MAGP1, the extracellular matrix, and metabolism

MFAP2 promotes HSCs activation through FBN1/TGF-β/Smad3 pathway

Liver fibrosis is a chronic inflammatory process characterized by the accumulation of extracellular matrix (ECM), which contributes to cirrhosis and hepatocellular carcinoma. Increasing evidence suggests that the activation of hepatic stellate cells (HSCs) under an inflammatory state leads to the secretion of collagens, which can cause cirrhosis. In this study, we analysed data from the Gene Expression Omnibus (GEO) databases to identify differentially expressed genes (DEGs) between quiescent and fibrotic HSCs. We found that Microfibril Associated Protein 2 (MFAP2) was elevated in carbon tetrachloride (CCl4)-induced liver fibrosis and Transforming Growth Factor-Beta 1 (TGF-β1)-activated HSCs. Knockdown of MFAP2 inhibited HSC proliferation and partially attenuated TGF-β-stimulated fibrogenesis markers. Bioinformatics analysis revealed that Fibrillin-1 (FBN1) was correlated with MFAP2, and the expression of FBN1 was significantly upregulated after MFAP2 overexpression. Silencing MFAP2 partially attenuated the activation of HSCs by inhibiting HSC proliferation and decreasing collagen deposits. In vitro results showed that the inhibition of MFAP2 alleviated hepatic fibrosis by inhibiting the activation and inducing the apoptosis of active HSCs in a CCl4-induced mouse model. In conclusion, our results suggest that MFAP2 is a potential target for the clinical treatment of liver fibrosis.

The role of microfibrillar‐associated protein 2 in cancer

Microfibrillar-associated protein 2 (MFAP2), a component of the extracellular matrix, is important in controlling growth factor signal transduction. Recent studies have shown that MFAP2, an effective prognostic molecule for various tumors, is associated with tumor occurrence and development and may be involved in remodeling the extracellular matrix and regulating proliferation, apoptosis, invasion, tumor cell metastasis, and tumor angiogenesis. However, MFAP2’s specific mechanism in these tumor processes remains unclear. This article reviewed the possible mechanism of MFAP2 in tumorigenesis and progression and provided a reference for the clinical prognosis of patients with cancer and new therapeutic target discovery.

MFAP2 aggravates tumor progression through activating FOXM1/β-catenin-mediated glycolysis in ovarian cancer

Ovarian cancer is one of the most common gynecological tumors that seriously endanger the health and quality of life of women. Microfibril-associated protein 2 (MFAP2) has been demonstrated to play crucial roles in the development of multiple tumors. However, the function of MFAP2 in ovarian cancer remains unclear. In this study, we found that MFAP2 was upregulated in ovarian cancer and cells and was positively correlated with FOXM1 and glycolysis-related genes. The results of Cell Count Kit-8, colony formation, and flow cytometry assays indicated that MFAP2 promoted cell proliferation. In addition, MFAP2 promotes cell proliferation, glucose uptake, lactate production; increases ATP levels, extracellular acidification ratio, and oxygen consumption ratio in ovarian cancer cells and increases the expression of glycolytic proteins. Further mechanistic analysis suggests that MFAP2 promotes FOXM1/β-catenin-mediated glycolysis signaling in ovarian cancer cells. Knockdown of MFAP2 inhibits ovarian cancer xenograft tumor growth and expression of Ki-67, MFAP2, FOXM1, GLUT1, HK2, and β-catenin in mice. In conclusion, MFAP2 promotes cell proliferation and glycolysis by modulating the FOXM1/β-catenin signaling pathway in ovarian cancer, which may offer a fresh insight into the treatment of ovarian cancer in the glycolysis pathway.

Integrative bioinformatics analysis of potential therapeutic targets and immune infiltration characteristics in dilated cardiomyopathy

Background

Dilated cardiomyopathy (DCM) is currently the major cause of systolic heart failure. This study explored potential therapeutic targets and investigated the role of immune cell infiltration in DCM.

Methods

Three DCM datasets (GSE3585, GSE9800, and GSE84796) from the Gene Expression Omnibus (GEO) database were merged into an integrated dataset, and batch effects were removed. Differentially expressed genes (DEGs) were screened and the associations between gene co-expression modules and clinical traits were assessed by weighted gene co-expression network analysis (WGCNA) in R software. Any DEGs from the integrated dataset overlapped with the significant module genes were defined as common genes (CGs). Enrichment analysis of the CGs was performed. The protein-protein interaction (PPI) network of the CGs was visualized and the hub gene was identified by using Cytoscape 3.8.2 software. The miRNA-transcription factor-mRNA (miRNA-TF-mRNA) network was constructed using Cytoscape to unveil the regulatory relationships in DCM. Finally, the CIBERSORT method (https://cibersort.stanford.edu/) was used to investigate immune cell infiltration in DCM.

Results

A total of 53 DEGs were identified, and 5 gene co-expression modules were detected by WGCNA of the DCM and control group samples of cardiac tissue. Genes such as FRZB, ASPN, and PHLDA1 were significantly upregulated, whereas IDH2 and ENDOG were significantly downregulated. Functional enrichment analysis showed that CGs were mainly enriched in the extracellular matrix (ECM) signaling pathway. ASPN was the hub gene in the PPI network. The miRNA-TF-mRNA network revealed that FRZB and ASPN were targeted by paired related homeobox 2 (Prrx2). We also found that miR-129-5p could regulate ASPN, PHLDA1, and IDH2 simultaneously. The immune infiltration analysis revealed higher levels of M1 macrophages in DCM samples than in the control samples.

Conclusions

In conclusion, we speculate that miR-129-5p might target ASPN in regulating DCM via the ECM signaling pathway. Macrophage infiltration may be involved in ECM remodeling and eventually lead to DCM.

Zebrafish as a Model to Study Vascular Elastic Fibers and Associated Pathologies

Many extensible tissues such as skin, lungs, and blood vessels require elasticity to function properly. The recoil of elastic energy stored during a stretching phase is provided by elastic fibers, which are mostly composed of elastin and fibrillin-rich microfibrils. In arteries, the lack of elastic fibers leads to a weakening of the vessel wall with an increased risk to develop cardiovascular defects such as stenosis, aneurysms, and dissections. The development of new therapeutic molecules involves preliminary tests in animal models that recapitulate the disease and whose response to drugs should be as close as possible to that of humans. Due to its superior in vivo imaging possibilities and the broad tool kit for forward and reverse genetics, the zebrafish has become an important model organism to study human pathologies. Moreover, it is particularly adapted to large scale studies, making it an attractive model in particular for the first steps of investigations. In this review, we discuss the relevance of the zebrafish model for the study of elastic fiber-related vascular pathologies. We evidence zebrafish as a compelling alternative to conventional mouse models.

Upregulation of microfibrillar-associated protein 2 is closely associated with tumor angiogenesis and poor prognosis in hepatocellular carcinoma

Abnormal expression of microfibrillar-associated protein 2 (MFAP2), a key regulator of cellular differentiation, affects the occurrence and progression of tumors. However, the underlying role of MAFP2 in hepatocellular carcinoma (HCC) remains unclear. In the present study, patterns of MFAP2 expression in HCC were analyzed using sequencing data from The Cancer Genome Atlas database. Expression profiles of MFAP2, as well as those of epithelial-mesenchymal transition (EMT)-related proteins, were compared between HCC pathological sections and fresh tissues. Thereafter, associations between patterns of MFAP2 expression and the clinicopathological characteristics of patients, and identified risk factors associated with disease-free survival (DFS) and overall survival (OS), were determined. The functions of MFAP2 in the EMT-induced proliferation and migration of MHCC97H cells were investigated using in vitro experiments, and the effects of MFAP2 on vascular endothelial growth factor A (VEGFA)-induced tumor angiogenesis were also investigated. Upregulation of MFAP2 expression was observed in HCC, and was often accompanied by the abnormal expression of EMT-related marker proteins. In addition, analysis of clinical data from 94 patients with tumor tissues revealed a significant positive correlation between MFAP2 expression and low DFS and low OS following surgery. Through in vitro experimentation, silencing MFAP2 expression was shown inhibit EMT, which thereby inhibited cellular proliferation and migration. Moreover, downregulation of MFAP2 inhibited tumor angiogenesis via the inhibition of VEGFA. Taken together, these findings indicate that MFAP2 has the potential to predict the prognosis of patients with HCC. MFAP2 also induces tumor cell proliferation and migration through EMT, and promotes tumor blood vessel formation through VEGFA, suggesting that MFAP2 may be a potential therapeutic target for HCC.

Decreased Levels of Microfibril-Associated Glycoprotein (MAGP)-1 in Patients with Colon Cancer and Obesity Are Associated with Changes in Extracellular Matrix Remodelling

OBJECTIVE

The protein microfibril-associated glycoprotein (MAGP)-1 constitutes a crucial extracellular matrix protein. We aimed to determine its impact on visceral adipose tissue (VAT) remodelling during obesity-associated colon cancer (CC).

METHODS

Samples obtained from 79 subjects (29 normoponderal (NP) (17 with CC) and 50 patients with obesity (OB) (19 with CC)) were used in the study. Circulating concentrations of MAGP-1 and its gene expression levels (MFAP2) in VAT were analysed. The impact of inflammation-related factors and adipocyte-conditioned media (ACM) on MFAP2 mRNA levels in colon adenocarcinoma HT-29 cells were further analysed. The effects of MAGP-1 in the expression of genes involved in the extracellular matrix (ECM) remodelling and tumorigenesis in HT-29 cells was also explored.

RESULTS

Obesity (p < 0.01) and CC (p < 0.001) significantly decreased MFAP2 gene expression levels in VAT whereas an opposite trend in TGFB1 mRNA levels was observed. Increased mRNA levels of MFAP2 after the stimulation of HT-29 cells with lipopolysaccharide (LPS) (p < 0.01) and interleukin (IL)-4 (p < 0.01) together with a downregulation (p < 0.05) after hypoxia mimicked by CoCl₂ treatment was observed. MAGP-1 treatment significantly enhanced the mRNA levels of the ECM-remodelling genes collagen type 6 α3 chain (COL6A3) (p < 0.05), decorin (DCN) (p < 0.01), osteopontin (SPP1) (p < 0.05) and TGFB1 (p < 0.05). Furthermore, MAGP-1 significantly reduced (p < 0.05) the gene expression levels of prostaglandin-endoperoxide synthase 2 (COX2/PTGS2), a key gene controlling cell proliferation, growth and adhesion in CC. Interestingly, a significant decrease (p < 0.01) in the mRNA levels of MFAP2 in HT-29 cells preincubated with ACM from volunteers with obesity compared with control media was observed. Conclusion: The decreased levels of MAGP-1 in patients with obesity and CC together with its capacity to modulate key genes involved in ECM remodelling and tumorigenesis suggest MAGP-1 as a link between AT excess and obesity-associated CC development.

Microfibril-Associated Protein 2 (MFAP2) Potentiates Invasion and Migration of Melanoma by EMT and Wnt/β-Catenin Pathway

Background

Growing evidence indicates an association between microfibril-associated protein 2 (MFAP2) and a number of physiological and pathological mechanisms. The potential role of MFAP2 in cancer requires further elucidation. The present study investigated the biological behavior of MFAP2 in melanoma patients.

Material/Methods

MFAP2 inhibition was established in the B16 melanoma cell line through the use of RNA interference and was assessed by quantitative real-time PCR (qRT-PCR) and Western blot analysis. Wound-healing analysis, transwell assay, and in vivo imaging were performed to investigate the roles of MFAP2 reducing cell mobility, migration, and invasion abilities in vitro and in vivo.

Results

We found substantially higher MFAP2 expression in B16 melanoma cells. The knockdown of MFAP2 inhibited B16 melanoma cells migration and invasion. Western blot analysis was used to assess changes in biomarkers of EMT, indicating the function of MFAP2 in EMT. We found that downregulation of MFAP2 altered the expression of Wnt/β-catenin-linked protein.

Conclusions

Our results suggest that MFAP2 has potential as a molecular target to treat melanoma and suppress metastasis of melanoma cells.

The cartilage matrisome in adolescent idiopathic scoliosis

The human spinal column is a dynamic, segmented, bony, and cartilaginous structure that protects the neurologic system and simultaneously provides balance and flexibility. Children with developmental disorders that affect the patterning or shape of the spine can be at risk of neurologic and other physiologic dysfunctions. The most common developmental disorder of the spine is scoliosis, a lateral deformity in the shape of the spinal column. Scoliosis may be part of the clinical spectrum that is observed in many developmental disorders, but typically presents as an isolated symptom in otherwise healthy adolescent children. Adolescent idiopathic scoliosis (AIS) has defied understanding in part due to its genetic complexity. Breakthroughs have come from recent genome-wide association studies (GWAS) and next generation sequencing (NGS) of human AIS cohorts, as well as investigations of animal models. These studies have identified genetic associations with determinants of cartilage biogenesis and development of the intervertebral disc (IVD). Current evidence suggests that a fraction of AIS cases may arise from variation in factors involved in the structural integrity and homeostasis of the cartilaginous extracellular matrix (ECM). Here, we review the development of the spine and spinal cartilages, the composition of the cartilage ECM, the so-called "matrisome" and its functions, and the players involved in the genetic architecture of AIS. We also propose a molecular model by which the cartilage matrisome of the IVD contributes to AIS susceptibility.

MFAP2 is overexpressed in gastric cancer and promotes motility via the MFAP2/integrin α5β1/FAK/ERK pathway

Gastric cancer (GC) is one of the most common malignancies and its prognosis is extremely poor. This study identifies a novel oncogene, microfibrillar-associated protein 2 (MFAP2) in GC. With integrative reanalysis of transcriptomic data, we found MFAP2 as a GC prognosis-related gene. And the aberrant expression of MFAP2 was explored in GC samples. Subsequent experiments indicated that silencing and exogenous MFAP2 could affect motility of cancer cells. The inhibition of silencing MFAP2 could be rescued by another FAK activator, fibronectin. This process is probably through affecting the activation of focal adhesion process via modulating ITGB1 and ITGA5. MFAP2 regulated integrin expression through ERK1/2 activation. Silencing MFAP2 by shRNA inhibited tumorigenicity and metastasis in nude mice. We also revealed that MFAP2 is a novel target of microRNA-29, and miR-29/MFAP2/integrin α5β1/FAK/ERK1/2 could be an important oncogenic pathway in GC progression. In conclusion, our data identified MFAP2 as a novel oncogene in GC and revealed that miR-29/MFAP2/integrin α5β1/FAK/ERK1/2 could be an important oncogenic pathway in GC progression.

Microfibril-associated glycoproteins MAGP-1 and MAGP-2 in disease

Microfibril-associated glycoproteins 1 and 2 (MAGP-1, MAGP-2) are protein components of extracellular matrix microfibrils. These proteins interact with fibrillin, the core component of microfibrils, and impart unique biological properties that influence microfibril function in vertebrates. MAGPs bind active forms of TGFβ and BMPs and are capable of modulating Notch signaling. Mutations in MAGP-1 or MAGP-2 have been linked to thoracic aneurysms and metabolic disease in humans. MAGP-2 has also been shown to be an important biomarker in several human cancers. Mice lacking MAGP-1 or MAGP-2 have defects in multiple organ systems, which reflects the widespread distribution of microfibrils in vertebrate tissues. This review summarizes our current understanding of the function of the MAGPs and their relationship to human disease.

The microfibril-associated glycoproteins (MAGPs) and the microfibrillar niche

The microfibril-associated glycoproteins MAGP-1 and MAGP-2 are extracellular matrix proteins that interact with fibrillin to influence microfibril function. The two proteins are related through a 60 amino acid matrix-binding domain but their sequences differ outside of this region. A distinguishing feature of both proteins is their ability to interact with TGFβ family growth factors, Notch and Notch ligands, and multiple elastic fiber proteins. MAGP-2 can also interact with αvβ3 integrins via a RGD sequence that is not found in MAGP-1. Morpholino knockdown of MAGP-1 expression in zebrafish resulted in abnormal vessel wall architecture and altered vascular network formation. In the mouse, MAGP-1 deficiency had little effect on elastic fibers in blood vessels and lung but resulted in numerous unexpected phenotypes including bone abnormalities, hematopoietic changes, increased fat deposition, diabetes, impaired wound repair, and a bleeding diathesis. Inactivation of the gene for MAGP-2 in mice produced a neutropenia yet had minimal effects on bone or adipose homeostasis. Double knockouts had phenotypes characteristic of each individual knockout as well as several additional traits only seen when both genes are inactivated. A common mechanism underlying all of the traits associated with the knockout phenotypes is altered TGFβ signaling. This review summarizes our current understanding of the function of the MAGPs and discusses ideas related to their role in growth factor regulation.