Nuclear receptor subfamily 4 group A member 1 (NR4A1) acts as a myogenic factor in muscle development and regeneration; however, it remains unclear how Nr4a1 regulates myoblast physiology. In this study, report a role for Nr4a1-mediated regulation of cell adhesion in myoblast and muscle tissue. Nr4a1-overexpression myoblast, Nr4a1-konckdown myoblast and mice gastrocnemius muscle following an injection with an adenovirus vector expression Nr4a1 (Nr4a1-AAV) were used to observe the changes in cell adhesion. Nr4a1 was found to enhance cell-cell contact and adhesion molecule expression in myoblasts. In contrast, the deletion of Nr4a1 expression inhibited junction and adhesion between myoblasts. Moreover, Nr4a1 increased myoblast adhesion via directly binding to an upstream site of zinc finger E-box binding homeobox 1 (Zeb1), which is required for myogenesis in myoblasts. In mice, Zeb1 induced increased cadherin and integrin expression in the gastrocnemius muscle following an injection with an adenovirus vector expressing Nr4a1(Nr4a1-AAV). These data indicate that Nr4a1 regulates myoblast adhesion via Zeb1 expression.

The nuclear receptor subfamily 2 group F member 2 (NR2F2) gene encodes a ligand-inducible transcription factor involved in angiogenesis and heart development. This study aimed to elucidate the molecular mechanism of epigenetic regulation of NR2F2 in tetralogy of Fallot (TOF) development. In the present study, immunohistochemical staining showed that NR2F2 protein expression was significantly higher in the right ventricular outflow tract (RVOT) tissues of TOF cases compared with controls. The methylation status of the CpG island shore (CGIS) of the NR2F2 gene was decreased in TOF cases, and the CpG site 3 in the CGIS region of NR2F2 promoter was a differential methylation site. Furthermore, the methylation level of the CpG site 3 and the NR2F2 protein expression were significantly negatively correlated in TOF patients. In vitro functional analysis revealed that RXRα could upregulate the NR2F2 gene by directly binding to the CGIS in the NR2F2 promoter, while hypomethylation of the NR2F2 promoter via treatment with 5-azacytidine influenced the affinity of RXRα to its binding sites, as shown by ChIP-qPCR. These findings suggest that promoter hypomethylation activates NR2F2 by enhancing RXRα binding to NR2F2 CGIS in the development of TOF.

Lung cancer is the leading cause of cancer-mediated death. Although various therapeutic approaches are used for lung cancer treatment, these mainly target the tumor suppressor p53 transcription factor, which is involved in apoptosis and cell cycle arrest. However, p53-targeted therapies have limited application in lung cancer, since p53 is found to be mutated in more than half of lung cancers. In this study, we propose tumor suppressor FOXA2 as an alternative target protein for therapies against lung cancer and reveal a possible FOXA2-centered transcriptional regulation network by identifying new target genes and binding partners of FOXA2 by using various screening techniques. The genes encoding Glu/Asp-rich carboxy-terminal domain 2 (CITED2), nuclear receptor subfamily 0, group B, member 2 (NR0B2), cell adhesion molecule 1 (CADM1) and BCL2-associated X protein (BAX) were identified as putative target genes of FOXA2. Additionally, the proteins including highly similar to heat shock protein HSP 90-beta (HSP90A), heat shock 70 kDa protein 1A variant (HSPA1A), histone deacetylase 1 (HDAC1) and HDAC3 were identified as novel interacting partners of FOXA2. Moreover, we showed that FOXA2-dependent promoter activation of BAX and p21 genes is significantly reduced via physical interactions between the identified binding partners and FOXA2. These results provide opportunities to understand the FOXA2-centered transcriptional regulation network and novel therapeutic targets to modulate this network in p53-deficient lung cancer.