Small Molecule Inhibitors of K13-Induced NF-kB Activation

卡波西肉瘤相关疱疹病毒（KSHV），也称为人类疱疹病毒8 (HHV8)，是艾滋病患者中最常见的恶性肿瘤。KSHV感染与卡波西肉瘤（KS）和几种淋巴增生性疾病的发生有关，包括原发性积液淋巴瘤（PEL）、多中心Castleman病和免疫母细胞/浆母细胞淋巴瘤。由于潜在的免疫抑制，kshv相关癌症在常规化疗治疗时预后极差，迫切需要更有效、毒性更小的治疗方法。然而，KSHV在这些疾病发病机制中的确切作用机制尚不清楚。我们发现K13是一种kshv编码的vFLIP（病毒FLICE抑制蛋白），具有独特的激活经典和替代NF-？B途径通过与I？B激酶（IKK）复合物。我们进一步证明，K13是一种致癌基因，可介导细胞增殖、转化、细胞因子分泌增加，并通过NF？B激活。因此，我们认为K13在kshv相关淋巴增生性疾病的发病机制中起着关键作用，是开发分子靶向治疗的理想候选者。本提案的主要目标是开发一种高通量的检测方法来分离k13诱导的NF？B活化和测试他们的能力，阻断其生物活性使用测定建立在我们的实验室。我们希望这些研究不仅能使我们更好地了解K13的各种生物学功能，而且还能鉴定出毒性更小、更有效的分子靶向药物来治疗kshv相关的癌症。卡波西肉瘤相关疱疹病毒（KSHV）感染与许多人类癌症有关。该项目的目标是开发一种筛选试验，以确定K13的抑制剂，K13是该病毒编码的关键蛋白。这些抑制剂将有助于更好地了解kshv相关癌症发病机制中的K13蛋白，并开发出更有效的治疗药物。

DESCRIPTION (provided by applicant): PROJECT SUMMARY Kaposi's sarcoma associated herpes virus (KSHV), also known as Human herpes virus 8 (HHV8), is the most frequent cause of malignancy among AIDS patients. Infection with KSHV has been linked to the occurrence of Kaposi's sarcoma (KS) and several lymphoproliferative disorders including primary effusion lymphoma (PEL), multicentric Castleman's disease and immunoblastic/plasmablastic lymphomas. Because of underlying immunosuppression, KSHV-associated cancers have extremely poor prognosis when treated with conventional chemotherapy and there is urgent need for more effective and less toxic therapies for these disorders. However, the exact mechanism of action of KSHV in the pathogenesis of these disorders is still unclear. We have discovered that K13, a KSHV-encoded vFLIP (viral FLICE inhibitory protein), possesses the unique abilities to activate the classical and alternative NF-?B pathways by interacting with different components of the I?B kinase (IKK) complex. We have further demonstrated that K13 is an oncogene that mediates increased cellular proliferation, transformation, cytokine secretion and protection against growth factor withdrawal-induced apoptosis via NF?B activation. Thus, we believe that K13 is a pivotal player in the pathogenesis of KSHV-associated lymphoproliferative disorders and an ideal candidate for development of molecularly targeted therapies. The primary goal of this proposal is to develop a high throughput assay to isolate small molecule inhibitors of K13-induced NF?B activation and test their ability to block its biological activities using assays established in our laboratory. We hope that these studies will not only lead to a better understanding of the various biological functions of K13 but also to the identification of less toxic and more effective molecularly targeted agents for the treatment of KSHV-associated cancers. PROJECT NARRATIVE Infection with the Kaposi's sarcoma associated herpesvirus (KSHV) has been linked to a number of human cancers. The goal of this project is to develop a screening assay to identify inhibitors of K13, a key protein encoded by this virus. Such inhibitors will lead to a better understanding of the K13 protein in the pathogenesis of KSHV-associated cancers and to the development of more effective drugs for their treatment.