Department of Orthopedics, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shanxi, 710004, China; Department of Orthopedics, The East Area of First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shanxi, 710089, China.
Department of Orthopedics, The East Area of First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shanxi, 710089, China.
Biomed Pharmacother. 2019 Jul;115:108949. doi: 10.1016/j.biopha.2019.108949. Epub 2019 May 14.
Osteosarcoma is the most frequent malignant bone cancer in teenagers. In this study, cell division cycle 6 (Cdc6) was upregulated in the tumor tissues from patients with osteosarcoma according to the results of RNA sequencing. Cdc6 has been considered as a candidate prognostic marker, which was associated with cell apoptosis and cell cycle. However, the mechanisms by which Cdc6 regulates the apoptosis and cell cycle arrest in osteosarcoma remain unclear.
Firstly, 3 pairs of osteosarcoma and adjacent normal tissues were subjected to RNA sequencing. In addition, the levels of Cdc6 in 30 pairs of patients' tissues and in osteosarcoma cell lines were detected by western blotting and RT-qPCR. Moreover, the effects of Cdc6 on cell proliferation, apoptosis, cell cycle and invasion were evaluated by cell counting kit-8 (CCK-8), flow cytometric and transwell assay, respectively.
Cdc6 was significantly upregulated in patients with osteosarcoma and in osteosarcoma cell lines. Downregulation of Cdc6 inhibited the proliferation and invasion of MG63 cells by promoting apoptosis. In addition, downregulation of Cdc6 induced G1 phase cell cycle arrest. Moreover, inhibition of Cdc6 downregulated the expression of Cyclin D1 and Cyclin A2, and upregulated the level of p21 in MG63 cells. In vivo study confirmed downregulation of Cdc6 inhibited osteosarcoma tumor growth by inducing apoptosis.
Our findings indicated that Cdc6 may serve as an oncogene in osteosarcoma. Thus, inhibiting Cdc6 may be a therapeutic approach for the treatment of osteosarcoma.
骨肉瘤是青少年中最常见的恶性骨癌。在这项研究中，根据 RNA 测序的结果，骨肉瘤患者的肿瘤组织中细胞分裂周期蛋白 6（Cdc6）上调。Cdc6 已被认为是候选预后标志物，与细胞凋亡和细胞周期有关。然而，Cdc6 调节骨肉瘤细胞凋亡和细胞周期阻滞的机制尚不清楚。
首先，对 3 对骨肉瘤和相邻正常组织进行 RNA 测序。此外，通过 Western blot 和 RT-qPCR 检测 30 对患者组织和骨肉瘤细胞系中 Cdc6 的水平。此外，通过细胞计数试剂盒-8（CCK-8）、流式细胞术和 Transwell 测定分别评估 Cdc6 对细胞增殖、凋亡、细胞周期和侵袭的影响。
Cdc6 在骨肉瘤患者和骨肉瘤细胞系中明显上调。下调 Cdc6 通过促进细胞凋亡抑制 MG63 细胞的增殖和侵袭。此外，下调 Cdc6 诱导 G1 期细胞周期停滞。此外，抑制 Cdc6 下调了 MG63 细胞中细胞周期蛋白 D1 和 A2 的表达，上调了 p21 的水平。体内研究证实下调 Cdc6 通过诱导细胞凋亡抑制骨肉瘤肿瘤生长。
我们的研究结果表明，Cdc6 可能在骨肉瘤中作为癌基因发挥作用。因此，抑制 Cdc6 可能是治疗骨肉瘤的一种方法。
