Bone Morphogenetic Protein Receptor Type 1A Research Articles

METTL3-induced lncRNA GBAP1 promotes hepatocellular carcinoma progression by activating BMP/SMAD pathway

BackgroundHepatocellular carcinoma (HCC) is one of the most common and challenging cancers in the world. N6-methyladenosine (m6A) modification and long non-coding RNAs (lncRNAs) play critical roles in the progression of HCC. However, there are few reports on genome-wide screening and functional annotations of m6A-methylated lncRNAs in HCC.MethodsThe expression levels of m6A methyltransferase METTL3 and the association with the prognosis in HCC were determined by RT-qPCR, public dataset platforms. Then, RNA-seq, Pearson correlation analysis, MeRIP-qPCR, RNA half-life assay, gene site-directed mutation, RIP assay and RT-qPCR analysis were employed to determine the downstream target of METTL3 in HCC. Subsequently, the expression levels and roles of lncRNA glucosylceramidase beta pseudogene 1 (GBAP1) in HCC were determined by Kaplan–meier curves, RT-qPCR, in vitro functional experiments and in vivo tumorigenesis and lung metastasis models. Then, the downstream target and pathway of GBAP1 were explored by GO biological process, KEGG pathway enrichment, luciferase reporter assay, RIP assay and rescue experiments and so on.ResultsMETTL3 was upregulated in HCC and closely related to HCC prognosis. And METTL3 induced GBAP1 expression by acting as the m6A writer of GBAP1 and IGF2BP2 worked as its m6A reader. Clinically, GBAP1 expression was significantly associated with tumor size, venous infiltration, TNM stage and prognosis of HCC, Functionally, GBAP1 promoted HCC metastasis and growth both in vitro and in vivo. Furthermore, GBAP1 acted as the molecular sponge for miR-22-3p to increase the expression of bone morphogenetic protein receptor type 1A (BMPR1A), which then activated BMP/SMAD pathway in HCC cells.ConclusionsOur findings demonstrated that METTL3-induced GBAP1 promoted migration, invasion and proliferation of HCC cells via GBAP1/miR-22-3p/BMPR1A/SMAD axis. GBAP1 could be a potential prognosis indicator and therapeutic target for HCC.

Hsa-miR-27b-5p suppresses the osteogenic and odontogenic differentiation of stem cells from human exfoliated deciduous teeth via targeting BMPR1A: An ex vivo study.

Recently, miR-27b-5p was shown to be abundantly expressed in extracellular vehicles (EVs) from the inflammatory microenvironment. This study determined the role of miR-27b-5p in regulating osteogenic and odontogenic differentiation of stem cells from human exfoliated deciduous teeth (SHEDs) and further examined the regulatory mechanism of bone morphogenetic protein receptor type-1A (BMPR1A). Characteristics of SHEDs and SHEDs-EVs derived from SHEDs were evaluated respectively. The expression of miR-27b-5p in SHEDs and EVs was detected during osteo-induction. Mechanically, SHEDs were treated with miR-27b-5p mimics or an inhibitor, and the osteogenic/odontogenic differentiation and proliferation were assessed. Bioinformatic analysis and luciferase reporter were utilized for target gene prediction and verification. Finally, BMPR1A-overexpressed plasmids were transfected into SHEDs to investigate the participation of the BMPR1A/SMAD4 pathway. Data were analyzed by Student's t- test, One-way analysis of variance and Chi-square test. MiR-27b-5p was expressed in both SHEDs and EVs and was significantly increased at the initial stage of differentiation and then decreased in a time-dependent manner (p < .01). Upregulation of miR-27b-5p significantly suppressed osteogenic/odontogenic differentiation of SHEDs and inhibited proliferation (p < .05). Whereas inhibition of miR-27b-5p enhanced the differentiation (p < .05). Dual luciferase reporter assay and pull-down assay confirmed the binding site between miR-27b-5p and BMPR1A (p < .05). The overexpression of BMPR1A rescued the effect of miR-27b-5p, while contributed to the decrease of pluripotency (p < .05). Additionally, miR-27b-5p maintained pluripotency in BMPR1A-overexpressed SHEDs (p < .05). MiR-27b-5p in SHEDs/EVs was inversely associated with differentiation and suppressed the osteogenic and odontogenic differentiation of SHEDs and maintained the pluripotency of SHEDs partly by shuttering BMPR1A-targeting BMP signaling. Theoretically, inhibition of miR-27b-5p represents a potential strategy to promote osteanagenesis and dentinogenesis. However, miR-27b-5p capsuled EVs might maintain cell pluripotency and self-renewal for non-cell-targeted therapy.

Axin2-expressing cells in the periodontal ligament are regulated by bone morphogenetic protein signalling and play a pivotal role in periodontium development.

To date, controversies still exist regarding the exact cellular origin and regulatory mechanisms of periodontium development, which hinders efforts to achieve ideal periodontal tissue regeneration. Axin2-expressing cells in the periodontal ligament (PDL) have been shown to be a novel progenitor cell population that is essential for periodontal homeostasis. In the current study, we aimed to elucidate the regulatory role of bone morphogenetic protein receptor type 1A (BMPR1A)-mediated BMP signalling in Axin2-expressing cells during periodontium development. Two strains of Axin2 gene reporter mice, Axin2lacZ/+ and Axin2CreERT2/+ ; R26RtdTomato/+ mice, were used. We next generated Axin2CreERT2/+ ; R26RDTA/+ ; R26RtdTomato/+ mice to genetically ablate of Axin2-lineage cells. Axin2CreERT2/+ ; Bmpr1afl/fl ; R26RtdTomato/+ mice were established to conditionally knock out Bmpr1a in Axin2-lineage cells. Multiple approaches, including micro-computed tomography, calcein green, and alizarin red double-labelling, scanning electron microscopy, and histological and immunostaining assays, were used to analyse periodontal phenotypes and molecular mechanisms. X-gal staining revealed that Axin2-expressing cells in the PDL were mainly distributed along the alveolar bone and cementum surface. Cell lineage tracing and cell ablation assays further demonstrated the indispensable role of Axin2-expressing cells in periodontium development. Next, we found that conditional knockout of Bmpr1a in Axin2-lineage cells led to periodontal defects, which were characterized by alveolar bone loss, impaired cementogenesis, and abnormal Sharpey's fibres. Our findings suggest that Axin2-expressing cells in the PDL are essential for periodontium development, which is regulated by BMP signalling.

Insulin receptor substrate-1 inhibits high-fat diet-induced obesity by browning of white adipose tissue through miR-503.

Genetic variation of insulin receptor substrate 1 (IRS-1) was found to modulate the insulin resistance of adipose tissues, but the underlying mechanism was not clear. To investigate how the IRS-1 was involved in the browning of white adipose tissue through miRNA, we identified a mutated Irs-1 (Irs-1-/- ) mice model and found that this mice had a reduced subcutaneous WAT (sWAT) and increased brown adipose tissue (BAT) in the interscapular region. So we isolated the bone marrow stromal cells and analyzed differentially expressed miRNAs and adipogenesis-related genes with miRNA arrays and PCR arrays. Irs-1-/- mice showed decreased miR-503 expression, but increased expression of its target, bone morphogenetic protein receptor type 1a (BMPR1a). Overexpression of miR-503 in preadipocytes downregulated BMPR1a and impaired adipogenic activity through the phosphotidylinositol 3-kinase (PI3K/Akt) pathway, while the inhibitor had the opposite effect. In both Irs-1-/- and cold-induced models, sWAT exhibited BAT features, and showed tissue-specific increased BMPR1a expression, PI3K expression, and Akt phosphorylation. Thus, our results showed that IRS-1 regulated brown preadipocyte differentiation and induced browning in sWAT through the miR-503-BMPR1a pathway, which played important roles in high-fat diet-induced obesity.

Osteitis is associated with dysregulated pro-osteoblastic activity in patients with nasal polyps.

The overlying inflammatory mucosa plays a crucial role in the initiation of osteitis; however, the molecular mechanism is unclear. The objective of this study was to explore the bone morphogenetic protein (BMP) pathway and to correlate the expression of key signaling molecules with the degree of osteitis in patients with chronic rhinosinusitis with nasal polyps (CRSwNP). Prospective experimental analysis. This was an institutional review board-approved study in which mucosal samples were obtained from sites of osteitis in CRSwNP and compared to nonosteitic healthy controls (n = 10/group). Protein expression of key BMP pathway was quantified by aptamer-based protein array and confirmed by a set of selected mRNA analyses. Degree of osteitis was assessed using both Kennedy Osteitis Score and Global Osteitis Score (GOS). Pro-osteoblastic expression of BMP7 (fold change [FC] = -1.18, P = .017) and BMP9 (FC = -1.32, P = .023), their receptors, BMP receptor type-1A (BMPR1A) (FC = -2.56, P = .005) and BMP receptor type-2 (FC = -1.28, P = .022), and two enhancers of BMP signaling pathway, the repulsive guidance molecule domain family member B (FC = -1.13, P = .008) and the chordin-like protein 1 (FC = -1.18, P = .027), were all significantly downregulated in CRSwNP. Conversely, the pro-osteoclastic factor, tartrate-resistant acid phosphatase type 5 (ACP5) (FC = 2.36, P = .001), was significantly increased in CRSwNP. GOS was inversely correlated with levels of BMP7 (r = -0.684, P = .005) and BMPR1A (r = -0.864, P = .005) and positively correlated with levels of ACP5 (r = 0.815, P = .004). The FCs among the proteins studied significantly and positively correlated with the FCs of their mRNA expression (r = 0.908, P = .002). Downregulated pro-osteoblastic mucosal BMP signaling is strongly and significantly associated with increased osteitis in CRSwNP. NA Laryngoscope, 129:E102-E109, 2019.

Osteoarthritic Extracellular RNA Biomarkers in Synovial Fluid

The molecular mechanisms influencing the initiation and progression of osteoarthritis (OA) are unclear. Therefore, current clinical management of predominately involves symptomatic treatment of end-stage diagnosed OA. Understanding the pathogenesis of OA at the pre-clinical stage may aid in both diagnostic and preventative modalities in the management of this chronic disease. PURPOSE: To determine the synovial extracellular RNA (exRNA) changes associated with OA. METHODS: Synovial fluid was collected from the injured knee of a cohort of 14 individuals (ages 15-47, 10 males and 4 females) undergoing surgical repair following ACL and/or meniscus injuries. Each knee had arthroscopically graded OA and divided the cohort into 5 individuals in the OA group (OA in >1 knee compartment) and 9 individuals in the non-OA group (OA in ≤1 knee compartment). Total exRNA was extracted from the synovial fluid collected at the time of surgery, >30 million reads generated per sample using massively parallel sequencing, and differential abundance of RNA was calculated between the two groups. RESULTS: A total of 19 protein coding exRNAs were significantly different (FDR ≤ 0.05) between the two groups: 13 increased in the OA group, 6 decreased. While no specific pathways were enriched, these genes included several genes known to influence OA pathways including ADAM12 (metalloprotease-disintegrin 12) and BMPR1A (bone morphogenetic protein receptor type 1A). In addition, 3 miRNAs were different: 2 increased, 1 decreased. One of these increased miRNAs was mir30a which has a known role in promotion of extracellular matrix degradation. CONCLUSIONS: These data suggest that the profile of extracellular RNA molecules are dysregulated arthroscopically diagnosed OA. While the specific intercellular signaling role of these exRNA are yet to be elucidated, they offer intriguing biomarkers and suggestions of dysregulated molecular pathways in OA. Changes in the genes ADAM12, BMPR1A, and mir30a suggest that exRNA markers of extracellular matrix degradation are biomarkers for the initiation and/or progression of OA. These findings have the potential clinical utility to differentiate patients at risk for the development of OA, introducing the possibility for intervention at pre-symptomatic stages.

Enrichment of Adipose-Derived Stromal Cells for BMPR1A Facilitates Enhanced Adipogenesis.

Reconstruction of soft tissue defects has traditionally relied on the use of grafts and flaps, which may be associated with variable resorption and/or significant donor site morbidity. Cell-based strategies employing adipose-derived stromal cells (ASCs), found within the stromal vascular fraction (SVF) of adipose tissue, may offer an alternative strategy for soft tissue reconstruction. In this study, we investigated the potential of a bone morphogenetic protein receptor type 1A (BMPR1A)(+) subpopulation of ASCs to enhance de novo adipogenesis. Human lipoaspirate was enzymatically digested to isolate SVF and magnetic-activated cell separation was utilized to obtain BMPR1A(+) and BMPR1A(-) cells. These cells, along with unenriched cells, were expanded in culture and evaluated for adipogenic gene expression and in vitro adipocyte formation. Cells from each group were also labeled with a green fluorescent protein (GFP) lentivirus and transplanted into the inguinal fat pads, an adipogenic niche, of immunocompromised mice to determine their potential for de novo adipogenesis. Confocal microscopy along with staining of lipid droplets and vasculature was performed to evaluate the formation of mature adipocytes by transplanted cells. In comparison to BMPR1A(-) and unenriched ASCs, BMPR1A(+) cells demonstrated significantly enhanced adipogenesis when cultured in an adipogenic differentiation medium, as evidenced by increased staining with Oil Red O and increased expression of peroxisome proliferator-activating receptor gamma (PPAR-γ) and fatty acid-binding protein 4 (FABP4). BMPR1A(+) cells also formed significantly more adipocytes in vivo, as demonstrated by quantification of GFP+ adipocytes. Minimal formation of mature adipocytes was appreciated by BMPR1A(-) cells. BMPR1A(+) ASCs show an enhanced ability for adipogenesis in vitro, as shown by gene expression and histological staining. Furthermore, within an adipogenic niche, BMPR1A(+) cells possessed an increased capacity to generate de novo fat compared to BMPR1A(-) and unenriched cells. This suggests utility for the BMPR1A(+) subpopulation in cell-based strategies for soft tissue reconstruction.

Genome-wide association study of platelet aggregation in African Americans.

BackgroundWe have previously shown that platelet aggregation has higher heritability in African Americans than European Americans. However, a genome-wide association study (GWAS) of platelet aggregation in African Americans has not been reported. We measured platelet aggregation in response to arachidonic acid, ADP, collagen, or epinephrine by optical aggregometry. The discovery cohort was 825 African Americans from the GeneSTAR study. Two replication cohorts were used: 119 African Americans from the Platelet Genes and Physiology Study and 1221 European Americans from GeneSTAR. Genotyping was conducted with Illumina 1 M arrays. For each cohort, age- and sex-adjusted linear mixed models were used to test for association between each SNP and each phenotype under an additive model.ResultsSix SNPs were significantly associated with platelet aggregation (P < 5×10−8) in the discovery sample. Of these, three SNPs in three different loci were confirmed: 1) rs12041331, in PEAR1 (platelet endothelial aggregation receptor 1), replicated in both African and European Americans for collagen- and epinephrine-induced aggregation, and in European Americans for ADP-induced aggregation; 2) rs11202221, in BMPR1A (bone morphogenetic protein receptor type1A), replicated in African Americans for ADP-induced aggregation; and 3) rs6566765 replicated in European Americans for ADP-induced aggregation. The rs11202221 and rs6566765 associations with agonist-induced platelet aggregation are novel.ConclusionsIn this first GWAS of agonist-induced platelet aggregation in African Americans, we discovered and replicated, novel associations of two variants with ADP-induced aggregation, and confirmed the association of a PEAR1 variant with multi-agonist-induced aggregation. Further study of these genes may provide novel insights into platelet biology.Electronic supplementary materialThe online version of this article (doi:10.1186/s12863-015-0217-9) contains supplementary material, which is available to authorized users.

Intrinsic multipotential mesenchymal stromal cell activity in gelatinous Heberden's nodes in osteoarthritis at clinical presentation.

IntroductionGelatinous Heberden’s nodes (HNs), also termed synovial cysts, are a common form of generalized osteoarthritis (OA). We sought to determine whether HN cases at clinical presentation contained multipotential stromal cells (MSCs) and to explore whether such cells were more closely related to bone marrow (BM) or synovial fluid (SF) MSCs by transcriptional analysis.MethodsAt clinical presentation, gelatinous material was extracted/extruded from the distal phalangeal joint of OA patients with HNs. From this, plastic adherent cells were culture-expanded for phenotypic and functional characterization and comparison with BM- and SF-MSCs. Mesenchymal related gene expression was studied by using a custom-designed TaqMan Low Density Array to determine transcriptional similarities between different MSC groups and skin fibroblasts.ResultsIn all cases, HN material produced MSC-like colonies. Adherent cultures displayed an MSC phenotype (CD29+, CD44+, CD73+, CD81+, and CD90+ and CD14- CD19-, CD31-, CD34-, CD45-, and HLADR-) and exhibited osteogenic, chondrogenic lineage differentiation but weak adipogenesis. Gene cluster analysis showed that HN-MSCs were more closely related to SF- than normal or OA BM-MSCs with significantly higher expression of synovium-related gene markers such as bone morphogenic protein 4 (BMP4), bone morphogenetic protein receptor type 1A (BMPR1A), protein/leucine-rich end leucine-rich repeat protein (PRELP), secreted frizzled-related protein 4 (SFRP4), and tumor necrosis factor alpha-induced protein 6 (TNFAIP6) (P <0.05).ConclusionsGelatinous HNs derived from hand OA at clinical presentation contain a population of MSCs that share transcriptional similarities with SF-derived MSCs. Their aberrant entrapment within the synovial cysts may impact on their normal role in joint homeostasis.

BMPR1A mutations in juvenile polyposis affect cellular localization

BackgroundJuvenile polyposis (JP) is characterized by the development of hamartomatous polyps of the gastrointestinal tract that collectively carry a significant risk of malignant transformation. Mutations in the bone morphogenetic protein receptor type 1A (BMPR1A) are known to predispose to JP. We set out to study the effect of such missense mutations on BMPR1A cellular localization. MethodsWe chose eight distinct mutations for analysis. We tagged a BMPR1A wild-type (WT) expression plasmid with green fluorescent protein on its C-terminus. Site-directed mutagenesis was used to recreate JP patient mutations from the WT–green fluorescent protein BMPR1A plasmid. We verified mutant expression vector sequences by direct sequencing. First, we transfected BMPR1A expression vectors into HEK-293T cells; then, we performed confocal microscopy to determine cellular localization. Four independent observers used a scoring system from 1 to 3 to categorize the degree of membrane versus cellular localization. ResultsOf the eight selected mutations, one was within the signaling peptide, four were within the extracellular domain, and three were within the intracellular domain. The WT BMPR1A vector had strong membrane staining, whereas all eight mutations had much less membrane and much more intracellular localization. Enzyme-linked immunosorbent assays for BMPR1A demonstrated no significant differences in protein quantities between constructs, except for one affecting the start codon. ConclusionsBone morphogenetic protein receptor type 1A missense mutations occurring in patients with JP affected cellular localization in an in vitro model. These findings suggest a mechanism by which such mutations can lead to disease by altering downstream signaling through the bone morphogenetic protein pathway.

Missense Mutations of the &lt;i&gt;BMPR1B&lt;/i&gt; (&lt;i&gt;ALK6&lt;/i&gt;) Gene in Childhood Idiopathic Pulmonary Arterial Hypertension

Mutations in the bone morphogenetic protein receptor type 2 (BMPR2) gene, the activin receptor-like kinase 1 (ALK1) gene, and SMAD8 gene have been reported in heritable pulmonary arterial hypertension (HPAH) and in idiopathic pulmonary arterial hypertension (IPAH). However, almost 30% of HPAH cases and 60-90% of IPAH cases have no mutations in those genes. This suggests that there remain unidentified genes associated with HPAH and IPAH. This study screened for mutations in endoglin, SMAD1, SMAD2, SMAD3, SMAD4, SMAD5, SMAD6, SMAD7, bone morphogenetic protein receptor type 1A (BMPR1A) and bone morphogenetic protein receptor type 1B (BMPR1B) genes in 43 IPAH patients who had no mutations in BMPR2, ALK1 and SMAD8. Two missense mutations (c.479 G>A S160N, c.1176 C>A F392L) in BMPR1B were each identified in 2 IPAH patients. Immunoblot analysis revealed that the BMPR1B F392L protein promoted SMAD8 phosphorylation. The response to BMP was analyzed using promoter-reporter activities. The transcriptional activation of the BMPR1B F392L protein with SMAD8 increased above that of wild-type BMPR1B with SMAD8, and those of BMPR1B S160N and F392L with SMAD8 and SMAD4 were each increased above those of the wild-type BMPR1B with SMAD8 and SMAD4. We identified 2 novel mutations in BMPR1B in 2 patients with IPAH. Our study suggests that BMPR1B mutations are associated with the pathogenesis of IPAH.

Gonadal structures in a fetus with complete androgen insensitivity syndrome and persistent Müllerian derivatives: comparison with normal fetal development

To report a case of complete androgen insensitivity syndrome (CAIS) with Müllerian duct persistence. Case report. Academic hospital. A case of CAIS at 20 weeks' gestational age, and three male and one female 20-week-old fetuses for comparison. DNA screening for androgen receptor (AR), antimüllerian hormone (AMH), and AMH receptor type 2 (AMHR2) gene mutations, and morphologic examination of Wolffian and Müllerian derivatives and immunohistochemistry for AMH, AMHR2, and bone morphogenetic protein receptor type 1A (BMPR1A) in aborted fetuses. Histopathologic, genetic, and immunohistochemical studies. A novel mutation of AR (D767V) was identified in the index fetus. The CAIS case showed Wolffian duct degeneration, Leydig cell hyperplasia, and normally developed Sertoli cells. No AMH and AMHR2 gene sequence alterations were observed in the CAIS case, and the uterus and vagina were developed to a similar extent as found in the normal female 20-week-old fetus. The CAIS testes expressed more abundant AMH and showed fewer AMHR2-positive peritubular mesenchymal cells than the normal male testes, but BMPR1A stained similarly. Our study indicates that testes differentiation and development as well as the expression patterns of AMH, AMHR2, and BMPR1A are independent from AR function, at least up to the second trimester. The mechanisms by which the lack of functional androgen interferes with AMH action and Müllerian duct regression remain undefined.

Germline SMAD4 or BMPR1A mutations and phenotype of juvenile polyposis.

Juvenile polyposis (JP) is an inherited condition predisposing to upper gastrointestinal (UGI) polyps and colorectal cancer. Two genes are known to predispose to JP, SMAD4 and bone morphogenetic protein receptor type 1A (BMPR1A). The object of this study was to determine the differences in phenotype of patients with SMAD4 or BMPR1A mutations (MUT+) compared with those without (MUT-). DNA was extracted from 54 JP probands and used for polymerase chain reaction of all exons of SMAD4 and BMPR1A. Products were then sequenced and analyzed for mutations. Medical record data were used to create a JP database, and statistical analysis was performed using Fisher's exact and unpaired t-tests. Nine of 54 patients had germline SMAD4 mutations, 13 had BMPR1A mutations, and 32 had neither. There were no significant differences between SMAD4+ and BMPR1A+ cases in terms of clinical factors examined, except for a family history of UGI involvement (P <.01). There was a higher prevalence of familial cases in MUT+ patients (P =.09), >10 lower gastrointestinal polyps (P =.06), and frequency of family history of gastrointestinal cancer compared with MUT- patients (P =.01). Patients with germline SMAD4 or BMPR1A mutations have a more prominent JP phenotype than those without, and SMAD4 mutations predispose to UGI polyposis.