Li Ka Shing Faculty of Medicine, Department of Orthopaedics and Traumatology, The University of Hong Kong, Hong Kong SAR, China.
Department of Orthopedic Surgery, The First Affiliated Hospital of Nanchang University, Nanchang, China.
Mol Carcinog. 2018 Feb;57(2):262-271. doi: 10.1002/mc.22753. Epub 2017 Nov 2.
Osteosarcoma (OS) is the most common malignant tumor that develops in bone. Its mortality is very high. Therefore, study of mechanisms of pathogenesis of the OS is urgently required. Previous studies of microarray showed that the expression levels of matrix metallopeptidase 9 (MMP-9) altered significantly in OS. In addition, overexpression of MMP-9 is recognized as an indicator in cancer. However, the exact roles of MMP-9 in OS are not fully investigated. Thus, we firstly studied the roles of MMP-9 in OS and revealed that silence of MMP-9 inhibited OS cell proliferation as determined by MTT assay and colony formation assay. Secondly, we conducted TUNEL assay and confirmed loss of functions of MMP-9 induced OS cell apoptosis. Next, we used lentivector packaging method to overexpress MMP-9 and found that overexpression of MMP-9 promoted OS cell migration. Fourthly, the results of luciferase assay showed that MMP-9 was targeted by hsa-miR-494, which inhibited OS. Fifthly, we revealed that the levels of hsa-miR-494 were upregulated by the drug silybin which inhibited OS. Finally, we revealed that silybin inhibited OS cell viability by altering the protein levels of β-catenin and Runt-related transcription factor 2 (RUNX2) as determined by western blot and immunocytochemistry (ICC).
骨肉瘤（OS）是最常见的发生在骨骼的恶性肿瘤。其死亡率非常高。因此，迫切需要研究 OS 的发病机制。微阵列的先前研究表明，基质金属蛋白酶 9（MMP-9）的表达水平在 OS 中发生显著改变。此外，MMP-9 的过表达被认为是癌症的一个指标。然而，MMP-9 在 OS 中的确切作用尚未完全研究。因此，我们首先研究了 MMP-9 在 OS 中的作用，并通过 MTT 测定和集落形成测定证实沉默 MMP-9 抑制 OS 细胞增殖。其次，我们进行了 TUNEL 测定，并证实 MMP-9 的功能丧失诱导 OS 细胞凋亡。接下来，我们使用慢病毒包装方法过表达 MMP-9，发现 MMP-9 的过表达促进了 OS 细胞的迁移。第四，荧光素酶测定的结果表明 MMP-9 是 hsa-miR-494 的靶点，hsa-miR-494 抑制 OS。第五，我们揭示了 silybin 通过改变 OS 中β-连环蛋白和 runt 相关转录因子 2（RUNX2）的蛋白水平来上调 hsa-miR-494 的水平，这是通过 Western blot 和免疫细胞化学（ICC）测定的。最后，我们揭示了 silybin 通过改变β-连环蛋白和 runt 相关转录因子 2（RUNX2）的蛋白水平来抑制 OS 细胞活力，这是通过 Western blot 和免疫细胞化学（ICC）测定的。
