PDF(Pubmed)
Abstract：
OBJECTIVE: Tumor initiating cells (TICs) or cancer stem cells (CSCs) are considered to be the main culprit of hepatocellular carcinoma (HCC) initiation and progression, nevertheless the mechanism by which tumor microenvironment maintains the HCC \'stemness\' is not fully understood. This study aims to investigate the effect of regulatory T cells (Tregs) on the TICs characteristics of HCC.
METHODS: Immunocytochemistry, flow cytometry, real-time PCR, western blot, in vitro sphere-formation, and in vivo tumorigenesis assay were used to detect HCC \'stemness\'. Additionally, after forced expression or inhibition of FoxP3, β-catenin expression and HCC \'stemness\' were investigated.
RESULTS: Tregs enhanced the \'stemness\' of HCC cells by upregulating TIC-related markers CD133, Oct3/4, Sox2, c-Myc, Klf4, Nanog, CD13, EpCAM, and inducting epithelial to mesenchymal transition (EMT), increasing TICs ratio, as well as promoting tumorigenic ability. Moreover, β-catenin and c-Myc were upregulated in HCC cells after co-cultured with Tregs. HCC \'stemness\' was inhibited after treatment with Wnt/β-catenin pathway inhibitor. Furthermore, forced expression of FoxP3 resulted in increased GSK3β, decreased β-catenin and TIC ratio in HCC. In contrast, FoxP3 interference reduced GSK3β, enhanced β-catenin and TIC ratio of HCC.
CONCLUSIONS: This study, for the first time, demonstrated that Tregs increased the population of TICs in HCC by inhibiting FoxP3 as well as promoting β-catenin expression.
METHODS: Immunocytochemistry, flow cytometry, real-time PCR, western blot, in vitro sphere-formation, and in vivo tumorigenesis assay were used to detect HCC \'stemness\'. Additionally, after forced expression or inhibition of FoxP3, β-catenin expression and HCC \'stemness\' were investigated.
RESULTS: Tregs enhanced the \'stemness\' of HCC cells by upregulating TIC-related markers CD133, Oct3/4, Sox2, c-Myc, Klf4, Nanog, CD13, EpCAM, and inducting epithelial to mesenchymal transition (EMT), increasing TICs ratio, as well as promoting tumorigenic ability. Moreover, β-catenin and c-Myc were upregulated in HCC cells after co-cultured with Tregs. HCC \'stemness\' was inhibited after treatment with Wnt/β-catenin pathway inhibitor. Furthermore, forced expression of FoxP3 resulted in increased GSK3β, decreased β-catenin and TIC ratio in HCC. In contrast, FoxP3 interference reduced GSK3β, enhanced β-catenin and TIC ratio of HCC.
CONCLUSIONS: This study, for the first time, demonstrated that Tregs increased the population of TICs in HCC by inhibiting FoxP3 as well as promoting β-catenin expression.
摘要：
目的：肿瘤起始细胞（TIC）或癌干细胞（CSC）被认为是肝细胞癌（HCC）发生和发展的主要原因，然而，肿瘤微环境维持HCC“干性”的机制尚不完全清楚。本研究旨在探讨调节性T细胞（Tregs）对HCCTIC特性的影响。
方法：免疫细胞化学，流式细胞术,实时PCR，westernblot,体外球体形成，和体内肿瘤发生试验用于检测HCC的“干性”。此外,在强制表达或抑制FoxP3后，研究了β-catenin表达和HCC的“干性”。
结果：Tregs通过上调TIC相关标志物CD133，Oct3/4，Sox2，c-Myc，Klf4,Nanog,CD13,EpCAM,并诱导上皮向间充质转化（EMT），增加TIC比率，以及促进致瘤能力。此外，与Tregs共培养后，肝癌细胞中β-catenin和c-Myc表达上调。用Wnt/β-catenin途径抑制剂治疗后，HCC的“干性”受到抑制。此外，FoxP3的强制表达导致GSK3β增加，肝癌中β-catenin和TIC比率降低。相比之下,FoxP3干扰降低了GSK3β，肝癌β-catenin和TIC比值增强。
结论：这项研究，第一次,证明Tregs通过抑制FoxP3和促进β-catenin表达来增加HCC中TIC的数量。
方法：免疫细胞化学，流式细胞术,实时PCR，westernblot,体外球体形成，和体内肿瘤发生试验用于检测HCC的“干性”。此外,在强制表达或抑制FoxP3后，研究了β-catenin表达和HCC的“干性”。
结果：Tregs通过上调TIC相关标志物CD133，Oct3/4，Sox2，c-Myc，Klf4,Nanog,CD13,EpCAM,并诱导上皮向间充质转化（EMT），增加TIC比率，以及促进致瘤能力。此外，与Tregs共培养后，肝癌细胞中β-catenin和c-Myc表达上调。用Wnt/β-catenin途径抑制剂治疗后，HCC的“干性”受到抑制。此外，FoxP3的强制表达导致GSK3β增加，肝癌中β-catenin和TIC比率降低。相比之下,FoxP3干扰降低了GSK3β，肝癌β-catenin和TIC比值增强。
结论：这项研究，第一次,证明Tregs通过抑制FoxP3和促进β-catenin表达来增加HCC中TIC的数量。
