miR Let7-IKKε-YAP/TEAD调控胶质瘤恶性进展机制及靶向IKKε抑制剂 的抑瘤作用

Glioma is a refractory intracranial tumor. IKKε is a serine / threonine protein kinase, its overexpression rate in grade III/IV gliomas is up to 85%, and it can promote the proliferation and invasive ability of glioma.To clarify its mechanism, looking for small molecule inhibitors targeting IKK epsilon, is a key step for the transformation research of IKK epsilon. Our previous study published on BBRC found that Let7b/i targeted to IKKε. Meanwhile, the result of immunoprecipitation showed that IKKε can interact with YAP1 and TEAD2. Therefore, we will determine the novel mechanism that miRNA let-7 regulats the proliferative and invasive ability of glioma by targetting to IKKε directly. We will find and confirm that IKKε phosphorylates YAP1（S131）and TEAD2（S335）(new Phosphorylation site), and take part in the phosphorylation cascade control of Hippo signal pathway. Finally, we will study that the anti-glioma effect of targeting inhibitors to IKKε, Amlexanox and CYT387..We expect to elucidate a new molecular regulation mechanism of glioma focusing on IKKε, hope to add the new knowledge to regulation mechanism of Hippo signal pathway in tumor progression, and provide the experimental data for glioma treatment strategies using the inhibitors targeting to IKKε.

恶性胶质瘤是一颅内难治性肿瘤。IKKε是一丝/苏氨酸蛋白激酶，其在III/IV级胶质瘤中高表达率达85%，促进胶质瘤的增殖和侵袭。阐明其机制，寻找靶向IKKε的小分子抑制剂，是针对IKKε进行转化性研究的关键。本课题组发表于BBRC的前期研究发现Let7b/i靶向抑制IKKε；免疫沉淀证实IKKε与YAP1,TEAD相互作用。故本课题拟应用分子生物学方法确定miR let-7靶向IKKε调控胶质瘤细胞增殖和侵袭的新机制；体内外激酶实验发现并证实IKKε磷酸化YAP1（S131）TEAD2（S335）（新磷酸化位点），并通过磷酸化YAP/TEAD参与Hippo通路的磷酸化级联调控新机制；IKKε抑制剂 Amlexanox和CYT387对胶质瘤的治疗研究。将为肿瘤中Hippo通路的调控机制提供崭新的认识。揭示以IKKε为中心的胶质瘤调控的新机制。为靶向IKKε小分子药物治疗胶质瘤奠定基础。

恶性胶质瘤是一颅内难治性肿瘤。IKKε是一丝/苏氨酸蛋白激酶，其在III/IV级胶质瘤中高表达率达85%，促进胶质瘤的增殖和侵袭。阐明其机制，寻找靶向IKKε的小分子抑制剂，是针对IKKε进行转化性研究的关键。本课题组在此基金资助下研究发现：1. IKBKE 通过IKBKE/YAP1/miR-Let-7b/i调控环路促进胶质母细胞瘤的进展；2. IKBKE的选择性抑制剂Amlexanox通过影响人胶质母细胞瘤细胞系中的Hippo途径产生抗肿瘤作用.IKBKE通过促进LATS1 /2降解，下调LATS1 / 2来使Hippo途径失活，Amlexanox通过由IKBKE下调介导的Hippo途径激活抑制GBM细胞的恶性表型。3.CYT387作为IKBKE抑制剂通过激活Hippo通路抑制胶质母细胞瘤恶性进展。4.IKBKE通过Hippo信号通路调控人类恶性胶质瘤的细胞增殖和上皮-间质转化。此外，研究提示IKKε可能通过磷酸化Amotl2（S166），上调Amotl2表达。为以后的有关IKKε调控胶质母细胞瘤的恶性进展的机制研究提供了新线索。揭示以IKKε为中心的胶质瘤调控的新机制。为靶向IKKε小分子药物治疗胶质瘤奠定基础。