Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
Clinical Medical Research Center of Hepatic Surgery at Hubei Province, Wuhan, 430030, China.
Adv Sci (Weinh). 2024 Apr;11(13):e2307242. doi: 10.1002/advs.202307242. Epub 2024 Jan 21.
N6-methyladenosine (mA) modification orchestrates cancer formation and progression by affecting the tumor microenvironment (TME). For hepatocellular carcinoma (HCC), immune evasion and angiogenesis are characteristic features of its TME. The role of YTH N6-methyladenosine RNA binding protein 2 (YTHDF2), as an mA reader, in regulating HCC TME are not fully understood. Herein, it is discovered that trimethylated histone H3 lysine 4 and H3 lysine 27 acetylation modification in the promoter region of YTHDF2 enhanced its expression in HCC, and upregulated YTHDF2 in HCC predicted a worse prognosis. Animal experiments demonstrated that Ythdf2 depletion inhibited spontaneous HCC formation, while its overexpression promoted xenografted HCC progression. Mechanistically, YTHDF2 recognized the mA modification in the 5'-untranslational region of ETS variant transcription factor 5 (ETV5) mRNA and recruited eukaryotic translation initiation factor 3 subunit B to facilitate its translation. Elevated ETV5 expression induced the transcription of programmed death ligand-1 and vascular endothelial growth factor A, thereby promoting HCC immune evasion and angiogenesis. Targeting YTHDF2 via small interference RNA-containing aptamer/liposomes successfully both inhibited HCC immune evasion and angiogenesis. Together, this findings reveal the potential application of YTHDF2 in HCC prognosis and targeted treatment.
N6-甲基腺苷(mA)修饰通过影响肿瘤微环境(TME)来调控癌症的发生和进展。对于肝细胞癌(HCC),免疫逃逸和血管生成是其 TME 的特征性特征。YTH N6-甲基腺苷 RNA 结合蛋白 2(YTHDF2)作为 mA 阅读器,在调节 HCC TME 中的作用尚未完全阐明。在此,发现 YTHDF2 启动子区域的组蛋白 H3 赖氨酸 4 三甲基化和 H3 赖氨酸 27 乙酰化修饰增强了其在 HCC 中的表达,并上调了 HCC 中的 YTHDF2,预示着预后更差。动物实验表明,Ythdf2 耗竭抑制自发性 HCC 形成,而过表达则促进异种移植 HCC 进展。机制上,YTHDF2 识别 ETS 变体转录因子 5(ETV5)mRNA 5'-非翻译区的 mA 修饰,并募集真核翻译起始因子 3 亚基 B 促进其翻译。升高的 ETV5 表达诱导程序性死亡配体 1 和血管内皮生长因子 A 的转录,从而促进 HCC 的免疫逃逸和血管生成。通过包含小干扰 RNA 的适体/脂质体靶向 YTHDF2 成功地抑制了 HCC 的免疫逃逸和血管生成。总之,这些发现揭示了 YTHDF2 在 HCC 预后和靶向治疗中的潜在应用。