Sarcoma Biology Laboratory, Department of Orthopaedic Surgery, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts.
Department of Emergency Surgery, ShenZhen People's Hospital, 2nd Clinical Medical College of Jinan University, Shenzhen, Guangdong Province, China.
Clin Cancer Res. 2017 Sep 1;23(17):5176-5186. doi: 10.1158/1078-0432.CCR-17-0177. Epub 2017 Jun 12.
Conventional chemotherapeutic agents are ineffective in the treatment of chordoma. We investigated the functional roles and therapeutic relevance of the sex-determining region Y (SRY)-box 9 (SOX9) in chordoma. SOX9 expression was examined by immunohistochemistry (IHC) using 50 chordoma tissue samples. SOX9 expression in chordoma cell lines was examined by Western blot and immunofluorescent assays. We used synthetic human SOX9 siRNA to inhibit the expression of SOX9. Cell proliferation ability and cytotoxicity of inhibiting SOX9 were assessed by 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (MTT) and clonogenic assays. The effect of SOX9 knockdown on chordoma cell motility was evaluated by a wound-healing assay and a Transwell invasion chamber assay. Knockdown of SOX9 induced apoptosis, cell-cycle arrest, as well as decreased expression of cancer stem cell markers were determined by Western blot and flow cytometric assays. The effect of the combination of SOX9 siRNA and the chemotherapeutic drug doxorubicin/cisplatin on chordoma cells was assessed by an MTT assay. Tissue microarray and IHC analysis showed that SOX9 is broadly expressed in chordomas and that higher expression levels of SOX9 correlated with a poor prognosis. RNA interference (RNAi)-mediated knockdown of SOX9 inhibited chordoma cell growth, decreased cell motility, and induced apoptosis as well as cell-cycle arrest. Moreover, the combination of SOX9 inhibition and chemotherapeutic drugs had an enhanced anti-cancer effect on chordoma cells. Our results demonstrate that SOX9 plays a crucial role in chordoma. Targeting SOX9 provides a new rationale for treatment of chordoma. .
传统化疗药物在治疗脊索瘤方面无效。我们研究了性别决定区 Y (SRY)-盒 9 (SOX9) 在脊索瘤中的功能作用和治疗相关性。使用 50 例脊索瘤组织样本通过免疫组织化学（IHC）检查 SOX9 的表达。通过 Western blot 和免疫荧光测定检查 SOX9 在脊索瘤细胞系中的表达。我们使用合成的人 SOX9 siRNA 抑制 SOX9 的表达。通过 3-(4,5-二甲基噻唑基-2)-2,5-二苯基四唑溴盐（MTT）和集落形成测定评估抑制 SOX9 对脊索瘤细胞增殖能力和细胞毒性的影响。通过划痕愈合测定和 Transwell 侵袭室测定评估 SOX9 敲低对脊索瘤细胞迁移的影响。通过 Western blot 和流式细胞术测定确定 SOX9 敲低诱导细胞凋亡、细胞周期停滞以及降低癌症干细胞标志物的表达。通过 MTT 测定评估 SOX9 siRNA 与化疗药物阿霉素/顺铂联合对脊索瘤细胞的影响。组织微阵列和 IHC 分析表明，SOX9 在脊索瘤中广泛表达，并且 SOX9 表达水平较高与预后不良相关。RNA 干扰（RNAi）介导的 SOX9 敲低抑制脊索瘤细胞生长、降低细胞迁移并诱导细胞凋亡和细胞周期停滞。此外，SOX9 抑制和化疗药物的联合使用对脊索瘤细胞具有增强的抗癌作用。我们的结果表明 SOX9 在脊索瘤中发挥关键作用。靶向 SOX9 为治疗脊索瘤提供了新的依据。
