Li Li, Wan Dingming, Li Lin, Qin Yang, Ma Wang
Department of Hematology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou City, Henan Province 450052, People's Republic of China.
Department of Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou City, Henan Province 450052, People's Republic of China.
Onco Targets Ther. 2021 Jan 18;14:531-544. doi: 10.2147/OTT.S291123. eCollection 2021.
Although long non-coding RNA (lncRNA) RAET1K has been observed to be abnormally expressed in patients with various cancers, its role and molecular mechanism in acute myeloid leukemia (AML) remain unclear.
The expression of RAET1K and miR-503-5p in bone marrow tissues and cell lines was detected by qRT-PCR. Cell proliferation was evaluated by cell counting kit-8 and 5-ethynyl-20-deoxyuridine (EdU) staining assay. Cell invasion and migration were detected by transwell assay. Cell apoptosis was evaluated by flow cytometry. The relationship between RAET1K and miR-503-5p, as well as miR-503-5p and INPP4B, was determined by luciferase reporter assay and RNA immunoprecipitation (RIP) assay. In addition, the tumorigenesis of leukemia cells was evaluated by using a xenograft mouse model in vivo.
RAET1K was significantly upregulated and miR-503-5p was markedly downregulated in bone marrow tissues and cell lines (HL-60 and THP-1). Silencing of RAET1K (si-RAET1K) and overexpression of miR-503-5p inhibited cell proliferation, migration, and invasion but promoted apoptosis of HL-60 and THP-1 cells. RAET1K functioned as a sponge of miR-503-5p, and miR-503-5p inhibitor obviously attenuated the effect of si-RAET1K on AML progression in vitro. INPP4B was identified as a target of miR-503-5p, and INPP4B overexpression obviously reversed the effect of miR-503-5p mimics on cell proliferation, migration, invasion, and apoptosis of HL-60 and THP-1 cells in vitro. Knockdown of RAET1K effectively inhibited the tumorigenesis of leukemia cells in vivo.
Our results demonstrated that RAET1K/miR-503-5p/INPP4B axis contributed to AML progression, suggesting that RAET1K might be a potential target for the treatment of AML.
尽管已观察到长链非编码RNA（lncRNA）RAET1K在多种癌症患者中异常表达，但其在急性髓系白血病（AML）中的作用和分子机制仍不清楚。
采用qRT-PCR检测骨髓组织和细胞系中RAET1K和miR-503-5p的表达。通过细胞计数试剂盒-8和5-乙炔基-2'-脱氧尿苷（EdU）染色试验评估细胞增殖。采用Transwell试验检测细胞侵袭和迁移。通过流式细胞术评估细胞凋亡。通过荧光素酶报告基因试验和RNA免疫沉淀（RIP）试验确定RAET1K与miR-503-5p以及miR-503-5p与INPP4B之间的关系。此外，通过体内异种移植小鼠模型评估白血病细胞的肿瘤发生情况。
RAET1K在骨髓组织和细胞系（HL-60和THP-1）中显著上调，而miR-503-5p明显下调。沉默RAET1K（si-RAET1K）和过表达miR-503-5p可抑制HL-60和THP-1细胞的增殖、迁移和侵袭，但促进其凋亡。RAET1K作为miR-503-5p的海绵，miR-503-5p抑制剂明显减弱了si-RAET1K对体外AML进展的影响。INPP4B被鉴定为miR-503-5p的靶标，INPP4B过表达明显逆转了miR-503-5p模拟物对体外HL-60和THP-1细胞增殖、迁移、侵袭和凋亡的影响。敲低RAET1K可有效抑制体内白血病细胞的肿瘤发生。
我们的结果表明，RAET1K/miR-503-5p/INPP4B轴促进了AML的进展，提示RAET1K可能是治疗AML的潜在靶点。
