Wang Cheng, Song Rui, Yuan Jinjin, Hou Ge, Chu A Lan, Huang Yangyang, Xiao Chenhu, Chai Ting, Sun Chen, Liu Zongwen
Department of Radiation Oncology, the Second Affiliated Hospital of Zhengzhou University, Zhengzhou City, Henan Province, China.
Drug Dev Res. 2025 Feb;86(1):e70025. doi: 10.1002/ddr.70025.
Acute myelogenous leukemia (AML)-derived mesenchymal stem cells (MSCs) (AML-MSCs) have been identified to play a significant role in AML progression. The functions of MSCs mainly depend on their paracrine action. Here, we investigated whether AML-MSCs functioned in AML cells by transferring METTL14 (Methyltransferase 14) into AML cells via exosomes. Functional analyses were conducted using MTT assay, 5-ethynyl-2-deoxyuridine assay and flow cytometry. qRT-PCR and western blot analyses detected levels of mRNAs and proteins. Exosomes (exo) were isolated from AML-MSCs by ultracentrifugation. The m6A modification profile was determined by methylated RNA immunoprecipitation (MeRIP) assay. The interaction between Insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3) and Rho Kinase 1 (ROCK1) was validated using RIP assay. AML-MSCs incubation promoted the proliferation and radioresistance in AML cells. Moreover, AML-MSCs incubation led to increases in m6A levels and METTL14 levels in AML cells. METTL14 was transferred into AML cells by packaging into exosomes of AML-MSCs. The knockdown of METTL14 in AML-MSCs exosomes could reduce the proliferation and radioresistance in AML cells. Mechanistically, METTL14 induced ROCK1 m6A modification and stabilized its expression by an m6A-IGF2BP3-dependent mechanism. Rescue assay showed that ROCK1 overexpression reversed the inhibitory effects of METTL14 silencing in AML-MSCs exosomes on AML cell proliferation and radioresistance. Exosome-shuttled METTL14 from AML-MSCs promoted proliferation and conferred radioresistance in AML cells by stabilizing ROCK1 expression via an m6A-IGF2BP3-dependent mechanism.
急性髓系白血病（AML）来源的间充质干细胞（MSCs）（AML-MSCs）已被证实在AML进展中发挥重要作用。MSCs的功能主要依赖于其旁分泌作用。在此，我们研究了AML-MSCs是否通过外泌体将METTL14（甲基转移酶14）转移至AML细胞中从而发挥作用。使用MTT法、5-乙炔基-2'-脱氧尿苷法和流式细胞术进行功能分析。qRT-PCR和蛋白质印迹分析检测mRNA和蛋白质水平。通过超速离心从AML-MSCs中分离出外泌体（exo）。通过甲基化RNA免疫沉淀（MeRIP）测定法确定m6A修饰谱。使用RNA免疫沉淀（RIP）测定法验证胰岛素样生长因子2 mRNA结合蛋白3（IGF2BP3）与Rho激酶1（ROCK1）之间的相互作用。AML-MSCs孵育可促进AML细胞的增殖和放射抗性。此外，AML-MSCs孵育导致AML细胞中m6A水平和METTL14水平升高。METTL14通过包装到AML-MSCs的外泌体中转移至AML细胞。敲低AML-MSCs外泌体中的METTL14可降低AML细胞的增殖和放射抗性。机制上，METTL14通过m6A-IGF2BP3依赖性机制诱导ROCK1的m6A修饰并稳定其表达。拯救实验表明，ROCK1过表达可逆转AML-MSCs外泌体中METTL14沉默对AML细胞增殖和放射抗性的抑制作用。AML-MSCs中外泌体穿梭的METTL14通过m6A-IGF2BP3依赖性机制稳定ROCK1表达，从而促进AML细胞增殖并赋予其放射抗性。
