Jia Shijie, Qi Hui, Shang Zhixian, Hua Xinyi, Liang Anping, Tian Yuan, Wu Dingyu, Jiang Yuhong, Liu Xinrong, Mao Canquan
School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, Sichuan Province, PR China.
School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, Sichuan Province, PR China; School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031, Sichuan, PR China.
Bioorg Chem. 2025 Aug;163:108626. doi: 10.1016/j.bioorg.2025.108626. Epub 2025 Jun 4.
FOXM1 (Forkhead box M1), a key transcription factor in the Forkhead box (FOX) family, is overexpressed across multiple cancer types and implicated in nearly all cancer hallmark pathways, making it a promising target for anticancer drug development. In this study, inspired by CP29, a peptide with high affinity to FOXM1-DBD and cytotoxicity to cancer cells, which was recently obtained in our lab by phage peptide library selection, we designed and synthesized a novel and fully peptide-based PROTAC, FPP29, and evaluated its cytotoxicity and molecular mechanisms in liver cancer HCCLM3 cells. CCK-8 assay determined that the IC value of FPP29 for HCCLM3 cells at 24 h was 3.65 ± 0.30 μM which was quite low among current reported FOXM1 inhibitors. Transwell invasion and migration, AO/EB staining, and clone formation experiments showed that FPP29 can promote apoptosis, and strongly inhibit the proliferation, invasion, and migration of HCCLM3 cells. Mechanistically, FPP29 can stably bind to FOXM1 and regulate the expression of FOXM1 and its related genes including cyclin B1, CDC25B, and c-Myc. In addition, FPP29 can enhance FOXM1 poly-ubiquitination and induce its degradation through the ubiquitin-proteasome system. In vivo studies in xenograft mice showed that 15 mg/kg FPP29 inhibited tumor growth by 75 % with no apparent toxicity. Collectively, FPP29 exhibits strong anti-cancer effects in vitro and in vivo, highlighting its promise as a lead compound for FOXM1-targeted therapeutic development with favorable safety profiles.
叉头框M1（FOXM1）是叉头框（FOX）家族中的关键转录因子，在多种癌症类型中均有过表达，且几乎涉及所有癌症标志通路，这使其成为抗癌药物开发的一个有前景的靶点。在本研究中，受CP29启发（CP29是一种对FOXM1-DBD具有高亲和力且对癌细胞具有细胞毒性的肽，最近由我们实验室通过噬菌体肽库筛选获得），我们设计并合成了一种新型的、完全基于肽的PROTAC（FPP29），并评估了其在肝癌HCCLM3细胞中的细胞毒性和分子机制。CCK-8检测确定，FPP29在24小时对HCCLM3细胞的IC值为3.65±0.30μM，在目前报道的FOXM1抑制剂中相当低。Transwell侵袭和迁移实验、AO/EB染色以及克隆形成实验表明，FPP29可促进细胞凋亡，并强烈抑制HCCLM3细胞的增殖、侵袭和迁移。机制上，FPP29可稳定结合FOXM1，并调节FOXM1及其相关基因（包括细胞周期蛋白B1、细胞周期蛋白依赖性激酶25B和c-Myc）的表达。此外，FPP29可增强FOXM1的多聚泛素化，并通过泛素-蛋白酶体系统诱导其降解。在异种移植小鼠中的体内研究表明，15mg/kg的FPP29可抑制肿瘤生长75%，且无明显毒性。总体而言，FPP29在体外和体内均表现出强大的抗癌作用，突出了其作为具有良好安全性的FOXM1靶向治疗开发先导化合物的潜力。
