Department of Orthopedic Traumatology, General Hospital of Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region 750004, P.R. China.
Department of Orthopedics, Zhangye People's Hospital Affiliated to Hexi University, Zhangye, Gansu 734000, P.R. China.
Mol Med Rep. 2022 Feb;25(2). doi: 10.3892/mmr.2021.12569. Epub 2021 Dec 16.
Osteosarcoma is a primary bone tumor that mainly occurs in children and adolescents. Absent in melanoma 2 (AIM2) has been demonstrated to be involved in regulating the occurrence and development of cancer, exerting oncogenic and pro‑cancer effects; however, its role in osteosarcoma is poorly understood. The present study aimed to explore the function and molecular mechanism of AIM2 in the progression of osteosarcoma. In the present study, AIM2 expression was predicted using the Cancer Cell Line Encyclopedia database and examined in several osteosarcoma cell lines using reverse transcription‑quantitative PCR and western blotting. Following AIM2 overexpression, cell proliferation and apoptosis were examined using Cell Counting Kit‑8, colony formation and TUNEL staining assays. The expression levels of proteins related to apoptosis, epithelial‑mesenchymal transition (EMT) and the PI3K/AKT/mTOR signaling pathway were determined by western blotting. Additionally, cell invasion and migration were assessed using Transwell and wound healing assays. After addition of the PI3K/AKT/mTOR signaling pathway inhibitor LY294002 or activator 740Y‑P, cell function analysis was performed. The results demonstrated that AIM2 was expressed at low levels in osteosarcoma cell lines. AIM2 overexpression inhibited proliferation, invasion, migration and EMT, and promoted apoptosis in osteosarcoma cells. Furthermore, the levels of phosphorylated (p)‑PI3K, p‑AKT and p‑mTOR were markedly downregulated following AIM2 overexpression. Furthermore, LY294002 treatment had the same effects as AIM2 upregulation on osteosarcoma cell proliferation, apoptosis, invasion, migration and EMT. By contrast, 740Y‑P reversed the effects of AIM2 overexpression on the behavior of osteosarcoma cells. Overall, the findings of the present study demonstrated that AIM2 may inhibit the progression of osteosarcoma by inactivating the PI3K/AKT/mTOR signaling pathway, and suggested that AIM2 may be a promising marker for the treatment of osteosarcoma.
骨肉瘤是一种主要发生在儿童和青少年的原发性骨肿瘤。缺失在黑色素瘤 2（AIM2）已被证明参与调节癌症的发生和发展，发挥致癌和促进癌症的作用；然而，其在骨肉瘤中的作用知之甚少。本研究旨在探讨 AIM2 在骨肉瘤进展中的功能和分子机制。在本研究中，使用癌症细胞系百科全书数据库预测 AIM2 的表达，并使用逆转录-定量 PCR 和蛋白质印迹法检测几种骨肉瘤细胞系中的 AIM2 表达。在过表达 AIM2 后，使用细胞计数试剂盒-8、集落形成和 TUNEL 染色测定法检测细胞增殖和凋亡。通过蛋白质印迹法测定与凋亡、上皮-间充质转化（EMT）和 PI3K/AKT/mTOR 信号通路相关的蛋白表达水平。此外，使用 Transwell 和划痕愈合测定法评估细胞侵袭和迁移。添加 PI3K/AKT/mTOR 信号通路抑制剂 LY294002 或激活剂 740Y-P 后，进行细胞功能分析。结果表明，AIM2 在骨肉瘤细胞系中低表达。AIM2 过表达抑制骨肉瘤细胞的增殖、侵袭、迁移和 EMT，并促进细胞凋亡。此外，AIM2 过表达后，磷酸化（p）-PI3K、p-AKT 和 p-mTOR 的水平明显下调。此外，LY294002 处理对骨肉瘤细胞增殖、凋亡、侵袭、迁移和 EMT 的作用与 AIM2 过表达相同。相比之下，740Y-P 逆转了 AIM2 过表达对骨肉瘤细胞行为的影响。总体而言，本研究结果表明，AIM2 可能通过使 PI3K/AKT/mTOR 信号通路失活来抑制骨肉瘤的进展，并且表明 AIM2 可能是治疗骨肉瘤的有前途的标志物。
