PHF20通过WTAP调控胶质母细胞瘤干性的表观遗传学机制和应用研究

Glioblastoma (GBM) is the most malignant form of glioma, with poorly differentiated and highly pluripotency. The clinical treatment of GBM remains unsatisfactory. All of which leads to the burning question: how to inhibit pluripotency of GBM efficiently? Our published work identified a series of key factors driving maintenance of neuro-oncology stem cells, including epigenetic factor PHF20. Recently we found the expression of PHF20 negatively correlated with GBM patients’ outcome and knock-out PHF20 can significantly decreased the proportion of GBM stem cells and down-regulated the stemness genes. Importantly, we found PHF20 can interact with WTAP, the component of m6A transmethylase and screened PHF20 inhibitor OICR-9429.Therefore, we hypothesis that PHF20 collaborate with WTAP to promote pluripotency of glioblastoma and OICR-9429 will bring therapeutic effects in GBM treatment. To test our hypothesis, we will use RNA-seq, ChIP-seq and MeRIP-seq to explore correlation of the epigenetics regulation, m6A methylation and downstream genes of PHF20-WTAP axis. Besides, we will further clarify the therapeutic effects of PHF20 inhibitor OICR-9429 for GSCs in animal model. In a word, our study will reveal the epigenetics mechanism of PHF20 in glioblastoma pluripotency, which is of great importance for identifying new drugs and promoting GBM therapy.

胶质母细胞瘤(GBM)是恶性程度最高的胶质瘤，具有分化程度低和干性强的特点，临床上治疗难度极大。因此，如何抑制GBM干性是亟待解决的问题。申请人已发表的工作鉴定出一系列维持神经肿瘤干性的关键因子，包括表观遗传因子PHF20。最近研究又发现PHF20的表达与GBM临床预后呈负相关，敲除PHF20可下调GBM干细胞比例和干性基因表达。并筛选出PHF20抑制剂OICR-9429以及发现PHF20可与m6A甲基转移酶复合体成分WTAP结合。据此我们提出科学假设：PHF20通过WTAP调控GBM干性，用PHF20抑制剂可抑制GBM干性从而起治疗效果。本项目拟采用RNA-seq、ChIP-seq和MeRIP-seq探究PHF20-WTAP轴调控表观遗传标记、m6A甲基化与基因表达的关系,并探索PHF20抑制剂对GBM的治疗价值。本研究对进一步揭示GBM干性的表观遗传学机制与研发GBM新药具有重要意义。

胶质母细胞瘤(GBM)是恶性程度最高的胶质瘤，具有分化程度低和干性强的特点，临床上治疗难度极大。因此，如何抑制GBM干性是亟待解决的问题。申请人已发表的工作鉴定出一系列维持神经肿瘤干性的关键因子，包括表观遗传因子PHF20。本项目旨在探究PHF20在GBM中的作用并阐明其表观遗传调控机制。结果发现PHF20高表达于胶质瘤临床标本中，且PHF20的表达与GBM干性和临床预后紧密相关。敲除或敲降PHF20可显著下调GBM干细胞比例和干性基因表达，并抑制GBM细胞增殖、侵袭和小鼠体内成瘤。通过高通量测序筛选出PHF20的关键下游基因WISP1和BGN，二者形成异二聚体。PHF20通过与WDR5相互作用结合在WISP1启动子区域，提高WISP1和BGN复合物的表达，后者进一步调控β-Catenin的降解，促进GBM恶性进展。本研究证实PHF20作为维持GBM干性的关键表观遗传因子，对进一步揭示GBM重编程的表观遗传学调控机制，设计针对GBM干细胞的新治疗靶点和制定新治疗策略，改善GBM的疗效具有积极意义。