Original Phase 1 Title: Identifying Small Molecule Inhibitors of HdmX using Cell-based Screening Revised Title: Development of a Novel HdmX Inhibitor for Leukemia

 描述（由申请人提供）：尽管癌症治疗取得了进步，但大多数使用的癌症治疗剂仍然表现出显着的毒性并诱导 DNA 损伤。 DNA 损伤虽然对非恶性细胞有毒，但通常通过诱导 p53 在杀死癌细胞中发挥重要作用。最近，为了开发毒性较小且更具针对性的癌症疗法，已经提出了诱导 p53 的替代策略。一种策略涉及破坏 p53 与其负调节因子 HdmX 和/或 Hdm2 的相互作用。在我们的第一阶段资助中，我们发现了 CTX1，一种新型的 HdmX/p53 小分子抑制剂，它可以破坏 HdmX/p53 相互作用，并以非 DNA 损伤依赖性方式导致 p53 诱导和癌细胞死亡。 CTX1可以直接与HdmX相互作用并优先杀死表达p53的癌细胞。正如预期的那样，同时抑制 Hdm2 可增强 CTX1 的活性。尽管如此，该化合物即使作为单药在循环原发性人类 AML 小鼠模型中也表现出有希望的活性。该提案的目标是开发我们在临床试验第一阶段资助期间确定的 HdmX 抑制剂的优化版本。该提案的目的是通过小鼠功效、药代动力学和毒性研究评估该药物的临床潜力。希望这项工作将导致 IND 研究的启动和 1 期临床试验的启动。

 DESCRIPTION (provided by applicant): Despite advances in cancer therapy, the majority of cancer therapeutics in use still exhibit significant toxicity and induce DNA damage. The DNA damage, though toxic to non-malignant cells, often plays an important role in killing cancer cells through the induction of p53. Recently, in order to develop less toxic and more targeted cancer therapies, alternative strategies to induce p53 have been proposed. One strategy involves disrupting p53 interactions with its negative regulators, HdmX and/or Hdm2. In our phase 1 grant we identified, CTX1, a novel small molecule inhibitor of HdmX/p53 that can disrupt HdmX/p53 interactions and lead to p53 induction and cancer cell death in a non-DNA damage dependent fashion. CTX1 can directly interact with HdmX and preferentially kill cancer cells expressing p53. As expected, the activity of CTX1 is enhanced by concurrent Hdm2 inhibition. Nonetheless, this compound demonstrates promising activity even as a single agent in a mouse model of circulating primary human AML. The goal of this proposal is to develop an optimized version of our HdmX inhibitor that we identified during our phase 1 grant towards clinical trials. The aims of this proposal are to assess the clinical potential of this agent through mouse efficacy, pharmacokinetic and toxicity studies. It is hoped that this work will lead to the initiaton of IND-enabling studies and the initiation of a phase 1 clinical trial.