Over-expression of fibroblast growth factor receptor 3 in human hepatocellular carcinoma

AIM: To describe the significant over-expression of fibroblast growth factor receptor 3 (FGFR3), which is a signal transduction and cell proliferation related gene in hepatocellular carcinoma (HCC).METHODS: Following DNA microarray, Northern blot and quantitative real-time PCR were employed to confirm FGFR3 expression difference in HCC tissues and surrounding non-neoplastic liver tissue. FGFR3 expression levels were further determined by immunohistochemical study in 43 cases of HCC.RESULTS: Northern blot results showed the significant over-expression of FGFR3 in HCC tissues, which was consistent with that from DNA microarray. Quantitative real-time PCR demonstrated that the mean ratio of FGFR3 mRNA to glyceraldehyde-3-phosphate dehydrogenase (GADPH) mRNA in HCC tissue was 0.250, whereas the ratio in non-neoplastic liver tissue was 0.014. Statistical analyses of 43 cases of HCC revealed that HCC scored higher than the matched non-neoplastic liver tissues.Examination of clinicopathological features revealed a strong correlation of over-expression of FGFR3 with poor tumor differentiation and high nuclear grade.CONCLUSION: Over-expression of FGFR3 may play an important role in liver carcinogenesis. FGFR3 may be an ideal candidate as a molecular marker in the diagnosis of HCC and a potential therapeutic target.

Basic Fibroblast Growth Factor and Fibroblast Growth Factor Receptor-1 in Human Meningiomas

The expression of basic fibroblast growth factor (bFGF) and fibroblast growth factor receptor-1 (FGFR-1) in human meningiomas and the relationships between their expression and the tumors' histological features and angiogenesis were investigated by means of immunohistochemical technique. The expression of bFGF and FGFR-1 was detected by antibody of bFGF or FGFR-1. The tumors' angiogenesis was evaluated by microvascular density (MVD) and, which was observed by use of CD34-antibody immunohistochemically. The results showed that there were varied degrees of the expression of bFGF and FGFR-1 proteins in meningiomas. The expression was correlated with the tumors' histological characters and angiogenesis. It was concluded that bFGF and FGFR-1 might play important roles in meningiomas' angiogenesis and proliferation. The expression positive rate of bFGF and FGFR-1 may provide an indication of evaluating the histological and malignant degree of the tumor.

Fibroblast growth factor receptor 3 effects on proliferation and telomerase activity in sheep growth plate chondrocytes

Background： Fibroblast growth factor receptor 3 （FGFR3） inhibits growth-plate chondrocyte proliferation and limits bone elongation. Gain-of-function FGFR3 mutations cause dwarfism, reduced telomerase activity and shorter telomeres in growth plate chondroyctes suggesting that FGFR3 reduces proliferative capacity, inhibits telomerase, and enhances senescence. Thyroid hormone （1-3） plays a role in cellular maturation of growth plate chondrocytes and a known target of T3 is FGFR3. The present study addressed whether reduced FGFR3 expression enhanced telomerase activity, mRNA expression of telomerase reverse transcriptase （TERT） and RNA component of telomerase （TR）, and chondrocyte proliferation, and whether the stimulation of FGFR3 by T3 evoked the opposite response. Results： Sheep growth-plate proliferative zone chondrocytes were cultured and transfected with siRNA to reduce FGFR3 expression; FGFR3 siRNA reduced chondrocyte FGFR3 mRNA and protein resulting in greater proliferation and increased TERT mRNA expression and telomerase activity （p 〈 0.0.5）. Chondrocytes treated with T3 significantly enhanced FGFR3 mRNA and protein expression and reduced telomerase activity （p 〈 0.05）; TERT and TR were not significantly reduced. The action of T3 at the growth plate may be partially mediated through the FGFR3 pathway. Conclusions： The results suggest that FGFR3 inhibits chondrocyte proliferation and reducing telomerase activity indicating an important role for telomerase in capacity during bone elongation. by down-regulating TERT expression sustaining chondrocyte proliferative

Role of fibroblast growth factor receptor 1 in the bone development and skeletal diseases

Accumulating data suggest that FGFs/FGFR1 plays essential roles in the bone development and human skeletal diseases. Conditional inactivation of fgfrl caused different phenotypes displaying in different cells or specific organs and revealed some novel functions of FGFR1 in bone development. Fgfrl mutation mainly induced 2 types of human skeletal diseases, craniosynostosis syndrome and dysplasias. Similar mutation of fgfrl in mouse model just mimicked the phenotype that happened in human. These fa- cilitate the investigation on the underlying mechanism of the diseases. Here we mainly focused on the ad- vance of FGFR1 function in the bone development and its mutation caused skeletal diseases.

Are there fibroblast growth factor receptor 1 mutations in a Chinese Kallmann syndrome family?

The present study examined 58 members of a Kallmann syndrome family and investigated whether there are fibroblast growth factor receptor 1 （FGFR1） gene mutations in this family. Genomic DNA from the proband and family members was subjected to PCR to amplify 18 exons of FGFR1, and the amplified products were sequenced to identify potential mutations. MRI of the olfactory bulb region was performed on suspected subjects. The patient and his father were diagnosed with Kallmann syndrome. A polymorphic site was found at 39542, with the proband and his parents being heterozygous （guanine ＋ cytosine）. However, healthy controls and the other members of this family were homozygous for guanine at this position.

EXPRESSION AND SIGNIFICANCE OF BASIC FIBROBLAST GWOWTH FACTOR AND FIBROBLAST GROWTH FACTOR RECEPTOR-1 IN OVARIAN EPITHELIAL NEOPLASM

Objective To study the relevance of expression of basic fibroblast growth factor (bFGF), fibroblast growth factor receptor 1 (FGFR 1) and carcinogenesis and progression of ovarian epithelial neoplasm. Methods Ten cases of normal ovarian tissues and 75 cases of ovarian epithelial neoplasm tissues were detected by immunohistochemical methods: S P for bFGF, FGFR 1,double immunohistochemistry Lab SA for Ki 67 antigen and bFGF. Results The expression level of bFGF, FGFR 1in ovarian epithelium and ovarian epithelial neoplasm showed a step wise increase in the following order:normal <benign <borderline <malignant; The expression level and intensity of bFGF and FGFR 1 were increased with the decrease of differentiation degree and increase of clinical stage in ovarian carcinoma; There was no statistical difference between the expression of bFGF, FGFR 1 in serous cystadenocarcinoma and that of mucinous cystadenocarcinoma; The expression of bFGF was correlated with that of FGFR 1 in neoplastic tissues; There were positive expression rates of bFGF and Ki 67 antigen in ovarian epithelial neoplasm. Conclusion As an important proliferative factor, bFGF plays an important role in carcinogenisis and progression of ovarian epithelial neoplasm.

Expression of fibroblast growth factor-2 and fibroblast growth factor receptor-1 protein in the hippocampus in rats exhibiting chronic stress-induced depression

There is evidence that the expression of members of the fibroblast growth factor （FGF） protein family is altered in post-mortem brains of humans suffering from major depressive disorder. The present study examined whether the expression of fibroblast growth factor-2 （FGF2） and fibroblast growth factor receptor-1 （FGFR1） protein is altered following chronic stress in an animal model. Rats were exposed to 35 days of chronic unpredictable mild stress, and then tested using open-field and sucrose consumption tests. Compared with the control group, rats in the chronic stress group exhibited obvious depressive-like behaviors, including anhedonia, anxiety and decreased mobility. The results of western blot analysis and immunohistochemical analysis revealed a downregulation of the expression of FGF2 and FGFR1 in the hippocampus of rats, particularly in the CA1, CA3 and dentate gyrus. This decreased expression is in accord with the results of post-mortem studies in humans with major depressive disorder. These findings suggest that FGF2 and FGFR1 proteins participate in the pathophysiology of depressive-like behavior, and may play an important role in the mechanism of chronic stress-induced depression.

Fibroblast growth factor receptor signaling as therapeutic targets in gastric cancer

Fibroblast growth factor receptors(FGFRs) regulate a variety of cellular functions, from embryogenesis to adult tissue homeostasis. FGFR signaling also plays significant roles in the proliferation, invasion, and survival of several types of tumor cells. FGFR-induced alterations, including gene amplification, chromosomal translocation, and mutations, have been shown to be associated with the tumor initiation and progression of gastric cancer, especially in diffuse-type cancers. Therefore, the FGFR signaling pathway might be one of the therapeutic targets in gastric cancer. This review aims to provide an overview of the role of FGFR signaling in tumorigenesis, tumor progression, proliferation, and chemoresistance. We also discuss the accumulating evidence that demonstrates the effectiveness of using clinical therapeutic agents to inhibit FGFR signaling for the treatment of gastric cancer.

Fibroblast growth factor receptor 4 Gly388Arg polymorphism in Chinese gastric cancer patients

AIM: To investigate the contribution of the fibroblast growth factor receptor 4 (FGFR4) Gly388Arg polymorphism as a genetic risk factor for gastric cancer (GC) and to investigate any associations between this polymorphism and clinicopathological parameters and survival. METHODS: Tumors and matched adjacent non-cancer tissues were collected from 304 GC patients, and 5 mL of venous blood was collected from 62 GC patients and 392 ageand sex-matched healthy controls without cancer history from the same ethnic population. DNA was extracted, and direct sequencing analyses were performed to genotype the FGFR4 Gly388Arg polymorphism in all the samples. Differences in the genotype frequencies of the FGFR4 Gly388Arg polymorphism between GC patients and healthy controls were estimated using the χ 2 test. Binary logistic regression was used for all analysis variables to estimate risk as the ORs with 95%CIs. The relationships between the FGFR4 genotype and clinicopathological parameters were tested with the χ 2 test. The Kaplan-Meier product-limit method, the log-rank test, and the Cox regression model were applied to evaluate the effect of the FGFR4 genotype on the overall survival of patients with GC. RESULTS: In the present GC cohort, 118 patients (38.8%) were homozygous for the Gly388 allele, 124 patients (40.8%) were heterozygous, and 62 patients (20.4%) were homozygous for the Arg388 allele. The frequencies of the Gly/Gly, Gly/Arg, and Arg/Arg genotypes in the healthy controls were 33.6%, 48.0%, and 18.4%, respectively. The distributions of genotypes (χ 2 = 3.589, P = 0.166) and alleles (χ 2 = 0.342, P = 0.559) of the FGFR4 Gly388Arg polymorphism were not different between the GC patients and the healthy controls. Although we observed no correlation between the FGFR4 Gly388Arg polymorphism and clinicopathological parameters or survival in the total cohort of GC patients, the presence of the Arg388 allele was associated with shorter survival time in patients with GC if the tumor was small (log rank χ 2 = 5.449, P = 0.020), well differentiated (log rank χ 2 = 12.798, P = 0.000), T1 or T2 stage (log rank χ 2 = 4.745, P = 0.029), without lymph node involvement (log rank χ 2 = 6.647, P = 0.010), and at an early clinical stage (log rank χ 2 = 4.615, P = 0.032). CONCLUSION: Our results suggest that the FGFR4 Gly388Arg polymorphism is not a risk factor for GC cancer initiation but that it is a useful prognostic marker for GC patients when the tumor is relatively small, well differentiated, or at an early clinical stage.

Emodin regulating excision repair cross-complementation group 1 through fibroblast growth factor receptor 2 signaling

AIM: To investigate the molecular mechanisms underlying the reversal effect of emodin on platinum resistance in hepatocellular carcinoma. METHODS: After the addition of 10 μmol/L emodin to HepG2/oxaliplatin (OXA) cells, the inhibition rate (IR), 50% inhibitory concentration (IC 50 ) and reversal index (IC 50 in experimental group/IC 50 in control group) were calculated. For HepG2, HepG2/OXA, HepG2/OXA/T, each cell line was divided into a control group, OXA group, OXA + fibroblast growth factor 7 (FGF7) group and OXA + emodin group, and the final concentrations of FGF7, emodin and OXA in each group were 5 ng/mL, 10 μg/mL and 10 μmol/L, respectively. Single-cell gel electrophoresis was conducted to detect DNA damage, and the fibroblast growth factor receptor 2 (FGFR2), phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2) and excision repair cross-complementing gene 1 (ERCC1) protein expression levels in each group were examined by Western blotting. RESULTS: Compared with the IC50 of 120.78 μmol/L in HepG2/OXA cells, the IC 50 decreased to 39.65 μmol/L after treatment with 10 μmol/L emodin; thus, the reversal index was 3.05. Compared with the control group, the tail length and Olive tail length in the OXA group, OXA + FGF7 group and OXA + emodin group were significantly increased, and the differences were statistically significant (P < 0.01). The tail length and Olive tail length were lower in the OXA + FGF7 group than in the OXA group, and this difference was also statistically significant. Compared with the OXA + FGF7 group, the tail extent, the Olive tail moment and the percentage of tail DNA were significantly increased in the OXA + emodin group, and these differences were statistically significant (P < 0.01). In comparison with its parental cell line HepG2, the HepG2/OXA cells demonstrated significantly increased FGFR2, p-ERK1/2 and ERCC1 expression levels, whereas the expression of all three molecules was significantly inhibited in HepG2/ OXA/T cells, in which FGFR2 was silenced by FGFR2 shRNA. In the examined HepG2 cells, the FGFR2, p-ERK1/2 and ERCC1 expression levels demonstrated increasing trends in the OXA group and OXA + FGF7 group. Compared with the OXA group and OXA + FGF7 group, the FGFR2, p-ERK1/2, and ERCC1 expression levels were significantly lower in the OXA + emodin group, and these differences were statistically significant. In the HepG2/OXA/T cell line that was transfected with FGFR2 shRNA, the FGFR2, p-ERK1/2 and ERCC1 expression levels were significantly inhibited, but there were no significant differences in these expression levels among the OXA, OXA + FGF7 and OXA + emodin groups. CONCLUSION: Emodin markedly reversed OXA resistance by enhancing OXA DNA damage in HepG2/OXA cells, and the molecular mechanism was related to the inhibitory effect on ERCC1 expression being mediated by the FGFR2/ERK1/2 signaling pathway.

Fibroblast growth factor receptor 4 protein expression and clinicopathological features in gastric cancer

AIM:To investigate fibroblast growth factor receptor4(FGFR4)protein expression in Chinese patients with resectable gastric cancer(GC)and the association with clinicopathological characteristics and survival.who underwent curative surgical procedures were enrolled in this study.The protein expression of FGFR4 in formalin-fixed,paraffin-embedded(FFPE)GC tissues was determined by immunohistochemical(IHC)analysis.Patient clinicopathological data and survival information were also collected andχ2 statistical analysis was performed to analyze FGFR4 protein expression in the subgroups with differing clinicopathological characteristics including;gender,age,tumor location,differentiation,tumor-node-metastasis stage,macroscopic type,depth of invasion,lymph node metastases,distant metastasis,neural invasion and vascular invasion.Furthermore,some common molecular markers of GC in our cancer center,including p53,p27,topoisomeraseⅡα(TopoⅡα)were also determined by IHC and their association with FGFR4 protein expression evaluated.The probability of survival for different subgroups with different clinicopathological characteristics was calculated using the Kaplan-Meier method and survival curves plotted using the log rank test.RESULTS:Seventy seven cases(44%)were found to have high expression of FGFR4 protein.Significantly different FGFR4 expression was observed between gastric cancers with differing expression of TopoⅡα(log rankχ2=9.4760,P=0.0236).No significant differences were observed between subgroups defined by any of the other clinicopathological characteristics.The median survival time of the FGFR4 high expression(77 cases)and low expression groups(98 cases)was27 mo and 39 mo,respectively.The five-year survival rates and median survival times of gastric cancers with high FGFR4 expression were worse than those with low expression(30.8%vs 39.2%,27 mo vs 39 mo),respectively,however,no significant difference was observed in survival time(log rankχ2=1.0477,P=0.3060).Survival analysis revealed that high expression of FGFR4 was a predictor of poor outcome in GC patients if the tumor was small(less than or equal to 3cm in size)(log rankχ2=5.5033,P=0.0190),well dif-ferentiated(log rankχ2=7.9757,P=0.0047),and of T1 or T2 stage invasion depth(log rankχ2=4.8827,P=0.0271).CONCLUSION:Our results suggest that high tumor expression of FGFR4 protein is not an independent risk factor for GC cancer initiation,but is a useful prognostic marker for GC patients when the tumor is relatively small,well differentiated,or in the early stages of invasion.

Fibroblast growth factor receptor 4 single nucleotide polymorphism Gly388Arg in head and neck carcinomas

BACKGROUND Head and neck squamous cell carcinoma(HNSCC) is considered to be a progressive disease resulting from alterations in multiple genes regulating cell proliferation and differentiation like receptor tyrosine kinases(RTKs) and members of the fibroblast growth factor receptors(FGFR)-family. Singlenucleotide polymorphism(SNP) Arg388 of the FGFR4 is associated with a reduced overall survival in patients with cancers of various types. We speculate that FGFR4 expression and SNP is associated with worse survival in patients with HSNCC.AIM To investigate the potential clinical significance of FGFR4 Arg388 in the context of tumors arising in HNSCC, a comprehensive analysis of FGFR4 receptor expression and genotype in tumor tissues and correlated results with patients' clinical data in a large cohort of patients with HNSCC was conducted.METHODS Surgical specimens from 284 patients with HNSCC were retrieved from the Institute of Pathology at the Ludwig-Maximilian-University in Germany.Specimens were analyzed using immunohistochemistry and polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP). The expression of FGFR4 was analyzed in 284 surgical specimens of HNSCC using immunohistochemstry. FGFR4 polymorphism was detected by PCR-RFLP.Patients' clinical data with a minimum follow-up of 5 years were statistically evaluated with a special emphasis on survival analysis employing Kaplan-Meier estimator and Cox regression analysis.RESULTS Concerning the invasive tumor areas the intensity of the FGFR4 expression was evaluated in a four-grade system: no expression, low expression, intermediate and high expression. FGFR4 expression was scored as "high"(+++) in 74(26%),"intermediate"(++) in 103(36.3%), and "low"(+) in 107(36.7%) cases. Analyzing the FGFR4 mutation it was found in 96 tumors(33.8%), 84 of them(29.6%) having a heterozygous and 12(4.2%) homozygous mutated Arg388 allele. The overall frequency concerning the mutant alleles demonstrated 65% vs 34% mutated alleles in general. FGFR4 Arg388 was significantly associated with advanced tumor stage(P < 0.004), local metastasis(P < 0.0001) and reduced disease-free survival(P < 0.01). Furthermore, increased expression of FGFR4 correlated significantly with worse overall survival(P < 0.003).CONCLUSION In conclusion, the FGFR4 Arg388 genotype and protein expression of FGFR4 impacts tumor progression in patients with HNSCC and may present a useful target within a multimodal therapeutic intervention.

Fibroblast Growth Factor Receptor 1 Gene Amplification in Nonsmall Cell Lung Cancer

Objective： To review the prevalence and prognostic significance of fibroblast growth factor receptor 1 （FGFRI） amplification and to establish an association between FGFRI amplification and the clinical characteristics of nonsmall cell lung cancer （NSCLC）. Data Sources： We searched PubMed for English-language studies published between January 2010 and May 2016. Study Selection： We included all relevant articles, with no limitation of study design. Results： FGFRI amplification was reported in 8.7-20.0% of NSCLC cases and was significantly more frequent in squamous cell carcinomas （SCCs） （9.7-28.3%） than in adenocarcinomas （ADCs） （0-15.0%）. The rates of FGFRI amplification were as follows： males, 13.9-22.1%; females, 0-20.1%; Stage 1 NSCLC, 9.3-24.1%; Stage II NSCLC, 12.9-25.0%; Stage 111 NSCLC, 8.2-19.5%： Stage IV NSCLC, 0-12.5%; current smokers, 13.3-29.0%; former smokers, 2.5-23.0%; and nonsmokers, 0-22.2%. Overall survival was 43.9-70.8 months in patients with FGFRI amplification and 42.4-115.0 months in patients with no FGFRI amplification; disease-free survival was 22.5-58.5 months and 52.4-94.6 months, respectively. Conclusions： FGFR1 amplification is more frequent in SCCs than in ADCs. The association between FGFRI amplification and clinical characteristics （gender, smoking status, and disease stage） and the prognostic significance of FGFRI amplification in NSCLC remain controversial.

Mechanisms of acquired resistance to fibroblast growth factor receptor targeted therapy

Oncogenic activation of the fibroblast growth factor receptor(FGFR)through mutations and fusions of the FGFR gene occur in a variety of different malignancies such as urothelial carcinoma and cholangiocarcinoma.Inhibition of the kinase domain of the FGFR with targeted oral FGFR inhibitors has been shown in both preclinical and early phase clinical trials to lead to meaningful reductions in tumour size and larger confirmatory randomized trials are underway.Acquired resistance to FGFR inhibition using a variety of mechanisms that includes,activation of alternate signaling pathways and expansion of tumour clones with gatekeeper mutations in the FGFR gene.This review summarizes the acquired resistance mechanisms to FGFR therapy and therapeutic approaches to circumventing resistance.

Role of Insulin-like Growth Factor II Receptor in Transdifferentiation of Free Silica-induced Primary Rat Lung Fibroblasts

Objective To study the role of insulin-like growth factor II receptor in free silica-induced transdifferentiation of primary rat lung fibroblasts Methods Rat lung fibroblasts and rat alveolar macrophages were cultured. A transdifferentiation model of primary rat lung fibroblasts was induced by free silica. Levels of a-SMA protein, IGF-liR protein and mRNA were measured by immunocytochemistry, Western blot and RT-PCR, respectively. Lung fibroblasts were treated with Wortmannin. Results The expression levels of a-SMA concentration and decreased after Wortmann and IGF-IIR increased with the increasing free silica n was used. Conclusion The IGF-IIR plays an important role in free silica-induced transdifferentiation of primary rat lung fibroblasts.

Effect of Ligustrazine on Expressions of Basic Fibroblast Growth Factor and Its Receptor in Bone Marrow of Mice with Acute Radiation Injury

Objective: To study the expressions of basic fibroblast growth factor (bFGF) and its receptor (bFGFR) in bone marrow of mice with acute radiation injury, and to evaluate the effect of Ligustrazine (Lt) on them. Methods: Fifty-six Kunming mice of clean grade were randomly divided into 3 groups, the normal group, the control group and the Lt group. Mice in the latter two groups were once homogeneously systemic irradiated with 6.0 Gy of 60 Co, with the absorption dose rate of 0. 56 Gy/min, then treated with saline (0.2 ml/ mice) or Lt (2 mg/mice) respectively, twice a day through gastrogavage for successive 13 days. Mice were sacrificed in batch on the 3rd, 7th and 14th day by cervical dislocation to collect the bilateral femoral bone marrow for preparing bone marrow mono-nuclear cell (BMMNC) suspension. The bFGFR expression on surface of BMMNC was determined by flow cytometry; and the bFGF expres-sion level in one side of femoral bone marrow tissue was detected by immunohistochemistry with SABC-AP assay. Results: The bFGF expression in bone marrow of mice on the 3rd, 7th and 14th day after acute radiation injury all were significantly lower than that of the normal mice (P<0.05 or P<0.01). The expressions of bFGF and bFGFR in the Lt group detected were significantly higher than that in the control group detected at the corresponding time points (P<0.05 or P < 0.01). Conclusion:By way of enhancing bFGF expression in bone marrow and bFGFR expression on surface of BMMNC to accelerate the repairing of hemopoietic micro-environment in bone marrow might be one of the mechanisms of Lt in promoting hemopoietic function reconstitution after acute radiation injury.Original article on CJITWM (Chin) 2004;24(5):439

Fibroblast growth factor signaling in non-alcoholic fatty liver disease and non-alcoholic steatohepatitis:Paving the way to hepatocellular carcinoma

Metabolic disorders are increasingly leading to non-alcoholic fatty liver disease,subsequent steatohepatitis,cirrhosis and hepatocellular carcinoma.Fibroblast growth factors and their receptors play an important role in maintaining metabolic homeostasis also in the liver and disorders in signaling have been identified to contribute to those pathophysiologic conditions leading to hepatic lipid accumulation and chronic inflammation.While specific and well tolerated inhibitors of fibroblast growth factor receptor activity are currently developed for(non-liver)cancer therapy,treatment of non-alcoholic fatty liver disease and nonalcoholic steatohepatitis is still limited.Fibroblast growth factor-mimicking or restoring approaches have recently evolved as a novel therapeutic option and the impact of such interactions with the fibroblast growth factor receptor signaling network during non-alcoholic fatty liver disease/non-alcoholic steatohepatitis development is reviewed here.

Distribution and localization of fibroblast growth factor-8 in rat brain and nerve cells during neural stem/progenitor cell differentiation

The present study explored the distribution and localization of fibroblast growth factor-8 and its potential receptor, fibroblast growth factor receptor-3, in adult rat brain in vivo and in nerve cells during differentiation of neural stem/progenitor cells in vitro. Immunohistochemistry was used to examine the distribution of fibroblast growth factor-8 in adult rat brain in vivo. Localization of fibroblast growth factor-8 and fibroblast growth factor receptor-3 in cells during neural stem/progenitor cell differentiation in vitro was detected by immunofluorescence. Flow cytometry and immunofluorescence were used to evaluate the effect of an anti-fibroblast growth factor-8 antibody on neural stem/progenitor cell differentiation and expansion in vitro. Results from this study confirmed that fibroblast growth factor-8 was mainly distributed in adult midbrain, namely the substantia nigra, compact part, dorsal tier, substantia nigra and reticular part, but was not detected in the forebrain comprising the caudate putamen and striatum. Unusual results were obtained in retrosplenial locations of adult rat brain. We found that fibroblast growth factor-8 and fibroblast growth factor receptor-3 were distributed on the cell membrane and in the cytoplasm of nerve cells using immunohistochemistry and immunofluorescence analyses. We considered that the distribution of fibroblast growth factor-8 and fibroblast growth factor receptor-3 in neural cells corresponded to the characteristics of fibroblast growth factor-8, a secretory factor. Addition of an anti-fibroblast growth factor-8 antibody to cultures significantly affected the rate of expansion and differentiation of neural stem/progenitor cells. In contrast, addition of recombinant fibroblast growth factor-8 to differentiation medium promoted neural stem/progenitor cell differentiation and increased the final yields of dopaminergic neurons and total neurons. Our study may help delineate the important roles of fibroblast growth factor-8 in brain activities and neural stem/progenitor cell differentiation.

Basic fibroblast growth factor increases the numbe of endogenous neural stem cells and inhibits the expression of amino methyl isoxazole propionic acid receptors in amyotrophic lateral sclerosis mice

This study aimed to investigate the number of amino methyl isoxazole propionic acid （AMPA） receptors and production of endogenous neural stem cells in the SOD1 G93AG1H transgenic mouse model of amyotrophic lateral sclerosis, at postnatal day 60 following administration of basic fibroblast growth factor （FGF-2）. A radioligand binding assay and immunohistochemistry were used to estimate the number of AMPA receptors and endogenous neural stem cells respectively. Results showed that the number of AMPA receptors and endogenous neural stem cells in the brain stem and sensorimotor cortex were significantly increased, while motor function was significantly decreased at postnatal days 90 and 120. After administration of FGF-2 into mice, numbers of endogenous neural stem cells increased, while expression of AMPA receptors decreased, whilst motor functions were recovered. At postnatal day 120, the number of AMPA receptors was negatively correlated with the number of endogenous neural stem cells in model mice and FGF-2-treated mice. Our experimental findings indicate that FGF-2 can inhibit AMPA receptors and increase the number of endogenous neural stem cells, thus repairing neural injury in amyotrophic lateral sclerosis mice.

成纤维细胞生长因子受体1,2在小鼠肾发育中的动态表达

背景:在肾发育过程中,成纤维细胞生长因子受体1,2的时空表达仍是一个有争议的问题,且其与肾脏发育的关系尚不清楚。目的:观察成纤维细胞生长因子受体1,2在小鼠肾发育过程中的动态表达,探求它们与肾发生发育的关系。方法:培育不同发育阶段的胎鼠(E12,14,16,18 d)和仔鼠(N1,3,7,14,24,40 d),应用免疫组织化学技术观察成纤维细胞生长因子受体1,2在不同肾组织中的时空表达,结合体视学和Western blot对它们的表达进行定量分析。结果与结论:①免疫组化显示:在E12 d时,成纤维细胞生长因子受体1主要定位在输尿管芽尖端的生后肾组织,随后表达在各期未成熟的肾小体、部分远曲小管和毛细血管袢,反应部位主要集中在生肾区;而成纤维细胞生长因子受体2开始即在输尿管芽和生后肾组织中均有表达,随着后肾发育,定位于未发育成熟的各期肾小体、远端小管、集合管和髓袢细段,成熟肾小体表达微弱;②体视学和Western blot检测显示:成纤维细胞生长因子受体1在生前表达较高,出生后逐渐下降,N7 d后表达很低;成纤维细胞生长因子受体2在肾脏的表达随着胚(日)龄的增加而升高,N7 d后趋于稳定;③结果表明:在肾的发育过程中,成纤维细胞生长因子受体1,2呈一定的时空性表达,推测二者可能参与了肾单位的发育与成熟,而在输尿管芽分支和形态的形成过程中,成纤维细胞生长因子受体2的作用更为显著。