OSU-03012 therapy for glioblastoma

描述(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细胞对放化疗完全反应的相对抵抗力。从非类固醇抗炎药塞来昔布的化学骨架中衍生出一系列化合物，这些化合物不具有COX2抑制活性，但具有高度的生物利用度，可以穿过血脑屏障，在抑制肿瘤细胞活性方面比母药强一个数量级。我们发现，最强的铅化合物OSU-03012在体外对已建立的和原代人的基底膜细胞有很强的诱导性细胞死亡，但对未转化的原代星形胶质细胞或原代肝细胞的培养没有诱导细胞死亡，浓度在1-5M范围内，低于啮齿类动物可达的15-20M的血浆浓度。这种化合物是NCI RAIDA计划选择进行开发的，部分是基于我们的数据，作为单一药物的这种药物的I期试验将于2009年开始在其他肿瘤类型中进行。我们已经在原代和已建立的人肾小球基底膜细胞中证明了OSU-03012在体外抑制短期活性和克隆形成，OSU-03012诱导的杀伤主要通过诱导有毒内质网(ER)应激/自噬信号发生。在体内，我们已经注意到在一个基底膜模型中，OSU-03012可以提高动物的存活率，并与放射治疗相互作用，进一步延长存活期。我们已经发表了OSU-03012的致命性被抑制热休克蛋白90或暴露在电离辐射中而放大。我们假设：格尔达那霉素HSP90激动剂通过ROS和神经酰胺的产生引起CD95的激活，与OSU-03012诱导的毒性自噬平行，这是导致基底膜细胞杀伤的协同作用。我们推测：电离辐射通过促进神经酰胺合成酶基因的表达/激活，从而增强OSU-03012诱导的毒性自噬，从而增强OSU-03012的毒性。具体目标1：将确定热休克蛋白90拮抗剂(格尔达那霉素)17AAG/17DMAG促进OSU-03012对原代人基底膜细胞毒性的分子机制(S)。具体目标2：将确定OSU-03012使原代人类基底膜细胞放射增敏的分子机制，特别关注神经酰胺合成酶基因的调节作用。具体目标3：将使用原代人类基底膜细胞的原位异种移植模型来确定OSU-03012是否在体内增强了电离辐射或17AAG的杀瘤作用。这项建议中的研究目的是提供详细的机制证据，将OSU-03012作为治疗基底膜的药物从试验台转移到临床。 与公共卫生相关：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，该药物作为单一药物的I期试验将于2009年开始，用于各种恶性肿瘤，但不会在基底膜患者中产生任何可能的收益。这项研究的目标是利用原代人肾小球系膜细胞，详细确定OSU-03012作为单一药物和与电离辐射结合的作用机制，以及与格尔达霉素联合抑制热休克蛋白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作为治疗基底膜的药物推向临床。

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.