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HGF
Terms modified by HGF Selected AbstractsInsulin-like growth factors, hepatocyte growth factor and transforming growth factor-, in mouse tongue myogenesisDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 1 2003Akira Yamane Many reports have shown that tongue striated muscles have several unique characteristics not found in other skeletal muscles such as limb and trunk. Several peptide growth factors are reported to play important roles in skeletal myogenesis. In this article, the roles of insulin-like growth factors (IGF), hepatocyte growth factor (HGF) and transforming growth factor (TGF)-, in mouse tongue myogenesis were studied using an organ culture system of the mandible or tongue obtained from mouse embryos. It was found that IGF-I promotes the differentiation of tongue myoblasts. HGF plays an essential role in the migration and proliferation of tongue myogenic cells, and inhibits the differentiation of tongue myoblasts. TGF-, does not play an essential role in the proliferation of tongue myogenic cells, but does promote the early differentiation of tongue myoblasts. The role of IGF-I in the differentiation of tongue myoblasts, and that of HGF in the migration, proliferation and differentiation of tongue myogenic cells appear to be almost identical to their roles in the myogenesis of limb and cultured myogenic cell lines. However, the role of TGF-, in the proliferation and differentiation of tongue myogenic cells appears to be different from its role in the myogenesis of limb and cultured myogenic cell lines such as C2 and L6. [source] HGF induction of postsynaptic specializations at the neuromuscular junctionDEVELOPMENTAL NEUROBIOLOGY, Issue 2 2006Raghavan Madhavan Abstract A critical event in the formation of vertebrate neuromuscular junctions (NMJs) is the postsynaptic clustering of acetylcholine receptors (AChRs) in muscle. AChR clustering is triggered by the activation of MuSK, a muscle-specific tyrosine kinase that is part of the functional receptor for agrin, a nerve-derived heparan sulfate proteoglycan (HSPG). At the NMJ, heparan sulfate (HS)-binding growth factors and their receptors are also localized but their involvement in postsynaptic signaling is poorly understood. In this study we found that hepatocyte growth factor (HGF), an HS-binding growth factor, surrounded muscle fibers and was localized at NMJs in rat muscle sections. In cultured Xenopus muscle cells, HGF was enriched at spontaneously occurring AChR clusters (hot spots), where HSPGs were also concentrated, and, following stimulation of muscle cells by agrin or cocultured neurons, HGF associated with newly formed AChR clusters. HGF presented locally to cultured muscle cells by latex beads induced new AChR clusters and dispersed AChR hot spots, and HGF beads also clustered phosphotyrosine, activated c-Met, and proteins of dystrophin complex; clustering of AChRs and associated proteins by HGF beads required actin polymerization. Lastly, although bath-applied HGF alone did not induce new AChR clusters, addition of HGF potentiated agrin-dependent AChR clustering in muscle. Our findings suggest that HGF promotes AChR clustering and synaptogenic signaling in muscle during NMJ development. © 2005 Wiley Periodicals, Inc. J Neurobiol, 2005 [source] Comparison of the effects of HGF, BDNF, CT-1, CNTF, and the branchial arches on the growth of embryonic cranial motor neuronsDEVELOPMENTAL NEUROBIOLOGY, Issue 2 2002Arifa Naeem Abstract In the developing embryo, axon growth and guidance depend on cues that include diffusible molecules. We have shown previously that the branchial arches and hepatocyte growth factor (HGF) are growth-promoting and chemoattractant for young embryonic cranial motor axons. HGF is produced in the branchial arches of the embryo, but a number of lines of evidence suggest that HGF is unlikely to be the only factor involved in the growth and guidance of these axons. Here we investigate whether other neurotrophic factors could be involved in the growth of young cranial motor neurons in explant cultures. We find that brain-derived neurotrophic factor (BDNF), ciliary neurotrophic factor (CNTF) and cardiotrophin-1 (CT-1) all promote the outgrowth of embryonic cranial motor neurons, while glial cell line-derived neurotrophic factor (GDNF) and neurotrophin-3 (NT-3) fail to affect outgrowth. We next examined whether HGF and the branchial arches had similar effects on motor neuron subpopulations at different axial levels. Our results show that HGF acts as a generalized rather than a specific neurotrophic factor and guidance cue for cranial motor neurons. Although the branchial arches also had general growth-promoting effects on all motor neuron subpopulations, they chemoattracted different axial levels differentially, with motor neurons from the caudal hindbrain showing the most striking response. © 2002 Wiley Periodicals, Inc. J Neurobiol 51: 101,114, 2002 [source] Hepatocyte growth factor is a significant risk factor for white matter lesions in Japanese type 2 diabetic patientsEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 7 2010Futoshi Anan Eur J Clin Invest 2010; 40 (7): 585,590 Abstract Background, The presence of white matter lesions (WML) is an important prognostic factor for the development of stroke. Elevated hepatocyte growth factor (HGF) levels are associated with a high mortality rate in type 2 diabetic patients. The preliminary study was therefore designed to test the hypothesis that the presence of WML correlates with HGF and insulin resistance in type 2 diabetic patients not receiving insulin treatment. Material and methods, Based on brain magnetic resonance imaging, 92 type 2 diabetic patients were divided into two groups: WML-positive group (age 60 ± 5 years, mean ± SD, n = 35) and WML-negative group (age 59 ± 6 years, mean ± SD, n = 57. The level of blood glucose was assessed by fasting plasma glucose, fasting immunoreactive insulin, homeostasis model assessment (HOMA) index and haemoglobin A1c (HbA1c). Results, The body mass index was higher in the WML-positive group than that in the WML-negative group (P < 0·005). Plasma levels of triglycerides were higher while high-density lipoprotein cholesterol was lower in the WML-positive group than in the WML-negative group (P < 0·01 and P < 0·0001 respectively). Fasting plasma glucose (P < 0·0001), insulin concentrations (P < 0·0001), HOMA index (P < 0·0001) and HGF (< 0·0001) levels were higher in the WML-positive group than in the WML-negative group. Multivariate logistic analysis revealed that WML was independently predicted by the high HGF and insulin resistance (P < 0·0001 and P < 0·0001 respectively). Conclusion, The results of this preliminary study indicate that the presence of WML was associated with the high HGF and insulin resistance in Japanese patients with type 2 diabetes mellitus. [source] High serum hepatocyte growth factor level in patients with non-Hodgkin's lymphomaEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 5 2003Liang-Tsai Hsiao Abstract: Higher pretreatment serum hepatocyte growth factor (HGF) levels were observed in patients with multiple myeloma and Hodgkin's disease, but not in those with non-Hodgkin's lymphoma (NHL). We examined patients' serum levels at diagnosis using enzyme-linked immunosorbent assay and histological expression of HGF in pathological specimens of lymphoma, in relation to clinical features. The subjects were 77 NHL patients and 40 healthy controls. The serum levels of HGF in NHL patients at diagnosis were significantly higher than those in healthy controls (median 1019 vs. 689 pg/mL, P < 0.001). At diagnosis, patients with more than two sites of extranodal involvement (P = 0.001), higher scores of international prognostic index (P = 0.015), and advanced Ann Arbor stage (P = 0.023) had a higher level of serum HGF. Although the association of pretreatment serum HGF level and survival was not significant, a correlation of serial change of serum HGF levels with treatment response was found in limited cases. Furthermore, HGF expression of lymphoma tissues was shown in 18 of 24 (75%) different NHL subtypes, including most of the diffuse large B cell lymphoma (12 of 15, 80%). In conclusion, our study showed higher pretreatment serum HGF levels in NHL patients, which was related to clinical features; and the serial change of HGF seemed to parallel the treatment response. The pathogenic role of HGF in NHL patients was further highlighted by a modest expression of HGF in most of the diffuse large B cell lymphoma. [source] Macrophage-stimulating protein is a neurotrophic factor for embryonic chicken hypoglossal motoneuronsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2002Oliver Schmidt Abstract Macrophage-stimulating protein (MSP) exerts a variety of biological actions on many cell types, but has no known functions in the brain. MSP is structurally related to hepatocyte growth factor (HGF), another pleiotropic factor whose many functions include promoting neuronal survival and growth. To investigate whether MSP is also capable of acting as a neurotrophic factor, we purified hypoglossal motoneurons from the embryonic chicken hindbrain because these neurons are known to express the MSP receptor tyrosine kinase RON. MSP promoted the in vitro survival of these neurons during the period of naturally occurring neuronal death and enhanced the growth of neurites from these neurons. MSP mRNA was detected in the developing tongue whose musculature is innervated by hypoglossal neurons. Our study demonstrates that MSP is a neurotrophic factor for a population of developing motoneurons. [source] Expression of c-Met in developing rat hippocampus: evidence for HGF as a neurotrophic factor for calbindin D-expressing neuronsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 10 2000Laura Korhonen Abstract Hepatocyte growth factor-scatter factor (HGF) is expressed in different parts of the nervous system, and has been shown to exhibit neurotrophic activity. Here we show that c-Met, the receptor for HGF, is expressed in developing rat hippocampus, with the highest levels during the first postnatal weeks. To study the function of HGF, hippocampal neurons were prepared from embryonic rats and treated with different HGF concentrations. In these cultures, HGF increased the number of neurons expressing the 28-kDa calcium-binding protein (calbindin D) in a dose-dependent manner. The effect of HGF was larger than that observed with either brain-derived neurotrophic factor (BDNF) or neurotrophin-3 (NT-3), and cotreatment of the cultures with HGF and the neurotrophins was additive with respect to calbindin D neurons. Besides affecting the number of neurons, HGF significantly increased the degree of sprouting of calbindin D-positive neurons, suggesting an influence on neuronal maturation. BDNF and NT-3 stimulated neurite outgrowth of calbindin D neurons to a much smaller degree. In contrast to calbindin D neurons, HGF did not significantly increase the number of neurons immunoreactive with the neurotransmitter ,-aminobutyric acid (GABA) in the hippocampal cultures. Immunohistochemical studies showed that c-Met-, calbindin D- and HGF-immunoreactive cells are all present in the dentate gyrus and partly colocalize within neurons. These results show that HGF acts on calbindin D-containing hippocampal neurons and increases their neurite outgrowth, suggesting that HGF plays an important role for the maturation and function of these neurons in the hippocampus. [source] Expression and mutational analysis of MET in human solid cancersGENES, CHROMOSOMES AND CANCER, Issue 12 2008Patrick C. Ma MET receptor tyrosine kinase and its ligand hepatocyte growth factor (HGF) regulate a variety of cellular functions, many of which can be dysregulated in human cancers. Activated MET signaling can lead to cell motility and scattering, angiogenesis, proliferation, branching morphogenesis, invasion, and eventual metastasis. We performed systematic analysis of the expression of the MET receptor and its ligand HGF in tumor tissue microarrays (TMA) from human solid cancers. Standard immunohistochemistry (IHC) and a computerized automated scoring system were used. DNA sequencing for MET mutations in both nonkinase and kinase domains was also performed. MET was differentially overexpressed in human solid cancers. The ligand HGF was widely expressed in both tumors, primarily intratumoral, and nonmalignant tissues. The MET/HGF likely is functional and may be activated in autocrine fashion in vivo. MET and stem cell factor (SCF) were found to be positively stained in the bronchioalevolar junctions of lung tumors. A number of novel mutations of MET were identified, particularly in the extracellular semaphorin domain and the juxtamembrane domain. MET-HGF pathway can be assayed in TMAs and is often overexpressed in a wide variety of human solid cancers. MET can be activated through overexpression, mutation, or autocrine signaling in malignant cells. Mutations in the nonkinase regions of MET might play an important role in tumorigenesis and tumor progression. MET would be an important therapeutic antitumor target to be inhibited, and in lung cancer, MET may represent a cancer early progenitor cell marker. © 2008 Wiley-Liss, Inc. [source] Molecular dissection of the chromosome band 7q21 amplicon in gastroesophageal junction adenocarcinomas identifies cyclin-dependent kinase 6 at both genomic and protein expression levelsGENES, CHROMOSOMES AND CANCER, Issue 8 2008H. van Dekken Amplification of chromosome band 7q21 has been frequently detected in various types of cancer including gastroesophageal junction (GEJ) adenocarcinomas. At present, no gene has been disclosed that can explain this frequent amplification of 7q21 in GEJ carcinomas. Therefore, a detailed genomic analysis of the 7q21 region was performed on a selected series of GEJ adenocarcinomas, i.e., 14 primary adenocarcinomas and 10 cell lines, by array comparative genomic hybridization (aCGH) with a 7q11.22-q31.2 contig array. A distinct peak of amplification was identified at 92.1 Mb in 7q21.2, precisely comprising cyclin-dependent kinase 6 (CDK6), a gene involved in cell cycle regulation. A smaller peak was seen at 116.2 Mb in 7q31.2, the locus of the MET proto-oncogene. No distinct peak was detected for the hepatocyte growth factor (HGF) at 81.3 Mb in 7q21.11. An immunoprofile of HGF, CDK6 and MET revealed a strong correlation between aCGH and immunohistochemical protein expression for CDK6 (P = 0.002). Furthermore, immunohistochemistry did not show expression of CDK6 in Barrett's dysplasia and carcinoma in situ, correlating expression of CDK6 with a malignant phenotype. We conclude that high-resolution genomic analysis and immunoprofiling identify CDK6 as the main candidate target for the recurrent amplification of 7q21 in GEJ adenocarcinomas. © 2008 Wiley-Liss, Inc. [source] Small molecule c-MET inhibitor PHA665752: Effect on cell growth and motility in papillary thyroid carcinomaHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 8 2008Chandrani Chattopadhyay PhD Abstract Background c-Met is upregulated in papillary thyroid carcinoma (PTC) and can be an attractive therapeutic target. We tested the effects of the small molecule c-met inhibitor PHA665752 in blocking c-met,dependent phenotypic effects in PTC cell lines. Methods PTC patient tissues and cell lines were evaluated for c-met expression. The effect of PHA665752 on c-met phosphorylation, downstream signaling, hepatocyte growth factor (HGF),dependent cell growth, and induction of apoptosis was studied. The IC50 of PHA665752 in c-met,expressing PTC cells was determined, and growth curves at 0.1×, 1×, and 10× IC50 concentrations were obtained. Poly(ADP-ribose) polymerase (PARP) and caspase-9-processing post-PHA665752 treatment were studied as markers of apoptosis, and assays analyzing HGF-dependent cell invasion and migration in the presence and absence of PHA665752 were done. Results c-Met was upregulated in most of the patient tissues with PTC and in many PTC cell lines. PHA665752 specifically inhibited c-met phosphorylation, c-met,dependent cell growth, signal transduction, cell survival, cell invasion, and migration in PTC cells with high c-met. Conclusions PHA665752 is an effective and specific inhibitor of c-met in PTC cells with high levels of c-met expression. © 2008 Wiley Periodicals, Inc. Head Neck, 2008 [source] Epithelial-to-mesenchymal transition of murine liver tumor cells promotes invasion,,HEPATOLOGY, Issue 3 2010Wei Ding Epithelial-to-mesenchymal transition (EMT) is predicted to play a critical role in metastatic disease in hepatocellular carcinoma. In this study, we used a novel murine model of EMT to elucidate a mechanism of tumor progression and metastasis. A total of 2 × 106 liver cells isolated from Ptenloxp/loxp/Alb-Cre+ mice, expanded from a single CD133+CD45, cell clone, passage 0 (P0), were sequentially transplanted to obtain two passages of tumor cells, P1 and P2. Cells were analyzed for gene expression using microarray and real-time polymerase chain reaction. Functional analysis included cell proliferation, migration, and invasion in vitro and orthotopic tumor metastasis assays in vivo. Although P0, P1, and P2 each formed tumors consistent with mixed liver epithelium, within the P2 cells, two distinct cell types were clearly visible: cells with epithelial morphology similar to P0 cells and cells with fibroblastoid morphology. These P2 mesenchymal cells demonstrated increased locomotion on wound healing; increased cell invasion on Matrigel basement membrane; increased EMT-associated gene expression of Snail1, Zeb1, and Zeb2; and down-regulated E-cadherin. P2 mesenchymal cells demonstrated significantly faster tumor growth in vivo compared with P2 epithelial counterparts, with invasion of intestine, pancreas, spleen, and lymph nodes. Furthermore, P2 mesenchymal cells secreted high levels of hepatocyte growth factor (HGF), which we propose acts in a paracrine fashion to drive epithelial cells to undergo EMT. In addition, a second murine liver cancer stem cell line with methionine adenosyltransferase 1a deficiency acquired EMT after sequential transplantations, indicating that EMT was not restricted to Pten-deleted tumors. Conclusion: EMT is associated with a high rate of liver tumor proliferation, invasion, and metastasis in vivo, which is driven by HGF secreted from mesenchymal tumor cells in a feed-forward mechanism. (HEPATOLOGY 2010) [source] Inhibition of poly adenosine diphosphate-ribose polymerase decreases hepatocellular carcinoma growth by modulation of tumor-related gene expression,HEPATOLOGY, Issue 1 2010Rosa Quiles-Perez Hepatocellular carcinoma (HCC) is associated with a poor prognosis due to a lack of effective treatment options. In HCC a significant role is played by DNA damage and the inflammatory response. Poly (ADP-ribose) polymerase-1 (PARP-1) is an important protein that regulates both these mechanisms. The objective of this study was to examine the effect of pharmacology PARP-1 inhibition on the reduction of tumor volume of HCC xenograft and on the hepatocarcinogenesis induced by diethyl-nitrosamine (DEN). Pharmacologic PARP-1 inhibition with DPQ greatly reduces tumor xenograft volume with regard to a nontreated xenograft (394 mm3 versus 2,942 mm3, P < 0.05). This observation was paralleled by reductions in xenograft mitosis (P = 0.02) and tumor vasculogenesis (P = 0.007, confirmed by in vitro angiogenesis study), as well as by an increase in the number of apoptotic cells in DPQ-treated mice (P = 0.04). A substantial difference in key tumor-related gene expression (transformed 3T3 cell double minute 2 [MDM2], FLT1 [vascular endothelial growth factor receptor-1, VEGFR1], epidermal growth factor receptor [EPAS1]/hypoxia-inducible factor 2 [HIF2A], EGLN1 [PHD2], epidermal growth factor receptor [EGFR], MYC, JUND, SPP1 [OPN], hepatocyte growth factor [HGF]) was found between the control tumor xenografts and the PARP inhibitor-treated xenografts (data confirmed in HCC cell lines using PARP inhibitors and PARP-1 small interfering RNA [siRNA]). Furthermore, the results obtained in mice treated with DEN to induce hepatocarcinogenesis showed, after treatment with a PARP inhibitor (DPQ), a significant reduction both in preneoplastic foci and in the expression of preneoplastic markers and proinflammatory genes (Gstm3, Vegf, Spp1 [Opn], IL6, IL1b, and Tnf), bromodeoxyuridine incorporation, and NF-,B activation in the initial steps of carcinogenesis (P < 0.05). Conclusion: This study shows that PARP inhibition is capable of controlling HCC growth and preventing tumor vasculogenesis by regulating the activation of different genes involved in tumor progression. (HEPATOLOGY 2010;51:255,266.) [source] Cell cycle effects resulting from inhibition of hepatocyte growth factor and its receptor c-Met in regenerating rat livers by RNA interference,HEPATOLOGY, Issue 6 2007Shirish Paranjpe Hepatocyte growth factor (HGF) and its receptor c-Met are involved in liver regeneration. The role of HGF and c-Met in liver regeneration in rat following two-thirds partial hepatectomy (PHx) was investigated using RNA interference to silence HGF and c-Met in separate experiments. A mixture of 2 c-Met-specific short hairpin RNA (ShRNA) sequences, ShM1 and ShM2, and 3 HGF-specific ShRNA, ShH1, ShH3, and ShH4, were complexed with linear polyethylenimine. Rats were injected with the ShRNA/PEI complex 24 hours before and at the time of PHx. A mismatch and a scrambled ShRNA served as negative controls. ShRNA treatment resulted in suppression of c-Met and HGF mRNA and protein compared with that in controls. The regenerative response was assessed by PCNA, mitotic index, and BrdU labeling. Treatment with the ShHGF mixture resulted in moderate suppression of hepatocyte proliferation. Immunohistochemical analysis revealed severe suppression of incorporation of BrdU and complete absence of mitosis in rats treated with ShMet 24 hours after PHx compared with that in controls. Gene array analyses indicated abnormal expression patterns in many cell-cycle- and apoptosis-related genes. The active form of caspase 3 was seen to increase in ShMet-treated rats. The TUNEL assay indicated a slight increase in apoptosis in ShMet-treated rats compared with that in controls. Conclusion: The data indicated that in vivo silencing of c-Met and HGF mRNA by RNA interference in normal rats results in suppression of mRNA and protein, which had a measurable effect on proliferation kinetics associated with liver regeneration. (HEPATOLOGY 2007.) [source] p53 may positively regulate hepatocyte proliferation in ratsHEPATOLOGY, Issue 2 2002Yukiko Inoue p53, known as a tumor suppressor gene, is a transcription factor that regulates various cellular functions. Recently, several growth factor gene promoters, including that of transforming growth factor , (TGF-,), were shown to be direct targets of p53-mediated transcription. Hepatic p53 mRNA is up-regulated during liver regeneration in rats. The aim of this study is to examine the role of p53 in hepatocyte proliferation. p53 protein levels were examined in rat hepatocytes cultured in the medium containing hepatocyte growth factor (HGF). p53 levels began to increase after 6 hours of incubation, reached a maximum at 18 hours, and decreased thereafter. DNA synthesis increased at 12 hours and peaked at 30 hours. When hepatocytes were incubated with p53 antisense oligonucleotide in addition to HGF, increases of p53 and TGF-, levels were suppressed, and DNA synthesis was reduced. The increases of TGF-, levels and DNA synthesis were also suppressed by a chemical inhibitor of p53, pifithrin-,. In rats after two-thirds partial hepatectomy, hepatic p53 increased and reached maximal levels around 16 hours when hepatic HGF levels have been shown to reach a maximum followed by an increase in hepatic TGF-, levels or hepatocyte proliferation. In contrast, sham-operated rats showed minor elevations of hepatic p53 levels. In conclusion, p53 production is stimulated by HGF and may contribute to the proliferation of rat hepatocytes. Considering previous findings indicating the importance of endogenous TGF-, for the proliferation of hepatocytes stimulated by HGF, TGF-, might play a role in HGF-p53 mediated hepatocyte proliferation. [source] Liver cell proliferation requires methionine adenosyltransferase 2A mRNA up-regulationHEPATOLOGY, Issue 6 2002Covadonga Pañeda Regulation of liver cell proliferation is a key event to control organ size during development and liver regeneration. Methionine adenosyltransferase (MAT) 2A is expressed in proliferating liver, whereas MAT1A is the form expressed in adult quiescent hepatocytes. Here we show that, in H35 hepatoma cells, growth factors such as hepatocyte growth factor (HGF) and insulin up-regulated MAT2A expression. HGF actions were time- and dose-response dependent and required transcriptional activity. Mitogen-activated protein (MAP) kinase and phosphatidylinositol 3-phosphate kinase (PI 3-K) pathways were required for both HGF-induced cell proliferation and MAT2A up-regulation. Furthermore, in H35 cells treated with HGF, the inhibition of these pathways was associated with the switch from the expression of fetal liver MAT2A to the adult liver MAT1A isoform. Fetal liver hepatocytes exhibited an identical response pattern. Treatment of H35 hepatoma cells with MAT2A antisense oligonucleotides decreased cell proliferation induced by HGF; this decrease correlated with the decay in MAT2A messenger RNA (mRNA) levels. Finally, growth inhibitors such as transforming growth factor (TGF) , blocked HGF-induced MAT2A up-regulation while increasing MAT1A mRNA levels in H35 cells. In conclusion, our results show that MAT2A expression not only correlates with liver cell proliferation but is required for this process. [source] Hepatocyte growth factor promotes cell survival from Fas-mediated cell death in hepatocellular carcinoma cells via Akt activation and Fas-death,inducing signaling complex suppressionHEPATOLOGY, Issue 4 2000Atsushi Suzuki The Akt/PI-3 kinase pathway is a system essential for cell survival. In the current study, we showed that hepatocyte growth factor (HGF) activates the Akt/PI-3 kinase pathway to suppress Fas-mediated cell death in human hepatocellular carcinoma (HCC; 3 lines; SK-Hep1, HLE, and Chang Liver cell lines), hepatoblastoma (1 line; HepG2), and embryonic hepatocyte (1 line; WRL). Five tested cell lines showed the resistance to Fas-mediated cell death by the pretreatment of HGF. This HGF-induced cell survival was suppressed by wortmannin (Akt/PI-3 kinase pathway inhibitor), suggesting an involvement of Akt. When cells were pretreated with HGF, Fas-mediated cell death was suppressed, followed by Akt phosphorylation at Ser473. Fas-death,inducing signaling complex (DISC) formation, especially FADD and caspase 8 interaction, was suppressed by HGF and the suppression of the Akt/PI-3 kinase pathway by transient expression of PTEN, resulting in acquisition of Fas-DISC formation and Fas-mediated cell death in HGF-treated cells. We suggest that HGF promotes cell survival in hepatocyte-derived cell lines (HCC, hepatoblastoma, and embryonic hepatocyte) from Fas-mediated cell death via Fas-DISC suppression as a result of Akt activation. [source] Serum HGF and TGF-,1 levels after right portal vein embolizationHEPATOLOGY RESEARCH, Issue 3 2010Hiromitsu Hayashi Aim:, The changes in the serum hepatocyte growth factor (HGF) and transforming growth factor (TGF)-beta1 levels after portal vein embolization (PVE), and their clinical significance, remain unclear and we aimed to assess their relationship. Methods:, The serum HGF and TGF-beta1 levels were prospectively measured in 22 patients before and 1, 3, 5, 7, and 14 day after right PVE. Computed tomographic volumetry was performed before and at a mean of 26 ± 4 days after right PVE. Results:, Three to four weeks after right PVE, the volume of embolized lobe significantly decreased from 704 ± 157 cm3 before PVE to 539 ± 168 cm3 after PVE (P < 0.001). In contrast, the volume of nonembolized lobe significantly increased from 426 ± 142 cm3 to 560 ± 165 cm3 (P < 0.001). The serum HGF level significantly increased on day 3 after PVE compared with the pretreatment level (P = 0.005), while the serum TGF-beta1 level significantly decreased and reached its lowest value on day 3 (P = 0.002). Using Pearson's correlation analysis, we found that the serum HGF and TGF-beta1 levels on day 14 negatively associated with the large hypertrophic response in the nonembolized lobe (HGF: r = ,0.490, P = 0.021; TGF-beta1: r = ,0.473, P = 0.026). Conclusions:, PVE induced an increase in the serum HGF level and reduced the serum TGF-beta1 level. Measurement of serum HGF and TGF-beta1 levels on day 14 after right PVE may be useful for assessment of the future liver hypertrophy in nonembolized lobe after right PVE. [source] Lipoxin A4 inhibited hepatocyte growth factor-induced invasion of human hepatoma cellsHEPATOLOGY RESEARCH, Issue 9 2009Xiao-Yan Zhou Aim:, Inflammation is a critical component of tumor progression. Lipoxin A4 (LXA4) has been approved for potent anti-inflammatory properties. Recently, it was reported that LXA4 repressed the expression and activity of cyclooxygenase-2 (COX-2), which is essential for invasion. However, there are few reports dealing with its effects on cancer. To explore whether LXA4 regulate invasion, the effects of LXA4 and its receptor agonist BML-111 on hepatocyte growth factor (HGF)-induced invasion of hepatoma cells and the possible mechanisms were researched. Methods:, Lipoxin A4 receptor (ALX) expression in HepG2 cells were measured through reverse transcription polymerase chain reaction and western blot. Cytotoxicity of LXA4 and BML-111 to HepG2 cells was detected by MTT and (3H)-TdR incorporation assay. Cell migration and invasion assays were performed using a Boyden chemotaxis chamber. COX-2 expression was detected by real-time polymerase chain reaction and western blot, respectively. Moreover, the expressions of matrix metalloproteinases (MMP)-2, MMP-9, I,B, and nuclear factor-,B (NF-,B) p65 were observed via western blot, and NF-,B transcriptional activity was tested by transfections and luciferase activities assay. Results:, ALX expression was detected in HepG2 cells, and suitable concentrations of LXA4 and BML-111 had no cytotoxicity to cells. LXA4 and BML-111 inhibited HGF-induced migration and invasion; downregulated COX-2, MMP-2 and -9; restrained HGF-induced I,B, degradation, NF-,B translocation and the transcriptional activity of NF-,B in HepG2 cells. Furthermore, exogenous PGE2 could reverse the inhibitory effects of LXA4 also BML-111 on HGF-induced invasion and migration partially. Conclusion:, LXA4 inhibited HGF-induced invasion of HepG2 cells through NF-,B/COX-2 signaling pathway partially. [source] Translational research to identify clinical applications of hepatocyte growth factorHEPATOLOGY RESEARCH, Issue 8 2009Akio Ido Hepatocyte growth factor (HGF), originally purified from the plasma of patients with fulminant hepatic failure, has been shown to carry out various physiological functions. HGF not only stimulates liver regeneration, but also acts as an antiapoptotic factor in in vivo experimental models. Therefore, HGF is a promising therapeutic agent for the treatment of fatal liver diseases, including fulminant hepatic failure. After performing a number of preclinical tests, our group began an investigator-initiated registered phase I/II clinical trial of patients with fulminant hepatic failure to examine the safety and clinical efficacy of recombinant human HGF. In this article, we will discuss the basic research results as well as the translational research that underpins current attempts to use HGF in various clinical settings. [source] Hepatic differentiation of human bone marrow-derived UE7T-13 cells: Effects of cytokines and CCN family gene expressionHEPATOLOGY RESEARCH, Issue 12 2007Takashi Shimomura Aim:, Bone marrow-derived mesenchymal stem cells (MSC) are expected to be an excellent source of cells for transplantation. We aimed to study the culture conditions and involved genes to differentiate MSC into hepatocytes. Methods:, The culture conditions to induce the efficient differentiation of human bone marrow-derived UE7T-13 cells were examined using cytokines, hormones, 5-azacytidine and type IV collagen. Results:, We found that combination of acidic fibroblast growth factor (aFGF), basic fibroblast growth factor (bFGF) and hepatocyte growth factor (HGF) with type IV collagen coating induced hepatic differentiation of UE7T-13 cells at over 30% frequency, where expression of albumin mRNA was increased over 20-fold. The differentiated cells had functions of albumin production, glycogen synthesis and urea secretion as well as expressing hepatocyte-specific genes. In addition, these cellshave binuclear and cuboidal morphology, which is a characteristic feature of hepatocytes. During hepatic differentiation, UE7T-13 cells showed depressed expression of WISP1 and WISP2 genes, members of the CCN family. Conversely, knockdown of WISP1 or WISP2 gene by siRNA stimulated hepatic differentiation. The effect of aFGF/bFGF/HGF/type IV collagen coating and WISP1-siRNA on hepatic differentiation was additive. Conclusion:, The present study suggests that aFGF/bFGF/HGF/type IV collagen coating is the efficient condition for hepatic differentiation of UE7T-13 cells, and that WISP1 and WISP2 play an important role in hepatic transdifferentiation of these cells. [source] Expression of c-MET, low-molecular-weight cytokeratin, matrix metalloproteinases-1 and -2 in spinal chordomaHISTOPATHOLOGY, Issue 5 2009Takahiko Naka Aims:, In skull base chordoma, c-MET expression has been reported to correlate with younger patient age and favourable prognosis; however, it also contributes to tumour invasiveness, especially in recurrent lesions, suggesting variable roles for c-MET according to clinical status. The aim of this study was to investigate the significance of c-MET expression in spinal chordoma, which affects patients who are 10,20 years older than those with skull base chordoma. Methods and results:, Using immunohistochemical techniques, the expression of c-MET and its ligand, hepatocyte growth factor (HGF) was investigated in 34 primary spinal chordomas and compared with other clinicopathological parameters. Expression of c-MET and HGF was observed in 85.3 and 21.7% of lesions, respectively. c-MET expression correlated with the expression of an epithelial marker, low-molecular-weight cytokeratin (CAM5.2). Lesions with higher c-MET expression showed significantly stronger expression of proteinases, including matrix metalloproteinase (MMP)-1 and MMP-2. However, c-MET expression was not associated with patient age, proliferative ability estimated by MIB-1 labelling index, or prognosis. Conclusions:, c-MET expression was observed in most spinal chordomas and correlated with the expression of CAM5.2, suggesting a relationship to an epithelial phenotype. [source] Growth factor attenuation of IFN,-mediated hepatocyte apoptosis requires p21waf,1INTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 4 2006Christian T. McCullough Summary Interferon gamma (IFN,) is an important mediator of inflammatory liver damage as part of a complex cytokine network. In vitro, IFN, induces hepatocyte apoptosis. We hypothesized that the hepatocyte response to IFN signalling is context-dependent, and that specific growth factors, via phosphatidylinositol 3 kinase (PI(3)K) and protein kinase B/Akt signalling pathways, confer a cytoprotective effect. We established an in vitro model of IFN,-mediated primary hepatocyte injury. We show that epidermal growth factor (EGF) and hepatocyte growth factor (HGF) attenuate the IFN,-induced hepatocyte apoptosis. IRF-1, but not p53, is required for IFN,-mediated apoptosis. The loss of p21waf,1 not only sensitizes the hepatocyte to IFN,-mediated injury but is required for survival factor mediated cytoprotection. We show that the PI(3)K inhibitor, LY294002, partially inhibits the apoptotic response of the hepatocyte to IFN,. In summary, we present evidence that a component of pro-apoptotic IFN, signalling in the primary hepatocyte occurs via the PI(3)K pathway. We show that the hepatocyte response to IFN, is modulated by external survival factors and that this survival signalling requires p21waf,1. [source] Hepatocyte Growth Factor Contributes to Fracture Repair by Upregulating the Expression of BMP Receptors,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 10 2005Yuuki Imai MD Abstract Hepatocyte growth factor (HGF) is activated and the expression of BMP receptors (BMPRs) is induced around the fracture site during the early phase of fracture repair. HGF facilitates the expression of BMPRs in mesenchymal cells. This study suggests that HGF contributes to fracture repair by inducing the expression of BMPRs. Introduction: The precise mechanisms that control the upregulation of BMP, BMPRs, and other molecules involved in bone repair are not completely understood. In this study, we hypothesized that HGF, activated through the action of thrombin on the HGF activator, may enhance BMP action through the local induction of BMP or BMPRs. Materials and Methods: Callus samples from tibial fractures in mice were harvested for immunohistochemical analysis of HGF and phosphorylated c-Met, for in situ hybridization of BMPRs, and for real-time RT-PCR analysis for the expression of HGF, c-Met, and BMPRs. To study the changes in gene expression of BMPRs in response to HGF, C3H10T1/2 cells were cultured with or without HGF and harvested for real-time RT-PCR and for Western blot analysis. To evaluate the contribution of HGF to the biological action of BMP2, C3H10T1/2 cells and primary muscle-derived mesenchymal cells were precultured with HGF and cultured with BMP2. In addition, the expression of the luciferase gene linked to the Id1 promoter containing the BMP responsive element and alkaline phosphatase (ALP) activity were assayed. Results: Positive immunostaining of HGF and phosphorylated c-Met was detected around the fracture site at 1 day after the fracture was made. mRNA expression of BMPRs was increased 1 day after fracture and localized in mesenchymal cells at the fracture site. From an in vitro study, the expression of mRNA for BMPRs was elevated by treatment with HGF, but the expression of BMP4 did not change. Western blot analysis also showed the upregulation of BMPR2 by HGF treatment. The results from the luciferase and ALP assays indicated increased responsiveness to BMPs by treating with HGF. Conclusions: This study indicates that HGF is activated and expressed at the fracture site and that HGF induces the upregulation of BMPRs in mesenchymal cells. Furthermore, HGF may facilitate BMP signaling without altering the expression of BMP molecules. [source] Induction of Angiogenesis and Inhibition of Apoptosis by Hepatocyte Growth Factor Effectively Treats Postischemic Heart FailureJOURNAL OF CARDIAC SURGERY, Issue 1 2005Vasant Jayasankar M.D. Hepatocyte growth factor (HGF) is a potent angiogenic and anti-apoptotic protein whose receptor is upregulated following MI. This study was designed to investigate the ability of HGF to prevent heart failure in a rat model of experimental MI. Methods: The rats underwent direct intramyocardial injection with replication-deficient adenovirus encoding HGF (n = 7) or null virus as control (n = 7) 3 weeks following ligation of the left anterior descending coronary artery. Analysis of the following was performed 3 weeks after injection: cardiac function by pressure,volume conductance catheter measurements; LV wall thickness; angiogenesis by Von Willebrand's factor staining; and apoptosis by the TUNEL assay. The expression levels of HGF and the anti-apoptotic factor Bcl-2 were analyzed by Western blot. Results: Adeno-HGF-treated animals had greater preservation of maximum LV pressure (HGF 77 ± 3 vs. control 64 ± 5 mmHg, p < 0.05), maximum dP/dt (3024 ± 266 vs. 1907 ± 360 mmHg/sec, p < 0.05), maximum dV/dt (133 ± 20 vs. 84 ± 6 ,L/sec, p < 0.05), and LV border zone wall thickness (1.98 ± 0.06 vs. 1.53 ± 0.07 mm, p < 0.005). Angiogenesis was enhanced (151 ± 10.0 vs. 90 ± 4.5 endothelial cells/hpf, p < 0.005) and apoptosis was reduced (3.9 ± 0.3 vs. 8.2 ± 0.5%, p < 0.005). Increased expression of HGF and Bcl-2 protein was observed in the Adeno-HGF-treated group. Conclusions: Overexpression of HGF 3 weeks post-MI resulted in enhanced angiogenesis, reduced apoptosis, greater preservation of ventricular geometry, and preservation of cardiac contractile function. This technique may be useful to treat or prevent postinfarction heart failure. [source] Induction of hepatic differentiation of mouse bone marrow stromal stem cells by the histone deacetylase inhibitor VPAJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 8b 2009Ye Chen Abstract Bone marrow stromal stem cells (BMSSCs) may have potential to differentiate in vitro and in vivo into hepatocytes. Here, we investigated the effects of valproic acid (VPA) involved in epigenetic modification, a direct inhibitor of histone deacetylase, on hepatic differentiation of mouse BMSSCs. Following the treatment of 2.5 mM VPA for 72 hrs, the in vitro expanded, highly purified and functionally active mouse BMSSCs from bone marrow were either exposed to some well-defined cytokines and growth factors in a sequential way (fibroblast growth factor-4 [FGF-4], followed by HGF, and HGF + OSM + ITS + dexamethasone, resembling the order of secretion during liver embryogenesis) or transplanted (caudal vein) in mice submitted to a protocol of chronic injury (chronic i.p. injection of CCl4). Additional exposure of the cells to VPA considerably improved the in vitro differentiation, as demonstrated by a more homogeneous cell population exhibited epithelial morphology, increasing expression of hepatic special genes and enhanced hepatic functions. Further more, in vivo results indicate that the pre-treatment of VPA significantly increased the homing efficiency of BMSSCs to the site of liver injury and, additionally, for supporting hepatic differentiation as well as in vitro. We have demonstrated the usefulness of VPA in the transdifferentiation of BMSSCs into hepatocytes both in vitro and in vivo, and regulation of fibroblast growth factor receptors (FGFRs) and c-Met gene expression through post-translational modification of core histones might be the primary initiating event for these effects. This mode could be helpful for liver engineering and clinical therapy. [source] Src and FAK mediate cell,matrix adhesion-dependent activation of met during transformation of breast epithelial cellsJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 6 2009Angela Y. Hui Abstract Cell,matrix adhesion has been shown to promote activation of the hepatocyte growth factor receptor, Met, in a ligand-independent manner. This process has been linked to transformation and tumorigenesis in a variety of cancer types. In the present report, we describe a key role of integrin signaling via the Src/FAK axis in the activation of Met in breast epithelial and carcinoma cells. Expression of an activated Src mutant in non-neoplastic breast epithelial cells or in carcinoma cells was found to increase phosphorylation of Met at regulatory tyrosines in the auto-activation loop domain, correlating with increased cell spreading and filopodia extensions. Furthermore, phosphorylated Met is complexed with ,1 integrins and is co-localized with vinculin and FAK at focal adhesions in epithelial cells expressing activated Src. Conversely, genetic or pharmacological inhibition of Src abrogates constitutive Met phosphorylation in carcinoma cells or epithelial cells expressing activated Src, and inhibits filopodia formation. Interestingly, Src-dependent phosphorylation of Met requires cell,matrix adhesion, as well as actin stress fiber assembly. Phosphorylation of FAK by Src is also required for Src-induced Met phosphorylation, emphasizing the importance of the Src/FAK signaling pathway. However, stimulation of Met phosphorylation by addition of exogenous HGF in epithelial cells is refractory to inhibition of Src family kinases, indicating that HGF-dependent and Src/integrin-dependent Met activation occur via distinct mechanisms. Together these findings demonstrate a novel mechanism by which the Src/FAK axis links signals from the integrin adhesion complex to promote Met activation in breast epithelial cells. J. Cell. Biochem. 107: 1168,1181, 2009. © 2009 Wiley-Liss, Inc. [source] Dermatan sulfate exerts an enhanced growth factor response on skeletal muscle satellite cell proliferation and migrationJOURNAL OF CELLULAR PHYSIOLOGY, Issue 2 2004Joan Villena Skeletal muscle regeneration is a complex process in which many agents are involved. When skeletal muscle suffers an injury, quiescent resident myoblasts called satellite cells are activated to proliferate, migrate, and finally differentiate. This whole process occurs in the presence of growth factors, the extracellular matrix (ECM), and infiltrating macrophages. We have shown previously that different proteoglycans, either present at the plasma membrane or the ECM, are involved in the differentiation process by regulating growth factor activity. In this article, we evaluated the role of glycosaminoglycans (GAGs) in myoblast proliferation and migration, using C2C12, a satellite cell-derived cell line. A synergic stimulatory effect on myoblast proliferation was observed with hepatocyte growth factor (HGF) and fibroblast growth factor type 2 (FGF-2), which was dependent on cell sulfation. The GAG dermatan sulfate (DS) enhanced HGF/FGF-2-dependent proliferation at 1,10 ng/ml. However, decorin, a proteoglycan containing DS, was unable to reproduce this enhanced proliferative effect. On the other hand, HGF strongly increased myoblast migration. The HGF-dependent migratory process required the presence of sulfated proteoglycans/GAGs present on the myoblast surface, as inhibition of both cell sulfation, and heparitinase (Hase) and chondroitinase ABC (Chabc) treatment of myoblasts, resulted in a very strong inhibition of cell migration. Among the GAGs analyzed, DS most increased HGF-dependent myoblast migration. Taken together, these findings showed that DS is an enhancer of growth factor-dependent proliferation and migration, two critical processes involved in skeletal muscle formation. J. Cell. Physiol. 198: 169,178, 2004© 2003 Wiley-Liss, Inc. [source] Further evidence of genetic heterogeneity segregating with hereditary gingival fibromatosisJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 8 2009Xiaoqian Ye Abstract Aim: To clinically characterize and map the disease-associated locus in a five-generation Chinese family with autosomal dominant early-onset hereditary gingival fibromatosis (HGF). Material and Methods: A complete oral examination was conducted. Genomic DNA samples were obtained from 14 individuals. Short tandem repeats markers, which encompass four previously known loci related to HGF, were genotyped. Two-point log of the odds (LOD) scores were calculated using MLINK program of the LINKAGE software, multipoint and non-parametric linkage (NPL) analysis were performed using the GENEHUNTER software. Results: Clinical evaluation and histological examination of this family suggested typical features of HGF. The onset age was early in the generations, ranging between 1 and 2 years. None of the tested markers showed cosegregation among affected individuals. Genotyping data from four putative regions yielded significant negative two-point LOD scores (<,2.0) at ,=0. The maximum multipoint LOD scores and NPL analysis revealed exclusion of these loci as well. Conclusions: Exclusion of linkage in this family to any of the known HGF loci proved the existence of a novel locus for autosomal dominant HGF and showed that this rare disorder is far more heterogeneous than previously expected. [source] Transforming growth factor- , stimulates Interleukin-11 production by human periodontal ligament and gingival fibroblastsJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 3 2006R. Yashiro Abstract Background: Transforming growth factor (TGF)- , is a potent multifunctional polypeptide, abundant in the bone matrix. Interleukin (IL)-11 is a pleiotropic cytokine with effects on multiple cell types. The present study was performed to evaluate the regulatory effects of TGF- , on IL-11 production by human periodontal ligament cells (PDL) and human gingival fibroblasts (HGF). Material and Methods: The expression of TGF- , receptor in PDL and HGF were observed using flow cytometry. PDL and HGF were stimulated with TGF- , with or without protein kinase C (PKC) inhibitors and activator. IL-11, bone morphogenetic protein-2 (BMP-2) and TGF- , mRNA expression was quantified by real-time polymerase chain reaction (PCR). IL-11 production was measured using enzyme-linked immunosorbent assay. Results: PDL and HGF expressed both TGF- , receptor I and TGF- , receptor II on the cell surfaces. IL-11 mRNA expression and IL-11 production were augmented by TGF- , in both PDL and HGF, with higher values in PDL. PKC inhibitors partially suppressed TGF- , -induced IL-11 production in PDL and HGF, whereas activator enhanced it. TGF- , mRNA and BMP-2 mRNA expression were up-regulated by TGF- , in PDL. Conclusion: These results suggest that PDL produce IL-11 in response to TGF- ,. [source] Predominant formation of heavily pigmented dermal melanocytomas resembling ,animal-type' melanomas in hepatocyte growth factor (C57BL/6 × C3H)F1 mice following neonatal UV irradiationJOURNAL OF CUTANEOUS PATHOLOGY, Issue 9 2007Scott R. Florell Background:, Transgenic mice expressing hepatocyte growth factor (HGF) develop cutaneous melanocytic tumors following neonatal UV exposure. Here, we examined the histologic spectrum of UV-induced melanocytic tumors in HGF mice on a pigmented (C57BL/6 × C3H/HeN)F1 background. Methods:, Neonatally irradiated (4000 J/m2) mice were monitored for 43 weeks, and 31/34 (91%) animals developed a total of 163 melanocytic tumors. Results:, Of 54 primary tumors analyzed, most (49/54, 91%) demonstrated exclusively dermal collections of epithelioid cells with voluminous densely pigmented cytoplasm. Seven of these also demonstrated a population of spindled cells with mitoses. Several (3/54, 6%) tumors exhibited a junctional component with melanocytes present in the epidermis. Staining with PEP8 confirmed the presence of interfollicular melanocytes at the dermal-epidermal junction in neonatal skin. Conclusions:, In contrast to HGF animals on an albino (FVB) background, HGF animals on the pigmented (C57BL/6 × C3H/HeN)F1 background do not develop classic radial growth phase melanoma but rather predominantly develop dermal melanocytomas resembling the ,animal-type' melanoma occasionally seen in humans. These results demonstrate the influence of genetic background on histologic pattern of UV-induced melanomas in mice. [source] | |||||||||||||||||||||||||||||||||||||