School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China.
State Key Laboratory of Ophthalmology, Optometry and Visual Science, Wenzhou, Zhejiang, China.
J Cell Physiol. 2020 Oct;235(10):7107-7119. doi: 10.1002/jcp.29608. Epub 2020 Feb 4.
N -methyladenosine (m A) is a novel epitranscriptomic marker that contributes to regulating diverse biological processes through controlling messenger RNA metabolism. However, it is unknown if m A RNA methylation affects uveal melanoma (UM) development. To address this question, we probed its function and molecular mechanism in UM. Initially, we demonstrated that global RNA m A methylation levels were dramatically elevated in both UM cell lines and clinical specimens. Meanwhile, we found that METTL3, a main m A regulatory enzyme, was significantly increased in UM cells and specimens. Subsequently, cycloleucine (Cyc) or METTL3 targeted small interfering RNA was used to block m A methylation in UM cells. We found that Cyc or silencing METTL3 significantly suppressed UM cell proliferation and colony formation through cell cycle G1 arrest, as well as migration and invasion by functional analysis. On the other hand, overexpression of METTL3 had the opposite effects. Furthermore, bioinformatics and methylated RNA immunoprecipitation-quantitative polymerase chain reaction identified c-Met as a direct target of m A methylation in UM cells. In addition, western blot analysis showed that Cyc or knockdown of METTL3 downregulated c-Met, p-Akt, and cell cycle-related protein levels in UM cells. Taken together, our results demonstrate that METTL3-mediated m A RNA methylation modulates UM cell proliferation, migration, and invasion by targeting c-Met. Such a modification acts as a critical oncogenic regulator in UM development.
N6-甲基腺苷(m6A)是一种新型的转录后修饰标记物,通过控制信使 RNA 代谢,调节多种生物学过程。然而,m6A RNA 甲基化是否影响葡萄膜黑色素瘤(UM)的发展尚不清楚。为了解决这个问题,我们研究了其在 UM 中的功能和分子机制。首先,我们证明了 UM 细胞系和临床标本中的总 RNA m6A 甲基化水平显著升高。同时,我们发现 METTL3,一种主要的 m6A 调节酶,在 UM 细胞中显著增加。随后,使用环亮氨酸(Cyc)或 METTL3 靶向的小干扰 RNA 阻断 UM 细胞中的 m6A 甲基化。通过细胞周期 G1 期阻滞、迁移和侵袭功能分析,我们发现 Cyc 或沉默 METTL3 显著抑制 UM 细胞增殖和集落形成。另一方面,过表达 METTL3 则产生相反的效果。此外,生物信息学和甲基化 RNA 免疫沉淀-定量聚合酶链反应鉴定出 c-Met 是 UM 细胞中 m6A 甲基化的直接靶标。此外,Western blot 分析表明,Cyc 或 METTL3 敲低降低了 UM 细胞中 c-Met、p-Akt 和细胞周期相关蛋白的水平。总之,我们的结果表明,METTL3 介导的 m6A RNA 甲基化通过靶向 c-Met 调节 UM 细胞的增殖、迁移和侵袭。这种修饰在 UM 发展中充当关键的致癌调节因子。