ANTICANCER DRUG DISCOVERY THAT TARGETS TUMOR HYPOXIA

项目总结 拟议研究的目标是发现、表征和验证天然小分子。 产品衍生的缺氧诱导因子-1(HIF-1)抑制剂作为癌症治疗的辅助药物。从长远来看 目标是开发专门针对肿瘤缺氧(低氧)的癌症化疗药物 紧张)。实体瘤含有缺氧区，缺氧程度与恶性程度相关 疾病进展、对放射治疗和化疗的抗药性以及疾病复发。低氧相关 治疗抵抗可由细胞氧浓度降低直接或间接引起。 通过低氧诱导的基因表达修饰。我们提出了一种新的方法，专门针对 缺氧的这种重要的间接作用(肿瘤基因表达的改变)。在中国没有批准的药物 专门针对缺氧的临床应用。 这一药物发现计划将天然产物化学与尖端生物医学独特地结合在一起。 研究。特定目标1将评估富含天然产物的提取物，分离和阐明该化学物质 抑制低氧诱导和/或结构性激活HIF-1的活性导联的结构，原理 在低氧条件下激活适应和生存基因表达的转录因子。不仅 HIF-1是否促进低氧肿瘤的生存和转移，HIF-1的致癌激活也与此相关 恶性进展和治疗耐药。富含天然产品的提取物将在一个小组中进行检查 高通量的HIF-1抑制活性(低氧诱导和致癌激活)生物检测方法。 活性化合物将通过生物测定引导的分离来分离，并使用 光谱学和光谱学方法的结合。原则性证明已由 发现一些最有效的小分子HIF-1抑制剂。具体目标2将决定效果 活性化合物对低氧肿瘤细胞存活、血管生成和转移的影响。一组肿瘤细胞系 代表不同疾病阶段和低氧反应性的模型将被用作体外模型。无毒 体外抑制低氧肿瘤细胞存活、血管生成和转移的活性化合物将进一步 在基因工程小鼠乳腺癌模型中进行了研究。《特定目标3》将调查 天然产物衍生的缺氧诱导因子抑制剂作为化疗药物辅助剂的治疗潜力。 我们的目标是确定HIF-1抑制剂与低剂量化疗的最佳组合，以实现 低毒抑制肿瘤生长的最大效果。具体目标4将描述自然 产物衍生的HIF抑制剂在分子和细胞水平上并解析其作用机制。 实现这些目标将提供抗肿瘤药物线索和分子探针，将提供新的 对介导低氧信号的细胞内通路的洞察。

PROJECT SUMMARY The objective of the proposed research is to discover, characterize, and validate small molecule natural product-derived hypoxia-inducible factor-1 (HIF-1) inhibitors as adjunct agents for cancer therapy. The longterm goal is to develop cancer chemotherapeutic agents that specifically target tumor hypoxia (low oxygen tension). Solid tumors contain hypoxic regions and the extent of hypoxia correlates with malignant progression, resistance to radiation treatment and chemotherapy, and relapse of the disease. Hypoxiaassociated treatment resistance can be caused directly by reduced cellular oxygen concentrations or indirectly by hypoxia-induced modifications in gene expression. We propose a new approach that specifically targets this important indirect effect of hypoxia (alteration of tumor gene expression). There is no approved drug in clinical use that specifically targets hypoxia. This drug discovery program uniquely combines natural products chemistry with cutting edge biomedical research. Specific Aim 1 will evaluate natural product-rich extracts, isolate and elucidate the chemical structures of active leads that inhibit hypoxia-induced and/or constitutively activated HIF-1, the principle transcription factor that activates the expression of adaptation and survival genes under hypoxia. Not only does HIF-1 promote hypoxic tumor survival and metastasis, oncogenic activation of HIF-1 is also associated with malignant progression and treatment resistance. Natural product-rich extracts will be examined in a panel of high-throughput bioassays for HIF-1 inhibitory activities (hypoxia-induced and oncogenically activated). Active compounds will be isolated through bioassay-guided isolation, and their structures elucidated using a combination of spectroscopic and spectrometric methods. Proof of principle has been established by the discovery of some of the most potent small molecule HIF-1 inhibitors. Specific Aim 2 will determine the effects of active compounds on hypoxic tumor cell survival, angiogenesis, and metastasis. A panel of tumor cell lines that represent different disease stages and hypoxia responsiveness will be used as in vitro models. Nontoxic active compounds that inhibit hypoxic tumor cell survival, angiogenesis, and metastasis in vitro will be further investigated in genetically engineered murine breast cancer models. Specific Aim 3 will investigate the therapeutic potential of natural product-derived HIF inhibitors as adjunct agents with chemotherapeutic agents. The goal is to identify the optimal combination of HIF-1 inhibitors with low dose chemotherapy that can achieve the maximum efficacy of inhibiting tumor growth with low toxicity. Specific Aim 4 will characterize natural product-derived HIF inhibitors at the molecular and cellular levels and resolve the mechanisms of action. Accomplishing these objectives will provide antitumor drug leads and molecular probes that will afford new insights into the intracellular pathways that mediate hypoxic signaling.