Filipová Marcela, Tavares Marina Rodrigues, Hovorková Michaela, Heine Viktoria, Nekvasilová Pavlína, Křen Vladimír, Etrych Tomáš, Chytil Petr, Bojarová Pavla
Department of Biological Models, Institute of Macromolecular Chemistry of the Czech Academy of Sciences, Prague, Czech Republic.
Department of Biomedical Polymers, Institute of Macromolecular Chemistry of the Czech Academy of Sciences, Prague, Czech Republic.
Int J Nanomedicine. 2025 May 24;20:6591-6609. doi: 10.2147/IJN.S503381. eCollection 2025.
The immunosuppressive roles of galectin-3 (Gal-3) in carcinogenesis make this lectin an attractive target for pharmacological inhibition in immunotherapy. Although current clinical immunotherapies appear promising in the treatment of solid tumors, their efficacy is significantly weakened by the hostile immunosuppressive tumor microenvironment (TME). Gal-3, a prominent TME modulator, efficiently subverts the elimination of cancer, either directly by inducing apoptosis of immune cells or indirectly by binding essential effector molecules, such as interferon-gamma (IFNγ).
-(2-Hydroxypropyl)methacrylamide (HPMA)-based glycopolymers bearing poly--acetyllactosamine-derived tetrasaccharide ligands of Gal-3 were designed, synthesized, and characterized using high-performance liquid chromatography, dynamic light scattering, UV-Vis spectrophotometry, gel permeation chromatography, nuclear magnetic resonance, high-resolution mass spectrometry and CCK-8 assay for evaluation of glycopolymer non-toxicity. Pro-immunogenic effects of purified glycopolymers were tested by apoptotic assay using flow cytometry, competitive ELISA, and in vitro cell-free INFγ-based assay.
All tested glycopolymers completely inhibited Gal-3-induced apoptosis of monocytes/macrophages, of which the M1 subtype is responsible for eliminating cancer cells during immunotherapy. Moreover, the glycopolymers suppressed Gal-3-induced capture of glycosylated IFNγ by competitive inhibition to Gal-3 carbohydrate recognition domain (CRD), which enables further inherent biological activities of this effector, such as differentiation of monocytes into M1 macrophages and repolarization of M2-macrophages to the M1 state.
The prepared glycopolymers are promising inhibitors of Gal-3 and may serve as important supportive anti-cancer nanosystems enabling the infiltration of proinflammatory macrophages and the reprogramming of unwanted M2 macrophages into the M1 subtype.
半乳糖凝集素-3（Gal-3）在肿瘤发生过程中的免疫抑制作用，使得这种凝集素成为免疫治疗中药物抑制的一个有吸引力的靶点。尽管目前的临床免疫疗法在实体瘤治疗中显示出前景，但它们的疗效因恶劣的免疫抑制肿瘤微环境（TME）而显著减弱。Gal-3是一种重要的TME调节因子，它通过诱导免疫细胞凋亡或间接结合关键效应分子（如干扰素-γ（IFNγ））有效地破坏癌症清除过程。
设计、合成并表征了基于聚（2-羟丙基）甲基丙烯酰胺（HPMA）的糖聚合物，其带有Gal-3的聚乙酰乳糖胺衍生四糖配体，使用高效液相色谱、动态光散射、紫外-可见分光光度法、凝胶渗透色谱、核磁共振、高分辨率质谱和CCK-8测定法评估糖聚合物的无毒性。通过流式细胞术凋亡测定、竞争性ELISA和基于体外无细胞IFNγ的测定法测试纯化糖聚合物的促免疫原性作用。
所有测试的糖聚合物完全抑制了Gal-3诱导的单核细胞/巨噬细胞凋亡，其中M1亚型在免疫治疗期间负责清除癌细胞。此外，糖聚合物通过对Gal-3碳水化合物识别域（CRD）的竞争性抑制，抑制了Gal-3诱导的糖基化IFNγ的捕获，这使得该效应分子的进一步内在生物学活性得以实现，如单核细胞分化为M1巨噬细胞以及M2巨噬细胞重新极化至M1状态。
所制备的糖聚合物是有前景的Gal-3抑制剂，并且可作为重要的支持性抗癌纳米系统，能够促进促炎巨噬细胞浸润以及将不需要的M2巨噬细胞重编程为M1亚型。
