Abstract：
Phosphatidylinositide-3-kinase (PI3K) and the mammalian target of rapamycin (mTOR) have recently been identified as potential cancer targets. In our work, a new family of quinoline analogues was designed, developed, and evaluated as dual inhibitors of PI3Kδ/mTOR. The preliminary biological activity analysis led to the discovery of the lead compounds 5h and 5e. Compounds 5h and 5e exhibited excellent anti-tumor potency with IC50 of 0.26 µM and 0.34 µM against Ramos cells, respectively. Importantly, based on the enzymatic activity assay results, compounds 5h and 5e were identified as dual inhibitors of PI3Kδ and mTOR, with IC50 values of 0.042 µM and 0.056 µM for PI3Kδ and 0.059 µM and 0.073 µM for mTOR, respectively. Furthermore, these compounds showed superior selectivity for blocking PI3Kδ compared to other PI3K isoforms (α, β, and γ), supporting the concept of developing inhibitors that specifically target PI3Kδ/mTOR. The most effective compound 5h was chosen for additional biological testing. At a low dose of 0.5 µM, a western blot investigation confirmed the anticancer effects by inhibiting the PAM cascade, which in turn reduced downstream biomarkers pAkt (Ser473), pAkt (Thr308), and pRPS6 (Ser235/236). Furthermore, it increased apoptosis at the early (10.03 times) and late (17.95 times) stages in the Annexin-V assay as compared to the standard. In addition, the expression of p53, caspase-3, caspase-9, and the Bax/BCl-2 ratio were all significantly increased by compound 5h in the ELISA assay. Based on these results, it appears that 5h may activate the intrinsic apoptosis pathway, which in turn triggers cell death. Furthermore, the anticancer effects could be attributed to the inhibition of PI3Kδ/mTOR, as shown by docking interactions. Lastly, it demonstrated improved in vitro metabolic stability and passed the in silico ADMET/drug-likeness test. This profile recommends 5h for future in vivo PK-PD and efficacy investigations in animal cancer models.
摘要：
磷脂酰肌肽-3-激酶(PI3K)和哺乳动物雷帕霉素靶标(mTOR)最近已被鉴定为潜在的癌症靶标。在我们的工作中,设计了一个新的喹啉类似物家族，开发,并评价为PI3Kδ/mTOR的双重抑制剂。初步的生物活性分析导致发现了先导化合物5h和5e。化合物5h和5e表现出优异的抗肿瘤效力，对Ramos细胞的IC50为0.26µM和0.34µM，分别。重要的是,根据酶活性测定结果，化合物5h和5e被鉴定为PI3Kδ和mTOR的双重抑制剂，PI3Kδ的IC50值为0.042µM和0.056µM，mTOR的IC50值为0.059µM和0.073µM，分别。此外，与其他PI3K同工型相比，这些化合物对阻断PI3Kδ表现出优异的选择性(α，β,和γ)，支持开发特异性靶向PI3Kδ/mTOR的抑制剂的概念。选择最有效的化合物5h用于另外的生物学测试。在0.5µM的低剂量下，一项蛋白质印迹研究证实了通过抑制PAM级联的抗癌作用，这反过来又降低了下游生物标志物pAkt(Ser473)，pAkt(Thr308),和pRPS6(Ser235/236)。此外，与标准相比,它在膜联蛋白-V测定的早期(10.03倍)和晚期(17.95倍)阶段增加了细胞凋亡。此外,在ELISA试验中,化合物5h可显著增加p53、caspase-3、caspase-9的表达和Bax/BCl-2比值。基于这些结果,似乎5h可能激活内在的凋亡途径，进而引发细胞死亡。此外，抗癌作用可归因于抑制PI3Kδ/mTOR，如对接交互所示。最后,它证明了改善的体外代谢稳定性，并通过了计算机模拟ADMET/药物相似度测试。该概况推荐5小时用于动物癌症模型中的未来体内PK-PD和功效研究。
