Targeting the forkhead box protein P1 pathway as a novel therapeutic approach for cardiovascular diseases

LncRNA MIR181A1HG Deficiency Attenuates Vascular Inflammation and Atherosclerosis

BACKGROUND

Endothelial cell (EC) dysfunction and vascular inflammation are critical in the initiation and progression of atherosclerosis. Long noncoding RNAs play a critical role in vascular pathology, but relatively little is known about their involvement in controlling vascular inflammation. MIR181A1HG is a conserved long noncoding RNA located in juxtaposition with miR-181a1 and miR-181b1, both involved in vascular inflammation. The study aims to investigate the role of MIR181A1HG in regulating vascular inflammation.

METHODS

We examined the expression of MIR181A1HG in both human and mouse atherosclerotic lesions. Loss-of-function and gain-of-function studies, and multiple RNA-protein interaction assays were used to investigate the role and molecular mechanisms of MIR181A1HG in vascular inflammation and atherosclerosis. The atherosclerotic phenotypes of MIR181A1HG-/-ApoE-/- mice were analyzed in combination with single-cell RNA sequencing. The transcriptional regulation of MIR181A1HG was verified through luciferase reporter and chromatin immunoprecipitation assays.

RESULTS

MIR181A1HG expression was abundant in ECs and significantly increased in both human and mouse atherosclerotic lesions. MIR181A1HG-/-ApoE-/- mice had reduced NLRP (NLR family pyrin domain containing) 3 inflammasome signaling, EC activation, monocyte infiltration, and atherosclerotic lesion formation. Genetic deletion of MIR181A1HG in myeloid sells did not alter the progression of atherosclerosis. Single-cell RNA sequencing analysis revealed that MIR181A1HG deficiency reduced the proportion of immune cells and enriched anti-inflammation pathways in EC clusters in atherosclerotic lesions. In contrast, EC-specific MIR181A1HG overexpression promoted NLRP3 inflammasome signaling, EC activation, and atherosclerotic lesion formation, effects that were reversed by pharmacological inhibition of NLRP3 (MCC950). MIR181A1HG was transcriptionally activated via an NF-κB (nuclear factor kappa B)/p65-dependent pathway. Mechanistically, MIR181A1HG mediated these effects on regulating NLRP3 inflammasome and EC activation in part through decoying Foxp1 (forkhead box transcription factor 1) away from the promoters of target genes, which was independent of the miR-181a1/b1 cluster. Finally, EC-specific Foxp1 silencing reversed the antiatherosclerotic effect mediated by MIR181A1HG-deletion in vivo.

CONCLUSIONS

These findings identify MIR181A1HG as a central driver of vascular inflammation in atherosclerosis by its ability to decoy Foxp1 away from target gene promoters and activate NLRP3 inflammasome in the vascular endothelium. Our study suggests MIR181A1HG as a future therapeutic target for vascular inflammatory disease states.

SRSF4-Associated ca-circFOXP1 Regulates Hypoxia-Induced PASMC Proliferation by the Formation of R Loop With Host Gene

BACKGROUND

Pulmonary hypertension (PH) is a rare and fatal disease, the pathological changes of which include pulmonary arterial smooth muscle cell (PASMC) proliferation, which is the pathological basis of pulmonary vascular remodeling. Studies have demonstrated that chromatin-associated circRNA can regulate a variety of biological processes. However, the role of chromatin-associated circRNA in the proliferation of PH remains largely unexplored. In this study, we aimed to identify the function and mechanism of chromatin-associated circRNA in PASMC proliferation in PH.

METHODS

The role of chromatin-associated circFOXP1 (ca-circFOXP1) was investigated in hypoxic mouse PASMCs and SuHX (Sugen5416+hypoxia) model mice through the use of antisense oligonucleotide knockdown and adeno-associated virus-mediated knockdown. Through bioinformatic sequence alignment, chromatin isolation by RNA purification, Cell Counting Kit 8, 5-ethynyl-2-deoxyuridine, Western blot, and other experiments, the function and mechanism of ca-circFOXP1 were verified.

RESULTS

The expression of ca-circFOXP1 was found to be significantly increased in SuHX model mice and hypoxic mouse PASMCs. Moreover, ca-circFOXP1 was found to regulate the level of the host protein FOXP1 (forkhead box protein 1) through the R loop, thereby influencing the phosphorylation activity of SMAD2 (SMAD family member 2) and, consequently, the proliferation of mouse PASMCs. It is noteworthy that the m6A modification was found to promote the formation of the R loop between ca-circFOXP1 and the host gene FOXP1, thereby regulating the expression of the host protein. Furthermore, we have identified that the splicing factor SRSF4 (serine/arginine rich splicing factor 4) can upregulate the expression of ca-circFOXP1 by splicing exons 6 and 9 of FOXP1 pre-mRNA.

CONCLUSIONS

The results demonstrated that the splicing factor SRSF4 upregulated the expression of ca-circFOXP1, and m6A methylation promoted R-loop formation between ca-circFOXP1 and host genes, regulated the level of host protein FOXP1, and then affected the phosphorylation activity of SMAD2, mediating PASMC proliferation, leading to pulmonary vascular remodeling. These results provide a theoretical basis for further study of the pathological mechanisms of hypoxic PH and may provide certain insights.

Bioinformatics analysis of the expression of potential common genes and immune-related genes between atrial fibrillation and chronic kidney disease

Research objective

This study is based on bioinformatics analysis to explore the co-expressed differentially expressed genes (DEGs) between atrial fibrillation (AF) and chronic kidney disease (CKD), identify the biomarkers for the occurrence and development of the two diseases, investigate the potential connections between AF and CKD, and explore the associations with immune cells.

Methods

We downloaded Two AF gene chip datasets (GSE79768, GSE14975) and two CKD gene chip datasets (GSE37171, GSE120683) from the GEO database. After pre-processing and standardizing the datasets, two DEGs datasets were obtained. The DEGs were screened using R language, and the intersection was taken through Venn diagrams to obtain the co-expressed DEGs of AF and CKD. To obtain the signal pathways where the co-expressed DEGs were significantly enriched, GO/KEGG enrichment analyses were used to analysis the co-expressed DEGs. The Cytoscape software was used to further construct a PPI network and screen key characteristic genes, and the top 15 co-expressed DEGs were screened through the topological algorithm MCC. To further screen key characteristic genes, two machine-learning algorithms, LASSO regression and RF algorithm, were performed to screen key characteristic genes for the two disease datasets respectively to determine the diagnostic values of the characteristic genes in the two diseases. The GeneMANIA online database and Networkanalyst platform were used to construct gene-gene and TFs-gene interaction network diagrams respectively to predict gene functions and find key transcription factors. Finally, the correlation between key genes and immune cell subtypes was performed by Spearman analysis.

Research results

A total of 425 DEGs were screened out from the AF dataset, and 4,128 DEGs were screened out from the CKD dataset. After taking the intersection of the two, 82 co-expressed DEGs were obtained. The results of GO enrichment analysis of DEGs showed that the genes were mainly enriched in biological processes such as secretory granule lumen, blood microparticles, complement binding, and antigen binding. KEGG functional enrichment analysis indicated that the genes were mainly enriched in pathways such as the complement coagulation cascade, systemic lupus erythematosus, and Staphylococcus aureus infection. The top 15 DEGs were obtained through the MCC topological algorithm of Cytoscape software. Subsequently, based on LASSO regression and RF algorithm, the key characteristic genes of the 15 co-expressed DEGs of AF and CKD were further screened, and by taking the intersection through Venn diagrams, five key characteristic genes were finally obtained: PPBP, CXCL1, LRRK2, RGS18, RSAD2. ROC curves were constructed to calculate the area under the curve to verify the diagnostic efficacy of the key characteristic genes for diseases. The results showed that RSAD2 had the highest diagnostic value for AF, and the diagnostic values of PPBP, CXCL1, and RSAD2 for CKD were all at a relatively strong verification level. Based on AUC >0.7, co-expressed key genes with strong diagnostic efficacy were obtained: PPBP, CXCL1, RSAD2. The results of the GeneMANIA online database showed that the two biomarkers, BBPB and CXCL1, mainly had functional interactions with cytokine activity, chemokine receptor activity, cell response to chemokines, neutrophil migration, response to chemokines, granulocyte chemotaxis, and granulocyte migration. The TFs-gene regulatory network identified FOXC1, FOXL1, and GATA2 as the main transcription factors of the key characteristic genes. Finally, through immune infiltration analysis, the results indicated that there were various immune cell infiltrations in the development processes of AF and CKD.

Research conclusion

PPBP, CXCL1, and RSAD2 are key genes closely related to the occurrence and development processes between AF and CKD. Among them, the CXCLs/CXCR signaling pathway play a crucial role in the development processes of the two diseases likely. In addition, FOXC1, FOXL1, and GATA2 may be potential therapeutic targets for AF combined with CKD, and the development of the diseases is closely related to immune cell infiltration.

The Reparative Effect of FOXM1 in Pulmonary Disease

FOXM1, a key member of the FOX transcription factor family, maintains cell homeostasis by accurately controlling diverse biological processes, such as proliferation, cell cycle progression, differentiation, DNA damage repair, tissue homeostasis, angiogenesis, apoptosis, redox signaling, and drug resistance. In recent years, an increasing number of studies have focused on the role of FOXM1 in the occurrence of multiple diseases and various pathophysiological processes. In the field of pulmonary diseases, FOXM1 has a certain reparative effect by promoting cell proliferation, regulating cell cycle, antifibrosis, participating in inflammation regulation, and synergizing with other signaling pathways. On the basis of the repair properties of FOXM1, this review explores its therapeutic potential in acute lung injury/acute respiratory distress syndrome, asthma, chronic obstructive pulmonary disease, idiopathic pulmonary fibrosis, pulmonary arterial hypertension, lung cancer, and other lung diseases, with the goal of providing a new perspective for the analysis of FOXM1-related mechanism of action and the expansion of clinical treatment strategies.

Identification of FOXP1 as a favorable prognostic biomarker and tumor suppressor in intrahepatic cholangiocarcinoma

BACKGROUND

Forkhead-box protein P1 (FOXP1) has been proposed to have both oncogenic and tumor-suppressive properties, depending on tumor heterogeneity. However, the role of FOXP1 in intrahepatic cholangiocarcinoma (ICC) has not been previously reported.

METHODS

Immunohistochemistry was performed to detect FOXP1 expression in ICC and normal liver tissues. The relationship between FOXP1 levels and the clinicopathological characteristics of patients with ICC was evaluated. Finally, in vitro and in vivo experiments were conducted to examine the regulatory role of FOXP1 in ICC cells.

RESULTS

FOXP1 was significantly downregulated in the ICC compared to their peritumoral tissues (p < 0.01). The positive rates of FOXP1 were significantly lower in patients with poor differentiation, lymph node metastasis, invasion into surrounding organs, and advanced stages (p < 0.05). Notably, patients with FOXP1 positivity had better outcomes (overall survival) than those with FOXP1 negativity (p < 0.05), as revealed by Kaplan-Meier survival analysis. Moreover, Cox multivariate analysis showed that negative FOXP1 expression, advanced TNM stages, invasion, and lymph node metastasis were independent prognostic risk factors in patients with ICC. Lastly, overexpression of FOXP1 inhibited the proliferation, migration, and invasion of ICC cells and promoted apoptosis, whereas knockdown of FOXP1 had the opposite role.

CONCLUSION

Our findings suggest that FOXP1 may serve as a novel outcome predictor for ICC as well as a tumor suppressor that may contribute to cancer treatment.

MiR-522-3p Attenuates Cardiac Recovery by Targeting FOXP1 to Suppress Angiogenesis

Angiogenesis is crucial for blood supply reconstitution after myocardial infarction in patients with acute coronary syndrome (ACS). MicroRNAs are recognized as important epigenetic regulators of endothelial angiogenesis. The purpose of this study is to determine the roles of miR-522-3p in angiogenesis after myocardial infarction. The expression levels of miR-522-3p in rats' plasma and in the upper part of the ligation of the heart tissues at 28 days after myocardial infarction were significantly higher than those of the sham group. miR-522-3p mimics inhibited cell proliferations, migrations, and tube formations under hypoxic conditions in HUVECs (human umbilical vein endothelial cells), whereas miR-522-3p inhibitors did the opposite. Furthermore, studies have indicated that the inhibition of miR-522-3p by antagomir infusion promoted angiogenesis and accelerated the recovery of cardiac functions in rats with myocardial infarction.Data analysis and experimental results revealed that FOXP1 (Forkhead-box protein P1) was the target gene of miR-522-3p. Our study explored the mechanism of cardiac angiogenesis after myocardial infarction and provided a potential therapeutic approach for the treatment of ischemic heart disease in the future.

FOXP1‑induced DUSP12 alleviates vascular endothelial cell inflammation and oxidative stress injury induced by ox‑LDL via MAP3K5 signaling pathway

Atherosclerosis (AS) is a type of chronic inflammatory disease and the main pathological basis of cardiovascular and cerebrovascular diseases, which seriously threaten the health of patients. The dual specificity phosphatase 12 (DUSP12) protein is known as regulator of inflammatory diseases. Nonetheless, at present, there are only a few reports on the regulatory role of DUSP12 in AS. Human umbilical vein endothelial cells (HUVECs) were induced using oxidized low-density lipoprotein (ox-LDL). Subsequently, cell transfection experiments were performed to overexpress DUSP12 in ox-LDL-induced HUVECs. Cell Counting Kit-8, TUNEL western blotting, 2',7'-dichlorofluorescein diacetate assays, ELISA and other techniques were used to measure cell viability, apoptosis, inflammation, oxidative stress and endothelial function-related indicators. Subsequently, the relationship between DUSP12 and Forkhead box P1 (FOXP1) was predicted using the JASPAR database and verified using luciferase reporter and chromatin immunoprecipitation assays. Finally, the regulatory mechanism was investigated by simultaneously overexpressing DUSP12 and knocking down FOXP1 in ox-LDL-induced HUVECs and MAP3K5-related proteins of the DUSP12 downstream pathway were measured by western blotting. The expression of DUSP12 in ox-LDL-induced HUVECs was significantly decreased. Overexpression of DUSP12 inhibited apoptosis, inflammation and oxidative stress damage and alleviated endothelial dysfunction in ox-LDL-induced HUVECs. FOXP1 promoted the transcription of DUSP12. Moreover, FOXP1 alleviated ox-LDL-induced apoptosis, inflammation and oxidative stress damage in HUVECs by regulating the expression of DUSP12, probably acting through the MAP3K5 pathway. Collectively, the present study revealed that FOXP1-induced DUSP12 alleviated vascular endothelial cell inflammation and oxidative stress injury in ox-LDL-induced HUVECs via the MAP3K5 signaling pathway, which might shed novel insights into the targeted treatment for AS in the clinic.

FOXM1: A small fox that makes more tracks for cancer progression and metastasis

Transcription factors (TFs) are indispensable for the modulation of various signaling pathways associated with normal cell homeostasis and disease conditions. Among cancer-related TFs, FOXM1 is a critical molecule that regulates multiple aspects of cancer cells, including growth, metastasis, recurrence, and stem cell features. FOXM1 also impact the outcomes of targeted therapies, chemotherapies, and immune checkpoint inhibitors (ICIs) in various cancer types. Recent advances in cancer research strengthen the cancer-specific role of FOXM1, providing a rationale to target FOXM1 for developing targeted therapies. This review compiles the recent studies describing the pivotal role of FOXM1 in promoting metastasis of various cancer types. It also implicates the contribution of FOXM1 in the modulation of chemotherapeutic resistance, antitumor immune response/immunotherapies, and the potential of small molecule inhibitors of FOXM1.

BRD9-mediated chromatin remodeling suppresses osteoclastogenesis through negative feedback mechanism

Bromodomain-containing protein 9 (BRD9), a component of non-canonical BAF chromatin remodeling complex, has been identified as a critical therapeutic target in hematological diseases. Despite the hematopoietic origin of osteoclasts, the role of BRD9 in osteoclastogenesis and bone diseases remains unresolved. Here, we show Brd9 deficiency in myeloid lineage enhances osteoclast lineage commitment and bone resorption through downregulating interferon-beta (IFN-β) signaling with released constraint on osteoclastogenesis. Notably, we show that BRD9 interacts with transcription factor FOXP1 activating Stat1 transcription and IFN-β signaling thereafter. Besides, function specificity of BRD9 distinguished from BRD4 during osteoclastogenesis has been evaluated. Leveraging advantages of pharmacological modulation of BRD9 and flexible injectable silk fibroin hydrogel, we design a local deliver system for effectively mitigating zoledronate related osteonecrosis of the jaw and alleviating acute bone loss in lipopolysaccharide-induced localized aggressive periodontitis. Overall, these results demonstrate the function of BRD9 in osteoclastogenesis and its therapeutic potential for bone diseases.

FOXP1 inhibits pancreatic cancer growth by transcriptionally regulating IRF1 expression

FOXP1, known as a Forkhead-box (FOX) family protein, plays an important role in human tumorigenesis. However, the function and molecular mechanism of FOXP1 in pancreatic cancer (PC) remain unclear. Here, we report that PC patients with FOXP1 overexpression had a higher survival rate compared to patients with low- FOXP1 expression. Additionally, high expression of FOXP1 can markedly inhibit the growth of pancreatic cancer in vivo and in vitro, whereas low expression of FOXP1 effectively promoted the tumorigenesis. Mechanistically, FOXP1 could directly bind the IRF1 promoter, which triggered the transcriptional activity of IRF1. Taken together, FOXP1 suppressed PC growth via IRF1-dependent manner, serving as a potential prognostic biomarker for patients with PC.