MicroRNA-92a-3p-mediated inhibition of BCL11A upregulates γ-globin expression and inhibits oxidative stress and apoptosis in erythroid precursor cells.

ABSTRACT

OBJECTIVE: This study attempted to investigate miR-92a-3p expression in peripheral blood of patients with severe ß-thalassemia, and the effect and action mechanism of miR-92a-3p on γ-globin expression and oxidative stress in erythroid precursor cells. METHODS: CD34+ hematopoietic progenitor cells (HPCs) were isolated from peripheral blood of healthy volunteers and patients with severe ß-thalassemia. The levels of miR-92a-3p, BCL11A, and γ-globin were measured in erythroid precursor cells. High-performance liquid chromatography (HPLC) was used to analyze hemoglobin F (HbF) content. HPCs were induced with erythroid differentiation and erythroid precursor cells were then obtained. The relevance between miR-92a-3p and BCL11A was studied using dual luciferase reporter gene assay, and the correlation between miR-92a-3p and HbF was assayed by Pearson correlation analysis. Reactive oxygen species (ROS), glutathione (GSH), malondialdehyde (MDA), and superoxide dismutase (SOD) in erythroid precursor cells were tested to evaluate oxidative stress. Cell apoptosis was examined by flow cytometry. RESULTS: Remarkably higher expression of miR-92a-3p was observed in erythroid precursor cells. Increased expression of miR-92a-3p resulted in elevated levels of γ-globin, GSH, and SOD, reduced expression of ROS and MDA, and decreased cell apoptosis. BCL11A was identified as a target of miR-92a-3p and to be downregulated by miR-92a-3p. Moreover, BCL11A knockdown alone increased the expression of γ-globin, SOD and GSH, and repressed the levels of ROS and MDA and cell apoptosis, and the following inhibition of miR-92a-3p changed these patterns. CONCLUSIONS: Our data indicated that miR-92a-3p might increase γ-globin level and reduce oxidative stress and apoptosis in erythroid precursor cells by downregulating BCL11A.