CircPDE7B/miR-661 axis accelerates the progression of human keloid fibroblasts by upregulating fibroblast growth factor 2 (FGF2).

Circular RNAs (circRNAs) are implicated in keloidogenesis and development. We aimed to investigate the role of a new identified phosphodiesterase 7B-derived circRNA (hsa_circ_0002198; henceforth named as PDE7B) in human keloid fibroblasts (HKFs) and to further confirm its mechanism via competing endogenous RNA (ceRNA) network. Transcriptional and translational levels of circPDE7B, microRNA (miR)-661, fibroblast growth factor 2 (FGF2), cleaved caspase3, B-cell lymphoma (bcl)-2, and bcl-2-associated X protein (bax) were detected by real-time quantitative PCR and western blotting. Relationship among circPDE7B, miR-661, and FGF2 was confirmed by bioinformatics algorithm, dual-luciferase reporter assay, RNA immunoprecipitation, RNA pull-down assay, and Spearman's rank correlation analysis. Cell progression was measured by cell counting kit-8 assay, 5-ethynyl-2-deoxyuridine assay, transwell assays, and flow cytometry. Expression of circPDE7B was upregulated in human keloid tissues and HKFs, accompanied with miR-661 downregulation and FGF2 upregulation. High circPDE7B accelerated proliferation, migration, and invasion, and inhibited apoptosis. These effects were paralleled with increased bcl-2 and decreased cleaved caspase3 and bax. Moreover, low circPDE7B played opposite effects to high circPDE7B. Restoring miR-661 could suppress HKFs progression, while blocking miR-661 could facilitate that. Notably, miR-661 was directly sponged by circPDE7B and then directly governed FGF2 gene expression. Deleting miR-661 and re-expressing FGF2 both abrogated the suppression of circPDE7B knockdown in HKFs progression. In conclusion, circPDE7B might contribute to HKFs progression via functioning as ceRNA for miR-661, suggesting a novel circPDE7B/miR-661/FGF2 pathway underlying keloid formation and treatment.

Upregulation of fibroblast growth factor 2 contributes to endometriosis through SPRYs/DUSP6/ERK signaling pathway.

Previous studies report that fibroblast growth factor 2 (FGF2) modulates Sproutys (SPRYs)/dual specificity phosphatase 6 (DUSP6)/extracellular signal-regulated kinase (ERK) signaling pathway in endometrial glandular epithelial cells. However, its role in endometriosis remains unclear. The expression patterns and localization of related proteins in endometrium patients' samples were determined using quantitative reverse transcription PCR, Western blotting, and immunohistochemistry, respectively. Human endometrial stromal cells (HESCs) were isolated and transfected with small interfering RNA (siRNA) targeting FGF2 (FGF2-siRNA). Cell viability was determined using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. It was found that FGF2 mRNA and protein levels were increased in the ectopic endometrium, whilst the mRNA and protein levels of SPRYs/DUSP6/ERK signaling pathway related-genes were dysregulated. Spearman's rank correlation analysis revealed a negative correlation between FGF2 and SPRYs/DUSP6 signaling pathway-related proteins. In vitro study demonstrated that FGF2 silencing suppressed cell proliferation. Our results suggest that FGF2 upregulation might contribute to endometriosis via the regulation of the SPRYs/DUSP6/ERK signaling pathway.

The Timecourses of Functional, Morphological, and Molecular Changes Triggered by Light Exposure in Sprague-Dawley Rat Retinas.

Retinal neurodegeneration can impair visual perception at different levels, involving not only photoreceptors, which are the most metabolically active cells, but also the inner retina. Compensatory mechanisms may hide the first signs of these impairments and reduce the likelihood of receiving timely treatments. Therefore, it is essential to characterize the early critical steps in the neurodegenerative progression to design adequate therapies. This paper describes and correlates early morphological and biochemical changes in the degenerating retina with in vivo functional analysis of retinal activity and investigates the progression of neurodegenerative stages for up to 7 months. For these purposes, Sprague-Dawley rats were exposed to 1000 lux light either for different durations (12 h to 24 h) and examined seven days afterward (7d) or for a fixed duration (24 h) and monitored at various time points following the exposure (up to 210d). Flash electroretinogram (fERG) recordings were correlated with morphological and histological analyses to evaluate outer and inner retinal disruptions, gliosis, trophic factor release, and microglial activation. Twelve hours or fifteen hours of exposure to constant light led to a severe retinal dysfunction with only minor morphological changes. Therefore, early pathological signs might be hidden by compensatory mechanisms that silence retinal dysfunction, accounting for the discrepancy between photoreceptor loss and retinal functional output. The long-term analysis showed a transient functional recovery, maximum at 45 days, despite a progressive loss of photoreceptors and coincident increases in glial fibrillary acidic protein (GFAP) and basic fibroblast growth factor-2 (bFGF-2) expression. Interestingly, the progression of the disease presented different patterns in the dorsal and ventral retina. The information acquired gives us the potential to develop a specific diagnostic tool to monitor the disease's progression and treatment efficacy.

Clinical significance of miR-139-5p and FGF2 in ovarian cancer.

PURPOSE: To estimate the expression and clinical significance of miR-139-5p and fibroblast growth factor 2 (FGF2) in ovarian cancer (OC). METHODS: Of the 198 female patients undergoing surgical treatment in our hospital, 101 patients with ovarian tumor resection were allocated in a study group and 97 with ovarian resection for benign lesions were allocated in a control group. MiR-139-5p and FGF2 expression was quantified, and associations between miR-139-5p and FGF2 and clinicopathological features of OC were analyzed, as well as their diagnostic performances (receiver operating characteristic (ROC) curve). RESULTS: The study group presented lower miR-139-5p level and higher FGF2 level (both p<0.05). Significant associations of miR-139-5p and FGF2 with tumor differentiation and clinical stage were noted in OC (p<0.05). MiR-139-5p was reversely associated with clinical stage and positively associated with tumor differentiation (p<0.05), FGF2 was positively correlated with clinical stage and negatively correlated with tumor differentiation (p<0.05). The overall survival in the study group was 70.41%. The survival in high miR-139-5p expression group and low FGF2 expression group improved remarkably (p<0.05). The area under the curve (AUC) of combined detection (0.91) was higher than that of single detection. CONCLUSION: MiR-139-5p shows a decreased expression and FGF-2 shows an increased expression in OC, and they are associated with clinical stage and tumor differentiation. Combined detection of miR-139-5p and FGF-2 contributes to the diagnosis and treatment of OC, and is an available biomarker for the diagnosis and prognosis of patients.

AAV2-mediated and hypoxia response element-directed expression of bFGF in neural stem cells showed therapeutic effects on spinal cord injury in rats.

Neural stem cell (NSCs) transplantation has been one of the hot topics in the repair of spinal cord injury (SCI). Fibroblast growth factor (FGF) is considered a promising nerve injury therapy after SCI. However, owing to a hostile hypoxia condition in SCI, there remains a challenging issue in implementing these tactics to repair SCI. In this report, we used adeno-associated virus 2 (AAV2), a prototype AAV used in clinical trials for human neuron disorders, basic FGF (bFGF) gene under the regulation of hypoxia response element (HRE) was constructed and transduced into NSCs to yield AAV2-5HRE-bFGF-NSCs. Our results showed that its treatment yielded temporally increased expression of bFGF in SCI, and improved scores of functional recovery after SCI compared to vehicle control (AAV2-5HRE-NSCs) based on the analyses of the inclined plane test, Basso-Beattie-Bresnahan (BBB) scale and footprint analysis. Mechanistic studies showed that AAV2-5HRE-bFGF-NSCs treatment increased the expression of neuron-specific neuronal nuclei protein (NeuN), neuromodulin GAP43, and neurofilament protein NF200 while decreased the expression of glial fibrillary acidic protein (GFAP) as compared to the control group. Further, the expressions of autophagy-associated proteins LC3-II and Beclin 1 were decreased, whereas the expression of P62 protein was increased in AAV2-5HRE-bFGF-NSCs treatment group. Taken together, our data indicate that AAV2-5HRE-bFGF-NSCs treatment improved the recovery of SCI rats, which is accompanied by evidence of nerve regeneration, and inhibition of SCI-induced glial scar formation and cell autophagy. Thus, this study represents a step forward towards the potential use of AAV2-5HRE-bFGF-NSCs for future clinical trials of SCI repair.

Recombinant protein production-associated metabolic burden reflects anabolic constraints and reveals similarities to a carbon overfeeding response.

A comparison of the metabolic response of Escherichia coli BL21 (DE3) towards the production of human basic fibroblast growth factor (hFGF-2) or towards carbon overfeeding revealed similarities which point to constraints in anabolic pathways. Contrary to expectations, neither energy generation (e.g., ATP) nor provision of precursor molecules for nucleotides (e.g., uracil) and amino acids (e.g., pyruvate, glutamate) limit host cell and plasmid-encoded functions. Growth inhibition is assumed to occur when hampered anabolic capacities do not match with the ongoing and overwhelming carbon catabolism. Excessive carbon uptake leads to by-product secretion, for example, pyruvate, acetate, glutamate, and energy spillage, for example, accumulation and degradation of adenine nucleotides with concomitant accumulation of extracellular hypoxanthine. The cellular response towards compromised anabolic capacities involves downregulation of cAMP formation, presumably responsible for subsequently better-controlled glucose uptake and resultant accumulation of glucose in the culture medium. Growth inhibition is neglectable under conditions of reduced carbon availability when hampered anabolic capacities also match with catabolic carbon processing. The growth inhibitory effect with accompanying energy spillage, respectively, hypoxanthine secretion and cessation of cAMP formation is not unique to the production of hFGF-2 but observed during the production of other proteins and also during overexpression of genes without transcript translation.

HOXD-AS1 facilitates cell migration and invasion as an oncogenic lncRNA by competitively binding to miR-877-3p and upregulating FGF2 in human cervical cancer.

BACKGROUND: Long non-coding RNAs (LncRNAs) are dysregulated in multiple human cancers and they are highly involved in tumor progression. Previous studies have identified the oncogenic lncRNA HOXD cluster antisense RNA 1 (HOXD-AS1) in human cancers, while its roles in cervical cancer (CC) remain unclear. Herein we intended to characterize the implication of HOXD-AS1 in CC. METHODS: qRT-PCR was applied to examine the relative expression of HOXD-AS1 in CC tissues, cell lines and transfected cells. Wound healing and transwell assays were applied to detect cell migration and invasion alteration. The targeting relationship between miRNA and mRNA/lncRNA was determined by dual luciferase reporter, qRT-PCR and western blot assays. RESULTS: HOXD-AS1 was overexpressed in CC tissues and cell lines. Its higher level predicted worse prognosis of CC patients. SiRNA mediated knockdown of HOXD-AS1 repressed CC cell migration and invasion, and its overexpression did the opposite. Mechanistically, HOXD-AS1 acted as a competing endogenous RNA (ceRNA) to sponge miR-877-3p and led to upregulation of FGF2, a target of miR-877-3p. Importantly, either miR-877-3p overexpression or FGF2 inhibition could abolish the migration and invasion promotion induced by HOXD-AS1. CONCLUSION: HOXD-AS1 functions as a tumor-promoting lncRNA via the miR-877-3p/FGF2 axis in CC. HOXD-AS1 might be a promising therapeutic target as well as a novel prognostic biomarker for CC.

Pentraxin 3 inhibits fibroblast growth factor 2 induced osteoclastogenesis in rheumatoid arthritis.

BACKGROUND: Synovial fibroblasts (SFs) act as key effector cells mediating synovial inflammation and joint destruction in rheumatoid arthritis (RA). Fibroblast growth factor 2 (FGF2) and its receptors (FGFRs) play important roles in RASF-mediated osteoclastogenesis. Pentraxin 3 (PTX3) is a soluble pattern recognition receptor with nonredundant roles in inflammation and innate immunity. PTX3 is produced by various cell types, including SFs and is highly expressed in RA. However, the role of PTX3 in FGF2-induced osteoclastogenesis in RA and the underlying mechanism have been poorly elucidated. METHODS: We first determined the expression of FGF2 and RANKL in synovial tissue and synovial fluid of RA patients. We then examined the effect of PTX3 on RASF osteoclastogenesis induced by endogenous and exogenous FGF2 in isolated RASF cells treated with FGF2 and/or recombinant PTX3 (rPTX3). Thirdly, we analyzed the effect of PTX3 on FGF2 binding to FGFR-1 and HSPG receptors on RASFs. Lastly, we evaluated joint morphology after injection of rPTX3 into collagen-induced arthritis (CIA) mice. RESULTS: FGF2 was confirmed to be highly expressed in both synovial tissue and synovial fluid of RA patients. FGF2 promoted cell proliferation and increased the expressions of RANKL and ICAM-1 and RANKL/OPG to induce osteoclastogenesis in RASF, while anti-FGF2 neutralized this effect. PTX3 significantly inhibited FGF2-induced RASF cell growth and osteoclastogenesis by preventing the interaction of 125I-FGF2 and FGFRs on the same cells. In addition, administration of rPTX3 significantly ameliorated cartilage and bone destruction in mice with CIA. CONCLUSIONS: PTX3 exhibited an inhibitory effect on the autocrine and paracrine stimulation of FGF2 on SFs, and ameliorated bone destruction in CIA mice. PTX3 may be implicated in bone destruction in RA, which may provide theoretical evidence and potential therapeutic targets for RA treatment.

Enhancement of cell proliferation and motility of mammalian cells grown in co-culture with Pichia pastoris expressing recombinant human FGF-2.

Many studies examining the biological function of recombinant proteins and their effects on the physiology of mammalian cells stipulate that the proteins be purified before being used as therapeutic agents. In this study, we explored the possibility of using unpurified recombinant proteins to treat mammalian cells. The recombinant protein was used directly from the expression source and the biological function was compared to purified commercially available, equivalent protein. The model for this purpose was recombinant FGF-2, expressed by Pichia pastoris, which was used to treat the murine fibroblast cell line, NIH/3T3. We generated a P. pastoris strain (yHL11) that constitutively secreted a biologically active recombinant FGF-2 protein containing an N-terminal c-myc epitope (Myc-FGF-2). Myc-FGF-2 was then used without purification either a) in the form of conditioned mammalian cell culture medium or b) during co-cultures of yHL11 with NIH/3T3 to induce higher proliferation and motility of NIH/3T3 cells. The effects of Myc-FGF-2 on cell physiology were comparable to commercially available FGF-2. To our knowledge, this is the first time the physiology of cultured mammalian cells had been successfully altered with a recombinant protein secreted by P. pastoris while the two species shared the same medium and culture conditions. Our data demonstrated the biological activity of unpurified recombinant FGF-2 on NIH/3T3 cells and provided a foundation for directly using unpurified recombinant proteins expressed by P. pastoris with mammalian cells, potentially as wound-healing therapeutics.

MicroRNA-936 promotes proliferation and invasion of gastric cancer cells by down-regulating FGF2 expression and activating P13K/Akt signaling pathway.

OBJECTIVE: This study was designed to investigate whether microRNA-936 can be involved in the development of gastric cancer (GCa) by down-regulating FGF2 expression and activating the phosphatidylinositol 3-kinase/protein kinase B (P13K/Akt) signaling pathway. PATIENTS AND METHODS: Quantitative polymerase chain reaction (qPCR) was carried out to examine microRNA-936 and FGF2 levels in GCa tissue samples and adjacent normal ones, and further in GCa cell lines. After transfection of microRNA-936 inhibitor in GCa cell lines BGC and SGC, cell invasion, and proliferation abilities were evaluated by transwell and cell counting kit-8 (CCK-8) assays, respectively. In addition, the Dual-Luciferase reporting assay was conducted to verify the binding relationship between microRNA-936 and FGF2. After simultaneous transfection of microRNA-936 inhibitor and si-FGF2 in GCa cells, we detected the expression of FGF2/P13K/Akt by performing qPCR and Western blot experiments to further verify the regulation of microRNA-936 on FGF2 and PI3K/AKT pathway. RESULTS: QPCR detection revealed that microRNA-936 was remarkably up-regulated while FGF2 was conversely down-regulated in GCa tissue samples, indicating a negative correlation between the two. In addition, compared with normal gastric mucosal cells GES, microRNA-936 showed a significant increased expression in GCa cell lines. Meanwhile, down-regulation of microRNA-936 caused a marked reduction in invasive and proliferation ability of GCa cells. Dual-Luciferase reporting assay demonstrated a direct binding of microRNA-936 to FGF2. QPCR and Western blot showed that microRNA-936 can inhibit FGF2 expression and activate the PI3K/AKT pathway at the same time. Further studies found that silencing FGF2 induced an enhancement in cell proliferation and invasiveness, which could be reversed by simultaneous downregulation of microRNA-936. The above observations suggested that microRNA-936 may accelerate the progression of GCa by inhibiting FGF2 expression and activating the PI3K/AKT pathway. CONCLUSIONS: Overexpression of microRNA-936 can be conducive to the development of GCa, mainly through the down-regulation of FGF2 and activation of the P13K/Akt signaling pathway.

Regulation of MYO18B mRNA by a network of C19MC miRNA-520G, IFN-γ, CEBPB, p53 and bFGF in hepatocellular carcinoma.

MYO18B has been proposed to contribute to the progression of hepatocellular carcinoma (HCC). However, the signals that govern MYO18B transcription are not known. Here we show that, a network of C19MC miRNA-520G, IFN-γ, CEBPB and p53 transcriptional-defects promote MYO18B mRNA expression in HCCs. IFN-γ by itself suppresses MYO18B transcription, but promotes it when miRNA-520G is stably overexpressed. Similarly, CEBPB-liver-enriched activator protein (LAP) isoform overexpression suppresses MYO18B transcription but promotes transcription when the cells are treated with IFN-γ. Furthermore, miR-520G together with mutant-p53 promotes MYO18B transcription. Conversely, bFGF suppresses MYO18B mRNA irrespective of CEBPB, miR-520G overexpression or IFN-γ treatment. Finally high MYO18B expression reflects poor prognosis while high MYL5 or MYO1B expression reflects better survival of HCC patients. Thus, we identified a network of positive and negative regulators of MYO18B mRNA expression which reflects the survival of HCC patients.

Fermentation, purification and immunogenicity of a recombinant tumor multi-epitope vaccine, VBP3.

The recombinant multi-epitope vaccine called VBP3 is designed to suppress tumor growth and angiogenesis through targeting both basic fibroblast growth factor (bFGF) and vascular endothelial growth factor A (VEGFA). We are aiming to produce VBP3 vaccine in a large scale and provide sufficient protein for pre-clinical study. High cost and potential toxicity are severe limitations of IPTG and we investigated whether lactose can mediate VBP3 induction. Firstly, we identified the biological characteristics and established a culture bank of VBP3 strains. The best-performing strains were selected and the fermentation mode of medium, bacterial growth and protein expression were optimized in shake flasks. We scaled up the VBP3 production in 10 L bioreactor using lactose as inducer and the protein yield was comparable with IPTG induction. Next, the target protein was purified by nickel-nitrilotriacetic acid (Ni-NTA) affinity chromatography, with a SDS-PAGE purity over 90%. Further, the purified VBP3 vaccine was subcutaneously injected in BALB/c mice and elicited high-titer anti-bFGF (1:32,000) and anti-VEGFA (1:4000) antibodies. Take together, lactose was an applicable inducer for VBP3 production and the eligible product of VBP3 was harvested in the large-scale fermentation, supporting the industrial production and pre-clinical study in the future. The VBP3 vaccine with superior immunogenicity might be used as a potential therapeutic vaccine for tumor treatment.

Early growth response gene mediates in VEGF and FGF signaling as dissected by CRISPR in corpus luteum of water buffalo.

The EGR family comprises of EGR 1, EGR 2, EGR 3 and EGR 4 which are involved in the transactivation of several genes. A broad range of extracellular stimuli by growth factors is capable of activating EGR mediated transactivation of genes involved in angiogenesis and cell proliferation. However, their role in controlling VEGF A and FGF 2 signaling in the CL of water buffalo is not known. The present study was conducted to understand the role of EGR mediated regulation of VEGF A and FGF 2 signaling in buffalo luteal cells. Towards this goal, luteal cells were cultured and treated with VEGF A and FGF 2 and the mRNA expression pattern of EGR family members were documented. The EGR 1 message was found to be up-regulated in luteal cells of buffalo at 72 hours of culture. The functional validation of EGR 1 gene was accomplished by knocking out (KO) of EGR 1 in cultured luteal cells by CRISPR/Cas9 mediated gene editing technology. The EGR 1 KO cells were then cultured and stimulated with VEGF A and FGF 2. It was observed that VEGF A and FGF 2 induced angiogenesis, cell proliferation and steroidogenesis in wild type luteal cells, whereas the response of the growth factors was attenuated in the EGR 1 KO cells. Taken together our study provides evidence convincingly that both VEGF and FGF mediate their biological action through a common intermediate, EGR 1, to regulate corpus luteum function of buffalo.

In vitro biocompatibility of biohybrid polymers membrane evaluated in human gingival fibroblasts.

The biohybrid polymer membrane (BHM) is a new biomaterial designed for the treatment of soft periodontal tissue defects. We aimed to evaluate the in vitro biocompatibility of the membrane in human gingival fibroblasts and the capability to induce cell adhesion, migration, differentiation and improving the production of the extracellular matrix. BHM and Mucograft® collagen matrix (MCM) membranes were punched into 6 mm diameter round discs and placed in 96-well plates. Human primary gingival fibroblasts were seeded on the membranes or tissue culture plastic (TCP) serving as the control. Cell proliferation/viability and morphology were evaluated after 3, 7, and 14 days of culture by cell counting kit (CCK)-8 assay and scanning electron microscopy, respectively. Additionally, the gene expression of transforming growth factor (TGF)-ß1, focal adhesion kinase (FAK), collagen type 1 (Col1), alpha-smooth muscle actin (α-SMA), and fibroblasts growth factor (FGF)-2 was analyzed at 3, 7, and 14 days of culture by qPCR. Cell proliferation on BHM was significantly higher than on MCM and similar to TCP. Gene expression of TGF-ß1, FAK, Col1, and α-SMA were significantly increased on BHM compared to TCP at most investigated time points. However, the gene expression of FGF-2 was significantly decreased on BHM at Day 7 and recovered at Day 14 to the levels similar to TCP. The finding of this study showed that BHM is superior for gingival fibroblasts in terms of adhesion, proliferation, and gene expression, suggesting that this membrane may promote the healing of soft periodontal tissue.

LncRNA PCGEM1 promotes renal carcinoma progression by targeting miR-433-3p to regulate FGF2 expression.

Long non-coding RNAs (lncRNAs) are implicated in the development of carcinomas, containing renal carcinoma. The competing endogenous RNA (ceRNA) network is well-known in modulating the pathological and physiological processes of tumors. Still and all, the function role of oncogenic lncRNA PCGEM1 prostate-specific transcript (PCGEM1) in renal carcinoma was undefined till now. This paper aimed to figure out the role and mechanism of PCGEM1 in renal carcinoma. In this study, PCGEM1 was observed to be lifted in renal carcinoma cells. Loss-of-function experiments displayed that silencing of PCGEM1 repressed cell proliferation and migration, and activated apoptosis in renal carcinoma. FISH assay and subcellular fractionation assay indicated that PCGEM1 was largely located in the cytoplasm. As demonstrated, PCGEM1 interacted with microRNA433-3p (miR-433-3p). Subsequently, luciferase reporter and RIP experiments together with qRT-PCR certified that PCGEM1 and fibroblast growth factor 2 (FGF2) functioned as ceRNA for miR-433-3p, leading to the upregulation of FGF2 expression. Finally, rescue assays exhibited that FGF2 overexpression rescued the inhibited cell progression caused by PCGEM1 downregulation. MiR-433-3p inhibitor could reverse the cell growth and migration caused by PCGEM1 downregulation. The present research investigated the molecular mechanism underlying PCGEM1 in renal carcinoma, exposing a PCGEM1-mediated therapy for the treatment of patients with renal carcinoma.

Polarizing receptor activation dissociates fibroblast growth factor 2 mediated inhibition of myelination from its neuroprotective potential.

Fibroblast growth factor (FGF) signaling contributes to failure of remyelination in multiple sclerosis, but targeting this therapeutically is complicated by its functional pleiotropy. We now identify FGF2 as a factor up-regulated by astrocytes in active inflammatory lesions that disrupts myelination via FGF receptor 2 (FGFR2) mediated activation of Wingless (Wnt) signaling; pharmacological inhibition of Wnt being sufficient to abrogate inhibition of myelination by FGF2 in tissue culture. Using a novel FGFR1-selective agonist (F2 V2) generated by deleting the N-terminal 26 amino acids of FGF2 we demonstrate polarizing signal transduction to favor FGFR1 abrogates FGF mediated inhibition of myelination but retains its ability to induce expression of pro-myelinating and immunomodulatory factors that include Cd93, Lif, Il11, Hbegf, Cxcl1 and Timp1. Our data provide new insights into the mechanistic basis of remyelination failure in MS and identify selective activation of FGFR1 as a novel strategy to induce a neuroprotective signaling environment in multiple sclerosis and other neurological diseases.

Osteoblasts grown on microroughened titanium surfaces regulate angiogenic growth factor production through specific integrin receptors.

Cellular attachment and response to biomaterials are mediated by integrin receptor binding to extracellular matrix proteins adsorbed onto the material surface. Osteoblasts interact with their substrates via several integrin complexes including fibronectin-binding α5ß1 and collagen-binding α1ß1 and α2ß1. Knockdown of α2 or ß1 integrin subunits inhibits the production of factors that promote an osteogenic microenvironment, including osteocalcin, osteoprotegerin, and TGFß1. Osteoblasts also secrete several angiogenic growth factors such as VEGF-A (VEGF165), FGF-2, and angiopoietin 1, which are regulated by titanium surface topography and surface energy. Here, we examined whether signaling through integrin receptor complexes regulates production and secretion of angiogenic factors during osteoblast differentiation on microtextured Ti surfaces. To do this, integrin subunits α1, α2, α5, and ß1 were stably silenced in MG63 osteoblast-like cells cultured on grit-blasted/acid-etched hydrophobic Ti (SLA) or on hydrophilic SLA (modSLA). VEGF-A production increased in response to Ti surface topography and energy in integrin α2, α5, and ß1 silenced cells but decreased in α1-silenced cells. FGF-2 decreased on modSLA substrates in both α1 and α2-silenced cells but was unchanged in response to silencing of either α5 or ß1. In integrin α1, α2, and ß1-silenced cells, Ang-1 increased on modSLA but α5-silencing did not affect Ang-1 production during surface mediated differentiation. These results suggest that signaling through specific integrin receptor complexes during osteoblast differentiation on microstructured Ti substrates, regulates the production of angiogenic factors by those cells, and this is differentially regulated by surface hydrophilicity. STATEMENT OF SIGNIFICANCE: Successful implantation of synthetic biomaterials into bone depends on the biological process known as osseointegration. Osseointegration is a highly regulated communication of cells that orchestrates the migration of progenitor cells towards the implant site and promotes the deposition and mineralization of extracellular matrix proteins within the implant microenvironment, to tightly join the implant to native bone. In this process, angiogenesis functions as the initiation site of progenitor cell migration and is necessary for matrix deposition by providing the necessary nutrients for bone formation. In the present study, we show a novel regulation of specific angiogenic growth factors by integrin receptor complexes. This research is important to develop biomaterials that promote and maintain osseointegration through proper vascularization and prevent implant failure in patients lacking sufficient angiogenesis.

bFGF overexpression adipose derived mesenchymal stem cells improved the survival of pulmonary arterial endothelial cells via PI3k/Akt signaling pathway.

Pulmonary arterial hypertension (PAH) is characterized as pulmonary arterial endothelial dysfunction and endothelial cells over proliferation, therefore, the repair of pulmonary arterial endothelial cells has been a common goal in treating PAH. In the present study, human adipose derived mesenchymal stem cells (ASCs) were transfected with bFGF lentiviral vector and co-cultured with monocrotaline pyrrole treated human pulmonary arterial endothelial cells (HPAECs). The results showed that bFGF-ASCs improved the proliferation, viability and decreased the apoptosis of HPAECs, besides, improved PAH was observed in PAH rat models. Western blot analysis showed that the PI3k and p-Akt protein expression level increased in HPAECs, suggesting the activation of the PI3k/Akt signaling pathway. With the administration of LY294002, the bFGF induced HPAECs survival and PI3k/Akt signaling activation were successfully blocked. The present study demonstrated that bFGF transfected ASCs improved the survival of HPAECs by activating the PI3k/Akt pathway.

Extracellular matrix protein anosmin-1 modulates olfactory ensheathing cell maturation in chick olfactory bulb development.

Olfactory ensheathing cells (OECs) are a specialized class of glia, wrapping around olfactory sensory axons that target the olfactory bulb (OB) and cross the peripheral nervous system/central nervous system boundary during development and continue to do so post-natally. OEC subpopulations perform distinct subtype-specific functions dependent on their maturity status. Disrupted OEC development is thought to be associated with abnormal OB morphogenesis, leading to anosmia, a defining characteristic of Kallmann syndrome. Hence, anosmin-1 encoded by Kallmann syndrome gene (KAL-1) might modulate OEC differentiation/maturation in the OB. We performed in ovo electroporation of shRNA in the olfactory placode to knock-down kal in chick embryos, resulting in abnormal OB morphogenesis and loss of olfactory sensory axonal innervation into OB. BLBP-expressing OECs appeared to form a thinner and poorly organized outmost OB layer where SOX10 expressing OECs were completely absent with emergence of GFAP-expressing OECs. Furthermore, in embryonic day 10 chick OB explant cultures, GFAP expression in OECs accumulating along the OB nerve layers was dramatically reduced by recombinant anosmin-1. We then purified immature OECs from embryonic day 10 chick OB. These cells express GFAP after 7 days in vitro, exhibiting a multipolar morphology. Overexpression of chick anosmin, exogenous anosmin-1 or FGF2 could inhibit GFAP expression with cells presenting elongated morphology, which was blocked by the FGF receptor inhibitor Su5402. These data demonstrate that anosmin-1 functions via FGF signalling in regulating OEC maturation, thereby providing a permissive glial environment for axonal innervation into the OB during development.

circRAD18 sponges miR-208a/3164 to promote triple-negative breast cancer progression through regulating IGF1 and FGF2 expression.

As a new rising star of non-coding RNA, circular RNAs (circRNAs) emerged as vital regulators with biological functions in diverse of cancers. However, the function and precise mechanism of the vast majority of circRNAs in triple-negative breast cancer (TNBC) occurrence and progression have not been clearly elucidated. In the current study, we identified and further investigated hsa_circ_0002453 (circRAD18) by analyzing our previous microarray profiling. Expression of circRAD18 was found significantly upregulated in TNBC compared with normal mammary tissues and cell lines. circRAD18 was positively correlated with T stage, clinical stage and pathological grade and was an independent risk factor for TNBC patients. We performed proliferation, colony formation, cell migration, apoptosis and mouse xenograft assays to verify the functions of circRAD18. Knockdown of circRAD18 significantly suppressed cell proliferation and migration, promoted cell apoptosis and inhibited tumor growth in functional and xenograft experiments. Through luciferase reporter assays, we confirmed that circRAD18 acts as a sponge of miR-208a and miR-3164 and promotes TNBC progression through upregulating IGF1 and FGF2 expression. Altogether, our research revealed the pivotal role of circRAD18-miR-208a/3164-IGF1/FGF2 axis in TNBC tumorigenesis and metastasis though the mechanism of competing endogenous RNAs. Thus, circRAD18 may serve as a novel prognostic biomarker and potential target for TNBC treatment in the future.