CDK5在胰腺癌细胞中对Notch1信号转导的调控

Striking overexpressions of CDK5 and Notch1 receptor, which play critical roles during pancreatic cancer development and are promising therapeutic targets, are detectable in vast majority pancreatic cancer cell lines and tissues. However, the relationship between CDK5 and Notch1 and the role of this relationship in the development of pancreatic cancer remain unclear. Our previous results demonstrated that CDK5 interacts physically with Notch1 and phosphorylates Notch1 peptide. That indicates CDK5 may regulate Notch signaling through phosphorylation and further play roles in pancreatic cancer cells proliferation and invasion. In this proposal, we will directly examine whether Notch1 is a novel substrate of CDK5 and detect the effect of phosphorylation by CDK5 on Notch signaling, using methods such as in vitro kinase assay, liquid chromatography tandem (LC-Ms/Ms), mutagenesis and dual luciferase assay. We aim to evaluate the role of S/T phosphorylation by CDK5 on modulation of Notch signaling and that in pancreatic cancer development and provide novel experimental therapeutic strategy against pancreatic cancer.

CDK5和Notch1受体在胰腺癌组织中均过表达，并促进胰腺癌细胞的生长和迁移，二者均是抗肿瘤药物研发的热门靶点，但二者间的相互关系及其在胰腺癌细胞恶性行为中的作用尚未见报道。我们前期研究发现CDK5和Notch1间存在着生理上的相互作用；CDK5可以对Notch1小肽进行磷酸化修饰。因此我们假设CDK5通过磷酸化Notch1来调控Notch1信号转导，进而影响胰腺癌细胞的增殖和迁移。本项目拟采用体外磷酸化实验、串联液相质谱方法、点突变和报告基因系统分析等方法，验证CDK5可以磷酸化修饰Notch1，阐明这种修饰在Notch1受体成熟、信号转导及胰腺癌细胞增殖和迁移中的作用。本课题通过探索CDK5作为磷酸激酶调控Notch1信号通路在胰腺癌进展中的作用，不仅鉴定了新的Notch1信号的调控因素，而且为胰腺癌提供新的实验性治疗思路。

CDK5和Notch1受体在胰腺癌组织中均过表达，并促进胰腺癌细胞的生长和迁移，二者均是抗肿瘤药物研发的热门靶点，但二者间的相互关系及其在胰腺癌细胞恶性行为中的作用尚未见报道。本项目采用体外磷酸化实验、串联液相质谱方法、点突变和报告基因系统分析等方法，证明了CDK5和Notch1间存在着生理上的相互作用；CDK5可以对Notch1小肽进行磷酸化修饰；CDK5通过磷酸化Notch1来调控Notch1信号转导，进而影响胰腺癌细胞的增殖和迁移。本课题通过探索CDK5作为磷酸激酶调控Notch1信号通路在胰腺癌进展中的作用，不仅鉴定了新的Notch1信号的调控因素，而且为胰腺癌提供新的实验性治疗思路。