As epigenetic readers, bromodomain and extra-terminal domain (BET) family proteins bind to acetylated-lysine residues in histones and recruit protein complexes to promote transcription initiation and elongation. Inhibition of BET bromodomains by small molecule inhibitors has emerged as a promising therapeutic strategy for cancer. Herein, we describe our efforts toward the discovery of a novel series of 1-(5-(1H-benzo[d]imidazole-2-yl)-2,4-dimethyl-1H-pyrrol-3-yl)ethan-1-one derivatives as BET inhibitors. Intensive structural modifications led to the identification of compound 35f as the most active inhibitor of BET BRD4 with selectivity against BET family proteins. Further biological studies revealed that compound 35f can arrest the cell cycle in G₀/G₁ phase and induce apoptosis via decreasing the expression of c-Myc and other proteins related to cell cycle and apoptosis. More importantly, compound 35f showed favorable pharmacokinetic properties and antitumor efficacy in MV4-11 mouse xenograft model with acceptable tolerability. These results indicated that BET inhibitors could be potentially used to treat hematologic malignancies and some solid tumors.

作为表观遗传阅读器，溴结构域和末端外结构域 (BET) 家族蛋白与组蛋白中的乙酰化赖氨酸残基结合并募集蛋白质复合物以促进转录起始和延伸。通过小分子抑制剂抑制 BET 溴结构域已成为一种有前途的癌症治疗策略。在这里，我们描述了我们为发现一系列新的 1-(5-(1 H -benzo[ d ]imidazole-2-yl)-2,4-dimethyl-1 H -pyrrol-3-yl)ethan 所做的努力-1-one 衍生物作为 BET 抑制剂。密集的结构修饰导致化合物35f被鉴定为对 BET 家族蛋白具有选择性的最活跃的 BET BRD4 抑制剂。进一步的生物学研究表明，化合物35f通过降低c-Myc等细胞周期和细胞凋亡相关蛋白的表达，使细胞周期停滞在G ₀ /G ₁期，诱导细胞凋亡。更重要的是，化合物35f在 MV4-11 小鼠异种移植模型中显示出良好的药代动力学特性和抗肿瘤功效，具有可接受的耐受性。这些结果表明，BET 抑制剂可能潜在地用于治疗血液系统恶性肿瘤和一些实体瘤。