Wang Yao, Pang Xunlei, Li Ruirui, Chen Jiuzhou, Wen Chen, Zhu Huihuang, Long Tingyu, Li Jianjie, Zheng Lijun, Deng Youcai, Zheng Junnian, Xu Bo
Cancer Institute, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China.
Center of Clinical Oncology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu 221002, China.
Research (Wash D C). 2025 Jan 27;8:0594. doi: 10.34133/research.0594. eCollection 2025.
Chimeric antigen receptor (CAR)-based immune cell therapies attack neighboring cancer cells after receptor recognition but are unable to directly affect distant tumor cells. This limitation may contribute to their inefficiency in treating solid tumors, given the restricted intratumoral infiltration and immunosuppressive tumor microenvironment. Therefore, cell-cell fusion as a cell-killing mechanism might develop a novel cytotherapy aimed at improving the efficacy against solid tumors. We constructed a fusogenic protein, fusion-associated small transmembrane (FAST) p14 of reptilian reovirus, into cancer cells and mesenchymal stem cells (MSCs), which cocultured with various colon cancer cells and melenoma cells to validate its ability to induce cell fusion and syncytia formation. RNA sequencing, quantitative reverse transcription polymerase chain reaction, and Western blot were performed to elucidate the mechanism of syncytia death. Cell viability assay was employed to assess the killing effects of MSCs carrying the p14 protein (MSCs-p14), which was also identified in the subcutaneous tumor models. Subsequently, the Tet-On system was introduced to enhance the controllability and safety of therapy. Cancer cells incorporated with fusogenic protein p14 FAST from reovirus fused together to form syncytia and subsequently died through apoptosis and pyroptosis. MSCs-p14 cocultured with different cancer cells and effienctly induced cancer cell fusion and caused widespread cancer cell death in vitro. In mouse tumor models, mMSCs-p14 treatment markedly suppressed tumor growth and also enhanced the activity of natural killer cells and macrophages. Controllability and safety of MSCs-p14 therapy were further improved by introducing the tetracycline-controlled transcriptional system. MSC-based cytotherapy carrying viral fusogenic protein in this study kills cancer cells by inducing cell-cell fusion. It has demonstrated definite efficacy in treating solid tumors and is worth considering for clinical development.
基于嵌合抗原受体（CAR）的免疫细胞疗法在受体识别后攻击邻近的癌细胞，但无法直接影响远处的肿瘤细胞。鉴于肿瘤内浸润受限和免疫抑制性肿瘤微环境，这一局限性可能导致其在治疗实体瘤时效率低下。因此，细胞间融合作为一种细胞杀伤机制，可能会开发出一种旨在提高实体瘤治疗效果的新型细胞疗法。我们将一种融合蛋白，即来自爬虫类呼肠孤病毒的融合相关小跨膜蛋白（FAST）p14，构建到癌细胞和间充质干细胞（MSC）中，然后将它们与各种结肠癌细胞和黑色素瘤细胞共培养，以验证其诱导细胞融合和多核巨细胞形成的能力。进行RNA测序、定量逆转录聚合酶链反应和蛋白质印迹法以阐明多核巨细胞死亡的机制。采用细胞活力测定法评估携带p14蛋白的间充质干细胞（MSCs-p14）的杀伤效果，这在皮下肿瘤模型中也得到了证实。随后，引入四环素调控系统以提高治疗的可控性和安全性。与来自呼肠孤病毒的融合蛋白p14 FAST整合的癌细胞融合在一起形成多核巨细胞，随后通过凋亡和焦亡死亡。MSCs-p14与不同癌细胞共培养，在体外有效诱导癌细胞融合并导致广泛的癌细胞死亡。在小鼠肿瘤模型中，mMSCs-p14治疗显著抑制肿瘤生长，还增强了自然杀伤细胞和巨噬细胞的活性。通过引入四环素控制的转录系统，进一步提高了MSCs-p14疗法的可控性和安全性。本研究中基于间充质干细胞的携带病毒融合蛋白的细胞疗法通过诱导细胞间融合来杀死癌细胞。它在治疗实体瘤方面已显示出明确的疗效，值得考虑用于临床开发。
