Department of Biotherapy, Cancer Center, State Key Laboratory of Biotherapy/Collaborative Innovation Center for Biotherapy, West China Hospital, Sichuan University, Chengdu, 610041, China.
Department of Pulmonary and Critical Care Medicine, Targeted Tracer Research and Development Laboratory, Institute of Respiratory Health, Frontiers Science Center for Disease-related Molecular Network, National Clinical Research Center for Geriatrics, State Key Laboratory of Biotherapy, Precision Medicine Key Laboratory of Sichuan Province & Precision Medicine Research Center, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China.
BMC Immunol. 2024 Aug 22;25(1):56. doi: 10.1186/s12865-024-00636-w.
Leukemia inhibitory factor (LIF) is a multifunctional member of the IL-6 cytokine family that activates downstream signaling pathways by binding to the heterodimer consisting of LIFR and gp130 on the cell surface. Previous research has shown that LIF is highly expressed in various tumor tissues (e.g. pancreatic cancer, breast cancer, prostate cancer, and colorectal cancer) and promotes cancer cell proliferation, migration, invasion, and differentiation. Moreover, the overexpression of LIF correlates with poor clinicopathological characteristics. Therefore, we hypothesized that LIF could be a promising target for the treatment of cancer. In this work, we developed the antagonist antibody 1G11 against LIF and investigated its anti-tumor mechanism and its therapeutic efficacy in mouse models.
A series of single-chain variable fragments (scFvs) targeting LIF were screened from a naive human scFv phage library. These scFvs were reconstructed in complete IgG form and produced by the mammalian transient expression system. Among the antibodies, 1G11 exhibited the excellent binding activity to human, cynomolgus monkey and mouse LIF. Functional analysis demonstrated 1G11 could block LIF binding to LIFR and inhibit the intracellular STAT3 phosphorylation signal. Interestingly, 1G11 did not block LIF binding to gp130, another LIF receptor that is involved in forming the receptor complex together with LIFR. In vivo, intraperitoneal administration of 1G11 inhibited tumor growth in CT26 and MC38 models of colorectal cancer. IHC analysis demonstrated that p-STAT3 and Ki67 were decreased in tumor tissue, while c-caspase 3 was increased. Furthermore, 1G11 treatment improves CD3+, CD4 + and CD8 + T cell infiltration in tumor tissue.
We developed antagonist antibodies targeting LIF/LIFR signaling pathway from a naive human scFv phage library. Antagonist anti-LIF antibody exerts antitumor effects by specifically reducing p-STAT3. Further studies revealed that anti-LIF antibody 1G11 increased immune cell infiltration in tumor tissues.
白血病抑制因子（LIF）是白细胞介素 6 细胞因子家族的一种多功能成员，通过与细胞表面的 LIFR 和 gp130 异二聚体结合，激活下游信号通路。先前的研究表明，LIF 在各种肿瘤组织（如胰腺癌、乳腺癌、前列腺癌和结直肠癌）中高度表达，并促进癌细胞增殖、迁移、侵袭和分化。此外，LIF 的过表达与不良的临床病理特征相关。因此，我们假设 LIF 可能是癌症治疗的一个有前途的靶点。在这项工作中，我们开发了针对 LIF 的拮抗剂抗体 1G11，并研究了其抗肿瘤机制及其在小鼠模型中的治疗效果。
从一个原始的人 scFv 噬菌体文库中筛选出一系列针对 LIF 的单链可变片段（scFvs）。这些 scFvs 被重建为完整的 IgG 形式，并通过哺乳动物瞬时表达系统产生。在这些抗体中，1G11 对人、食蟹猴和小鼠 LIF 表现出优异的结合活性。功能分析表明，1G11 可以阻断 LIF 与 LIFR 的结合，并抑制细胞内 STAT3 磷酸化信号。有趣的是，1G11 不会阻断 LIF 与 gp130 的结合，gp130 是另一种 LIF 受体，与 LIFR 一起形成受体复合物。在体内，腹腔内给予 1G11 抑制 CT26 和 MC38 结直肠癌模型中的肿瘤生长。免疫组化分析表明，肿瘤组织中 p-STAT3 和 Ki67 减少，而 c-caspase 3 增加。此外，1G11 治疗可增加肿瘤组织中 CD3+、CD4+和 CD8+T 细胞的浸润。
我们从原始人 scFv 噬菌体文库中开发了针对 LIF/LIFR 信号通路的拮抗剂抗体。拮抗剂抗 LIF 抗体通过特异性降低 p-STAT3 发挥抗肿瘤作用。进一步的研究表明，抗 LIF 抗体 1G11 增加了肿瘤组织中免疫细胞的浸润。
