MiR-204 suppresses the progression of acute myeloid leukemia through HGF/c-Met pathway

Acute myeloid leukemia (AML) was confirmed to be associated with hematopoietic insufficiency, as well as abnormal proliferation, differentiation or survival of myeloid progenitors. Multiple studies reported that microRNA-204 (miR-204) and Hepatocyte growth factor (HGF) played important roles in types of cancers. However, the potential molecular regulatory mechanism between miR-204 and HGF in AML remains to be further defined. Real-time PCR (RT-PCR) was adopted to detect the expression of miR-204 and HG. Relative protein levels were detected by western blot assay. The viability, cell cycle, apoptosis, migration, and invasion were analyzed by MTT, flow cytometry, and transwell assays. Moreover, the target relationship between miR-204 and HGF was predicted by MiRcode website and confirmed by luciferase reporter, RNA pull-down, and western blot assays. Our data suggested that miR-204 was downregulated in AML serum samples and cells. MiR-204 overexpression repressed cell proliferation, migration, invasion, and induced cell apoptosis in AML cells. HGF was upregulated in AML samples and cells, and HGF knockdown inhibited the malignancy of AML cells. In addition, HGF was directly targeted by miR-204. HGF overexpression reversed the effects of miR-204 mimic on AML cell proliferation, apoptosis, migration, and invasion. Besides, miR-204 regulated the c-Met signaling by targeting HGF, thereby regulating the downstream protein levels related to cell proliferation, apoptosis, migration, and invasion in AML cells. In conclusion, miR-204 could regulate AML progression through regulating the HGF/c-Met pathway.

急性髓系白血病（Acute myeloid leukemia, AML）现已证实与造血功能不全、髓系祖细胞异常增殖、分化或存活异常密切相关。多项研究表明，微小RNA-204（microRNA-204, miR-204）与肝细胞生长因子（Hepatocyte growth factor, HGF）在多种癌症中发挥关键调控作用。然而，miR-204与HGF在AML中的潜在分子调控机制仍有待进一步阐明。本研究采用实时荧光定量PCR（Real-time PCR, RT-PCR）检测miR-204与HGF的表达水平，通过蛋白质印迹（Western blot）实验检测相关蛋白的相对表达量。采用MTT法、流式细胞术及Transwell实验分别分析细胞活力、细胞周期、凋亡、迁移及侵袭能力。此外，通过MiRcode数据库预测了miR-204与HGF的靶向结合关系，并经荧光素酶报告基因实验、RNA pull-down实验及Western blot实验验证了该靶向关联。本研究数据显示，miR-204在AML患者血清样本及细胞系中均呈低表达状态。过表达miR-204可抑制AML细胞的增殖、迁移与侵袭，并诱导细胞凋亡。HGF在AML样本及细胞系中呈高表达状态，敲低HGF可抑制AML细胞的恶性表型。此外，HGF可被miR-204直接靶向调控。过表达HGF可逆转miR-204模拟物对AML细胞增殖、凋亡、迁移及侵袭的调控效应。miR-204通过靶向HGF调控c-Met信号通路，进而调节AML细胞中与细胞增殖、凋亡、迁移及侵袭相关的下游蛋白表达水平。综上，miR-204可通过调控HGF/c-Met信号通路参与AML的疾病进展。