Barrett Angela, Evans Ian M, Frolov Antonina, Britton Gary, Pellet-Many Caroline, Yamaji Maiko, Mehta Vedanta, Bandopadhyay Rina, Li Ningning, Brandner Sebastian, Zachary Ian C, Frankel Paul
Centre for Cardiovascular Biology and Medicine, Division of Medicine, Rayne Building, University College London, London WC1E 6JJ, UK.
Reta Lila Weston Institute of Neurological Studies.
J Cell Sci. 2014 Jun 15;127(Pt 12):2647-58. doi: 10.1242/jcs.135988. Epub 2014 Apr 24.
DOK1 regulates platelet-derived growth factor (PDGF)-BB-stimulated glioma cell motility. Mechanisms regulating tumour cell motility are essential for invasion and metastasis. We report here that PDGF-BB-mediated glioma cell invasion and migration are dependent on the adaptor protein downstream of kinase 1 (DOK1). DOK1 is expressed in several glioma cell lines and in tumour biopsies from high-grade gliomas. DOK1 becomes tyrosine phosphorylated upon PDGF-BB stimulation of human glioma cells. Knockdown of DOK1 or expression of a DOK1 mutant (DOK1FF) containing Phe in place of Tyr at residues 362 and 398, resulted in inhibition of both the PDGF-BB-induced tyrosine phosphorylation of p130Cas (also known as BCAR1) and the activation of Rap1. DOK1 colocalises with tyrosine phosphorylated p130Cas at the cell membrane of PDGF-BB-treated cells. Expression of a non-tyrosine-phosphorylatable substrate domain mutant of p130Cas (p130Cas15F) inhibited PDGF-BB-mediated Rap1 activation. Knockdown of DOK1 and Rap1 inhibited PDGF-BB-induced chemotactic cell migration, and knockdown of DOK1 and Rap1 and expression of DOK1FF inhibited PDGF-mediated three-dimensional (3D) spheroid invasion. These data show a crucial role for DOK1 in the regulation of PDGF-BB-mediated tumour cell motility through a p130Cas-Rap1 signalling pathway. [Corrected]
DOK1调节血小板衍生生长因子（PDGF）-BB刺激的胶质瘤细胞运动。调节肿瘤细胞运动的机制对于侵袭和转移至关重要。我们在此报告，PDGF-BB介导的胶质瘤细胞侵袭和迁移依赖于激酶1下游的衔接蛋白（DOK1）。DOK1在几种胶质瘤细胞系以及高级别胶质瘤的肿瘤活检组织中表达。在人胶质瘤细胞受到PDGF-BB刺激后，DOK1会发生酪氨酸磷酸化。敲低DOK1或表达在362和398位残基处用苯丙氨酸取代酪氨酸的DOK1突变体（DOK1FF），会导致PDGF-BB诱导的p130Cas（也称为BCAR1）酪氨酸磷酸化以及Rap1激活均受到抑制。在PDGF-BB处理的细胞的细胞膜上，DOK1与酪氨酸磷酸化的p130Cas共定位。p130Cas的非酪氨酸磷酸化底物结构域突变体（p130Cas15F）的表达抑制了PDGF-BB介导的Rap1激活。敲低DOK1和Rap1抑制了PDGF-BB诱导的趋化性细胞迁移，敲低DOK1和Rap1以及表达DOK1FF抑制了PDGF介导的三维（3D）球体侵袭。这些数据表明DOK1在通过p130Cas-Rap1信号通路调节PDGF-BB介导的肿瘤细胞运动中起关键作用。[已校正]
