The Key Laboratory of Carcinogenesis of the Chinese Ministry of Health, The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Department of Hematology, Xiangya Hospital; Cancer Research Institute, School of Basic Medical Sciences, Central South University, Changsha, 410078, China.
Shanghai Center for Bioinformation Technology, Shanghai Academy of Science and Technology, Shanghai, 201203, China.
Cell Oncol (Dordr). 2021 Jun;44(3):643-659. doi: 10.1007/s13402-021-00590-4. Epub 2021 Mar 1.
Bone marrow stromal cells (BMSCs) have been implicated in multiple myeloma (MM) progression. However, the underlying mechanisms remain largely elusive. Therefore, we aimed to explore key factors in BMSCs that contribute to MM development.
RNA-sequencing was used to perform gene expression profiling in BMSCs. Enzyme-linked immunosorbent assays (ELISAs) were performed to determine the concentrations of PGE2 and TNFα in sera and conditioned media (CM). Western blotting, qRT-PCR and IHC were used to examine the expression of cyclooxygenase 2 (COX2) in BMSCs and to analyze the regulation of TNFα by COX2. Cell growth and adhesion assays were employed to explore the function of COX2 in vitro. A 5T33MMvt-KaLwRij mouse model was used to study the effects of COX2 inhibition in vivo.
COX2 was found to be upregulated in MM patient-derived BMSCs and to play a critical role in BMSC-induced MM cell proliferation and adhesion. Administration of PGE2 to CM derived from BMSCs promoted MM cell proliferation and adhesion. Conversely, inhibition of COX2 in BMSCs greatly compromised BMSC-induced MM cell proliferation and adhesion. PCR array-based analysis of inflammatory cytokines indicated that COX2 upregulates the expression of TNFα. Subsequent rescue assays showed that an anti-TNFα monoclonal antibody could antagonize COX2-mediated MM cell proliferation and adhesion. Administration of NS398, a specific COX2 inhibitor, inhibited in vivo tumor growth and improved the survival of 5TMM mice.
Our results indicate that COX2 contributes to BMSC-induced MM proliferation and adhesion by increasing the secretion of PGE2 and TNFα. Targeting COX2 in BMSCs may serve as a potential therapeutic approach of treating MM.
骨髓基质细胞（BMSCs）被认为与多发性骨髓瘤（MM）的进展有关。然而，其潜在机制在很大程度上仍难以捉摸。因此，我们旨在探讨 BMSCs 中促进 MM 发展的关键因素。
使用 RNA 测序对 BMSCs 进行基因表达谱分析。酶联免疫吸附测定（ELISA）用于测定血清和条件培养基（CM）中 PGE2 和 TNFα 的浓度。Western blot、qRT-PCR 和 IHC 用于检测 BMSCs 中环氧化酶 2（COX2）的表达，并分析 COX2 对 TNFα 的调节作用。细胞生长和粘附实验用于体外研究 COX2 的功能。使用 5T33MMvt-KaLwRij 小鼠模型研究 COX2 抑制在体内的作用。
COX2 在 MM 患者来源的 BMSCs 中上调，并在 BMSC 诱导的 MM 细胞增殖和粘附中发挥关键作用。将 PGE2 给予 BMSC 来源的 CM 可促进 MM 细胞增殖和粘附。相反，COX2 在 BMSCs 中的抑制极大地削弱了 BMSC 诱导的 MM 细胞增殖和粘附。基于 PCR 阵列的炎症细胞因子分析表明，COX2 上调 TNFα 的表达。随后的挽救实验表明，抗 TNFα 单克隆抗体可拮抗 COX2 介导的 MM 细胞增殖和粘附。给予特异性 COX2 抑制剂 NS398 可抑制体内肿瘤生长并改善 5TMM 小鼠的生存。
我们的结果表明，COX2 通过增加 PGE2 和 TNFα 的分泌促进 BMSC 诱导的 MM 增殖和粘附。靶向 BMSCs 中的 COX2 可能是治疗 MM 的一种潜在治疗方法。
