[Effect of Negative Regulation of LncRNA XIST to MiR-196b on the Biological Behavior of Acute Myeloid Leukemia Cells KG1a].

Abstract

Objective: To investigate the effect and molecular mechanism of lncRNA X-inactive specific transcript (XIST) on the proliferation and apoptosis of acute myeloid leukemia cells KG1a.

Methods: Forty-one patients with acute myeloid leukemia from January 2017 to May 2019 treated in Beijing Aerospace Center Hospital were collected, as well as 20 patients who conformed to the international standard of iron deficiency anemia as control group. KG1a cells were divided into pcDNA group, pcDNA-XIST group, pcDNA-XIST+miR-NC group, and pcDNA-XIST+miR-196b group. Real-time fluorescence quantitative PCR was used to detect the expressions of XIST and miR-196b, CCK-8 was used to detect cell activity, flow cytometry was used to detect cell cycle and apoptosis, Western blot method was used to detect the protein expressions of cleaved-caspase3, pro-caspase3, Bax, and Bcl-2, and dual luciferase report experiment was used to detect the targeting relationship between XIST and miR-196b.

Results: The expression level of lncRNA XIST in bone marrow cells in the AML group was significantly lower than that in the iron deficiency anemia group (P<0.001). Compared with pcDNA group, the expression level of lncRNA XIST, proportion of cells in G₀/G₁ phase, apoptosis rate, and the expression levels of cleaved-caspase3 and Bax in the pcDNA-XIST group of KG1a cells were significantly increased (all P<0.001), while the expression level of miR-196b, cell viability, the proportion of S-phase cells, and the expression levels of pro-caspase3 and Bcl-2 were significantly decreased (all P<0.001). Compared with pcDNA-XIST group, the cell activity, proportion of S-phase cells, and the expression levels of pro-caspase3 and Bcl-2 in the pcDNA-XIST+miR-196b group were significantly increased (all P<0.001), while the proportion of cells in the G₀/G₁ phase, apoptosis rate, and the expression levels of cleaved-caspase3 and Bax decreased (all P<0.001).

Conclusion: Overexpression of lncRNA XIST can inhibit the proliferation of acute myeloid leukemia cells KG1a and promote apoptosis by down-regulating the expression of miR-196b.