新型2-氨基-4-苯氨基嘧啶类JAK/HDAC双靶点抑制剂的设计、合成与抗肿瘤活性研究

Small molecular targeting drugs are the significant subject of cancer chemotherapy. Due to serious side effects and drug resistance of early targeting agents, it is urgent to develop safe and effective ones. Recently, HDAC inhibitors have become the research hotspot of cancer targeting drugs. However, the treatment of HDAC inhibitors is only effective in hematologic malignancies, while frustrated in solid tumors. Studies have shown that feedback activation of the JAK-STAT signaling pathway lead to the fact that solid tumors are not sensitive to HDAC inhibitors. Therefore, JAK inhibition can significantly enhance the activity of HDAC inhibitors against solid tumors. In this study, the JAK inhibitor Fedratinib was selected as a core moiety, and the classic pharmacophore of HDAC inhibitor was recruited to develop the JAK/HDAC dual-target inhibitors. The significance and rationality of the designed compounds was demonstrated by CADD, then the inhibitory activity of compounds in HDAC and JAK isoforms were further explored to clarify the structure-activity relationship. Finally, the privilege molecules will be evaluated in diverse cell lines of hematologic malignancies and solid tumors, and assayed for activity in vivo at animal levels, as well as investigated for mechanism of action. The safe and efficient JAK/HDAC dual-target inhibitors will play a synergistic role in hematologic malignancies, and expand the application in solid tumors, which will provide a theoretical basis for the development of novel antitumor agents with clinical potential.

小分子靶向药物是肿瘤化疗领域的重要课题，但早期靶向药物副作用大、耐药性强，因此急需开发安全有效的新型靶向药物。近年来HDAC抑制剂成为肿瘤靶向药物领域的研究热点，但目前其治疗领域局限于血液肿瘤，对实体瘤的治疗几乎无效。研究表明反馈激活JAK-STAT通路致使实体瘤对HDAC抑制剂治疗不敏感，因此抑制JAK通路的激活可以直接增强HDAC抑制剂的抗实体肿瘤活性。据此，本项目选用JAK抑制剂Fedratinib为母核，结合HDAC抑制剂药效团及计算机辅助药物设计，开发JAK/HDAC双靶点抑制剂。通过对各HDAC及JAK亚型酶水平的抑制活性阐明构效关系，得到优选化合物，进一步在血液瘤及实体瘤细胞系中进行广谱评估、动物体内抗肿瘤活性研究以及机制研究，探索得到安全高效的JAK/HDAC双靶点抑制剂，发挥其对血液肿瘤协同作用，并拓展至实体瘤治疗，为研发具有临床潜力的新型抗肿瘤药物提供理论依据。

近年来HDAC抑制剂成为肿瘤靶向药物领域的研究热点，但目前其治疗领域局限于血液肿瘤，对实体瘤的治疗几乎无效。研究表明抑制JAK通路的激活可以直接增强HDAC抑制剂的抗实体肿瘤活性。据此，本项目选用JAK抑制剂Fedratinib为母核，结合HDAC抑制剂药效团及计算机辅助药物设计，开发合成了一系列JAK/HDAC双靶点抑制剂。通过对JAK2和HDAC1酶水平的初步筛选，结合化合物对多株血液和实体瘤细胞的抑制活性得到两个优选化合物I-C15和I-C24。在进一步的机制研究中发现，I-C15和I-C24可以显著促进血液和实体瘤细胞的凋亡，增加Ac-H3的表达，抑制p-STAT3-Tyr705的表达。此外，化合物I-C15和I-C24在JAK和HDAC亚型中对JAK2和HDAC6有高度选择性，且在激酶谱中对其他激酶几乎没有抑制作用。大鼠药代动力学结果表明，化合物15和24均有较好的口服生物利用度。并且优选化合物在体内也表现出很强的肿瘤抑制作用，为血液肿瘤和实体肿瘤的靶向化疗提供线索，具有很高的临床应用价值。