ABSTRACT
Background: Several human diseases are associated with aberrant expression of regulators involved in N6-methyladenosine (m6A) RNA modification. However, their role in aortic valve calcification (AVC) is largely unknown. The aim of this study was to determine the general expression pattern and potential function of m6A regulators in AVC by bioinformatics methods. Methods: We obtained AVC datasets from the Gene Expression Omnibus (GEO). The identification of m6A-related differentially expressed genes (DEGs) and the Consensus Clustering method was performed to type AVC individuals based DEGs. Then, we quantified the effect of typing by principal component analysis (PCA). Next, we performed the weighted gene co-expression network analysis (WGCNA) and identified the main modules as well as functional analysis. Additionally, the key genes were screened by protein-protein interaction network (PPIN) analysis and identifying important genes of important modules. We again typed AVC individuals by the same method using key genes. Finally, we evaluated the link between key genes and immune infiltration. Results: We discovered that METTL14, ZC3H13, FTO, FMR1, HNRNPA2B1, HNRNPC, LRPPRC, YTHDC1, YTHDC2, and YTHDF1 expression levels decreased considerably in AVC tissues. Based on 10 genes, we typed 240 AVC samples as clusters A and B. We assessed the immune cell content in 240 samples using Cell-type Identification by Estimating Relative Subsets of RNA Transcripts (CIBERSORT) and found that B cell memory, CD8 T cells, T follicular helper cells, monocytes, M0 macrophages, resting dendritic cells (DCs), and interleukin-10 (IL-10) were concentrated in the cluster A group. Additionally, based on the important WGCNA modules, we identified 7 key genes. Next, 240 samples were retyped based on 7 key genes; we found that T cells CD8, T cells CD4 memory activated, T cells follicular helper, and macrophages M1 were significantly increased in gene cluster-1. Finally, we performed functional enrichment of gene cluster-typed samples, showing potential functional differences between different types. Conclusions: Our study provides a review of the m6A regulators' expression pattern and functional importance in human AVC. The data from this study might serve as a significant resource for future mechanistic and therapeutic investigations into the role of critical m6A regulators in AVC.
ABSTRACT
Objective To investigate the role of Sp1 in the regulation of transcription of vascular endothelial growth factor ( VEGF ) in hypoxia-induced HepG2 cells.Methods Quantitative real-time polymerase chain reaction and immunoblot assay were used to examine the effect of hypoxia on Sp1 protein and VEGF mRNA expression .Mithramycin A, the selective inhibitor of Sp1 and knock-out Sp1 gene with siRNA were used to examine the effect on VEGF mRNA expression induced by hypoxia in HepG2 cells.Results Hypoxia induced Sp1 protein and VEGF mRNA expression in HepG2 cells.Mithramycin A produced a concentration-dependent decrease of hypoxia-induced VEGF mRNA expression . After inhibition of Sp1 RNAi, VEGF mRNA expression was significantly repressed in HepG 2 cells.Conclusion Hypoxia can increase the expression of Sp1 protein and VEGF mRNA in HepG2 cells induced by hypoxia.The transcription of VEGF is regulated by Sp1 in hypoxia-induced HepG2 cells.
ABSTRACT
Objective To investigate the role of Sp1 in the regulation of transcription of vascular endothelial growth factor ( VEGF ) in hypoxia-induced HepG2 cells.Methods Quantitative real-time polymerase chain reaction and immunoblot assay were used to examine the effect of hypoxia on Sp1 protein and VEGF mRNA expression .Mithramycin A, the selective inhibitor of Sp1 and knock-out Sp1 gene with siRNA were used to examine the effect on VEGF mRNA expression induced by hypoxia in HepG2 cells.Results Hypoxia induced Sp1 protein and VEGF mRNA expression in HepG2 cells.Mithramycin A produced a concentration-dependent decrease of hypoxia-induced VEGF mRNA expression . After inhibition of Sp1 RNAi, VEGF mRNA expression was significantly repressed in HepG 2 cells.Conclusion Hypoxia can increase the expression of Sp1 protein and VEGF mRNA in HepG2 cells induced by hypoxia.The transcription of VEGF is regulated by Sp1 in hypoxia-induced HepG2 cells.
