酪氨酸磷酸酶PTPRO通过PAK1调节糖酵解关键酶PFK-L抑制肿瘤转移的机制

糖代谢异常对肿瘤转移起重要作用，但机制不明。前期在乳腺癌模式小鼠中发现基因敲除酪氨酸酶PTPRO促进肺转移，转录组学发现PTPRO敲除后糖酵解关键酶PFK-L升高，细胞实验提示PFK-L可介导PTPRO对转移的调控。双分子荧光互补实验表明PTPRO与PAK1结合，动物和临床标本发现PTPRO水平与PAK1酪氨酸磷酸化及细胞核表达相关，而PAK1入核后可参与调控PFK-L转录。假说：PTPRO通过PAK1调节糖酵解关键酶PFK-L，进而调控肿瘤转移。本研究拟①应用细胞和小鼠模型，结合临床标本及生物信息，证明PTPRO-PFK-L是调控能量代谢和肿瘤转移的关键通路；②在体外和体内水平，验证PAK1介导PTPRO调控PFK-L；③在分子水平探讨PAK1酪氨酸磷酸化和细胞核转位是介导PTPRO调控PFK-L转录的关键机制。课题旨在探讨调控肿瘤糖代谢-转移通路的分子机制，为治疗转移提供新思路。

Glucose metabolism deregulation in cancer cells contributes to metastasis. However, the underlying mechanism is unclear. Our preliminary data showed that Ptpro deficiency in mice facilitates lung metastasis of MMTV-pyMT-induced mammary tumorigenesis, and transcriptomic profiling indicated that loss of PTPRO lead to upregulation of key glycolytic enzyme phosphofructokinase-liver isoform (PFK-L). Bimolecular fluorescence complementation (BiFC) assay revealed that PTPRO can interact with p21 protein (Cdc42/Rac)-activated kinase 1 (PAK1). Analysis of mouse model and patient specimen showed that PTPRO expression was closely associated with PAK1 tyrosine phosphorylation and nuclear localization, which subsequently regulate transcription of PFK-L. We hypothesize that PTPRO represses tumor metastasis by regulating key glycolytic enzyme PFK-L in a PAK1 dependent manner. We thus propose to clarify whether PTPRO regulates metastasis via glucose metabolism using mouse model, cultured cells, patient specimen and bioinformatic data mining. Second, we will verify whether PAK1 mediates PTPRO's regulation on PFK-L. Third, we will elucidate that tyrosine phosphorylation of PAK1 and its translocation into nucleus are the key mechanisms for PTPRO-induced PFK-L alteration. The study is of importance for the insight of regulatory mechanism on glucose metabolism deregulation-induced metastasis. The finding will benefit designing the novel strategy for anti-metastasis therapeutics.