癌症是一种复杂的多因素疾病，其发病机理涉及多种代谢途径，包括泛素-蛋白酶体系统。目前已经批准了几种蛋白酶体抑制剂用于临床治疗。然而，对现有治疗方法的抵抗力和严重不良反应的发生仍然是一个问题。本研究的目的是发现具有抗癌活性的新型蛋白酶体抑制剂的骨架，以克服现有蛋白酶体抑制剂的局限性。因此，我们开发了一种基于结构的虚拟筛选方案，使用人类20S蛋白酶体的结构，并从虚拟数据库中选择了246个化合物进行离体评价，包括蛋白酶体抑制实验和细胞活力实验。化合物4（JHG58）被选为最佳化合物，基于其在抑制蛋白酶体活性和诱导细胞死亡方面的潜力（两者的IC50值都在低微摩尔范围内）。分子对接研究揭示了化合物4与关键残基的相互作用，包括胺基酸催化活性位点的Thr1、Ala20、Thr21、Lys33和Asp125。这个命中化合物是进一步通过化合物优化研究的良好候选化合物。

Cancer is a complex multifactorial disease whose pathophysiology involves multiple metabolic pathways, including the ubiquitin-proteasome system, for which several proteasome inhibitors have already been approved for clinical use. However, the resistance to existing therapies and the occurrence of severe adverse effects is still a concern. The purpose of this study was the discovery of novel scaffolds of proteasome inhibitors with anticancer activity, aiming to overcome the limitations of the existing proteasome inhibitors. Thus, a structure-based virtual screening protocol was developed using the structure of the human 20S proteasome, and 246 compounds from virtual databases were selected for in vitro evaluation, namely proteasome inhibition assays and cell viability assays. Compound 4 (JHG58) was shortlisted as the best hit compound based on its potential in terms of proteasome inhibitory activity and its ability to induce cell death (both with IC50 values in the low micromolar range). Molecular docking studies revealed that compound 4 interacts with key residues, namely with the catalytic Thr1, Ala20, Thr21, Lys33, and Asp125 at the chymotrypsin-like catalytic active site. The hit compound is a good candidate for additional optimization through a hit-to-lead campaign.