Kaposi'sarcoma (KS) is the most common cancer in AIDS patients, and is associated with infection of Kaposi's sarcoma-associated herpesvirus (KSHV/HHV8). KS is a highly angiogenic vascular neoplasm primarily consisting of proliferating spindle endothelial cells with vast inflammatory infiltration. The long-term goal of our research program is to understand the molecular mechanism of KSHV-induced pathogenesis, providing a scientific basis for developing effective preventive and therapeutic approaches. Recent studies have shown that angiogenesis and inflammation are two central components in KS pathogenesis, and KSHV infection modulates these processes through a paracrine mechanism by inducing pro-angiogenic and inflammatory factors. The objective of this application is to define the mechanisms by which KSHV induces angiogenesis, and identify potential therapeutic targets for KSHV-induced malignancies. Our preliminary studies have shown that KSHV infection of human umbilical vein endothelial cells induces secretion of pro-angiogenic factors and represses secretion of angiogenesis inhibitors. Importantly, we have found that pro-angiogenic factors angiopoietin-2 (Ang-2), interleukin-6 (IL-6), and matrix metalloproteinase-1 (MMP-1) are highly induced by KSHV, and are also highly expressed in KS tumors. Significantly, we have shown that blocking Ang-2 alone with a neutralization antibody abolishes KSHV-induced paracrine-dependent angiogenesis in vivo. We hypothesize that KSHV infection induces angiogenesis through a paracrine mechanism by expressing specific viral gene products to modulate cellular angiogenic pathways, and as a result, targeting these angiogenic pathways can inhibit KSHV- induced tumorigenesis. To test this hypothesis, we will identify KSHV-regulated pro-angiogenic factors and angiogenesis inhibitors essential for KSHV-induced angiogenesis (aim I);determine the cellular pathways that mediate KSHV regulation of Ang-2, IL-6 and MMP-1 in latent infection (aim II);and identify viral genes that regulate the expression of Ang-2 (aim III). Finally, we will test the therapeutic applications of inhibiting KSHV-induced specific angiogenic pathways in tumor animal models (aim IV). The proposed project is innovative because it will use comprehensive multidisciplinary approaches to identify viral and cellular pathways, and pro-angiogenic factors/angiogenesis inhibitors that control KSHV-induced angiogenesis. These studies are significant because it will not only define the mechanism(s) of KSHV-induced angiogenesis but also identify potential therapeutic targets for KSHV-induced malignancies.

Public Health Relevance

Kaposi's sarcoma is a common malignancy in AIDS patients in US and worldwide inflicting morbidity and mortality to the society. This project will investigate the mechanism underlining the development of Kaposi's sarcoma, and identify potential targets for the prevention and treatment of this disease.

National Institute of Health (NIH)
National Cancer Institute (NCI)
Research Project (R01)
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Special Emphasis Panel (ZRG1-AARR-C (04))
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Ogunbiyi, Peter
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University of Texas Health Science Center San Antonio
Schools of Medicine
San Antonio
United States
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Yuan, Hongfeng; Tan, Brandon; Gao, Shou-Jiang (2017) Tenovin-6 impairs autophagy by inhibiting autophagic flux. Cell Death Dis 8:e2608
Yuan, Hongfeng; He, Meilan; Cheng, Fan et al. (2017) Tenovin-6 inhibits proliferation and survival of diffuse large B-cell lymphoma cells by blocking autophagy. Oncotarget 8:14912-14924
Jeon, Hyungtaek; Yoo, Seung-Min; Choi, Hyo Sun et al. (2017) Extracellular vesicles from KSHV-infected endothelial cells activate the complement system. Oncotarget 8:99841-99860
Li, W; Hu, M; Wang, C et al. (2017) A viral microRNA downregulates metastasis suppressor CD82 and induces cell invasion and angiogenesis by activating the c-Met signaling. Oncogene 36:5407-5420
Zhu, Ying; Li, Tingting; Ramos da Silva, Suzane et al. (2017) A Critical Role of Glutamine and Asparagine ?-Nitrogen in Nucleotide Biosynthesis in Cancer Cells Hijacked by an Oncogenic Virus. MBio 8:
He, Meilan; Tan, Brandon; Vasan, Karthik et al. (2017) SIRT1 and AMPK pathways are essential for the proliferation and survival of primary effusion lymphoma cells. J Pathol 242:309-321
Gruffaz, Marion; Vasan, Karthik; Tan, Brandon et al. (2017) TLR4-Mediated Inflammation Promotes KSHV-Induced Cellular Transformation and Tumorigenesis by Activating the STAT3 Pathway. Cancer Res 77:7094-7108
Zhu, Ying; Ramos da Silva, Suzane; He, Meilan et al. (2016) An Oncogenic Virus Promotes Cell Survival and Cellular Transformation by Suppressing Glycolysis. PLoS Pathog 12:e1005648
Li, Wan; Yan, Qin; Ding, Xiangya et al. (2016) The SH3BGR/STAT3 Pathway Regulates Cell Migration and Angiogenesis Induced by a Gammaherpesvirus MicroRNA. PLoS Pathog 12:e1005605
Yan, Qin; Shen, Chenyou; Qin, Jie et al. (2016) HIV-1 Vpr Inhibits Kaposi's Sarcoma-Associated Herpesvirus Lytic Replication by Inducing MicroRNA miR-942-5p and Activating NF-?B Signaling. J Virol 90:8739-53

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