Differentiation-inducing factor-1 induces cyclin D1 degradation through the phosphorylation of Thr286 in squamous cell carcinoma
Differentiation-inducing factor-1 induces cyclin D1 degradation through the phosphorylation of Thr286 in squamous cell carcinoma
复制标题
DOI：
10.1016/j.yexcr.2005.07.024
复制
发表时间：
2005-11-01
影响因子：
3.7
通讯作者：
Sasaguri, T
中科院分区：
文献类型：
--
作者：
Mori, J;Takahashi-Yanaga, F;Sasaguri, T
分化诱导因子（DIF）是诱导网骨藻细胞分化的形态发生素。我们报道了DIF-1和DIF-3抑制哺乳动物细胞的增殖并诱导分化。在这项研究中，我们研究了DIF-1对口腔鳞状细胞癌细胞系NA和SAS的作用，分别是高分化和低分化细胞系。虽然DIF-1不能诱导这些细胞系中细胞分化标志物的表达，但它通过将细胞周期限制在G（0）/G（1）期而以剂量依赖方式抑制NA和SAS的增殖。DIF-1诱导细胞周期蛋白D1降解，但这种作用被氯化锂和S13216763（糖原合成酶激酶-3 β（GSK-3 β）抑制剂）阻止。通过RNA干扰消除内源性GSK-3 β也减弱了DIF-1对细胞周期蛋白D1降解的影响。因此，我们研究了DIF-1对GSK-3 β的作用，发现DIF-1在Set（9）上使GSK-3 β去磷酸化并诱导GSK-3 β的核转位，表明DIF-1激活GSK-3 β。然后，我们检测了DIF-1对细胞周期蛋白D1突变体（Thr 286 Ala、Thr 288 Ala和Thr 286/288 Ala）的作用。我们发现Thr 286 Ala和Thr 286/288 Ala突变体对DIF-1诱导的细胞周期蛋白D1降解具有高度抗性，表明Thr（286）的磷酸化对于DIF-1诱导的细胞周期蛋白D1降解至关重要。这些结果表明，DIF-1通过GSK-3 β介导的Thr磷酸化诱导细胞周期蛋白D1降解（286）。(c)2005年爱思唯尔公司All rights reserved.
Differentiation-inducing factors (DIFs) are morphogens which induce cell differentiation in Dictyostelium. We reported that DIF-1 and DIF-3 inhibit proliferation and induce differentiation in mammalian cells. In this study, we investigated the effect of DIF-1 on oral squamous cell carcinoma cell lines NA and SAS, well differentiated and poorly differentiated cell lines, respectively. Although DIF-1 did not induce the expression of cell differentiation makers in these cell lines, it inhibited the proliferation of NA and SAS in a dose-dependent manner by restricting the cell cycle in the G(0)/G(1) phase. DIF-1 induced cyclin D1 degradation, but this effect was prevented by treatment with lithium chloride and S13216763, the inhibitors of glycogen synthase kinase-3 beta (GSK-3 beta). Depletion of endogenous GSK-3 beta by RNA interference also attenuated the effect of DIF-1 on cyclin D1 degradation. Therefore, we investigated the effect of DIF-1 on GSK-3 beta and found that DIF-1 dephosphorylated GSK-3 beta on Set(9) and induced the nuclear translocation of GSK-3 beta suggesting that DIF-1 activated GSK-3 beta, Then, we examined the effect of DIF-1 on cyclin D1 mutants (Thr286Ala, Thr288Ala, and Thr286/288Ala). We revealed that Thr286Ala and Thr286/288Ala mutants were highly resistant to DIF-1-induced degradation compared with wild-type cyclin D1, indicating that the phosphorylation of Thr(286) was critical for cyclin D1 degradation induced by DIF-1. These results suggest that DIF-1 induces degradation of cyclin D1 through the GSK-3 beta-mediated phosphorylation of Thr(286). (c) 2005 Elsevier Inc. All rights reserved.