Department of Plastic and Reconstructive Surgery, Kansai Medical University, 2-5-1 Shin-machi, Hirakata, Osaka, 573-1010, Japan.
International Joint Research Laboratory for Cell Medical Engineering of Henan, Kaifeng, Henan, 475-000, China.
Stem Cell Res Ther. 2019 Nov 27;10(1):350. doi: 10.1186/s13287-019-1462-z.
Human adipose-derived stem cells (hASCs) are a subset of mesenchymal stem cells (MSCs); it has been regarded as one of the most promising stem cells. We previously found that fibroblast growth factor-2 (FGF-2) enhanced the proliferation and differentiation of hASC. However, the mechanisms involved in the growth of hASCs by FGF-2 have not been investigated.
Human adipose-derived stem cells (hASCs) were cultured with FGF-2, and cell growth was assessed. Effects of FGF Receptor (FGFR) inhibitor (NVP-BGJ398), ERK1/2 inhibitor (PD98059), PI3K/Akt inhibitor (LY294002), JNK inhibitor (SP600125), and p38 MAPK inhibitor (SB203580) and Src inhibitor (PP1) on the proliferation were investigated. At the same time, we assessed the effect of FGFR inhibitor on several signaling enzymes such as ERK1/2, JNK, p38, and Akt, in protein level. The involvement of Src activation by FGF-2 was also examined.
FGF-2 markedly promoted proliferation of hASCs at concentrations lower than 10 ng/ml and stimulated cell progression to the S and G2/M phases. Proliferation was blocked by the FGFR inhibitor (NVP-BGJ398) and various signaling pathway inhibitors, such as Erk1/2 inhibitor (PD98059), PI3K/Akt inhibitor (LY294002), JNK inhibitor (SP600125), and p38MAPK inhibitor (SB203580). The FGFR inhibitor reduced the activation of protein kinases, such as AKT, Erk1/2, JNK, and p38, in several signaling pathways. The downstream kinase of FGFR, Src, was activated by FGF-2, and its activation was canceled by the FGFR inhibitor. MEK1/2, a downstream kinase of Src, was parallelly regulated by FGF-2. The Src inhibitor (PP1) markedly blocked the proliferation of hASCs via inhibition of Src and MEK1/2.
Src activation is indispensable for FGF-2-mediated proliferation of ASCs, as well as the subsequent activation of multi-signaling pathways.
人脂肪来源的干细胞（hASCs）是间充质干细胞（MSCs）的一个亚群；它被认为是最有前途的干细胞之一。我们之前发现成纤维细胞生长因子-2（FGF-2）增强了 hASC 的增殖和分化。然而，FGF-2 促进 hASC 生长的机制尚未得到研究。
用 FGF-2 培养人脂肪来源的干细胞（hASCs），并评估细胞生长情况。研究了成纤维细胞生长因子受体（FGFR）抑制剂（NVP-BGJ398）、ERK1/2 抑制剂（PD98059）、PI3K/Akt 抑制剂（LY294002）、JNK 抑制剂（SP600125）和 p38MAPK 抑制剂（SB203580）以及Src 抑制剂（PP1）对增殖的影响。同时，我们在蛋白水平上评估了 FGFR 抑制剂对 ERK1/2、JNK、p38 和 Akt 等几种信号酶的影响。还检查了 FGF-2 通过 Src 激活的参与情况。
FGF-2 在浓度低于 10ng/ml 时可显著促进 hASC 的增殖，并刺激细胞进入 S 和 G2/M 期。FGFR 抑制剂（NVP-BGJ398）和各种信号通路抑制剂，如 Erk1/2 抑制剂（PD98059）、PI3K/Akt 抑制剂（LY294002）、JNK 抑制剂（SP600125）和 p38MAPK 抑制剂（SB203580），阻断了增殖。FGFR 抑制剂降低了几种信号通路中蛋白激酶如 AKT、Erk1/2、JNK 和 p38 的激活。FGFR 的下游激酶 Src 被 FGF-2 激活，其激活被 FGFR 抑制剂取消。MEK1/2，Src 的下游激酶，也被 FGF-2 平行调节。Src 抑制剂（PP1）通过抑制 Src 和 MEK1/2，显著阻断 hASC 的增殖。
Src 激活对于 FGF-2 介导的 ASCs 增殖以及随后的多信号通路激活是必不可少的。
