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.

摘要 卡波西肉瘤相关疱疹病毒(KSHV)导致艾滋病定义癌症卡波西肉瘤(KS)。 KSHV感染的KS肿瘤细胞(KSCs)表达增殖标志物，表明失去了接触抑制 增殖率(CIP)。CIP被认为是一种肿瘤抑制途径，CIP的丢失是CIP的一个重要特征 实体瘤的致癌转化。KSHV如何拮抗CIP尚不清楚。KS肿瘤细胞最多 可能来源于微血管淋巴管内皮细胞(LECs)。而LEC因此代表着 KS、KSHV诱导原代人晶状体上皮细胞新生感染后增殖的相关模型研究 还没有被证明。我们已经开发了一种用于原代人类晶状体上皮细胞感染KSHV的方案 使我们能够测量KSHV诱导的CIP的损失。支持这一应用程序的中心假设是 KSHV诱导的CIP缺失是KS肿瘤发生的重要驱动因素。我们的初步工作表明， KSHV miR-K10 miRNAs在KSHV诱导的晶状体上皮细胞CIP丢失中起重要作用，但不是 只有这种表型的病毒决定因素。我们的结果进一步涉及病毒对p27的抑制，中断 KSHV介导的黏附连接(AJ)和细胞骨架和囊泡运输的解除调控 失去CIP。为了验证我们的假设并阐明KSHV导致CIP丢失的机制，我们 提出三个具体目标。在特定的目标1中，我们将确定四个miR-K10 miRNAs的表达 在感染KSHV的LECs和KS中。我们还将定义他们在KSHV导致的损失中的个人贡献 CIP。在特定的目标2中，我们将确定miR-K10诱导KSHV-CIP缺失的潜在机制。 感染的晶状体上皮细胞。在特定的目标3中，我们将寻找促进KSHV诱导的CIP丢失的其他病毒基因。 拟议的研究是创新的，因为我们的模型提供了严格定义的实验设置 能够分析KSHV在感染原代人类细胞类型后引起的CIP丢失与以下因素的相关性 KS.这项工作意义重大，因为它将建立KSHV诱导的LEC增殖的病毒决定因素， 从而解释了KS的致癌机制。结果将是有影响的，因为CIP是一种肿瘤抑制药 机制。了解KSHV是如何战胜CIP的，将有助于我们解释KSHV是如何导致KS的，并可能 有可能被用于KS的治疗干预。