Inhibition Of Fibroblast Growth Factor Research Articles

Intraarticular Administration of Dobesilate for the Treatment of Knee Rheumatoid Arthritis

Rheumatoid arthritis is an inflammatory condition that causes a negative effect in patient well-being. Fibroblast growth factor participates in the pathology of rheumatoid arthritis through its proliferative, inflammatory and angiogenic activities. Dobesilate, an inhibitor of fibroblast growth factor shows marked anti-proliferative, anti-inflammatory, and anti-angiogenic activities. Our study shows that intraarticular application of dobesilate is effective in reducing symptoms and signs in patients with chronic knee rheumatoid arthritis.

Inhibition of FGF signaling accelerates neural crest cell differentiation of human pluripotent stem cells

Neural crest (NC) is a transient population, arising during embryonic development and capable of differentiating into various somatic cells. The defects of neural crest development leads to neurocristopathy. Several signaling pathways were revealed their significance in NC cell specification. Fibroblast growth factor (FGF) is recognized as an important signaling during NC development, for instance Xenopus and avian; however, its contributions in human species are remained elusive. Here we used human pluripotent stem cells (hPSCs) to investigate the consequences of FGF inhibition during NC cell differentiation. The specific-FGF receptor inhibitor, SU5402, was used in this investigation. The inhibition of FGF did not found to affect the proliferation or death of hPSC-derived NC cells, but promoted hPSCs to commit NC cell fate. NC-specific genes, including PAX3, SLUG, and TWIST1, were highly upregulated, while hPSC genes, such as OCT4, and E-CAD, rapidly reduced upon FGF signaling blockage. Noteworthy, TFAP-2α, a marker of migratory NC cells, abundantly presented in SU5402-induced cells. This accelerated NC cell differentiation could be due to the activation of Notch signaling upon the blockage of ERK1/2 phosphorylation, since NICD was increased by SU5402. Altogether, this study proposed the contributions of FGF signaling in controlling human NC cell differentiation from hPSCs, the crosstalk between FGF and Notch, and might imply to the influences of FGF signaling in neurocristophatic diseases.

Endothelial cell-derived pentraxin 3 limits the vasoreparative therapeutic potential of circulating angiogenic cells.

AimsCirculating angiogenic cells (CACs) promote revascularization of ischaemic tissues although their underlying mechanism of action and the consequences of delivering varying number of these cells for therapy remain unknown. This study investigates molecular mechanisms underpinning CAC modulation of blood vessel formation.Methods and resultsCACs at low (2 × 105 cells/mL) and mid (2 × 106 cells/mL) cellular densities significantly enhanced endothelial cell tube formation in vitro, while high density (HD) CACs (2 × 107 cells/mL) significantly inhibited this angiogenic process. In vivo, Matrigel-based angiogenesis assays confirmed mid-density CACs as pro-angiogenic and HD CACs as anti-angiogenic. Secretome characterization of CAC-EC conditioned media identified pentraxin 3 (PTX3) as only present in the HD CAC-EC co-culture. Recombinant PTX3 inhibited endothelial tube formation in vitro and in vivo. Importantly, our data revealed that the anti-angiogenic effect observed in HD CAC-EC co-cultures was significantly abrogated when PTX3 bioactivity was blocked using neutralizing antibodies or PTX3 siRNA in endothelial cells. We show evidence for an endothelial source of PTX3, triggered by exposure to HD CACs. In addition, we confirmed that PTX3 inhibits fibroblast growth factor (FGF) 2-mediated angiogenesis, and that the PTX3 N-terminus, containing the FGF-binding site, is responsible for such anti-angiogenic effects.ConclusionEndothelium, when exposed to HD CACs, releases PTX3 which markedly impairs the vascular regenerative response in an autocrine manner. Therefore, CAC density and accompanying release of angiocrine PTX3 are critical considerations when using these cells as a cell therapy for ischaemic disease.

LPA1 Mediates Antidepressant-Induced ERK1/2 Signaling and Protection from Oxidative Stress in Glial Cells.

Antidepressants have been shown to affect glial cell functions and intracellular signaling through mechanisms that are still not completely understood. In the present study, we provide evidence that in glial cells the lysophosphatidic acid (LPA) receptor LPA1 mediates antidepressant-induced growth factor receptor transactivation, ERK1/2 signaling, and protection from oxidative stress. Thus, in C6 glioma cells and rat cortical astrocytes, ERK1/2 activation induced by either amitriptyline or mianserin was antagonized by Ki16425 and VPC 12249 (S), which block LPA1 and LPA3 receptors, and by AM966, which selectively blocks LPA1 Cell depletion of LPA1 with siRNA treatment markedly reduced antidepressant- and LPA-induced ERK1/2 phosphorylation. LPA1 blockade prevented antidepressant-induced phosphorylation of the transcription factors CREB and Elk-1. Antidepressants and LPA signaling to ERK1/2 was abrogated by cell treatment with pertussis toxin and by the inhibition of fibroblast growth factor (FGF) receptor (FGF-R) and platelet-derived growth factor receptor (PDGF-R) tyrosine kinases. Both Ki16425 and AM966 suppressed antidepressant-induced phosphorylation of FGF-R. Moreover, blockade of LPA1 or inhibition of FGF-R and PDGF-R activities prevented antidepressant-stimulated Akt and GSK-3β phosphorylations. Mianserin protected C6 glioma cells and astrocytes from apoptotic cell death induced by H2O2, as indicated by increased cell viability, decreased expression of cleaved caspase 3, reduced cleavage of poly-ADP ribose polymerase and inhibition of DNA fragmentation. The protective effects of mianserin were antagonized by AM966. These data indicate that LPA1 constitutes a novel molecular target of the regulatory actions of tricyclic and tetracyclic antidepressants in glial cells.

Abstract 1174: AZD4547 and AZD5363 synergistically inhibit prostate cancer progression by modulating MAPK and AKT activation

Abstract Prostate cancer (PCa) is the second most common cancer and the second most common cause of cancer mortality in men in the United States. Multiple approved therapies target the androgen signaling axis in this metastatic disease, however, after advancing to the androgen-independent stage, PCa is unresponsive to androgen ablation therapy and is refractory to further curative treatment. Recent advances have demonstrated that two intracellular signaling pathways promote prostate cancer progression, one is the Fibroblast Growth Factor (FGF) pathway included multiple FGFs and 4 kinds of FGF receptors (FGFR), which remains activated in the cancer cells, the other is the oncogenic PI3K/AKT pathway, which is constantly active due to the loss of an important tumor suppressor gene. Targeted inhibition of FGF and AKT signaling pathways has shown promising both in vitro and in vivo studies. However, FGFR or AKT inhibitor, as a single agent, would result in a reciprocal feedback loop. Therefore, it is imperative that both pathways be targeted simultaneously in the treatment of advanced prostate cancer. In this study, we evaluated the effect of combined treatment of FGFR inhibitor AZD4547 and AKT inhibitor AZD5363 on PCa progression. Proliferation assay shows that AZD4547 just weakly, or not inhibits PCa cell proliferation, AZD5363 significantly inhibits PCa cell proliferation; the combined treatment of AZD4547 and AZD5363 shows similar inhibition effect to AZD5363. Both AZD4547 and AZD5363 inhibit PCa cell anchorage-independent growth and invasion, which are synergistically decrease by the combined treatment. AZD4547 significantly inhibits phosporylation of FGFR1 and FGFR4 in PCa cells; AZD5363 increases FGFR1 and FGFR4 phosphorylation, which was significantly repressed in combined treatment. The activation of FGFR2α, MEK1/2, and Erk1/2 in PCa cells was remarkably inhibited by AZD4547 but increased by AZD5363, and synergistically inhibited by the combined treatment. AKT was hyperphosphorylated by AZD5363 and inhibited by AZD4547. The phosporylation of AKT downstream molecules PRAS40, GSK3β and S6, was slightly decreased by AZD4547 but strongly inhibited by AZD5363 and the combined treatment. Both AZD4547 and AZD5363 suppress STAT3 phosphorylation in PCa cells and the combind treatment shows synergistic inhibition effect. Both AZD4547 and AZD5363 promote AR and PTEN expression at both RNA and protein levels in VCaP and 22RV1cells, and the combination treatment remains the promotion effect. In LNCaP cells, AZD5363, but not AZD4547, stimulates AR mRNA and protein expression, which keep increased in combined treatment. This study provides a preclinical proof of concept that combination of a FGFR inhibitor with an AKT inhibitor has a profound potential to treat PCa. Acknowledgement: This project was supported by the DOD Prostate Cancer Program, PCRP-IDEA-PC120481 (Ittmann), the Prostate Cancer Foundation (Ittmann) Citation Format: Shu Feng, Michael Ittmann. AZD4547 and AZD5363 synergistically inhibit prostate cancer progression by modulating MAPK and AKT activation. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1174.

Finding Expandable Induced Cardiovascular Progenitor Cells.

Expandable Cardiovascular Progenitor Cells Reprogrammed From Fibroblasts Zhang et al Cell Stem Cell . 2016;18:368–381. Lineage Reprogramming of Fibroblasts Into Proliferative Induced Cardiac Progenitor Cells by Defined Factors Lalit et al Cell Stem Cell . 2016;18:354–367. Cardiovascular progenitor cells (CPCs) are a promising cell source for cardiac regenerative therapy because of their ability for self-renewal and differentiation into various cardiovascular cell types beneficial for myocardial repair: cardiomyocytes, smooth muscle cells, and endothelial cells. Previous evaluations of exogenously derived CPCs have focused mainly on their capacity for trilineage differentiation rather than self-renewal because of the lack of an effective protocol to maintain and expand CPCs long-term in culture. In a recent issue of Cell Stem Cell , 2 groups of investigators independently reported their success in isolating, maintaining, and expanding mouse CPCs in culture for >18 to 20 passages (1010- to 1015-fold expansion), with faithful preservation of progenitor phenotype and ability for trilineage-restricted differentiation in both cell culture and mouse models of myocardial infarction (MI). This commentary will discuss the unique findings of these 2 studies, highlight the strengths and weaknesses of each CPC derivation/expansion technique, and propose additional steps necessary to accelerate their clinical translation. The past 2 decades have witnessed some of the most dramatic developments in the field of cardiac regeneration. Central to numerous controversies is the debate on whether certain stem cell types can differentiate into functional cardiomyocytes at a clinically relevant efficiency after implantation for repair of MI. Bone marrow–derived hematopoietic stem cells1,2 and c-kit+ resident cardiac stem cells3 are 2 notable cell types at the center of contention. Although many adult stem cells can still confer modest therapeutic benefits via paracrine effects, the search for a bona fide progenitor cell type that can generate a significant …

FGFR inhibitors: Effects on cancer cells, tumor microenvironment and whole-body homeostasis (Review).

Fibroblast growth factor (FGF)2, FGF4, FGF7 and FGF20 are representative paracrine FGFs binding to heparan-sulfate proteoglycan and fibroblast growth factor receptors (FGFRs), whereas FGF19, FGF21 and FGF23 are endocrine FGFs binding to Klotho and FGFRs. FGFR1 is relatively frequently amplified and overexpressed in breast and lung cancer, and FGFR2 in gastric cancer. BCR-FGFR1, CNTRL-FGFR1, CUX1-FGFR1, FGFR1OP-FGFR1, MYO18A-FGFR1 and ZMYM2-FGFR1 fusions in myeloproliferative neoplasms are non-receptor-type FGFR kinases, whereas FGFR1-TACC1, FGFR2-AFF3, FGFR2-BICC1, FGFR2-PPHLN1, FGFR3-BAIAP2L1 and FGFR3-TACC3 fusions in solid tumors are transmembrane-type FGFRs with C-terminal alterations. AZD4547, BGJ398 (infigratinib), Debio-1347 and dovitinib are FGFR1/2/3 inhibitors; BLU9931 is a selective FGFR4 inhibitor; FIIN-2, JNJ-42756493, LY2874455 and ponatinib are pan-FGFR inhibitors. AZD4547, dovitinib and ponatinib are multi-kinase inhibitors targeting FGFRs, colony stimulating factor 1 receptor (CSF1R), vascular endothelial growth factor (VEGF)R2, and others. The tumor microenvironment consists of cancer cells and stromal/immune cells, such as cancer-associated fibroblasts (CAFs), endothelial cells, M2-type tumor-associating macrophages (M2-TAMs), myeloid-derived suppressor cells (MDSCs) and regulatory T cells. FGFR inhibitors elicit antitumor effects directly on cancer cells, as well as indirectly through the blockade of paracrine signaling. The dual inhibition of FGF and CSF1 or VEGF signaling is expected to enhance the antitumor effects through the targeting of immune evasion and angiogenesis in the tumor microenvironment. Combination therapy using tyrosine kinase inhibitors (FGFR or CSF1R inhibitors) and immune checkpoint blockers (anti-PD-1 or anti-CTLA-4 monoclonal antibodies) may be a promising choice for cancer patients. The inhibition of FGF19-FGFR4 signaling is associated with a risk of liver toxicity, whereas the activation of FGF23-FGFR4 signaling is associated with a risk of heart toxicity. Endocrine FGF signaling affects the pathophysiology of cancer patients who are prescribed FGFR inhibitors. Whole-genome sequencing is necessary for the detection of promoter/enhancer alterations of FGFR genes and rare alterations of other genes causing FGFR overexpression. To sustain the health care system in an aging society, a benefit-cost analysis should be performed with a focus on disease-free survival and the total medical cost before implementing genome-based precision medicine for cancer patients.

Sef Regulates Epithelial-Mesenchymal Transition in Breast Cancer Cells.

Sef (similar expression to fgf), also know as IL17RD, is a transmembrane protein shown to inhibit fibroblast growth factor signaling in developmental and cancer contexts; however, its role as a tumor suppressor remains to be fully elucidated. Here, we show that Sef regulates epithelial-mesenchymal transition (EMT) in breast cancer cell lines. Sef expression was highest in the normal breast epithelial cell line MCF10A, intermediate expression in MCF-7 cells and lowest in MDA-MB-231 cells. Knockdown of Sef increased the expression of genes associated with EMT, and promoted cell migration, invasion, and a fibroblastic morphology of MCF-7 cells. Overexpression of Sef inhibited the expression of EMT marker genes and inhibited cell migration and invasion in MCF-7 cells. Induction of EMT in MCF10A cells by TGF-β and TNF-α resulted in downregulation of Sef expression concomitant with upregulation of EMT gene expression and loss of epithelial morphology. Overexpression of Sef in MCF10A cells partially blocked cytokine-induced EMT. Sef was shown to block β-catenin mediated luciferase reporter activity and to cause a decrease in the nuclear localization of active β-catenin. Furthermore, Sef was shown to co-immunoprecipitate with β-catenin. In a mouse orthotopic xenograft model, Sef overexpression in MDA-MB-231 cells slowed tumor growth and reduced expression of EMT marker genes. Together, these data indicate that Sef plays a role in the negative regulation of EMT in a β-catenin dependent manner and that reduced expression of Sef in breast tumor cells may be permissive for EMT and the acquisition of a more metastatic phenotype. J. Cell. Biochem. 117: 2346-2356, 2016. © 2016 Wiley Periodicals, Inc.

Case Report: Efficacy of dobesilate in insertional Achilles tendinopathy

Achilles tendinopathy is an overuse syndrome, common among runners, with sometimes considerable negative impact on their performance, overall health, and well-being. Our report shows that local injection of an aqueous solution of the diethylammonium salt of dobesilate, an inhibitor of fibroblast growth factor with significant anti-angiogenic and anti-inflammatory effects, is effective in reducing vascular density and pain in insertional Achilles tendinopathy.

Vinorelbine and epirubicin share common features with polysialic acid and modulate neuronal and glial functions.

Polysialic acid (PSA), a large, linear glycan composed of 8 to over 100 α2,8-linked sialic acid residues, modulates development of the nervous system by enhancing cell migration, axon pathfinding, and synaptic targeting and by regulating differentiation of progenitor cells. PSA also functions in developing and adult immune systems and is a signature of many cancers. In this study we identified vinorelbine, a semi-synthetic third generation vinca alkaloid, and epirubicin, an anthracycline and 4'-epimer of doxorubicin, as PSA mimetics. Similar to PSA, vinorelbine and epirubicin bind to the PSA-specific monoclonal antibody 735 and compete with the bacterial analog of PSA, colominic acid in binding to monoclonal antibody 735. Vinorelbine and epirubicin stimulate neurite outgrowth of cerebellar neurons via the neural cell adhesion molecule, via myristoylated alanine-rich C kinase substrate, and via fibroblast growth factor receptor, signaling through Erk pathways. Furthermore, the two compounds enhance process formation of Schwann cells and migration of cerebellar neurons in culture, and reduce migration of astrocytes after injury. These novel results show that the structure and function of PSA can be mimicked by the small organic compounds vinorelbine and epirubicin, thus raising the possibility to re-target drugs used in treatment of cancers to nervous system repair. Vinorelbine and epirubicin, identified as PSA mimetics, enhance, like PSA, neuronal migration, neuritogenesis, and formation of Schwann cell processes, and reduce astrocytic migration. Ablating NCAM, inhibiting fibroblast growth factor (FGFR) receptor, or adding the effector domain of myristoylated alanine-rich C kinase substrate (MARCKS) minimize the vinorelbine and epirubicin effects, indicating that they are true PSA mimetics triggering PSA-mediated functions.

Role of microRNA‑503 in the suppression of osteosarcoma cell proliferation and migration via modulation of fibroblast growth factor 2.

The present study aimed to investigate the expression levels of microRNA (miR)‑503 in osteosarcoma (OS), as well as to assess the effects and underlying mechanisms of miR‑503 on cell proliferation, apoptosis, migration and invasion of OS cells. Reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) was used to determine the expression levels of miR‑503 in OS and adjacent normal bone tissue samples. Proliferation, apoptosis, migration and invasion assays were performed to determine the effects of miR‑503 on OS cells. The expression levels of miR‑503 were significantly decreased in OS tissue samples, as compared with normal tissue samples (P<0.0001). Upregulation of miR‑503 significantly inhibited proliferation and induced cell apoptosis, as compared with the negative controls. The results of the present study also demonstrated that miR‑503 significantly decreased the migration and invasion ability of the OS cells, which may be mediated by the inhibition of fibroblast growth factor 2 (FGF2). In conclusion, the present study demonstrated that expression of miR-503 was involved in the inhibition of cellular proliferation, and induced apoptosis of the OS cells. In addition, miR‑503 was able to inhibit the migration and invasion ability of OS cells, likely via the inhibition of FGF2 expression.

HAND2-mediated proteolysis negatively regulates the function of estrogen receptor α.

A previous study demonstrated that the progesterone‑inducible HAND2 gene product is a basic helix‑loop‑helix transcription factor and prevents mitogenic effects of estrogen receptor α (ERα) by inhibiting fibroblast growth factor signalling in mouse uteri. However, whether HAND2 directly affects the transcriptional activation function of ERα remains to be elucidated. In the present study, the physical interaction between HAND2 and ERα was investigating by performing an immunoprecipitation assay and an in vitro pull‑down assay. The results demonstrated that HAND2 and ERα interacted in a ligand‑independent manner. The in vitro pull‑down assays revealed a direct interaction between HAND2 and the amino‑terminus of ERα, termed the activation function‑1 domain. To determine the physiological significance of this interaction, the role of HAND2 as a cofactor of ERα was investigated, which revealed that HAND2 inhibited the ligand‑dependent transcriptional activation function of ERα. This result was further confirmed and the mRNA expression of vascular endothelial growth factor, an ERα‑downstream factor, was decreased by the overexpression of HAND2. This inhibition of ligand‑dependent transcriptional activation function of ERα was possibly attributed to the proteasomic degradation of ERα by HAND2. These results indicate a novel anti‑tumorigenic function of HAND2 in regulating ERα‑dependent gene expression. Considering that HAND2 is commonly hypermethylated and silenced in endometrial cancer, it is hypothesized that HAND2 may serve as a possible tumor suppressor, particularly in uterine tissue.

Adenoid cystic carcinoma: A review of recent advances, molecular targets, and clinical trials.

BackgroundAdenoid cystic carcinoma (ACC) is a rare tumor of secretory glands. In this study, recent advances in molecular characterization and in therapeutics are reviewed.MethodsA search of articles in PubMed and of abstracts from national meetings was performed regarding ACC.ResultsRecent genetic analyses found that recurrent chromosome 6:9 translocations in ACC generate an MYB:NFIB gene fusion resulting in overexpression of the MYB oncoprotein. Several other frequent mutations are recently published that may be relevant for drug development. Several trials of targeted drugs are reviewed. Some agents delay tumor progression, but tumor responses remain rare.ConclusionACCs have a characteristic chromosomal translocation, but also frequently pick up additional mutations. Clinical research is limited by the rarity and slow growth of ACC. Several ongoing trials are testing agents that inhibit fibroblast growth factor receptor signaling or other signaling pathways. Novel treatments based on the recently sequenced tumor genome are under development. © 2015 The Authors Head & Neck Published by Wiley Periodicals, Inc. 38: 620–627, 2016

Diacetyloxyl derivatization of the fibroblast growth factor inhibitor dobesilate enhances its anti-inflammatory, anti-angiogenic and anti-tumoral activities.

BackgroundDobesilate (2,5-dihydroxyphenyl sulfonate, DHPS) was recently identified as the most potent member of a family of fibroblast growth factor (FGF) inhibitors headed by gentisic acid, one of the main catabolites of aspirin. Although FGFs were first described as inducers of angiogenesis, they were soon recognized as broad spectrum mitogens. Furthermore, in the last decade these proteins have been shown to participate directly in the onset of inflammation, and their potential angiogenic activity often contributes to the inflammatory process in vivo. The aim of this work was to evaluate the anti-inflammatory, anti-angiogenic and anti-tumoral activities of the derivative of DHPS obtained by acetoxylation of its two hydroxyl groups (2,5-diacetoxyphenyl sulfonate; DAPS).MethodsAnti-inflammatory, anti-angiogenic and anti-tumoral activities of DHPS and DAPS were compared using in vivo assays of dermatitis, angiogenesis and tumorigenesis. The effects of both compounds on myeloperoxidase (MPO) and cyclooxygenase (COX) activities, cytokine production and FGF-induced fibroblast proliferation were also determined.ResultsTopical DAPS is more effective than DHPS in preventing inflammatory signs (increased vascular permeability, edema, leukocyte infiltration, MPO activation) caused by contact dermatitis induction in rat ears. DAPS, but not DHPS, effectively inhibits COX-1 and COX-2 activities. DAPS also reduces the increase in serum cytokine concentration induced by lipopolysaccharide in rats. Furthermore, DAPS displays higher in vivo efficacy than DHPS in inhibiting FGF-induced angiogenesis and heterotopic glioma progression, with demonstrated oral efficacy to combat both processes.ConclusionsBy inhibiting both FGF-signaling and COX-mediated prostaglandin synthesis, DAPS efficiently breaks the vicious circle created by the reciprocal induction of FGF and prostaglandins, which probably sustains undesirable inflammation in many circumstances. Our findings define the enhancement of anti-inflammatory, anti-angiogenic and anti-tumoral activities by diacetyloxyl derivatization of the FGF inhibitor, dobesilate.

Efficacy of Dobesilate in Allergic Rhinitis - Case Report

Allergic rhinitis is a common condition that causes a negative effect on patient well-being. Antihistamines and glucocorticoids, the first line treatments usually administered for rhinitis, are normally associated to side effects. In addition, they may show limited efficiency in controlling nasal obstruction, edema and hyperemia occurring secondary to persistent inflammation. Dobesilate, an inhibitor of fibroblast growth factor and vascular endothelial growth factor, shows a markedly anti-inflammatory activity in several inflammation-dependent diseases and inflammation models. Our study shows that nostril spray application of dobesilate for one week is effective in reducing symptoms and signs in patients with seasonal allergic rhinitis.

FGF and Notch signaling hierarchy in sensory neurogenesis (651.18)

The purpose of this study was to determine the regulatory relationship of sensory neurogenesis in the trigeminal placode between the Fibroblast Growth Factor (FGF) and Notch signaling pathways. To do this, FGF signaling was blocked cell autonomously or globally while simultaneously downregulating Notch signaling in 10‐12 somite stage Gallus gallus chick embryos. Cell autonomous FGF inhibition with global Notch downregulation significantly reduced the number of proneural cells contributing the future trigeminal ganglion (p=0.0002). A similar reduction was found with concurrent global inhibition of FGF and Notch (p&lt;0.0001). Remarkably, blocking FGF either cell autonomously or globally with simultaneous Notch downregulation reversed the effects of robust neurogenesis seen with Notch downregulation alone (p&lt;0.0001). Further, Notch downregulation for 4 or 12 hours showed no difference in the level of FGF‐receptor 4 mRNA expression when compared to controls. It did however result in a highly fragmented basal lamina, which was reversed when blocking FGF signaling. From these data, we invalidate the FGF downregulates Notch in sensory neurogenesis model and propose a mechanism for parallel regulation of FGF and Notch leading to basement membrane fragmentation and subsequent delamination of differentiating opV placode cells.Grant Funding Source: Supported by NIH/NICHD ‐ R01 HD046475

Deficiency of Sef Is Associated With Increased Postnatal Cortical Bone Mass by Regulating Runx2 Activity

Sef (similar expression to fgf genes) is a feedback inhibitor of fibroblast growth factor (FGF) signaling and functions in part by binding to FGF receptors and inhibiting their activation. Genetic studies in mice and humans indicate an important role for fibroblast growth factor signaling in bone growth and homeostasis. We, therefore, investigated whether Sef had a function role in skeletal acquisition and remodeling. Sef expression is increased during osteoblast differentiation in vitro, and LacZ staining of Sef+/- mice showed high expression of Sef in the periosteum and chondro-osseous junction of neonatal and adult mice. Mice with a global deletion of Sef showed increased cortical bone thickness, bone volume, and increased periosteal perimeter by micro-computed tomography (micro-CT). Histomorphometric analysis of cortical bone revealed a significant increase in osteoblast number. Interestingly, Sef-/- mice showed very little difference in trabecular bone by micro-CT and histomorphometry compared with wild-type mice. Bone marrow cells from Sef-/- mice grown in osteogenic medium showed increased proliferation and increased osteoblast differentiation compared with wild-type bone marrow cells. Bone marrow cells from Sef-/- mice showed enhanced FGF2-induced activation of the ERK pathway, whereas bone marrow cells from Sef transgenic mice showed decreased FGF2-induced signaling. FGF2-induced acetylation and stability of Runx2 was enhanced in Sef-/- bone marrow cells, whereas overexpression of Sef inhibited Runx2-responsive luciferase reporter activity. Bone marrow from Sef-/- mice showed enhanced hematopoietic lineage-dependent and osteoblast-dependent osteoclastogenesis and increased bone resorptive activity relative to wild-type controls in in vitro assays, whereas overexpression of Sef inhibited osteoclast differentiation. Taken together, these studies indicate that Sef has specific roles in osteoblast and osteoclast lineages and that its absence results in increased osteoblast and osteoclast activity with a net increase in cortical bone mass.

Unanticipated role of apelin: regulation of miRNA generation

Recently, a paper by Kim et al. [1] in Nature Medicine magazine in January, 2013 showed that apelin (also known as APLN) inhibits fibroblast growth factor 2 (FGF2) and FGF receptor 1 (FGFR1) expression to ameliorate pulmonary hypertension by regulating the expression of miR-424 and miR-503. This study revealed the molecular mechanism of apelin in inhibiting the process of pulmonary arterial hypertension (PAH) and discovered the role of apelin in regulating miRNA generation for the first time. miRNA functions in the transcriptional regulation of gene expression to control cellular processes. miRNA is a key regulatory factor of protein expression, but the generation and regulation mechanism of miRNA is still unclear. These novel findings bring us inspiration for further research, especially on the mechanism of miRNA generation. Experiments on revealing endogenous active substance, which regulates the generation of miRNAs or revealing miRNAs that regulate the expression of apelin, may bring more breakthroughs in the future. PAH is characterized by vascular remodeling associated with obliteration of pulmonary arterioles and formation of plexiform lesions composed of hyperproliferative endothelial and vascular smooth muscle cells. Recent studies have suggested that apelin is a novel PAH endothelial function homeostasis-related factor. Alastalo et al. [2] found that apelin expression is decreased in endothelial cells of the pulmonary hypertension. However, the exact mechanism remains poorly understood. FGF2 is highly expressed in PAH and plays an important role in the progress of PAH by promoting proliferation [3] and inhibiting apoptosis [4] in endothelial cells and smooth muscle cells. miRNA is a fundamental factor of numerous cellular events by regulating RNA modification, transcription, and translation. Current studies of miRNA showed its critical function in the development of PAH. Morphological changes of plexiform vasculopathy in the end-stage PAH lung are reflected by alterations at the miRNA level [5]. Kim et al. [1] integrated these isolated observations into a mechanism and identified the miRNA-FGF signaling axis that is apelin-dependent in the maintenance of pulmonary vascular homeostasis. Previous studies found that hypoxia induces endothelial function injury. Accumulating evidence revealed that hypoxia also induces the expression of apelin [6,7],which is reduced in PAH. Actually, apelin expression and secretion, which are strongly induced under hypoxic conditions, are the early response [7]. Mechanisms that maintain sustained expression of apelin may contribute to preventing injuries caused by hypoxia and restoring the function of endothelial cells in PAH. These findings supported the development of novel therapeutic strategies to augment apelin, as well as to inhibit FGF2 signaling. In portal vein hypertension, another vascular disease, apelin/APJ presents a novel therapeutic target. APJ antagonist F13A effectively decreased the formation of portosystemic collateral vessels [8]. In atherosclerosis (AS), increasing evidence tends to prove that apelin is a novel therapeutic target for AS [9]. Although no effective treatment for PAH is available at present, certain medicines are available to mitigate disease progression. Considering its protective effect on vasodilatory and endothelial cells, apelin may be a more efficacious target for PAH therapy. In past decades, apelin was suggested to involve in numerous physiological processes, including vasodilation, systole, salt and water balance, as well as pathophysiological processes such as high blood pressure, cancer, and so on. There must be many other undiscovered functions of apelin. The findings of the intimate relationship between apelin and miRNA provide much fresh thinking for the study of apelin. The study on miR-424 and miR-503 will help to discover additional features of apelin. Park et al. [10] found that the high expression of miR-424 and miR-503 is significantly implicated in chemoresistance and tumor progression in ovarian cancer, which probably regulates cancer stem cell processes. These results indicated that apelin probably plays a vital role in epithelial mesenchymal transition in cancers. A recent study revealed that miR-503 makes women predispose to lupus [11]. The relationship between apelin and lupus has not been explored. More evidence is required to confirm whether apelin controls the effects of miR-424 and miR-503 in the above process. There are some controversial reports of apelin/APJ effects on AS. Chun et al. [12] found that apelin decreases AS formation by blocking AngII actions in ApoE-KO mice. But Hashimoto et al. [13] Acta Biochim Biophys Sin 2013, 45: 896–898 |a The Author 2013. Published by ABBS Editorial Office in association with Oxford University Press on behalf of the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences. DOI: 10.1093/abbs/gmt090. Advance Access Publication 28 August 2013

Renal Heparan Sulfate Proteoglycans Modulate Fibroblast Growth Factor 2 Signaling in Experimental Chronic Transplant Dysfunction

Depending on the glycan structure, proteoglycans can act as coreceptors for growth factors. We hypothesized that proteoglycans and their growth factor ligands orchestrate tissue remodeling in chronic transplant dysfunction. We have previously shown perlecan to be selectively up-regulated in the glomeruli and arteries in a rat renal transplantation model. Using the same model, here we present quantitative RT-PCR profiling data on proteoglycans and growth factors from laser-microdissected glomeruli, arterial tunicae mediae, and neointimae at 12 weeks after transplantation. In glomeruli and neointimae of allografts, selective induction of the matrix heparan sulfate proteoglycan perlecan was observed, along with massive accumulation of fibroblast growth factor 2 (FGF2). Profiling the heparan sulfate polysaccharide side chains revealed conversion from a non-FGF2-binding heparan sulfate phenotype in control and isografted kidneys toward a FGF2-binding phenotype in allografts. In vitro experiments with perlecan-positive rat mesangial cells showed that FGF2-induced proliferation is dependent on sulfation and can be inhibited by exogenously added heparan sulfate. These findings indicate that matrix proteoglycans such as perlecan serve as functional docking platforms for FGF2 in chronic transplant dysfunction. We speculate that heparin-like glycomimetics could be a promising intervention to retard development of glomerulosclerosis and neointima formation in chronic transplant dysfunction.

Clinical Efficacy of Intravitreal Injection of Dobesilate for Reversing Choroidal Angiogenesis in Age-Related Macular Degeneration

Wet age-related macular degeneration is associated with chronic ischemia and inflammation that upregulate several inflammatory cytokines and growth factors, particularly vascular endothelial growth factor and fibroblast growth factor which promote the growth of choroidal neovascularization. Only with the introduction of drugs that directly inhibit the actions of vascular endothelial growth factor have ophthalmologists been able to offer patients with wet age-related macular degeneration reasonable hope for improvement of vision. However, intravitreal administration of anti-vascular endothelial growth factor drugs could be associated with unexpected ocular and systemic side effects. We present consecutive case series of 64 eyes of 64 patients with wet age-related macular degeneration treated with a single intravitreal injection of Dobesilate, a synthetic fibroblast growth factor inhibitor. The end points were the improvement from baseline visual acuity and normalization of retinal histology at 1 month. Intravitreal Dobesilate injection results in a significant improvement in functional and anatomic outcomes from the first month after injection. There were no cases of treatment-associated complications.