Osteoarthritis (OA) is characterized by the gradual loss of cartilage. Sprifermin, a recombinant FGF18, is being developed as a cartilage anabolic drug. PRO-C2 is a serum marker of type II collagen ...formation and low levels have been shown to be prognostic of radiographic progression. The aim of the study was to investigate whether the patient groups with either high or low PRO-C2 levels responded differently to sprifermin.
PRO-C2 was measured in synovial fluid (SF) (n = 59) and serum samples (n = 225) from participants of the FORWARD study, a 2-year phase IIb clinical trial testing the efficacy of intra-articular (IA) sprifermin over placebo. The difference between sprifermin and placebo in respect to in change cartilage thickness (measured by quantitative (q) MRI) was analyzed in groups with either high or low (3rd vs 1st-2nd tertiles) baseline serum PRO-C2 levels.
SF levels of PRO-C2 increased over time in response to sprifermin, but not to placebo. In the placebo arm, significantly (p = 0.005) more cartilage was lost in the low vs high PRO-C2 group over the 2-year period. The contrast between sprifermin and placebo was significant (p < 0.001), ranging from 0.104 mm at week 26 to 0.229 mm at week 104 in the low PRO-C2 group. This result was not significant in the high PRO-C2 group ranging from −0.034 to 0.142.
Patients with low serum PRO-C2 levels lost more cartilage thickness over time and grew more cartilage in response to sprifermin vs a placebo when compared to patients with high PRO-C2 levels.
Immune system evasion, distance tumor metastases, and increased cell proliferation are the main reasons for the progression of non-small cell lung cancer (NSCLC) and the death of NSCLC patients. ...Dysregulation of circular RNAs plays a critical role in the progression of NSCLC; therefore, further understanding the biological mechanisms of abnormally expressed circRNAs is critical to discovering novel, promising therapeutic targets for NSCLC treatment.
The expression of circular RNA fibroblast growth factor receptor 1 (circFGFR1) in NSCLC tissues, paired nontumor tissues, and cell lines was detected by RT-qPCR. The role of circFGFR1 in NSCLC progression was assessed both in vitro by CCK-8, clonal formation, wound healing, and Matrigel Transwell assays and in vivo by a subcutaneous tumor mouse assay. In vivo circRNA precipitation, RNA immunoprecipitation, and luciferase reporter assays were performed to explore the interaction between circFGFR1 and miR-381-3p.
Here, we report that circFGFR1 is upregulated in NSCLC tissues, and circFGFR1 expression is associated with deleterious clinicopathological characteristics and poor prognoses for NSCLC patients. Forced circFGFR1 expression promoted the migration, invasion, proliferation, and immune evasion of NSCLC cells. Mechanistically, circFGFR1 could directly interact with miR-381-3p and subsequently act as a miRNA sponge to upregulate the expression of the miR-381-3p target gene C-X-C motif chemokine receptor 4 (CXCR4), which promoted NSCLC progression and resistance to anti-programmed cell death 1 (PD-1)- based therapy.
Taken together, our results suggest the critical role of circFGFR1 in the proliferation, migration, invasion, and immune evasion abilities of NSCLC cells and provide a new perspective on circRNAs during NSCLC progression.
Voltage-gated sodium channels (Nav1.1–Nav1.9) are responsible for the initiation and propagation of action potentials in neurons, controlling firing patterns, synaptic transmission and plasticity of ...the brain circuit. Yet, it is the protein–protein interactions of the macromolecular complex that exert diverse modulatory actions on the channel, dictating its ultimate functional outcome. Despite the fundamental role of Nav channels in the brain, information on its proteome is still lacking. Here we used affinity purification from crude membrane extracts of whole brain followed by quantitative high-resolution mass spectrometry to resolve the identity of Nav1.2 protein interactors. Of the identified putative protein interactors, fibroblast growth factor 12 (FGF12), a member of the nonsecreted intracellular FGF family, exhibited 30-fold enrichment in Nav1.2 purifications compared with other identified proteins. Using confocal microscopy, we visualized native FGF12 in the brain tissue and confirmed that FGF12 forms a complex with Nav1.2 channels at the axonal initial segment, the subcellular specialized domain of neurons required for action potential initiation. Co-immunoprecipitation studies in a heterologous expression system validate Nav1.2 and FGF12 as interactors, whereas patch-clamp electrophysiology reveals that FGF12 acts synergistically with CaMKII, a known kinase regulator of Nav channels, to modulate Nav1.2-encoded currents. In the presence of CaMKII inhibitors we found that FGF12 produces a bidirectional shift in the voltage-dependence of activation (more depolarized) and the steady-state inactivation (more hyperpolarized) of Nav1.2, increasing the channel availability. Although providing the first characterization of the Nav1.2 CNS proteome, we identify FGF12 as a new functionally relevant interactor. Our studies will provide invaluable information to parse out the molecular determinant underlying neuronal excitability and plasticity, and extending the relevance of iFGFs signaling in the normal and diseased brain.
New neurons are generated in the postnatal rodent hypothalamus, with a subset of tanycytes in the third ventricular (3V) wall serving as neural stem/progenitor cells. However, the precise stem cell ...niche organization, the intermediate steps and the endogenous regulators of postnatal hypothalamic neurogenesis remain elusive. Quantitative lineage-tracing
revealed that conditional deletion of fibroblast growth factor 10 (Fgf10) from Fgf10-expressing β-tanycytes at postnatal days (P)4-5 results in the generation of significantly more parenchymal cells by P28, composed mostly of ventromedial and dorsomedial neurons and some glial cells, which persist into adulthood. A closer scrutiny
and
revealed that the 3V wall is not static and is amenable to cell movements. Furthermore, normally β-tanycytes give rise to parenchymal cells via an intermediate population of α-tanycytes with transient amplifying cell characteristics. Loss of Fgf10 temporarily attenuates the amplification of β-tanycytes but also appears to delay the exit of their α-tanycyte descendants from the germinal 3V wall. Our findings suggest that transience of cells through the α-tanycyte domain is a key feature, and Fgf10 is a negative regulator of postnatal hypothalamic neurogenesis.
Although stem cells from mice deficient of FGF2 have been reported to display enhanced capacity for adipogenesis, the literature using in vitro cell culture system has so far reported conflicting ...results on the role of FGF2 in adipogenesis. We here demonstrate that FGF2, depending on concentration, can function as either a positive or negative factor of in vitro adipogenesis by regulating activation of the ERK signaling pathway. FGF2 at concentrations lower than 2 ng/ml enhanced in vitro adipogenesis of human adipose-derived stem cells (hASCs). However, FGF2 at concentrations higher than 10 ng/ml was able to suppress adipogenesis by maintaining sustained phosphorylation of ERK and function as a dominant negative adipogenic factor toward BMP ligands. Expression levels of FGF2 in the fat tissues from high fat diet induced obese C57BL/6 mice were lower than those from normal chow diet mice, indicating that expression levels of FGF2 in the fat tissues might be in reverse correlation with the size of fat tissues. Our observation of concentration dependent biphasic effect as well as dominant negative effect of FGF2 on adipogenesis provides a mechanistic basis to understand roles of FGF2 in adipogenesis and development of fat tissues.
The epithelial-mesenchymal signaling involving SHH-FOXF1, TBX4-FGF10, and TBX2 pathways is an essential transcriptional network operating during early lung organogenesis. However, precise regulatory ...interactions between different genes and proteins in this pathway are incompletely understood.
To identify TBX2 and TBX4 genome-wide binding sites, we performed chromatin immunoprecipitation followed by next-generation sequencing (ChIP-seq) in human fetal lung fibroblasts IMR-90.
We identified 14,322 and 1,862 sites strongly-enriched for binding of TBX2 and TBX4, respectively, 43.95% and 18.79% of which are located in the gene promoter regions. Gene Ontology, pathway enrichment, and DNA binding motif analyses revealed a number of overrepresented cues and transcription factor binding motifs relevant for lung branching that can be transcriptionally regulated by TBX2 and/or TBX4. In addition, TBX2 and TBX4 binding sites were found enriched around and within FOXF1 and its antisense long noncoding RNA FENDRR, indicating that the TBX4-FGF10 cascade may directly interact with the SHH-FOXF1 signaling.
We highlight the complexity of transcriptional network driven by TBX2 and TBX4 and show that disruption of this crosstalk during morphogenesis can play a substantial role in etiology of lung developmental disorders.
The biological effects of different wavelengths of light emitting diode (LED) light tend to vary from each other. Research into use of photobiomodulation for treatment of skin wounds and the ...underlying mechanisms has been largely lacking. We explored the histopathological basis of the therapeutic effect of photobiomodulation and the relation between duration of exposure and photobiomodulation effect of different wavelengths of LED in a Japanese big-ear white rabbit skin-wound model. Skin wound model was established in 16 rabbits (three wounds per rabbit: one served as control, the other two wounds were irradiated by red and blue LED lights, respectively). Rabbits were then divided into 2 equal groups based on the duration of exposure to LED lights (15 and 30 min/exposure). The number of wounds that showed healing and the percentage of healed wound area were recorded. Histopathological examination and skin expression levels of fibroblast growth factor (FGF), epidermal growth factor (EGF), endothelial marker (CD31), proliferating cell nuclear antigen (Ki67) and macrophagocyte (CD68) infiltration, and the proliferation of skin collagen fibers was assessed. On days 16 and 17 of irradiation, the healing rates in red (15 min and 30 min) and blue (15 min and 30 min) groups were 50%, 37.5%, 25% and 37.5%, respectively, while the healing rate in the control group was 12.5%. The percentage healed area in the red light groups was significantly higher than those in other groups. Collagen fiber and skin thickness were significantly increased in both red light groups; expression of EGF, FGF, CD31 and Ki67 in the red light groups was significantly higher than those in other groups; the expression of FGF in red (30 min) group was not significantly different from that in the blue light and control groups. The effect of blue light on wound healing was poorer than that of red light. Red light appeared to hasten wound healing by promoting fibrous tissue, epidermal and endothelial cell proliferation. An increase in the exposure time to 30 min did not confer any additional benefit in both red and blue light groups. This study provides a theoretical basis for the potential therapeutic application of LED light in clinical settings.
Growth factor therapy is an emerging treatment modality that enhances tissue vascularization, promotes healing and regeneration and can treat a variety of inflammatory diseases. Both recombinant ...human growth factor proteins and their gene therapy are in human clinical trials to heal chronic wounds. As platelet-derived growth factor-bb (PDGF-BB) and fibroblast growth factor-2 (FGF-2) are known to induce chemotaxis, proliferation, differentiation, and matrix synthesis, we investigated a non-viral means for gene delivery of these factors using the cationic polysaccharide chitosan. Chitosan is a polymer of glucosamine and N-acetyl-glucosamine, in which the percentage of the residues that are glucosamine is called the degree of deacetylation (DDA). The purpose of this study was to express PDGF-BB and FGF-2 genes in mice using chitosan-plasmid DNA nanoparticles for the controlled delivery of genetic material in a specific, efficient, and safe manner. PDGF-BB and FGF-2 genes were amplified from human tissues by RT-PCR. To increase the secretion of FGF-2, a recombinant 4sFGF-2 was constructed bearing eight amino-acid residues of the signal peptide of FGF-4. PCR products were inserted into the expression vector pVax1 to produce recombinant plasmids pVax1-4sFGF2 and pVax1-PDGF-BB, which were then injected into BALB/C mice in the format of polyelectrolyte nanocomplexes with specific chitosans of controlled DDA and molecular weight, including 92-10, 80-10, and 80-80 (DDA-number average molecular weight or M(n) in kDa). ELISA assays on mice sera showed that recombinant FGF-2 and PDGF-BB proteins were efficiently expressed and specific antibodies to these proteins could be identified in sera of injected mice, but with levels that were clearly dependent on the specific chitosan used. We found high DDA low molecular weight chitosans to be efficient protein expressors with minimal or no generation of neutralizing antibodies, while lowering DDA resulted in greater antibody levels and correspondingly lower levels of detected recombinant protein. Histological analyses corroborated these results by revealing greater inflammatory infiltrates in lower DDA chitosans, which produced higher antibody titers. We found, in general, a more efficient delivery of the plasmids by subcutaneous than by intramuscular injection. Specific chitosan carriers were identified to be either efficient non-toxic therapeutic protein delivery systems or vectors for DNA vaccines.
In rodents, fibroblast growth factor 21 (FGF21) has emerged as a key metabolic regulator produced by liver. To gather preliminary data on the potential importance of FGF1, co-regulated genes, and ...upstream metabolic genes, we examined the hepatic mRNA expression in response to nutrition and inflammation in dairy cows. In experiment 1, induction of ketosis through feed restriction on d 5 postpartum upregulated FGF21, its co-receptor KLB, and PPARA but only elicited a numerical increase in serum FGF21 concentration. In experiment 2, cows in control (CON) or receiving 50 g/d of L-carnitine (C50) from -14 through 21 d had increased FGF21, PPARA, and NFIL3 on d 10 compared with d 2 postpartum. In contrast, compared with CON and C50, 100 g/d L-carnitine (C100) resulted in lower FGF21, KLB, ANGPTL4, and ARNTL expression on d 10. In experiment 3, cows were fed during the dry period either a higher-energy (OVE; 1.62 Mcal/kg DM) or lower-energy (CON; 1.34 Mcal/kg DM) diet and received 0 (OVE:N, CON:N) or 200 μg of LPS (OVE:Y, CON:Y) into the mammary gland at d 7 postpartum. For FGF21 mRNA expression in CON, the LPS challenge (CON:Y) prevented a decrease in expression between d 7 and 14 postpartum such that cows in CON:N had a 4-fold lower expression on d 14 compared with d 7. The inflammatory stimulus induced by LPS in CON:Y resulted in upregulation of PPARA on d 14 to a similar level as cows in OVE:N. In OVE:Y, expression of PPARA was lower than CON:N on d 7 and remained unchanged on d 14. On d 7, LPS led to a 4-fold greater serum FGF21 only in OVE but not in CON cows. In fact, OVE:Y reached the same serum FGF21 concentration as CON:N, suggesting a carryover effect of dietary energy level on signaling mechanisms within liver. Overall, results indicate that nutrition, ketosis, and inflammation during the peripartal period can alter hepatic FGF21, co-regulated genes, and upstream metabolic genes to various extents. The functional outcome of these changes merits further study, and in particular the mechanisms regulating transcription in response to changes in energy balance and feed intake.
Abnormalities of striatal function have been implicated in several major neurological and psychiatric disorders, including Parkinson's disease, schizophrenia and depression. Adenosine, via activation ...of A(2A) receptors, antagonizes dopamine signaling at D2 receptors and A(2A) receptor antagonists have been tested as therapeutic agents for Parkinson's disease. We found a direct physical interaction between the G protein-coupled A(2A) receptor (A(2A)R) and the receptor tyrosine kinase fibroblast growth factor receptor (FGFR). Concomitant activation of these two classes of receptors, but not individual activation of either one alone, caused a robust activation of the MAPK/ERK pathway, differentiation and neurite extension of PC12 cells, spine morphogenesis in primary neuronal cultures, and cortico-striatal plasticity that was induced by a previously unknown A(2A)R/FGFR-dependent mechanism. The discovery of a direct physical interaction between the A(2A) and FGF receptors and the robust physiological consequences of this association shed light on the mechanism underlying FGF functions as a co-transmitter and open new avenues for therapeutic interventions.
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