MicroRNA-144 Regulates Cardiomyocyte Proliferation and Apoptosis by Targeting TBX1 through the JAK2/STAT1 Pathway

It is currently believed that the TBX1 gene is one of the core genes of congenital heart disease (CHD). However, there are few studies on the abnormal regulation of TBX1 gene expression. The purpose of this work was to investigate the role of miR-144 and TBX1 in cardiac development by studying the regulatory relationship and mechanism of miR-144 on TBX1/JAK2/STAT1 in cardiomyocytes. Cell proliferation was detected by MTT and clone formation assay and cell cycle and apoptosis by flow cytometry. The levels of miR-144 and TBX1 in H9c2 cells were assessed by qRT-PCR. Dual luciferase reporter assay was used to validate the direct targeting of TBX1 with miR-144. The protein expression levels of TBX1 and its downstream proteins were measured by Western blot analysis. miR-144 inhibited H9c2 cell proliferation by arresting cells in G1 phase. Furthermore, miR-144 induced H9c2 cell apoptosis and activated the JAK2/STAT1 signaling pathway. Bioinformatic predictions and luciferase reporter assay showed that miR-144 directly targets TBX1. Co-overexpression of miR-144 and TBX1 upregulated cell proliferation by accelerating G1 to S phase transition and downregulated cell apoptosis through inhibiting the JAK2/STAT1 signaling pathway. miR-144 acts as a proliferation inhibitor in cardiomyocytes via the TBX1/JAK2/STAT1 axis and is therefore a potential novel therapeutic target for CHD treatment.