Bone Department, The First Affiliated Hospital of Zhengzhou University, China.
Int J Surg. 2015 Aug;20:80-7. doi: 10.1016/j.ijsu.2015.04.050. Epub 2015 Apr 30.
To investigate the role of P53 in the pathogenesis of osteosarcoma and the possible mechanism involved in it.
The anti-proliferative effect of P53 was assessed using the cell counting Kit-8 assay. The migration and invasion potential were analyzed using wound-healing and transwell assays, respectively. The Matrigel capillary tube formation assay was performed to mimic in-vivo angiogenesis. Immunoblotting and immunofluorescence were used to observe protein levels and distribution of actin fibers. Finally, S2448p-mammalian target of rapamycin (mTOR) expression was detected on osteosarcoma tissues using immunohistochemistry.
Firstly, P53 potently inhibited cell proliferation in osteosarcoma cell line (MG63) and in human normal osteoblasts (hFOB1.19) in vitro at the IC50 ranged from 50 to 500 nmol/l. Then, an inhibitory effect of P53 on metastasis was observed in osteosarcoma cell line MG63, along with the cytoskeletal rearrangements and suppression of the phosphorylation of PI3K downstream factors including AKT and mTOR.
These results show that P53 suppresses cell proliferation and angiogenesis of osteosarcoma through inhibition of the PI3K/AKT/mTOR pathway, which might be an effective novel therapeutic candidate against osteosarcoma in the future.
研究 P53 在骨肉瘤发病机制中的作用及其可能涉及的机制。
使用细胞计数试剂盒-8 检测 P53 的抗增殖作用。分别通过划痕愈合和 Transwell 分析检测迁移和侵袭潜能。通过 Matrigel 毛细管形成实验模拟体内血管生成。免疫印迹和免疫荧光用于观察肌动蛋白纤维的蛋白水平和分布。最后，使用免疫组织化学检测骨肉瘤组织中 S2448p-哺乳动物雷帕霉素靶蛋白（mTOR）的表达。
首先，P53 在体外以 50 至 500nmol/L 的 IC50 浓度强烈抑制骨肉瘤细胞系（MG63）和人正常成骨细胞（hFOB1.19）的细胞增殖。然后，观察到 P53 对骨肉瘤细胞系 MG63 的转移具有抑制作用，同时伴随着细胞骨架重排和抑制 PI3K 下游因子包括 AKT 和 mTOR 的磷酸化。
这些结果表明，P53 通过抑制 PI3K/AKT/mTOR 通路抑制骨肉瘤的细胞增殖和血管生成，这可能是未来针对骨肉瘤的一种有效新型治疗候选药物。
