feature of oncogenesis in KS. Our preliminary work shows that the KSHV miR-K10 miRNAs contribute substantially to the KSHV-induced loss of CIP in LECs but are not the only viral determinants of this phenotype. Our results furthermore implicate viral repression of p27, disruption of adherens junctions (AJs), and deregulation of the cytoskeleton and vesicular trafficking in KSHV-mediated loss of CIP. To test our hypothesis and elucidate the mechanisms underlying KSHV-induced loss of CIP, we propose three Specific Aims. In Specific Aim 1, we will determine the expression of the four miR-K10 miRNAs in KSHV-infected LECs and KS. We will also define their individual contributions to the KSHV-induced loss of CIP. In Specific Aim 2, we will identify the mechanisms underlying the miR-K10-induced loss of CIP in KSHV- infected LECs. In Specific Aim 3, we will identify other viral genes that promote the KSHV-induced loss of CIP. The proposed study is innovative because our model provides rigorously defined experimental settings that enable the analysis of KSHV-induced loss of CIP after infection of a primary human cell type with relevance to KS. This work is significant because it will establish the viral determinants of KSHV-induced LEC proliferation, thereby explaining oncogenic mechanisms in KS. Results will be impactful since CIP is a tumor-suppressive mechanism. Understanding how KSHV overcomes CIP will help us to explain how KSHV causes KS and could potentially be exploited for therapeutic intervention in KS.

概括 卡波西（Kaposi）与肉瘤相关的疱疹病毒（KSHV）导致定义艾滋病的癌症卡波西（Kaposi）的肉瘤（KS）。 KSHV感染的KS肿瘤细胞（KSC）表达了增殖标记，表明接触抑制作用丧失 增殖（CIP）。 CIP被认为是肿瘤抑制途径，CIP的损失是 实体瘤中的致癌转化。 KSHV如何拮抗CIP。 KS肿瘤细胞最多 可能起源于微血管淋巴内皮细胞（LEC）。因此，lecs代表 KS研究的研究模型，KSHV诱导的原代人LEC的从头感染后的增殖 尚未证明。我们已经开发了一种针对原发性人体LEC感染的KSHV感染方案 允许我们测量KSHV诱导的CIP丢失。该应用程序的基础假设是 KSHV诱导的CIP丢失是KS肿瘤发生的关键驾驶特征。我们的初步工作表明 KSHV miR-k10 miRNA对KSHV诱导的LEC的CIP损失做出了重大贡献，但不是 仅病毒确定这种表型。我们的结果进一步暗示了p27的病毒表达 在KSHV介导的细胞骨架和囊泡运输的粘附连接（AJS）以及放松管制 损失CIP。为了检验我们的假设并阐明了KSHV诱导的CIP损失的机制，我们 提案三个具体目标。在特定目标1中，我们将确定四个miR-K10 miRNA的表达 在KSHV感染的LEC和KS中。我们还将定义他们对KSHV引起的损失的个人贡献 CIP。在特定的目标2中，我们将确定miR-K10诱导的KSHV-中CIP丢失的机制 感染的LEC。在特定目标3中，我们将确定其他促进KSHV诱导的CIP损失的病毒基因。 拟议的研究具有创新性，因为我们的模型提供了严格定义的实验环境 能够分析KSHV诱导的原代人细胞类型后感染与 KS。这项工作很重要，因为它将建立KSHV诱导的LEC增殖的病毒决定剂，即 从而解释了KS中的致癌机制。由于CIP是肿瘤抑制，结果会产生影响 机制。了解KSHV如何克服CIP将有助于我们解释KSHV如何导致KS，并且可以 有可能利用Ks的治疗干预措施。