Osteosarcoma frequently presents as recurrence and metastasis, even if the primary lesion was eradicated and/or radiotherapy and chemotherapy were administered. Osteosarcoma cancer stem cells (CSCs) are one of the key factors for the recurrence and metastasis of osteosarcoma. We have shown that interleukin-24 (IL-24) inhibits osteosarcoma cell proliferation, migration and invasion in vitro. In the current study, we investigated the role of IL-24 in inhibiting the growth of osteosarcoma CSCs. IL-24 inhibited proliferation and invasion and decreased the stemness of osteosarcoma CSCs in vitro. In a nude mouse xenograft model, IL-24 significantly inhibited the growth of tumors originating from osteosarcoma CSCs. Moreover, we found that IL-24 was able to inactivate both Notch and Wnt/β-Catenin signaling, which are important for the development of the biological characteristics of CSCs. These data demonstrate that IL-24 is able to kill not only cancer cells but also CSCs in osteosarcoma, suggesting that IL-24 might eradicate osteosarcoma and enhance long-term cure rates in patients with osteosarcoma.

骨肉瘤经常表现为复发和转移，即使原发病灶已被根除和/或进行了放疗和化疗。骨肉瘤癌干细胞（CSCs）是骨肉瘤复发和转移的关键因素之一。我们已经证明白细胞介素 24 (IL-24) 在体外抑制骨肉瘤细胞增殖、迁移和侵袭。在目前的研究中，我们研究了 IL-24 在抑制骨肉瘤 CSC 生长中的作用。IL-24 在体外抑制骨肉瘤 CSCs 的增殖和侵袭并降低其干性。在裸鼠异种移植模型中，IL-24 显着抑制源自骨肉瘤 CSC 的肿瘤的生长。此外，我们发现 IL-24 能够使 Notch 和 Wnt/β-Catenin 信号通路失活，这对 CSCs 生物学特性的发展很重要。这些数据表明，IL-24 不仅能够杀死骨肉瘤中的癌细胞，还能够杀死 CSC，表明 IL-24 可能根除骨肉瘤并提高骨肉瘤患者的长期治愈率。