WGCNA and LASSO regression-based selection and validation of microRNA biomarkers of β-thalassemia

In patients with severe β-thalassemia, fetal hemoglobin (HbF) upregulation may provide an avenue to better therapeutic outcomes. The mechanisms that regulate the expression of HbF, however, are currently unclear. This study was developed with the goal of exploring biomarkers and molecular mechanisms associated with HbF expression to help inform the development of novel therapeutic strategies.

The GSE93973 dataset from the GEO database was used. These miRNA expression data were subjected to WGCNA, differential expression, and LASSO regression analyses to identify hub miRNAs. The knockdown and overexpression of selected hub miRNAs were performed in K-562 cells to clarify how they affect HbF expression.

In the WGCNA analysis, the module most closely associated with HbF levels was the pink module. Bioinformatics analyses identified miR-19b-3p as the hub miRNA. When miR-19b-3p was overexpressed in K-562 cells, this resulted in HbF upregulation, whereas the opposite was evident when it was knocked down. Dual-luciferase reporter assays confirmed the ability of miR-19b-3p to directly regulate SOX6. SOX6 downregulation was observed when miR-19b-3p was overexpressed, while SOX6 was upregulated following miR-19b-3p knockdown. In rescue experiments, the knockdown of SOX6 was sufficient to partially abrogate the impact of miR-19b-3p knockdown on the expression of HbF.

These results highlight miR-19b-3p as a core miRNA associated with the expression of HbF in β-thalassemia through its ability to regulate SOX6, which allude to a novel mechanism of HbF induction and could provide new targets for increasing HbF in patients with β-thalssemia major.