School of Biosystems and Biomedical Sciences, College of Health Sciences, Korea University, Seoul 02841, Korea.
Center for Functional Connectomics, KIST, Seoul 02792, Korea.
Cells. 2020 Apr 26;9(5):1079. doi: 10.3390/cells9051079.
ANO1, a Ca-activated chloride channel, is highly expressed in glioblastoma cells and its surface expression is involved in their migration and invasion. However, the regulation of ANO1 surface expression in glioblastoma cells is largely unknown. In this study, we found that Ca/Calmodulin-dependent protein kinase II (CaMKII) β specifically enhances the surface expression and channel activity of ANO1 in U251 glioblastoma cells. When KN-93, a CaMKII inhibitor, was used to treat U251 cells, the surface expression and channel activity of ANO1 were significantly reduced. Only CaMKIIβ, among the four CaMKII isoforms, increased the surface expression and channel activity of ANO1 in a heterologous expression system. Additionally, gene silencing of CaMKIIβ suppressed the surface expression and channel activity of ANO1 in U251 cells. Moreover, gene silencing of CaMKIIβ or ANO1 prominently reduced the migration and invasion of U251 and U87 MG glioblastoma cells. We thus conclude that CaMKIIβ plays a specific role in the surface expression of ANO1 and in the ANO1-mediated tumorigenic properties of glioblastoma cells, such as migration and invasion.
ANO1 是一种钙激活氯离子通道，在神经胶质瘤细胞中高度表达，其表面表达参与了细胞的迁移和侵袭。然而，AN01 在神经胶质瘤细胞表面表达的调控机制在很大程度上仍是未知的。在本研究中，我们发现钙/钙调蛋白依赖性蛋白激酶 II（CaMKII）β 特异性增强了 U251 神经胶质瘤细胞中 AN01 的表面表达和通道活性。当使用 CaMKII 抑制剂 KN-93 处理 U251 细胞时，ANO1 的表面表达和通道活性显著降低。在异源表达系统中，只有 CaMKIIβ 这一种 CaMKII 同工型增加了 AN01 的表面表达和通道活性。此外，CaMKIIβ 的基因沉默抑制了 U251 细胞中 AN01 的表面表达和通道活性。此外，CaMKIIβ 或 AN01 的基因沉默显著降低了 U251 和 U87MG 神经胶质瘤细胞的迁移和侵袭。因此，我们得出结论，CaMKIIβ 在 AN01 的表面表达和 AN01 介导的神经胶质瘤细胞的致瘤特性（如迁移和侵袭）中发挥特异性作用。
