OSU-03012 therapy for glioblastoma

描述（由申请人提供）：多形性胶质母细胞瘤（GBM）是最致命的恶性肿瘤之一，部分原因是其高度侵袭性，以及GBM细胞对放疗或化疗完全应答的相对抗性。已经从NSAID塞来昔布的化学骨架衍生出一系列化合物，其不具有COX 2抑制活性，但具有高度生物利用度，可以穿过血脑屏障，并且在抑制肿瘤细胞活力方面比母体药物更有效一个数量级。我们已经证明，最有效的先导化合物OSU-03012在体外建立的和原代人GBM细胞中引起强烈的诱导细胞死亡，但在非转化的原代星形胶质细胞或原代肝细胞的培养物中不引起强烈的诱导细胞死亡，浓度在1-5 μ M范围内，这低于啮齿动物中该药剂可达到的1-5 -20 μ M血浆浓度。NCI RAID计划选择了这种化合物进行开发，部分基于我们的数据，并且将于2009年开始在其他肿瘤类型中进行这种药物作为单一药物的I期试验。我们已经在原代和已建立的人GBM细胞中证明，OSU-03012在体外抑制短期活力和集落形成，并且OSU-03012诱导的杀伤主要通过诱导毒性内质网（ER）应激/自噬信号发生。在体内，我们在一个GBM模型中注意到OSU-03012可以提高动物存活率并与放射疗法相互作用以进一步延长存活率。我们已经发表了OSU-03012的致死性通过抑制HSP 90或暴露于电离辐射而放大。我们假设：格尔德霉素HSP 90激动剂通过ROS和神经酰胺产生导致CD 95活化，与OSU-03012诱导的毒性自噬平行，这是GBM细胞杀伤协同作用的原因。我们假设：电离辐射通过促进神经酰胺合酶基因的表达/激活来增强OSU-03012毒性，所述神经酰胺合酶基因增强OSU-03012诱导的毒性自噬。具体目标1：将确定暴露于HSP 90拮抗剂（格尔德霉素）17 AAG/17 DMAG促进OSU-03012在原代人GBM细胞中毒性的分子机制。具体目标二：将确定OSU-03012放射增敏原代人GBM细胞的分子机制，特别关注神经酰胺合酶基因的调节作用。具体目标3：将使用原代人GBM细胞的原位异种移植模型确定OSU-03012是否增强电离辐射或17 AAG的体内杀肿瘤作用。本提案中研究的目标是提供详细的机制证据，将OSU-03012作为GBM治疗药物从实验室转移到临床。 公共卫生相关性：OSU-03012于2008年被授权给一家生物技术公司（Arno），部分基于我们在三篇手稿中发表的数据，并且将于2009年开始在各种恶性肿瘤中进行该药物作为单一药物的I期试验，但在GBM患者中没有任何可能的增加。本提案中研究的目的是使用原代人GBM细胞在分子细节上确定OSU-03012作为单一药物和与电离辐射联合使用的作用机制;以及与格尔德霉素联合使用抑制HSP 90功能的作用机制。我们的目标是提供详细的机制证据，将OSU-03012作为GBM的治疗药物推向临床。

DESCRIPTION (provided by applicant): Glioblastoma multiforme (GBM) is one of the most lethal malignancies in part due to its highly invasive nature and due to the relative resistance of GBM cells to fully respond to radio- or chemo-therapies. A series of compounds have been derived from the chemical backbone of the NSAID Celecoxib that do not possess COX2 inhibitory activity, but are highly bio-available, can cross the blood-brain barrier, and are an order of magnitude more potent at suppressing tumor cell viability than the parent drug. We have shown that the most potent lead compound, OSU-03012, causes a strong induction cell death in established and primary human GBM cells in vitro, but not in cultures of non-transformed primary astrocytes or primary hepatocytes, at concentrations in the 1-5 ¿M range, which is lower than the 15-20 ¿M achievable plasma concentration of this agent in rodents. This compound was selected by the NCI RAID program for development, in part based on our data, and a phase I trial with this drug as a single agent will commence in other tumor types in 2009. We have demonstrated in primary and established human GBM cells that OSU-03012 suppresses short-term viability and colony formation in vitro and that OSU-03012 -induced killing occurs primarily via in the induction of a toxic endoplasmic reticulum (ER) stress / autophagy signal. In vivo we have noted in one GBM model that OSU-03012 can enhance animal survival and interact with radiotherapy to further prolong survival. We have published that the lethality of OSU-03012 is magnified by inhibition of HSP90 or by exposure to ionizing radiation. We hypothesize that: geldanamycin HSP90 agonists via ROS and ceramide production cause CD95 activation in parallel to OSU-03012 -induced toxic autophagy which is responsible for the synergy of GBM cell killing. We hypothesize that: ionizing radiation enhances OSU-03012 toxicity by promoting expression/ activation of ceramide synthase genes which enhances OSU-03012 -induced toxic autophagy. Specific Aim 1: Will determine the molecular mechanism(s) by which OSU-03012 toxicity in primary human GBM cells is promoted by exposure to the HSP90 antagonists (geldanamycins) 17AAG / 17DMAG. Specific Aim 2: Will determine the molecular mechanisms by which OSU-03012 radio-sensitizes primary human GBM cells with specific focus on the regulatory roles of ceramide synthase genes. Specific Aim 3: Will determine, using orthotopic xenograft models of primary human GBM cells, whether OSU-03012 enhances the tumoricidal effects of ionizing radiation or of 17AAG, in vivo. The goal of the studies in this proposal is to provide detailed mechanistic evidence to move OSU-03012 as a therapeutic for GBM from the bench into the clinic. PUBLIC HEALTH RELEVANCE: OSU-03012 was licensed in 2008 to a biotechnology company (Arno) in part based on our data published in three manuscripts, and a phase I trial with this drug as a single agent will commence in 2009 in a variety of malignancies but not with any likely accrual in GBM patients. The goal of the studies in this proposal is to determine in molecular detail using primary human GBM cells the mechanisms of action of OSU-03012 as a single agent and in combination with ionizing radiation; and in combination with geldanamycins to inhibit HSP90 function. Our goal is to provide detailed mechanistic evidence to move OSU-03012 as a therapeutic for GBM into the clinic.