Development of small molecule epigenetic therapeutics for prostate cancer

雄激素受体(AR)变异体AR-V7的产生及糖皮质激素受体的激活 前列腺癌(Pca)细胞的GR信号转导和从上皮细胞向神经内分泌细胞的谱系转换有三个方面 前列腺癌细胞逃避雄激素受体靶向治疗的新机制 途径抑制物(ARPI)。在前列腺癌中，没有针对这些机制的药物或流水线药物 治疗学。我们先前和初步的研究表明，组蛋白赖氨酸去甲基酶KDM4B是 与这些机制相关，可能是去势耐药前列腺癌的可用药靶点 (CRPC)。KDM4B促进细胞周期基因、AR-V7和神经内分泌标志物的表达。遗传 KDM4B的失活或药物抑制下调这些基因的表达 抑制CRPC增长。我们已经产生了原型KDM4B抑制剂B3，它有效地抑制了 AR阴性神经内分泌样PC3异种移植瘤的体内生长B3还抑制22Rv1的生长 去势小鼠高表达AR和AR-V7并与GR有协同作用的肿瘤 拮抗剂CORT125134。为了提高B3的选择性和有效性，我们进行了多轮 基于结构的虚拟筛选、计算分析、化学合成和基于细胞的初级筛选。 从&gt；200种化合物中，我们确定了另外3种先导化合物，它们提高了KDM驱动的IC50 与B3相比，细胞生长受到抑制。这些化学物质的合成及其在肿瘤学中的应用 已经申请了专利保护。在这里，我们将测试这些先导化合物对各种前列腺的疗效。 异种移植模型及其ADME(吸收、分布、代谢和排泄)和 药代动力学-药效学(PK/PD)特性具有两个特定的目的。目的1.确定疗效 和候选化合物的酶选择性。我们将测试B3和B3类似物在异种移植中的疗效 源自具有不同程度雄激素反应性的PCA模型。我们还包括非 并以前列腺癌HeLa细胞为对照，进行rna-seq以鉴定常见和前列腺癌特有基因。 与候选化合物关联的签名。候选人的选择性将接受测试，看其是否有能力 在脱甲基酶测定中抑制特定的KDM酶活性。目的2.建立物理、化学和生物化学方法 候选化合物的ADME性质。候选人的毒品特征将包括其 理化性质、体外代谢稳定性、细胞通透性、血浆蛋白结合和PK/PD 属性。该提案结果将为我们提供信息以确定生物标记物定义的亚群(S) 并评价靶向治疗对PCa患者的影响。这些信息还将指导我们设计和 优化给药途径和药物处方，并在人体内进行PK/PD建模 二、IND预科学习。里程碑：我们将根据先导化合物的有效性、选择性和 ADME/PK/Pd的性能，并将名单上排名前两位的化合物(S)推进到第二阶段研究。

Generation of constitutively active androgen-receptor (AR)-variant AR-V7, activation of glucocorticoid receptor (GR) signaling, and lineage switch from epithelial to neuroendocrine of prostate cancer (PCa) cells are three emerging mechanisms by which prostate tumor cells use to evade targeted therapy with androgen-receptor pathway inhibitors (ARPIs). There are no drugs or pipeline-agents that target these mechanisms in PCa therapeutics. Our previous and preliminary studies indicate that histone lysine demethylase KDM4B is associated with these mechanisms and may be a druggable target in castration-resistant prostate cancer (CRPC). KDM4B promotes the expression of cell cycle genes, AR-V7, and neuroendocrine markers. Genetic inactivation or pharmacological inhibition of KDM4B downregulates the expression of these genes and suppresses CRPC growth. We have generated proto-type KDM4B inhibitor B3 that effectively inhibited the growth of AR-negative and neuroendocrine-like PC3 xenograft in vivo. B3 also suppresses the growth of 22Rv1 tumor that expresses high levels of AR and AR-V7 in castrated mice and has synergistic effect with the GR antagonist CORT125134. To improve the selectivity and efficacy of B3, we performed multiple rounds of structure-based virtual screening, computational analyses, chemical synthesis, and primary cell-based screens. From >200 chemical compounds, we identified 3 more lead compounds that have improved IC50 on KDM-driven cell growth inhibition compared to that of B3. The synthesis of these chemical entities and their use in oncology have been filed for patent protection. Here we will test the efficacy of these lead compounds in various prostate xenograft models and characterize their ADME (Absorption, distribution, metabolism, and excretion) and pharmacokinetics-pharmacodynamics (PK/PD) properties with two specific aims. Aim 1. To establish the efficacy and enzymatic selectivity of candidate compound. We will test the efficacy of B3 and B3-analogs in xenografts derived from PCa models that have various degree of androgen responsiveness. We also include the non- prostate HeLa cells as a control and will perform RNA-seq to identify common and prostate cancer unique gene signature associated with the candidate compound. Selectivity of the candidate will be tested for its ability to inhibit specific KDM enzymatic activity in the demethylase assay. Aim 2. To establish the physiochemical and ADME properties of candidate compound. The drug-likeness of the candidate will be characterized including its physiochemical properties, in vitro metabolic stability, cell permeability, plasma protein binding, and PK/PD properties. The outcome of the proposal will provide us information to identify biomarker-defined subgroup(s) of PCa patients and to evaluate the effect of targeted therapy. The information will also guide us in designing and optimizing the drug-delivery route and drug formulation and performing PK/PD modeling in human in the phase II pre-IND studies. Milestone: We will prioritize the lead compounds based on their efficacy, selectivity, and ADME/PK/PD properties and take top one/two compound(s) on the list forward to phase II studies.