Reproductive Medicine Center, Department of Obstetrics and Gynecology, Nanfang Hospital/The First School of Clinical Medicine, Southern Medical University, Guangzhou, 510515, China.
Department of Neurology, Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510315, China.
BMC Cancer. 2018 Jul 25;18(1):763. doi: 10.1186/s12885-018-4563-7.
Bladder cancer often recurs due to incomplete elimination of the cancer stem cells (CSCs). Therefore, new strategies targeting bladder CSCs are needed and the aim of this study was to investigate the effect of S100A4 on the proliferation capacity of MB49 bladder cancer stem cells (MCSCs).
MCSCs were established and validated. The expression level of S100A4 in MCSCs and MB49 cells was evaluated using Western blotting and quantitative polymerase chain reaction (QPCR). S100A4 was overexpressed or knocked-down by transfection of pCMV6-XL5-S100A4 plasmid or RNA interference (RNAi) respectively. Proliferation capacity of MCSC was evaluated by cell proliferation assay and in vivo tumorigenicity study. Transcriptional activity of nuclear factor kappa B (NF-κB) was analyzed using luciferase reporter assay, and the level of interleukin (IL)-2 as well as tumor necrosis factor (TNF) was quantified by QPCR. Protein-protein interaction of S100A4 and inhibitor of nuclear factor kappa B NF-κB kinase (IKK) was analyzed by immunoprecipitation.
S100A4 was significantly up-regulated in MCSCs, which positively associated with the proliferation capacity, as well as the level of NF-κB, IKK, IL-2 and TNF in MCSCs. Knock-down of S100A4 could reverse such effects. Using immunoprecipitation assay, an interaction between S100A4 and IKK could be observed.
S100A4 is upregulated in MCSCs and possibly enhance the proliferation ability of MCSCs by way of activating the IKK/NF-κB signaling pathway, and S100A4 maybe a hopeful therapeutic target for MCSCs.
膀胱癌常因癌症干细胞（CSC）清除不完全而复发。因此，需要针对膀胱 CSC 的新策略，本研究旨在探讨 S100A4 对 MB49 膀胱癌细胞（MCSC）增殖能力的影响。
建立和验证 MCSC。采用 Western blot 和实时定量聚合酶链反应（QPCR）检测 MCSC 和 MB49 细胞中 S100A4 的表达水平。通过转染 pCMV6-XL5-S100A4 质粒或 RNA 干扰（RNAi）分别过表达或敲低 S100A4。通过细胞增殖实验和体内肿瘤形成研究评估 MCSC 的增殖能力。采用荧光素酶报告基因检测分析核因子κB（NF-κB）的转录活性，通过 QPCR 定量白细胞介素（IL）-2 和肿瘤坏死因子（TNF）的水平。通过免疫沉淀分析 S100A4 与核因子κB 激酶抑制剂（IKK）的蛋白-蛋白相互作用。
S100A4 在 MCSC 中显著上调，与 MCSC 的增殖能力以及 NF-κB、IKK、IL-2 和 TNF 的水平呈正相关。敲低 S100A4 可逆转这种作用。通过免疫沉淀实验观察到 S100A4 与 IKK 之间的相互作用。
S100A4 在 MCSC 中上调，并可能通过激活 IKK/NF-κB 信号通路增强 MCSC 的增殖能力，S100A4 可能是 MCSC 的一个有希望的治疗靶点。
