Department of Hematology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
Hematol Oncol. 2021 Aug;39(3):390-400. doi: 10.1002/hon.2874. Epub 2021 May 10.
The exosomes are involved in intercellular communication via RNA trafficking in human diseases. Hsa_circ_0009910 (circ_0009910) is a novel leukemia-related circular RNA. However, the mechanism of circ_0009910 in acute myeloid leukemia (AML) cell-to-cell communication remained obscure. Expression of circ_0009910, miRNA (miR)-5195-3p and growth factor receptor-bound protein 10 (GRB10) was detected by quantitative real-time polymerase chain reaction and Western blotting. A stable cell coculture model was established and functional experiment was performed using Cell Counting Kit-8 assay, flow cytometry, and Western blotting. The interaction among circ_0009910, miR-5195-3p and GRB10 was confirmed by dual-luciferase reporter assay and RNA immunoprecipitation. As a result, circ_0009910 was upregulated in AML bone marrows and cells (HL-60 and MOLM-13), even higher in AML cells-derived exosomes. Functionally, blocking circ_0009910 via small interfering RNA (siRNA) suppressed cell proliferation and cell cycle progression, but facilitated apoptosis rate of HL-60 and MOLM-13 cells, accompanied with lower B-cell lymphoma 2 (Bcl-2) level and higher Bcl-2-associated X protein (Bax) level. circ_0009910 shuttled via exosomes negatively regulated miR-5195-3p expression by target binding. Furthermore, circ_0009910 knockdown via exosomes and miR-5195-3p overexpression via mimic resulted in similar results of circ_0009910 siRNA in proliferation, apoptosis and cell cycle progression of AML cells. Meanwhile, the role of circ_0009910 knockdown in AML cells was partially reversed by miR-5195-3p deletion, and restoring GRB10 could abrogate miR-5195-3p effect as well. Notably, GRB10 was a downstream target of miR-5195-3p. circ_0009910-containing exosomes mediated proliferation, apoptosis and cell cycle progression of AML cells partially through miR-5195-3p/GRB10 axis.
外泌体通过 RNA 转运参与人类疾病中的细胞间通讯。Hsa_circ_0009910（circ_0009910）是一种新型的白血病相关环状 RNA。然而，circ_0009910 在急性髓系白血病（AML）细胞间通讯中的机制尚不清楚。通过实时定量聚合酶链反应和 Western blot 检测 circ_0009910、miRNA（miR）-5195-3p 和生长因子受体结合蛋白 10（GRB10）的表达。建立稳定的细胞共培养模型，并通过细胞计数试剂盒-8 测定、流式细胞术和 Western blot 进行功能实验。通过双荧光素酶报告基因检测和 RNA 免疫沉淀证实了 circ_0009910、miR-5195-3p 和 GRB10 之间的相互作用。结果显示，circ_0009910 在 AML 骨髓和细胞（HL-60 和 MOLM-13）中上调，甚至在 AML 细胞来源的外泌体中上调更高。功能上，通过小干扰 RNA（siRNA）阻断 circ_0009910 抑制 HL-60 和 MOLM-13 细胞的增殖和细胞周期进程，但促进细胞凋亡，同时降低 B 细胞淋巴瘤 2（Bcl-2）水平，增加 Bcl-2 相关 X 蛋白（Bax）水平。circ_0009910 通过外泌体穿梭，通过靶标结合负调控 miR-5195-3p 的表达。此外，通过外泌体敲低 circ_0009910 和通过模拟物过表达 miR-5195-3p 导致 AML 细胞增殖、凋亡和细胞周期进程的结果与 circ_0009910 siRNA 相似。同时，miR-5195-3p 缺失部分逆转了 circ_0009910 敲低在 AML 细胞中的作用，而恢复 GRB10 也可以消除 miR-5195-3p 的作用。值得注意的是，GRB10 是 miR-5195-3p 的下游靶标。含有 circ_0009910 的外泌体通过 miR-5195-3p/GRB10 轴部分介导 AML 细胞的增殖、凋亡和细胞周期进程。
