Regulation of insulin-like growth factor I receptors on vascular smooth muscle cells by growth factors and phorbol esters.

PubMed

Ververis, J J; Ku, L; Delafontaine, P

1993-06-01

Insulin-like growth factor I (IGF I) is an important mitogen for vascular smooth muscle cells. To characterize regulation of vascular IGF I receptors, we performed radioligand displacement experiments using rat aortic smooth muscle cells (RASMs). Serum deprivation for 48 hours caused a 40% decrease in IGF I receptor number. Exposure of quiescent RASMs to platelet-derived growth factor (PDGF), fibroblast growth factor (FGF), or angiotensin II (Ang II) caused a 1.5-2.0-fold increase in IGF I receptors per cell. After FGF exposure, there was a marked increase in the mitogenic response to IGF I. IGF I downregulated its receptors in the presence of platelet-poor plasma. Stimulation of protein kinase C (PKC) by exposure of quiescent RASMs to phorbol 12-myristate 13-acetate caused a biphasic response in IGF I binding; there was a 42% decrease in receptor number at 45 minutes and a 238% increase at 24 hours. To determine the role of PKC in growth factor-induced regulation of IGF I receptors, we downregulated PKC by exposing RASMs to phorbol 12,13-dibutyrate (PDBu) for 48 hours. PDGF- and FGF- but not Ang II-mediated upregulation of IGF I receptors was completely inhibited in PDBu-treated cells. Thus, acute PKC activation by phorbol esters inhibits IGF I binding, whereas chronic PKC activation increases IGF I binding. PDGF and FGF but not Ang II regulate vascular IGF I receptors through a PKC-dependent pathway. These data provide new insights into the regulation of vascular smooth muscle cell IGF I receptors in vitro and are of potential importance in characterizing vascular proliferative responses in vivo.

Activation of Stat1 by mutant fibroblast growth-factor receptor in thanatophoric dysplasia type II dwarfism.

PubMed

Su, W C; Kitagawa, M; Xue, N; Xie, B; Garofalo, S; Cho, J; Deng, C; Horton, W A; Fu, X Y

1997-03-20

The achondroplasia class of chondrodysplasias comprises the most common genetic forms of dwarfism in humans and includes achondroplasia, hypochondroplasia and thanatophoric dysplasia types I and II (TDI and TDII), which are caused by different mutations in a fibroblast growth-factor receptor FGFR3 (ref. 1). The molecular mechanism and the mediators of these FGFR3-related growth abnormalities are not known. Here we show that mutant TDII FGFR3 has a constitutive tyrosine kinase activity which can specifically activate the transcription factor Stat1 (for signal transducer and activator of transcription). Furthermore, expression of TDII FGFR3 induced nuclear translocation of Stat1, expression of the cell-cycle inhibitor p21(WAF1/CIP1), and growth arrest of the cell. Thus, TDII FGFR3 may use Stat1 as a mediator of growth retardation in bone development. Consistent with this, Stat1 activation and increased p21(WAF1/CIP1) expression was found in the cartilage cells from the TDII fetus, but not in those from the normal fetus. Thus, abnormal STAT activation and p21(WAF1/CIP1) expression by the TDII mutant receptor may be responsible for this FGFR3-related bone disease.

Insulin-Like growth factor-II (IGF-II) prevents proinflammatory cytokine-induced apoptosis and significantly improves islet survival after transplantation.

PubMed

Hughes, Amy; Mohanasundaram, Daisy; Kireta, Svjetlana; Jessup, Claire F; Drogemuller, Chris J; Coates, P Toby H

2013-03-15

The early loss of functional islet mass (50-70%) due to apoptosis after clinical transplantation contributes to islet allograft failure. Insulin-like growth factor (IGF)-II is an antiapoptotic protein that is highly expressed in β-cells during development but rapidly decreases in postnatal life. We used an adenoviral (Ad) vector to overexpress IGF-II in isolated rat islets and investigated its antiapoptotic action against exogenous cytokines interleukin-1β- and interferon-γ-induced islet cell death in vitro. Using an immunocompromised marginal mass islet transplant model, the ability of Ad-IGF-II-transduced rat islets to restore euglycemia in nonobese diabetic/severe combined immunodeficient diabetic recipients was assessed. Ad-IGF-II transduction did not affect islet viability or function. Ad-IGF-II cytokine-treated islets exhibited decreased cell death (40% ± 2.8%) versus Ad-GFP and untransduced control islets (63.2% ± 2.5% and 53.6% ± 2.3%, respectively). Ad-IGF-II overexpression during cytokine treatment resulted in a marked reduction in terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling-positive apoptotic cells (8.3% ± 1.4%) versus Ad-GFP control (41% ± 4.2%) and untransduced control islets (46.5% ± 6.2%). Western blot analysis confirmed that IGF-II inhibits apoptosis via activation of the phosphatidylinositol 3-kinase/Akt signaling pathway. Transplantation of IGF-II overexpressing islets under the kidney capsule of diabetic mice restored euglycemia in 77.8% of recipients compared with 18.2% and 47.5% of Ad-GFP and untransduced control islet recipients, respectively (P<0.05, log-rank [Mantel-Cox] test). Antiapoptotic IGF-II decreases apoptosis in vitro and significantly improved islet transplant outcomes in vivo. Antiapoptotic gene transfer is a potentially powerful tool to improve islet survival after transplantation.

Insulin-like growth factor-I and growth differentiation factor-5 promote the formation of tissue-engineered human nasal septal cartilage.

PubMed

Alexander, Thomas H; Sage, August B; Chen, Albert C; Schumacher, Barbara L; Shelton, Elliot; Masuda, Koichi; Sah, Robert L; Watson, Deborah

2010-10-01

Tissue engineering of human nasal septal chondrocytes offers the potential to create large quantities of autologous material for use in reconstructive surgery of the head and neck. Culture with recombinant human growth factors may improve the biochemical and biomechanical properties of engineered tissue. The objectives of this study were to (1) perform a high-throughput screen to assess multiple combinations of growth factors and (2) perform more detailed testing of candidates identified in part I. In part I, human nasal septal chondrocytes from three donors were expanded in monolayer with pooled human serum (HS). Cells were then embedded in alginate beads for 2 weeks of culture in medium supplemented with 2% or 10% HS and 1 of 90 different growth factor combinations. Combinations of insulin-like growth factor-I (IGF-1), bone morphogenetic protein (BMP)-2, BMP-7, BMP-13, growth differentiation factor-5 (GDF-5), transforming growth factor β (TGFβ)-2, insulin, and dexamethasone were evaluated. Glycosaminoglycan (GAG) accumulation was measured. A combination of IGF-1 and GDF-5 was selected for further testing based on the results of part I. Chondrocytes from four donors underwent expansion followed by three-dimensional alginate culture for 2 weeks in medium supplemented with 2% or 10% HS with or without IGF-1 and GDF-5. Chondrocytes and their associated matrix were then recovered and cultured for 4 weeks in 12 mm transwells in medium supplemented with 2% or 10% HS with or without IGF-1 and GDF-5 (the same medium used for alginate culture). Biochemical and biomechanical properties of the neocartilage were measured. In part I, GAG accumulation was highest for growth factor combinations including both IGF-1 and GDF-5. In part II, the addition of IGF-1 and GDF-5 to 2% HS resulted in a 12-fold increase in construct thickness compared with 2% HS alone (p < 0.0001). GAG and type II collagen accumulation was significantly higher with IGF-1 and GDF-5. Confined compression

Insulin-like growth factor II messenger RNA-binding protein-3 is an independent prognostic factor in uterine leiomyosarcoma.

PubMed

Yasutake, Nobuko; Ohishi, Yoshihiro; Taguchi, Kenichi; Hiraki, Yuka; Oya, Masafumi; Oshiro, Yumi; Mine, Mari; Iwasaki, Takeshi; Yamamoto, Hidetaka; Kohashi, Kenichi; Sonoda, Kenzo; Kato, Kiyoko; Oda, Yoshinao

2018-04-01

The aim of this study was to identify the prognostic factors of uterine leiomyosarcoma (ULMS). We reviewed 60 cases of surgically resected ULMSs and investigated conventional clinicopathological factors, together with the expression of insulin-like growth factor II messenger RNA-binding protein-3 (IMP3), hormone receptors and cell cycle regulatory markers by immunohistochemistry. Mediator complex subunit 12 (MED12) mutation analysis was also performed. Univariate analyses revealed that advanced stage (P < 0.0001), older age (P = 0.0244) and IMP3 expression (P = 0.0011) were significant predictors of a poor outcome. Multivariate analysis revealed advanced stage (P < 0.0001) and IMP3 (P = 0.0373) as independent predictors of a poor prognosis. Expressions of cell cycle markers and hormone receptors, and MED12 mutations (12% in ULMSs) were not identified as prognostic markers in this study. IMP3 expression in ULMS could be a marker of a poor prognosis. © 2017 John Wiley & Sons Ltd.

Loss of insulin-like growth factor-II imprinting and the presence of screen-detected colorectal adenomas in women.

PubMed

Woodson, Karen; Flood, Andrew; Green, Lisa; Tangrea, Joseph A; Hanson, Jeffrey; Cash, Brooks; Schatzkin, Arthur; Schoenfeld, Phillip

2004-03-03

Loss of imprinting (LOI) of insulin-like growth factor-II (IGF-II) may be an inherited epigenetic trait that is polymorphic in the population, and its presence may predispose an individual to the development of colorectal cancer. We evaluated the association between LOI of IGF-II in normal colonic mucosal samples and adenomas in women participating in a colonoscopy screening study. Among 40 participants, 11 (27.5%) had LOI of IGF-II in their normal colonic mucosal tissue. After adjusting for body mass index and family history of colorectal cancer, LOI status was associated with a fivefold increased risk of adenoma formation (odds ratio = 5.2, 95% confidence interval = 1.0 to 26.7). On average, IGF-II expression was more than threefold higher among women with LOI of IGF-II than among women with normal imprinting status. Our findings support the hypothesis that LOI of IGF-II is an epigenetic trait polymorphic in the population and suggest that LOI of IGF-II may play a role in colorectal cancer. These findings are intriguing and need to be confirmed in larger studies.

FASTRAN II - FATIGUE CRACK GROWTH STRUCTURAL ANALYSIS (IBM PC VERSION)

NASA Technical Reports Server (NTRS)

Newman, J. C.

1994-01-01

Predictions of fatigue crack growth behavior can be made with the Fatigue Crack Growth Structural Analysis (FASTRAN II) computer program. As cyclic loads are applied to a selected crack configuration with an initial crack size, FASTRAN II predicts crack growth as a function of cyclic load history until either a desired crack size is reached or failure occurs. FASTRAN II is based on plasticity-induced crack-closure behavior of cracks in metallic materials and accounts for load-interaction effects, such as retardation and acceleration, under variable-amplitude loading. The closure model is based on the Dugdale model with modifications to allow plastically deformed material to be left along the crack surfaces as the crack grows. Plane stress and plane strain conditions, as well as conditions between these two, can be simulated in FASTRAN II by using a constraint factor on tensile yielding at the crack front to approximately account for three-dimensional stress states. FASTRAN II contains seventeen predefined crack configurations (standard laboratory fatigue crack growth rate specimens and many common crack configurations found in structures); and the user can define one additional crack configuration. The baseline crack growth rate properties (effective stress-intensity factor against crack growth rate) may be given in either equation or tabular form. For three-dimensional crack configurations, such as surface cracks or corner cracks at holes or notches, the fatigue crack growth rate properties may be different in the crack depth and crack length directions. Final failure of the cracked structure can be modelled with fracture toughness properties using either linear-elastic fracture mechanics (brittle materials), a two-parameter fracture criterion (brittle to ductile materials), or plastic collapse (extremely ductile materials). The crack configurations in FASTRAN II can be subjected to either constant-amplitude, variable-amplitude or spectrum loading. The applied

Development and psychometric evaluation of the Personal Growth Initiative Scale-II.

PubMed

Robitschek, Christine; Ashton, Matthew W; Spering, Cynthia C; Geiger, Nathaniel; Byers, Danielle; Schotts, G Christian; Thoen, Megan A

2012-04-01

The original Personal Growth Initiative Scale (PGIS; Robitschek, 1998) was unidimensional, despite theory identifying multiple components (e.g., cognition and behavior) of personal growth initiative (PGI). The present research developed a multidimensional measure of the complex process of PGI, while retaining the brief and psychometrically sound properties of the original scale. Study 1 focused on scale development, including theoretical derivation of items, assessing factor structure, reducing number of items, and refining the scale length using samples of college students. Study 2 consisted of confirmatory factor analysis with 3 independent samples of college students and community members. Lastly, Study 3 assessed test-retest reliability over 1-, 2-, 4-, and 6-week periods and tests of concurrent and discriminant validity using samples of college students. The final measure, the Personal Growth Initiative Scale-II (PGIS-II), includes 4 subscales: Readiness for Change, Planfulness, Using Resources, and Intentional Behavior. These studies provide exploratory and confirmatory evidence for the 4-factor structure, strong internal consistency for the subscales and overall score across samples, acceptable temporal stability at all assessed intervals, and concurrent and discriminant validity of the PGIS-II. Future directions for research and clinical practice are discussed.

Nonmuscle Myosin II Is Required for Internalization of the Epidermal Growth Factor Receptor and Modulation of Downstream Signaling*

PubMed Central

Kim, Jong Hyun; Wang, Aibing; Conti, Mary Anne; Adelstein, Robert S.

2012-01-01

Ligand-induced internalization of the epidermal growth factor receptor (EGFR) is an important process for regulating signal transduction, cellular dynamics, and cell-cell communication. Here, we demonstrate that nonmuscle myosin II (NM II) is required for the internalization of the EGFR and to trigger the EGFR-dependent activation of ERK and AKT. The EGFR was identified as a protein that interacts with NM II by co-immunoprecipitation and mass spectrometry analysis. This interaction requires both the regulatory light chain 20 (RLC20) of NM II and the kinase domain of the EGFR. Two paralogs of NM II, NM II-A, and NM II-B can act to internalize the EGFR, depending on the cell type and paralog content of the cell line. Loss (siRNA) or inhibition (25 μm blebbistatin) of NM II attenuates the internalization of the EGFR and impairs EGFR-dependent activation of ERK and AKT. Both internalization of the EGFR and downstream signaling to ERK and AKT can be partially restored in siRNA-treated cells by introduction of wild type (WT) GFP-NM II, but cannot be restored by motor mutant NM II. Taken together, these results suggest that NM II plays a role in the internalization of the EGFR and EGFR-mediated signaling pathways. PMID:22718763

Recombinant human basic fibroblast growth factor (bFGF) stimulates periodontal regeneration in class II furcation defects created in beagle dogs.

PubMed

Murakami, S; Takayama, S; Kitamura, M; Shimabukuro, Y; Yanagi, K; Ikezawa, K; Saho, T; Nozaki, T; Okada, H

2003-02-01

Several growth factors (or cytokines) have been recently investigated for their use as potential therapeutics for periodontal tissue regeneration. The objective of this study was to evaluate periodontal tissue regeneration, including new bone and cementum formation, following topical application of recombinant basic fibroblast growth factor (bFGF, FGF-2) to furcation class II defects. Twelve furcation class II bone defects were surgically created in six beagle dogs, then recombinant bFGF (30 micro g/site) + gelatinous carrier was topically applied to the bony defects. Six weeks after application, periodontal regeneration was analyzed. In all sites where bFGF was applied, periodontal ligament formation with new cementum deposits and new bone formation was observed histomorphometrically, in amounts greater than in the control sites. Basic FGF-applied sites exhibited significant regeneration as represented by the new bone formation rate (NBR) (83.6 +/- 14.3%), new trabecular bone formation rate (NTBR) (44.1 +/- 9.5%), and new cementum formation rate (NCR) (97.0 +/- 7.5%). In contrast, in the carrier-only sites, the NBR, NTBR, and NCR were 35.4 +/- 8.9%, 16.6 +/- 6.2%, and 37.2 +/- 15.1%, respectively. Moreover, no instances of epithelial down growth, ankylosis, or root resorption were observed in the bFGF-applied sites examined. The present results indicate that topical application of bFGF can enhance considerable periodontal regeneration in artificially created furcation class II bone defects of beagle dogs.

Overexpressed connective tissue growth factor in cardiomyocytes attenuates left ventricular remodeling induced by angiotensin II perfusion.

PubMed

Zhang, Ying; Yan, Hua; Guang, Gong-Chang; Deng, Zheng-Rong

2017-01-01

To evaluate the improving effects of specifically overexpressed connective tissue growth factor (CTGF) in cardiomyocytes on mice with hypertension induced by angiotensin II (AngII) perfusion, 24 transgenic mice with cardiac-restricted overexpression of CTGF (Tg-CTGF) were divided into two equal groups that were perfused with acetic acid and AngII, respectively, for 7 days. Another 24 cage-control wild-type C57BL/6 mice (NLC) were divided and treated identically. Blood pressure was detected by caudal artery cannulation. Cardiac structural and functional changes were observed by echocardiography. Cardiac fibrosis was detected by Masson staining. After AngII perfusion, blood pressures of NLC and Tg-CTGF mice, especially those of the formers, significantly increased. Compared with NLC + AngII group, Tg-CTGF + AngII group had significantly lower left ventricular posterior wall thickness at end-diastole and left ventricular posterior wall thickness at end-systole as well as significantly higher left ventricular end-systolic diameter and left ventricular end-diastolic diameter (P < 0.05). Reverse transcription-polymerase chain reaction (RT-PCR) showed that Tg-CTGF + AngII group had significantly lower collagen I, α-SMA, and TGF-β mRNA expressions in cardiac tissues (P < 0.05). Tg-CTGF can protect AngII-induced cardiac remodeling of mice with hypertension by mitigating inflammatory response. CTGF may be a therapy target for hypertension-induced myocardial fibrosis, but the detailed mechanism still needs in-depth studies.

Effect of recombinant insulin-like growth factor-1 treatment on short-term linear growth in a child with Majewski osteodysplastic primordial dwarfism type II and hepatic insufficiency.

PubMed

Faienza, Maria Felicia; Acquafredda, Angelo; D'Aniello, Mariangela; Soldano, Lucia; Marzano, Flaviana; Ventura, Annamaria; Cavallo, Luciano

2013-01-01

We report the case of a boy affected by severe intrauterine and postnatal growth retardation, microcephaly, facial dysmorphisms and postnecrotic cirrhosis, diagnosed at birth as having Seckel syndrome, and subsequently confirmed as Majewski osteodysplastic primordial dwarfism type II (MOPD II) on the basis of clinical and radiological features of skeletal dysplasia. At our observation (6 years 7 months) he presented height -10.3 standard deviation score (SDS), weight -22.1 SDS, head circumference -8 SDS, delayed bone age of 4 years with respect to chronological age. In consideration of the low levels of insulin-like growth factor-1 (IGF-1) as well as of hepatic insufficiency, we started the treatment with recombinant human IGF-1 (rhIGF-1) at the dose of 0.04 mg/kg in 2 doses/day, with an increase of 0.04 mg/kg after 1 week until the maximum dose of 0.12 mg/kg. We observed an early response to rhIGF-1 treatment, with a shift of height velocity from 1.8 cm/year (-4.6 SDS) at 4 cm/year (-1.9 SDS), and an increase in bone age of 1.5 years during the first 6 months. rhIGF-1 treatment does not seem to be able to replace the physiological action of IGF-1 in patients with MOPD II and hepatic insufficiency, however, it seems to preserve the typical growth pattern of MOPD II patients, avoiding a further widening of the growth deficiency in these subjects.

[Therapeutic use of hematopoietic growth factors. II. GM-CSF and G-CSF].

PubMed

Royer, B; Arock, M

1998-01-01

The second part of this review on haematopoietic growth factors is focused on the therapeutic use of GM-CSF and G-CSF. Such therapeutic applications have raised very great hopes for clinical haematology. However, it should not be forgotten that these haematopoietic growth factors, which are very costly, are powerful two-edged weapons capable of triggering a cascade of reactions, and have a field of activity that often goes beyond the single highly specific property which it is hoped they possess. The risks and costs of their use are currently being evaluated. Waited developments concerning these molecules focus on three axes: a best use of factors already commercialized, especially concerning adaptation of posologies and new indications, the development of hybrid molecules from already known haematopoietic growth factors, possessing the advantages of respective factors, but not their disadvantages, the discovery of new haematopoietic growth factors with potential therapeutic application.

Insulin-like growth factors I and II in starry flounder (Platichthys stellatus): molecular cloning and differential expression during embryonic development.

PubMed

Xu, Yongjiang; Zang, Kun; Liu, Xuezhou; Shi, Bao; Li, Cunyu; Shi, Xueying

2015-02-01

In order to elucidate the possible roles of insulin-like growth factors I and II (IGF-I and IGF-II) in the embryonic development of Platichthys stellatus, their cDNAs were isolated and their spatial expression pattern in adult organs and temporal expression pattern throughout embryonic development were examined by quantitative real-time PCR assay. The IGF-I cDNA sequence was 1,268 bp in length and contained an open reading frame (ORF) of 558 bp, which encoded 185 amino acid residues. With respect to IGF-II, the full-length cDNA was 899 bp in length and contained a 648-bp ORF, which encoded 215 amino acid residues. The amino acid sequences of IGF-I and IGF-II exhibited high identities with their fish counterparts. The highest IGF-I mRNA level was found in the liver for both sexes, whereas the IGF-II gene was most abundantly expressed in female liver and male liver, gill, and brain. The sex-specific and spatial expression patterns of IGF-I and IGF-II mRNAs are thought to be related to the sexually dimorphic growth and development of starry flounder. Both IGF-I and IGF-II mRNAs were detected in unfertilized eggs, which indicated that IGF-I and IGF-II were parentally transmitted. Nineteen embryonic development stages were tested. IGF-I mRNA level remained high from unfertilized eggs to low blastula followed by a significant decrease at early gastrula and then maintained a lower level. In contrast, IGF-II mRNA level was low from unfertilized eggs to high blastula and peaked at low blastula followed by a gradual decrease. Moreover, higher levels of IGF-I mRNA than that of IGF-II were found from unfertilized eggs to high blastula, vice versa from low blastula to newly hatched larva, and the different expression pattern verified the differential roles of IGF-I and IGF-II in starry flounder embryonic development. These results could help in understanding the endocrine mechanism involved in the early development and growth of starry flounder.

Autosomal Dominant Growth Hormone Deficiency (Type II).

PubMed

Alatzoglou, Kyriaki S; Kular, Dalvir; Dattani, Mehul T

2015-06-01

Isolated growth hormone deficiency (IGHD) is the commonest pituitary hormone deficiency resulting from congenital or acquired causes, although for most patients its etiology remains unknown. Among the known factors, heterozygous mutations in the growth hormone gene (GH1) lead to the autosomal dominant form of GHD, also known as type II GHD. In many cohorts this is the commonest form of congenital isolated GHD and is mainly caused by mutations that affect the correct splicing of GH-1. These mutations cause skipping of the third exon and lead to the production of a 17.5-kDa GH isoform that exerts a dominant negative effect on the secretion of the wild type GH. The identification of these mutations has clinical implications for the management of patients, as there is a well-documented correlation between the severity of the phenotype and the increased expression of the 17.5-kDa isoform. Patients with type II GHD have a variable height deficit and severity of GHD and may develop additional pituitary hormone defiencies over time, including ACTH, TSH and gonadotropin deficiencies. Therefore, their lifelong follow-up is recommended. Detailed studies on the effect of heterozygous GH1 mutations on the trafficking, secretion and action of growth hormone can elucidate their mechanism on a cellular level and may influence future treatment options for GHD type II.

Effect of basic fibroblast growth factor and transforming growth factor β1 on the healing of reconstructed dura by carbon dioxide laser soldering in minipigs.

PubMed

Zhong, Hong-liang; Wang, Zhen-min; Yang, Zhi-jun; Zhao, Fu; Wang, Bo; Wang, Zhong-cheng; Liu, Pi-nan

2012-02-01

Carbon dioxide (CO2) laser soldering is an alternative technique for tissue bonding. Basic fibroblast growth factor (bFGF) and transforming growth factor β(1) (TGFβ(1)) are two key factors for wound healing. This study was performed to demonstrate the efficacy of CO2 laser soldering for dural reconstruction and the effect of bFGF and TGFβ(1) on healing. In Part I, 10 minipigs were randomized into two equal groups. Dural defects were reconstructed by conventional fibrin glue bonding (group I(a)) or CO2 laser soldering (group I(b)). The reconstructed dura was subjected to burst pressure (BP) measurement and immunohistochemical staining after 1 week. In Part II, 36 minipigs were randomized into three equal groups. Dural reconstruction was achieved by CO2 laser soldering. Exogenous bFGF (group II(b)) or TGFβ(1) (group II(c)) was administered while group II(a) served as a control group. The specimens were subjected to BP measurement after 1, 2, 3, and 4 weeks, respectively. In Part I, the dura specimens displayed positive staining of only bFGF in group I(a) and of both bFGF and TGFβ(1) in group I(b). Group I(b) showed higher BP than group I(a) ((98.00 ± 21.41) mmHg vs. (70.80 ± 15.09) mmHg, respectively; P < 0.05). In Part II, BP of group II(c) was significantly higher than that of group II(a) (P < 0.01). The BP of group II(a) trended toward stabilization after 3 weeks of growth, while that of groups II(b) and II(c) trended toward stabilization after 2 weeks of growth. CO2 laser soldering is a reliable technique for dural reconstruction. The superior healing of dural reconstruction by CO2 laser soldering may be related to higher expression of bFGF and TGFβ(1), and CO2 lasers may stimulate their secretion. Exogenous bFGF or TGFβ(1) may improve healing by shortening the wound healing time, and exogenous TGFβ(1) may improve the tensile strength.

Insulin-like growth factor-I receptor activity is essential for Kaposi's sarcoma growth and survival.

PubMed

Catrina, S-B; Lewitt, M; Massambu, C; Dricu, A; Grünler, J; Axelson, M; Biberfeld, P; Brismar, K

2005-04-25

Kaposi's sarcoma (KS) is a highly vascular tumour and is the most common neoplasm associated with human immunodeficiency virus (HIV-1) infection. Growth factors, in particular vascular endothelial growth factor (VEGF), have been shown to play an important role in its development. The role of insulin-like growth factors (IGFs) in the pathophysiology of different tumours led us to evaluate the role of IGF system in KS. The IGF-I receptors (IGF-IR) were identified by immunohistochemistry in biopsies taken from patients with different AIDS/HIV-related KS stages and on KSIMM cells (an established KS-derived cell line). Insulin-like growth factor-I is a growth factor for KSIMM cells with a maximum increase of 3H-thymidine incorporation of 130 +/- 27.6% (P < 0.05) similar to that induced by VEGF and with which it is additive (281 +/- 13%) (P < 0.05). Moreover, specific blockade of the receptor (either by alpha IR3 antibody or by picropodophyllin, a recently described selective IGF-IR tyrosine phosphorylation inhibitor) induced KSIMM apoptosis, suggesting that IGF-IR agonists (IGF-I and -II) mediate antiapoptotic signals for these cells. We were able to identify an autocrine loop essential for KSIMM cell survival in which IGF-II is the IGF-IR agonist secreted by the cells. In conclusion, IGF-I pathway inhibition is a promising therapeutical approach for KS tumours.

Intestinal hormones and growth factors: Effects on the small intestine

PubMed Central

Drozdowski, Laurie; Thomson, Alan BR

2009-01-01

There are various hormones and growth factors which may modify the intestinal absorption of nutrients, and which might thereby be useful in a therapeutic setting, such as in persons with short bowel syndrome. In partI, we focus first on insulin-like growth factors, epidermal and transferring growth factors, thyroid hormones and glucocorticosteroids. Part II will detail the effects of glucagon-like peptide (GLP)-2 on intestinal absorption and adaptation, and the potential for an additive effect of GLP2 plus steroids. PMID:19152442

Growth factor effects on costal chondrocytes for tissue engineering fibrocartilage

PubMed Central

Johns, D.E.; Athanasiou, K.A.

2010-01-01

Tissue engineered fibrocartilage could become a feasible option for replacing tissues like the knee meniscus or temporomandibular joint disc. This study employed five growth factors insulin-like growth factor-I, transforming growth factor-β1, epidermal growth factor, platelet-derived growth factor-BB, and basic fibroblast growth factor in a scaffoldless approach with costal chondrocytes, attempting to improve biochemical and mechanical properties of engineered constructs. Samples were quantitatively assessed for total collagen, glycosaminoglycans, collagen type I, collagen type II, cells, compressive properties, and tensile properties at two time points. Most treated constructs were worse than the no growth factor control, suggesting a detrimental effect, but the IGF treatment tended to improve the constructs. Additionally, the 6wk time point was consistently better than 3wks, with total collagen, glycosaminoglycans, and aggregate modulus doubling during this time. Further optimization of the time in culture and exogenous stimuli will be important in making a more functional replacement tissue. PMID:18597118

The kangaroo cation-independent mannose 6-phosphate receptor binds insulin-like growth factor II with low affinity.

PubMed

Yandell, C A; Dunbar, A J; Wheldrake, J F; Upton, Z

1999-09-17

The mammalian cation-independent mannose 6-phosphate receptor (CI-MPR) binds mannose 6-phosphate-bearing glycoproteins and insulin-like growth factor (IGF)-II. However, the CI-MPR from the opossum has been reported to bind bovine IGF-II with low affinity (Dahms, N. M., Brzycki-Wessell, M. A., Ramanujam, K. S., and Seetharam, B. (1993) Endocrinology 133, 440-446). This may reflect the use of a heterologous ligand, or it may represent the intrinsic binding affinity of this receptor. To examine the binding of IGF-II to a marsupial CI-MPR in a homologous system, we have previously purified kangaroo IGF-II (Yandell, C. A., Francis, G. L., Wheldrake, J. F., and Upton, Z. (1998) J. Endocrinol. 156, 195-204), and we now report the purification and characterization of the CI-MPR from kangaroo liver. The interaction of the kangaroo CI-MPR with IGF-II has been examined by ligand blotting, radioreceptor assay, and real-time biomolecular interaction analysis. Using both a heterologous and homologous approach, we have demonstrated that the kangaroo CI-MPR has a lower binding affinity for IGF-II than its eutherian (placental mammal) counterparts. Furthermore, real-time biomolecular interaction analysis revealed that the kangaroo CI-MPR has a higher affinity for kangaroo IGF-II than for human IGF-II. The cDNA sequence of the kangaroo CI-MPR indicates that there is considerable divergence in the area corresponding to the IGF-II binding site of the eutherian receptor. Thus, the acquisition of a high-affinity binding site for regulating IGF-II appears to be a recent event specific to the eutherian lineage.

Role of epidermal growth factor receptor and endoplasmic reticulum stress in vascular remodeling induced by angiotensin II.

PubMed

Takayanagi, Takehiko; Kawai, Tatsuo; Forrester, Steven J; Obama, Takashi; Tsuji, Toshiyuki; Fukuda, Yamato; Elliott, Katherine J; Tilley, Douglas G; Davisson, Robin L; Park, Joon-Young; Eguchi, Satoru

2015-06-01

The mechanisms by which angiotensin II (AngII) elevates blood pressure and enhances end-organ damage seem to be distinct. However, the signal transduction cascade by which AngII specifically mediates vascular remodeling such as medial hypertrophy and perivascular fibrosis remains incomplete. We have previously shown that AngII-induced epidermal growth factor receptor (EGFR) transactivation is mediated by disintegrin and metalloproteinase domain 17 (ADAM17), and that this signaling is required for vascular smooth muscle cell hypertrophy but not for contractile signaling in response to AngII. Recent studies have implicated endoplasmic reticulum (ER) stress in hypertension. Interestingly, EGFR is capable of inducing ER stress. The aim of this study was to test the hypothesis that activation of EGFR and ER stress are critical components required for vascular remodeling but not hypertension induced by AngII. Mice were infused with AngII for 2 weeks with or without treatment of EGFR inhibitor, erlotinib, or ER chaperone, 4-phenylbutyrate. AngII infusion induced vascular medial hypertrophy in the heart, kidney and aorta, and perivascular fibrosis in heart and kidney, cardiac hypertrophy, and hypertension. Treatment with erlotinib as well as 4-phenylbutyrate attenuated vascular remodeling and cardiac hypertrophy but not hypertension. In addition, AngII infusion enhanced ADAM17 expression, EGFR activation, and ER/oxidative stress in the vasculature, which were diminished in both erlotinib-treated and 4-phenylbutyrate-treated mice. ADAM17 induction and EGFR activation by AngII in vascular cells were also prevented by inhibition of EGFR or ER stress. In conclusion, AngII induces vascular remodeling by EGFR activation and ER stress via a signaling mechanism involving ADAM17 induction independent of hypertension. © 2015 American Heart Association, Inc.

Expression of the genes for insulin-like growth factors and their receptors in bone during skeletal growth

NASA Technical Reports Server (NTRS)

Bikle, D. D.; Harris, J.; Halloran, B. P.; Roberts, C. T.; Leroith, D.; Morey-Holton, E.

1994-01-01

Insulin-like growth factors (IGF) are important regulators of skeletal growth. To determine whether the capacity to produce and respond to these growth factors changes during skeletal development, we measured the protein and mRNA levels for IGF-I, IGF-II, and their receptors (IGF-IR and IGF-IIR, respectively) in the tibia and femur of rats before and up to 28 mo after birth. The mRNA levels remained high during fetal development but fell after birth, reaching a nadir by 3-6 wk. This fall was most pronounced for IGF-II and IGF-IIR mRNA and least pronounced for IGF-I mRNA. However, after 6 wk, both IGF-I and IGF-IR mRNA levels recovered toward the levels observed at birth. In the prenatal bones, the signals for the mRNAs of IGF-II and IGF-IIR were stronger than the signals for the mRNAs of IGF-I and IGF-IR, although the content of IGF-I was three- to fivefold greater than that of IGF-II. IGF-II levels fell postnatally, whereas the IGF-I content rose after birth such that the ratio IGF-I/IGF-II continued to increase with age. We conclude that, during development, rat bone changes its capacity to produce and respond to IGFs with a progressive trend toward the dominance of IGF-I.

Why is coronary collateral growth impaired in type II diabetes and the metabolic syndrome?

PubMed Central

Rocic, Petra

2012-01-01

Type II diabetes and the metabolic syndrome are strong predictors of severity of occlusive coronary disease and poorer outcomes of coronary revascularization therapies. Coronary collateral growth can provide an alternative or accessory pathway of revascularization. However, collateral growth is impaired in type II diabetes and the metabolic syndrome. Although many factors necessary for collateral growth are known and many interventions have shown promising results in animal studies, not a single attempt to induce coronary collateral growth in human clinical trials has led to satisfactory results. Accordingly, the first part of this review outlines the known deleterious effects of diabetes and the metabolic syndrome on factors necessary for collateral growth, including pro-angiogenic growth factors, endothelial function, the redox state of the coronary circulation, intracellular signaling, leukocytes and bone marrow-derived progenitors cells. The second section highlights the gaps in our current knowledge of how these factors interact with the radically altered environment of the coronary circulation in diabetes and the metabolic syndrome. The interplay between these pathologies and inadequately explored areas related to the temporal regulation of collateral remodeling and the roles of the extracellular matrix, vascular cell phenotype and pro-inflammatory cytokines are emphasized with implications to development of efficient therapies. PMID:22342811

Effects of aluminum trichloride on the cartilage stimulatory growth factors in rats.

PubMed

Zhang, Fan; Sun, Xudong; Yu, Hongyan; Yang, Xu; Song, Miao; Han, Yanfei; Li, Yanfei; Zhu, Yanzhu

2017-02-01

Aluminum (Al) is considered to be a potentially toxic metal and inhibits cartilage formation. Transforming growth factor β1 (TGF-β1) and bone morphogenetic protein 2 (BMP-2) are cartilage stimulatory growth factors, which play important roles in regulating the cartilage formation. To investigate the effects of aluminum trichloride (AlCl 3 ) on the regulation of cartilage formation. Eighty Wistar rats were orally exposed to 0 (control group), 0.4 g/L (low-dose group), 0.8 g/L (mid-dose group) and 1.6 g/L (high-dose group) AlCl 3 for 120 days, respectively. The rats body weight were decreased, the cartilage histological structure were disrupted, the cartilage and serum contents of Al and the serum level of C-telopeptide of type II collagen were all increased, the serum level of type II collagen (Col II) and alkaline phosphatase (ALP), and the mRNA expressions of TGF-β1, BMP-2, ALP and Col II were all decreased in the AlCl 3 -treated groups compared with those in control group. These results indicate that AlCl 3 inhibits the cartilage formation through inhibition of the cartilage stimulatory growth factors expressions.

Transforming growth factor alpha, Shope fibroma growth factor, and vaccinia growth factor can replace myxoma growth factor in the induction of myxomatosis in rabbits.

PubMed

Opgenorth, A; Nation, N; Graham, K; McFadden, G

1993-02-01

The epidermal growth factor (EGF) homologues encoded by vaccinia virus, myxoma virus, and malignant rabbit fibroma virus have been shown to contribute to the pathogenicity of virus infection upon inoculation of susceptible hosts. However, since the primary structures of these growth factors and the disease profiles induced by different poxvirus genera vary substantially, the degree to which the various EGF homologues perform similar roles in viral pathogenesis remains unclear. In order to determine whether different EGF-like growth factors can perform qualitatively similar functions in the induction of myxomatosis in rabbits, we created recombinant myxoma virus variants in which the native growth factor, myxoma growth factor (MGF), was disrupted and replaced with either vaccinia virus growth factor, Shope fibroma growth factor, or rat transforming growth factor alpha. Unlike the control virus containing an inactivated MGF gene, which caused marked attenuation of the disease syndrome and substantially less proliferation of the epithelial cell layers in the conjunctiva and respiratory tract, the recombinant myxoma virus strains expressing heterologous growth factors produced infections which were both clinically and histopathologically indistinguishable from wild-type myxomatosis. We conclude that these poxviral and cellular EGF-like growth factors, which are diverse with respect to primary structure and origin, have similar biological functions in the context of myxoma virus pathogenesis and are mitogenic for the same target cells.

Effect of iron deficiency on the expression of insulin-like growth factor-II and its receptor in neuronal and glial cells.

PubMed

Morales González, E; Contreras, I; Estrada, J A

2014-09-01

Many studies have demonstrated that iron deficiency modifies the normal function of the central nervous system and alters cognitive abilities. When cellular damage occurs in the central nervous system, neuroprotective mechanisms, such as the production of neurotrophic factors, are essential in order for nervous tissue to function correctly. Insulin-like growth factor II (IGF- II) is a neurotrophic factor that was recently shown to be involved in the normal functioning of cognitive processes in animal models. However, the impact of iron deficiency on the expression and function of this molecule has not yet been clarified. Mixed primary cell cultures from the central nervous system were collected to simulate iron deficiency using deferoxamine. The expression of IGF-I, IGF-II, IGF-IR, and IGF-IIR was determined with the western blot test. We observed increased expression of IGF-II, along with a corresponding decrease in the expression of IGF-IIR, in iron-deficient mixed primary cell cultures. We did not observe alterations in the expression of these proteins in isolated microglia or neuronal cultures under the same conditions. We did not detect differences in the expression of IGF-I and IGF-IR in iron-deficient cultures. In vitro iron deficiency increases the expression of IGF-II in mixed glial cell cultures, which may have a beneficial effect on brain tissue homeostasis in a situation in which iron availability is decreased. Copyright © 2013 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.

Insulin-Like Growth Factor Regulates Peak Bone Mineral Density in Mice by Both Growth Hormone-Dependent and -Independent Mechanisms

PubMed Central

Mohan, Subburaman; Richman, Charmaine; Guo, Rongqing; Amaar, Yousef; Donahue, Leah Rea; Wergedal, Jon; Baylink, David J.

2010-01-01

To evaluate the relative contribution of the GH/IGF axis to the development of peak bone mineral density (BMD), we measured skeletal changes in IGF-I knockout (KO), IGF-II KO, and GH-deficient lit/lit mice and their corresponding control mice at d 23 (prepubertal), 31 (pubertal), and 56 (postpubertal) in the entire femur by dual energy x-ray absorptiometry and in the mid-diaphysis by peripheral quantitative computed tomography. Lack of growth factors resulted in different degrees of failure of skeletal growth depending on the growth period and the growth factor involved. At d 23, femoral length, size, and BMD were reduced by 25–40%, 15–17%, and 8–10%, respectively, in mice deficient in IGF-I, IGF-II, and GH compared with the control mice. During puberty, BMD increased by 40% in control mice and by 15% in IGF-II KO and GH-deficient mice, whereas it did not increase in the IGF-I KO mice. Disruption of IGF-I, but not IGF-II, completely prevented the periosteal expansion that occurs during puberty, whereas it was reduced by 50% in GH-deficient mice. At d 56, femoral length, size, and BMD were reduced by 40–55%, 11–18%, and 25–32%, respectively, in mice deficient in IGF-I, IGF-II, and GH compared with the control mice. Our data demonstrate that: 1) mice deficient in IGF-I exhibit a greater impairment in bone accretion than mice deficient in IGF-II or GH; 2) GH/IGF-I, but not IGF-II, is critical for puberty-induced bone growth; and 3) IGF-I effects on bone accretion during prepuberty are mediated predominantly via mechanisms independent of GH, whereas during puberty they are mediated via both GH-dependent and GH-independent mechanisms. PMID:12586770

Associations of blood levels of insulin-like growth factor (IGF)-I, IGF-II and IGF binding protein (IGFBP)-3 in schizophrenic Arab subjects.

PubMed

Akanji, Abayomi O; Ohaeri, Jude U; Al-Shammri, Suhail A; Fatania, Hasmukh R

2007-01-01

Insulin-like growth factors (IGFs) are believed to be important in brain development and repair following neuronal damage. It is also speculated that IGFs are involved in the association of foetal and pre-adult growth with schizophrenia (SZ). The aim of this study was to assess levels of IGF-I, IGF-II and IGF binding protein (IGFBP)-3 and their associations in male Arab patients with SZ (n=53) and healthy control subjects (HC; n=52). Anthropometric and demographic data were collected for each subject for whom blood specimens were analysed for serum lipoproteins, apolipoprotein B (apoB), IGF-I, IGF-II and IGFBP-3. The SZ group had lower serum total cholesterol, apoB and uric acid levels than the HC group (p<0.05). IGF-II levels were significantly higher in the SZ group (p=0.02) and correlated positively with levels of atherogenic lipoproteins--total cholesterol, low-density lipoprotein, apoB--and IGFBP-3. The pattern of correlations between the IGFs and the various parameters differed somewhat between the HC and SZ groups. These results demonstrate that IGF-II levels are increased in patients with SZ and show significant associations with atherogenic lipoproteins. We suggest a possible link between IGF-II metabolism and atherogenesis in SZ.

Significance of abnormal serum binding of insulin-like growth factor II in the development of hypoglycemia in patients with non-islet-cell tumors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Daughaday, W.H.; Kapadia, M.

1989-09-01

The authors reported that serum and tumor from a hypoglycemic patient with a fibrosarcoma contained insulin-like growth factor II (IGF-II), mostly in a large molecular form designated big IGF-II. They now describe two additional patients with non-islet-cell tumor with hypoglycemia (NICTH) whose sera contained big IGF-II. Removal of the tumor eliminated most of the big IGF-II from the sera of two patients. Because specific IGF-binding proteins modify the bioactivity of IGFs, the sizes of the endogenous IGF-binding protein complexes were determined after neutral gel filtration through Sephadex G-200. Normally about 75% of IGFs are carried as a ternary complex ofmore » 150 kDa consisting of IGF, a growth hormone (GH)-dependent IGF-binding protein, and an acid-labile complexing component. The three patients with NICTH completely lacked the 150-kDa complex. IGF-II was present as a 60-kDa complex with variable contributions of smaller complexes. In the immediate postoperative period, a 110-kDa complex appeared rather than the expected 150-kDa complex. Abnormal IGF-II binding may be important in NICTH because the 150-kDa complexes cross the capillary membrane poorly. The smaller complexes present in our patients' sera would be expected to enter interstitial fluid readily, and a 4- to 5-fold increase in the fraction of IGFs reaching the target cells would result.« less

Epidermal growth factor stimulates mouse placental lactogen I but inhibits mouse placental lactogen II secretion in vitro.

PubMed Central

Yamaguchi, M; Ogren, L; Endo, H; Thordarson, G; Kensinger, R; Talamantes, F

1992-01-01

This study was undertaken to determine whether epidermal growth factor (EGF) regulates the secretion of mouse placental lactogen (mPL)-I and mPL-II. Primary cell cultures were prepared from placentas from days 7, 9, and 11 of pregnancy and cultured for up to 5 days. Addition of EGF (20 ng/ml) to the medium resulted in significant stimulation of mPL-I secretion by the second day of culture in cells from days 7 and 9 of pregnancy and significant inhibition of mPL-II secretion by the third or fourth day of culture in cells from days 7, 9, and 11. Dose-response studies carried out with cells from day 7 of pregnancy demonstrated that the minimum concentration of EGF that stimulated mPL-I secretion and inhibited mPL-II secretion was 1.0 ng/ml. EGF did not affect the DNA content of the cells or cell viability, assessed by trypan blue exclusion, nor did it have a general effect on protein synthesis. There are three types of PL-containing giant cells in mouse placental cell cultures: cells that contain either mPL-I or mPL-II and cells that contain both hormones. Immunocytochemical analysis and the reverse hemolytic plaque assay indicated that EGF treatment was accompanied by a significant increase in the number of cells that produce mPL-I, but among the PL cells that contained mPL-I, there was no change in the fraction of cells that contained only mPL-I or the fraction that contained both mPL-I and mPL-II. In contrast, EGF treatment did affect the distribution of mPL-II among PL cells. In control cultures, about 75% of the cells that contained mPL-II also contained mPL-I, but in EGF-treated cultures, all of the cells that contained mPL-II also contained mPL-I. These data suggest that EGF regulates mPL-I and mPL-II secretion at least partly by regulating PL cell differentiation. PMID:1454826

Growth Factors and COX2 Expression in Canine Perivascular Wall Tumors.

PubMed

Avallone, G; Stefanello, D; Boracchi, P; Ferrari, R; Gelain, M E; Turin, L; Tresoldi, E; Roccabianca, P

2015-11-01

Canine perivascular wall tumors (PWTs) are a group of subcutaneous soft tissue sarcomas developing from vascular mural cells. Mural cells are involved in angiogenesis through a complex crosstalk with endothelial cells mediated by several growth factors and their receptors. The evaluation of their expression may have relevance since they may represent a therapeutic target in the control of canine PWTs. The expression of vascular endothelial growth factor (VEGF) and receptors VEGFR-I/II, basic fibroblast growth factor (bFGF) and receptor Flg, platelet-derived growth factor B (PDGFB) and receptor PDGFRβ, transforming growth factor β1 (TGFβ1) and receptors TGFβR-I/II, and cyclooxygenase 2 (COX2) was evaluated on frozen sections of 40 PWTs by immunohistochemistry and semiquantitatively scored to identify their potential role in PWT development. Statistical analysis was performed to analyze possible correlations between Ki67 labeling index and the expression of each molecule. Proteins of the VEGF-, PDGFB-, and bFGF-mediated pathways were highly expressed in 27 (67.5%), 30 (75%), and 19 (47.5%) of 40 PWTs, respectively. Proteins of the TGFβ1- and COX2-mediated pathways were highly expressed in 4 (10%) and 14 (35%) of 40 cases. Statistical analysis identified an association between VEGF and VEGFR-I/II (P = .015 and .003, respectively), bFGF and Flg (P = .038), bFGF and PDGFRβ (P = .003), and between TGFβ1 and COX2 (P = .006). These findings were consistent with the mechanisms that have been reported to play a role in angiogenesis and in tumor development. No association with Ki67 labeling index was found. VEGF-, PDGFB-, and bFGF-mediated pathways seem to have a key role in PWT development and growth. Blockade of tyrosine kinase receptors after surgery could represent a promising therapy with the aim to reduce the PWT relapse rate and prolong the time to relapse. © The Author(s) 2015.

Fatigue Crack Growth Rate and Stress-Intensity Factor Corrections for Out-of-Plane Crack Growth

NASA Technical Reports Server (NTRS)

Forth, Scott C.; Herman, Dave J.; James, Mark A.

2003-01-01

Fatigue crack growth rate testing is performed by automated data collection systems that assume straight crack growth in the plane of symmetry and use standard polynomial solutions to compute crack length and stress-intensity factors from compliance or potential drop measurements. Visual measurements used to correct the collected data typically include only the horizontal crack length, which for cracks that propagate out-of-plane, under-estimates the crack growth rates and over-estimates the stress-intensity factors. The authors have devised an approach for correcting both the crack growth rates and stress-intensity factors based on two-dimensional mixed mode-I/II finite element analysis (FEA). The approach is used to correct out-of-plane data for 7050-T7451 and 2025-T6 aluminum alloys. Results indicate the correction process works well for high DeltaK levels but fails to capture the mixed-mode effects at DeltaK levels approaching threshold (da/dN approximately 10(exp -10) meter/cycle).

Regulation of cell growth by redox-mediated extracellular proteolysis of platelet-derived growth factor receptor beta.

PubMed

Okuyama, H; Shimahara, Y; Kawada, N; Seki, S; Kristensen, D B; Yoshizato, K; Uyama, N; Yamaoka, Y

2001-07-27

Redox-regulated processes are important elements in various cellular functions. Reducing agents, such as N-acetyl-l-cysteine (NAC), are known to regulate signal transduction and cell growth through their radical scavenging action. However, recent studies have shown that reactive oxygen species are not always involved in ligand-stimulated intracellular signaling. Here, we report a novel mechanism by which NAC blocks platelet-derived growth factor (PDGF)-induced signaling pathways in hepatic stellate cells, a fibrogenic player in the liver. Unlike in vascular smooth muscle cells, we found that reducing agents, including NAC, triggered extracellular proteolysis of PDGF receptor-beta, leading to desensitization of hepatic stellate cells toward PDGF-BB. This effect was mediated by secreted mature cathepsin B. In addition, type II transforming growth factor-beta receptor was also down-regulated. Furthermore, these events seemed to cause a dramatic improvement of rat liver fibrosis. These results indicated that redox processes impact the cell's response to growth factors by regulating the turnover of growth factor receptors and that "redox therapy" is promising for fibrosis-related disease.

Media composition: growth factors.

PubMed

Hegde, Aparna; Behr, Barry

2012-01-01

Despite the fact that the fundamental principle underlying the most common method of culture media constitution is that of mimicking the natural environment of the preimplantation embryo, one major difference that remains between current embryo culture media and in vivo conditions is the absence of growth factors in vitro. Numerous growth factors are known to be present in the in vivo environment of human and nonhuman preimplantation embryos, often with peak concentrations corresponding to when fertilization and preimplantation embryo growth would occur. Although these growth factors are found in very small concentrations, they have a profound effect on tissue growth and differentiation through attachment to factor-specific receptors on cell surfaces. Receptors for many different growth factors have also been detected in human preimplantation embryos. Preimplantation embryos themselves express many growth factors. The growth factors and receptors are metabolically costly to produce, and thus their presence in the environment of the preimplantation embryo and in the embryo respectively strongly implies that embryos are designed to encounter and respond to the corresponding factors. Studies of embryo coculture also indirectly suggest that growth factors can improve in vitro development. Several animal and human studies attest to a probable beneficial effect of addition of growth factors to culture media. However, there is still ambiguity regarding the exact role of growth factors in embryonic development, the optimal dose of growth factors to be added to culture media, the combinatorial effect and endocrine of growth factors in embryonic development.

Insulin-like growth factors (IGF-I, free IGF-I and IGF-II) and insulin-like growth factor binding proteins (IGFBP-2, IGFBP-3, IGFBP-6, and ALS) in blood circulation.

PubMed

Yu, H; Mistry, J; Nicar, M J; Khosravi, M J; Diamandis, A; van Doorn, J; Juul, A

1999-01-01

Insulin-like growth factors (IGFs) and IGF binding proteins (IGFBPs) play an important role in cell growth and differentiation. Clinical and epidemiological studies have indicated that measuring IGFs and IGFBPs in blood has potential implications in assessing growth-related abnormalities and risks of certain types of cancer. To facilitate the application, we reported a large collection of reference ranges of IGFs and IGFBPs in normal population and evaluations of these molecules in serum and plasma as well as the impact of freeze-thaw cycles on the measurement. IGF-I, IGFBP-3 andALS showed a similar pattern of change associated with age. Levels of these molecules were low at birth and increased with age through puberty. After puberty the levels declined slowly with age. Overall, IGF-I, IGFBP-3 and ALS were slightly higher in females than in males. Free IGF-I accounted for about 1% of the total IGF-I and its variation with age was similar to total IGF-I. IGF-II levels were also increased with age from birth to puberty, but became stable after puberty. There was little difference in IGF-II levels between genders. IGFBP-2 levels declined with age from birth to puberty. Levels of IGFBP-6 in contrast were increased with age. These IGF binding proteins were higher in males than in females. IGFs, IGFBP-3 and ALS were 5-10% higher in serum than in plasma. IGFBP-2 and IGFBP-6 differed substantially between serum and plasma. Freeze-thaw treatment up to five cycles had little impact on plasma levels of IGFs and IGFBP-3. Our observations suggest that levels of IGFs and their binding proteins are varied with age, gender, and types of specimen and that these variations need to be taken into consideration when IGFs and their binding proteins are utilized in clinic and research.

Coordinate tropic hormone regulation of mRNAs for insulin-like growth factor II and the cholesterol side-chain-cleavage enzyme, P450scc [corrected], in human steroidogenic tissues.

PubMed Central

Voutilainen, R; Miller, W L

1987-01-01

Insulin-like growth factors (IGFs) are single-chain polypeptides important for cell proliferation and growth. IGFs are produced in several tissues, suggesting that they function in a paracrine or autocrine fashion as well as functioning as endocrine hormones. We studied the hormonal regulation of IGF-I and IGF-II mRNA in human steroidogenic tissues. In cultured human ovarian granulosa cells, follicle-stimulating hormone, human chorionic gonadotropin, and dibutyryl cAMP increased IGF-II mRNA, but corticotropin [adrenocorticotropic hormone (ACTH)], chorionic somatomammotropin, growth hormone, prolactin, dexamethasone, estradiol, and progesterone had no effect. In cultured human fetal adrenal cells, ACTH and dibutyryl cAMP increased IGF-II mRNA accumulation, but human chorionic gonadotropin and angiotensin II did not. The same five size species of IGF-II mRNA were detected in transfer blots of RNA from granulosa cells and fetal adrenal cells, and all of these increased after hormonal stimuli. Dibutyryl cAMP also increased IGF-II mRNA accumulation in cultured human placental cells. Accumulation of mRNA for the cholesterol side-chain-cleavage monooxygenase [P450scc [corrected]; cholesterol, reduced-adrenal-ferredoxin:oxygen oxidoreductase (side-chain-cleaving), EC 1.14.15.6] was regulated in parallel with IGF-II mRNA in all these steroidogenic tissues. IGF-I mRNA was not detected in transfer blots of these RNAs, and the minimal amounts detected in dot blots showed no detectable change after any of the hormonal stimuli studied. The data indicate that the IGF-II gene is expressed in human steroidogenic tissues and is regulated by cAMP. These data suggest that IGF-II may act in an autocrine or paracrine fashion to stimulate the adrenal and gonadal growth stimulated by ACTH and gonadotropins, respectively. Images PMID:3031644

Insulin-like growth factor (IGF)-I, IGF-II and IGF-binding protein (IGFBP)-3 levels in Arab subjects with coronary heart disease.

PubMed

Akanji, A O; Suresh, C G; Al-Radwan, R; Fatania, H R

2007-01-01

Insulin-like growth factors (IGF-I, IGF-II) and their binding protein (IGFBP-3) may be risk markers for coronary heart disease (CHD). This study aimed to assess the levels and determinants of the serum levels of IGF-I, IGF-II and IGFBP-3 in Arab patients with established CHD. Two groups of subjects were matched for age, gender, BMI and waist-hip ratio (WHR): (i) CHD (n = 105), median age 51.0 (range 40.0-60.0) years; (ii) controls (n = 97) aged 49.0 (range 37.0-60.0) years. We measured fasting serum levels of glucose and lipoproteins (total cholesterol, triglycerides, LDL, HDL, apo B), insulin, HOMA-IR, IGF-I, IGF-II and IGFBP-3 and compared the results between groups. The effects of body mass and the metabolic syndrome (MS) on IGF levels were also examined, and linear correlations were sought between the various parameters. The levels of IGF-I, IGF-II and IGFBP-3 were significantly lower (all p<0.01) for the CHD group than for the control group. These differences were not influenced by BMI or with the presence of MS. In CHD, there were no significant correlations between levels of IGF-I and IGF-II and age, BMI, WHR, lipoprotein concentrations and insulin sensitivity, although IGFBP-3 had weakly significant relationships with some of the lipoproteins. Levels of IGF-I, IGF-II and IGFBP3 are reduced in male Arab patients with CHD, and did not appear influenced by traditional CHD risk factors such as age, BMI, insulin sensitivity and presence of MS. Perturbations in the IGF/IGFBP-3 axis may be potential additional targets for pharmacological manipulation in CHD.

Characterization of the growth of murine fibroblasts that express human insulin receptors. II. Interaction of insulin with other growth factors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Randazzo, P.A.; Jarett, L.

1990-09-01

The effects of insulin-like growth factor-1 (IGF-1), epidermal growth factor (EGF), platelet-derived growth factor (PDGF), and insulin on DNA synthesis were studied in murine fibroblasts transfected with an expression vector containing human insulin receptor cDNA (NIH 3T3/HIR) and the parental NIH 3T3 cells. In NIH 3T3/HIR cells, individual growth factors in serum-free medium stimulated DNA synthesis with the following relative efficacies: insulin greater than or equal to 10% fetal calf serum greater than PDGF greater than IGF-1 much greater than EGF. In comparison, the relative efficacies of these factors in stimulating DNA synthesis by NIH 3T3 cells were 10% fetalmore » calf serum greater than PDGF greater than EGF much greater than IGF-1 = insulin. In NIH 3T3/HIR cells, EGF was synergistic with 1-10 ng/ml insulin but not with 100 ng/ml insulin or more. Synergy of PDGF or IGF-1 with insulin was not detected. In the parental NIH 3T3 cells, insulin and IGF-1 were found to be synergistic with EGF (1 ng/ml), PDGF (100 ng/ml), and PDGF plus EGF. In NIH 3T3/HIR cells, the lack of interaction of insulin with other growth factors was also observed when the percentage of cells synthesizing DNA was examined. Despite insulin's inducing only 60% of NIH 3T3/HIR cells to incorporate thymidine, addition of PDGF, EGF, or PDGF plus EGF had no further effect. In contrast, combinations of growth factors resulted in 95% of the parental NIH 3T3 cells synthesizing DNA. The independence of insulin-stimulated DNA synthesis from other mitogens in the NIH 3T3/HIR cells is atypical for progression factor-stimulated DNA synthesis and is thought to be partly the result of insulin receptor expression in an inappropriate context or quantity.« less

Insulin-like growth factors in embryonic and fetal growth and skeletal development (Review).

PubMed

Agrogiannis, Georgios D; Sifakis, Stavros; Patsouris, Efstratios S; Konstantinidou, Anastasia E

2014-08-01

The insulin-like growth factors (IGF)-I and -II have a predominant role in fetal growth and development. IGFs are involved in the proliferation, differentiation and apoptosis of fetal cells in vitro and the IGF serum concentration has been shown to be closely correlated with fetal growth and length. IGF transcripts and peptides have been detected in almost every fetal tissue from as early in development as pre‑implantation to the final maturation stage. Furthermore, IGFs have been demonstrated to be involved in limb morphogenesis. However, although ablation of Igf genes in mice resulted in growth retardation and delay in skeletal maturation, no impact on outgrowth and patterning of embryonic limbs was observed. Additionally, various molecular defects in the Igf1 and Igf1r genes in humans have been associated with severe intrauterine growth retardation and impaired skeletal maturation, but not with truncated limbs or severe skeletal dysplasia. The conflicting data between in vitro and in vivo observations with regard to bone morphogenesis suggests that IGFs may not be the sole trophic factors involved in fetal skeletal growth and that redundant mechanisms may exist in chondro- and osteogenesis. Further investigation is required in order to elucidate the functions of IGFs in skeletal development.

Sex-specific effect of endothelin in the blood pressure response to acute angiotensin II in growth-restricted rats

PubMed Central

Intapad, Suttira; Ojeda, Norma B.; Varney, Elliott; Royals, Thomas P.; Alexander, Barbara T.

2015-01-01

The renal endothelin system contributes to sex differences in blood pressure with males demonstrating greater endothelin type-A receptor-mediated responses relative to females. Intrauterine growth restriction programs hypertension and enhanced renal sensitivity to acute angiotensin II in male growth-restricted rats. Endothelin is reported to work synergistically with angiotensin II. Thus, this study tested the hypothesis that endothelin augments the blood pressure response to acute angiotensin II in male growth-restricted rats. Systemic and renal hemodynamics were determined in response to acute angiotensin II (100 nanogram/kilogram/minute for 30 minutes) with and without the endothelin type-A receptor antagonist, ABT 627(10 nanogram/kilogram/minute for 30 minutes), in rats pretreated with enalapril (250 milligram/Liter for one week) to normalize the endogenous renin angiotensin system. Endothelin type-A receptor blockade reduced angiotensin II-mediated increases in blood pressure in male control and male growth-restricted rats. Endothelin type-A receptor blockade also abolished hyper-responsiveness to acute angiotensin II in male growth-restricted rats. Yet, blood pressure remained significantly elevated above baseline following endothelin type-A receptor blockade suggesting that factors in addition to endothelin contribute to the basic angiotensin II-induced pressor response in male rats. We also determined sex-specific effects of endothelin on acute angiotensin II-mediated hemodynamic responses. Endothelin type-A receptor blockade did not reduce acute angiotensin II-mediated increases in blood pressure in female control or growth-restricted rats, intact or ovariectomized. Thus, these data suggest that endothelin type-A receptor blockade contributes to hypersensitivity to acute angiotensin II in male growth-restricted rats and further supports the sex-specific effect of endothelin on blood pressure. PMID:26459423

Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation.

PubMed

Gaviglio, Angela L; Knelson, Erik H; Blobe, Gerard C

2017-05-01

High-risk neuroblastoma is characterized by undifferentiated neuroblasts and low schwannian stroma content. The tumor stroma contributes to the suppression of tumor growth by releasing soluble factors that promote neuroblast differentiation. Here we identify heparin-binding epidermal growth factor-like growth factor (HBEGF) as a potent prodifferentiating factor in neuroblastoma. HBEGF mRNA expression is decreased in human neuroblastoma tumors compared with benign tumors, with loss correlating with decreased survival. HBEGF protein is expressed only in stromal compartments of human neuroblastoma specimens, with tissue from high-stage disease containing very little stroma or HBEGF expression. In 3 human neuroblastoma cell lines (SK-N-AS, SK-N-BE2, and SH-SY5Y), soluble HBEGF is sufficient to promote neuroblast differentiation and decrease proliferation. Heparan sulfate proteoglycans and heparin derivatives further enhance HBEGF-induced differentiation by forming a complex with the epidermal growth factor receptor, leading to activation of the ERK1/2 and STAT3 pathways and up-regulation of the inhibitor of DNA binding transcription factor. These data support a role for loss of HBEGF in the neuroblastoma tumor microenvironment in neuroblastoma pathogenesis.-Gaviglio, A. L., Knelson, E. H., Blobe, G. C. Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation. © FASEB.

Neurodevelopmental effects of insulin-like growth factor signaling

PubMed Central

O’Kusky, John; Ye, Ping

2012-01-01

Insulin-like growth factor (IGF) signaling greatly impacts the development and growth of the central nervous system (CNS). IGF-I and IGF-II, two ligands of the IGF system, exert a wide variety of actions both during development and in adulthood, promoting the survival and proliferation of neural cells. The IGFs also influence the growth and maturation of neural cells, augmenting dendritic growth and spine formation, axon outgrowth, synaptogenesis, and myelination. Specific IGF actions, however, likely depend on cell type, developmental stage, and local microenvironmental milieu within the brain. Emerging research also indicates that alterations in IGF signaling likely contribute to the pathogenesis of some neurological disorders. This review summarizes experimental studies and shed light on the critical roles of IGF signaling, as well as its mechanisms, during CNS development. PMID:22710100

Phase II trial of epidermal growth factor ointment for patients with Erlotinib-related skin effects.

PubMed

Hwang, In Gyu; Kang, Jung Hun; Oh, Sung Yong; Lee, Suee; Kim, Sung-Hyun; Song, Ki-Hoon; Son, Choonhee; Park, Min Jae; Kang, Myung Hee; Kim, Hoon Gu; Lee, Jeeyun; Park, Young Suk; Sun, Jong Mu; Kim, Hyun Jung; Kim, Chan Kyu; Yi, Seong Yoon; Jang, Joung-Soon; Park, Keunchil; Kim, Hyo-Jin

2016-01-01

The efficacy of erlotinib, the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, has been demonstrated in patients with non-small cell lung cancer (NSCLC) and pancreatic cancer (PC). In the present study, we evaluated the effect of epidermal growth factor (EGF) ointment on erlotinib-related skin effects (ERSEs). This was an open-label, non-comparative, multicenter, phase II trial. The patients included those diagnosed with NSCLC or PC who were treated with erlotinib. The effectiveness of the ointment was defined as follows: (1) grade 2, 3, or 4 ERSEs downgraded to ≤ grade 1 or (2) grade 3 or 4 ERSEs downgraded to grade 2 and persisted for at least 2 weeks. Fifty-two patients from seven institutes in Korea were enrolled with informed consent. The final assessment included 46 patients (30 males, 16 females). According to the definition of effectiveness, the EGF ointment was effective in 36 (69.2%) intention to treat patients. There were no statistically significant differences in the effectiveness of the EGF ointment by gender (p = 0.465), age (p = 0.547), tumor type (p = 0.085), erlotinib dosage (p = 0.117), and number of prior chemotherapy sessions (p = 0.547). The grading for the average National Cancer Institute's Common Terminology Criteria for Adverse Events (NCI-CTCAE) rating of rash/acne and itching improved from 2.02 ± 0.83 to 1.13 ± 0.89 and 1.52 ± 0.84 to 0.67 ± 0.90, respectively (p < 0.001). The most common reason for discontinuing the study was progression of cancer (37%). Based on the results, the EGF ointment is effective for ERSEs, regardless of gender, age, type of tumor, and dosage of erlotinib. The EGF ointment evenly improved all kinds of symptoms of ERSEs. ClinicalTrials.gov identifier: NCT01593995.

Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation

PubMed Central

Gaviglio, Angela L.; Knelson, Erik H.; Blobe, Gerard C.

2017-01-01

High-risk neuroblastoma is characterized by undifferentiated neuroblasts and low schwannian stroma content. The tumor stroma contributes to the suppression of tumor growth by releasing soluble factors that promote neuroblast differentiation. Here we identify heparin-binding epidermal growth factor–like growth factor (HBEGF) as a potent prodifferentiating factor in neuroblastoma. HBEGF mRNA expression is decreased in human neuroblastoma tumors compared with benign tumors, with loss correlating with decreased survival. HBEGF protein is expressed only in stromal compartments of human neuroblastoma specimens, with tissue from high-stage disease containing very little stroma or HBEGF expression. In 3 human neuroblastoma cell lines (SK-N-AS, SK-N-BE2, and SH-SY5Y), soluble HBEGF is sufficient to promote neuroblast differentiation and decrease proliferation. Heparan sulfate proteoglycans and heparin derivatives further enhance HBEGF-induced differentiation by forming a complex with the epidermal growth factor receptor, leading to activation of the ERK1/2 and STAT3 pathways and up-regulation of the inhibitor of DNA binding transcription factor. These data support a role for loss of HBEGF in the neuroblastoma tumor microenvironment in neuroblastoma pathogenesis.—Gaviglio, A. L., Knelson, E. H., Blobe, G. C. Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation. PMID:28174207

Clinical Evaluation of Insulin like Growth Factor-I and Vascular Endothelial Growth Factor with Alloplastic Bone Graft Material in the Management of Human Two Wall Intra-Osseous Defects

PubMed Central

Dixit, Jaya

2016-01-01

Introduction In recent years, emphasis on the use of growth factors for periodontal healing is gaining great momentum. Several growth factors showed promising results in periodontal regeneration. Aim This study was designed to compare the clinical outcomes of 0.8μg recombinant human Vascular Endothelial Growth Factor (rh-VEGF) and 10μg recombinant human Insulin Like Growth Factor-I (rh-IGF-I) with β-Tricalcium Phosphate (β-TCP) and Polylactide-Polyglycolide Acid (PLGA) membrane in two wall intra-osseous defects. Materials and Methods A total of 29 intra-osseous defects in 27 subjects were randomly divided into 3 test and 1 control group. Test group I (n=8) received rh-VEGF+ rh-IGF-I, Test group II (n=7) rh-VEGF, Test group III (n=7) rh-IGF-I and control group (n=7) with no growth factor, β-TCP and PLGA membrane was used in all the groups. Baseline soft tissue parameters including Probing Pocket Depth (PPD), Clinical Attachment Level (CAL), and Gingival Recession (GR) at selected sites were recorded at baseline and at 6 months. Intrasurgically, intra-osseous component was calculated as a) Cemento-Enamel Junction to Bone Crest (CEJ to BC), b) Bone Crest to Base of the Defect (BC to BD) at baseline and at re-entry. The mean changes at baseline and after 6 months within each group were compared using Wilcoxon Signed Rank Test. The mean changes for each parameter between groups were compared using Mann-Whitney U test. Results After 6 months, maximum mean PPD reduction occurred in test group I followed by test group II, III and control group. Similar trend was observed in CAL gain. Non-significant GR was present in test group I and control group whereas in test group II and III GR was absent. The use of rh-VEGF+ rhIGF-I exhibited 95.8% osseous fill as compared to 54.8% in test group II, 52.7% in test group III and 41.1 % in the control group. Conclusion Within the limitations of this study, it can be concluded that, rh-IGF-I+rh-VEGF treated sites resulted in greater

Hypoglycemia in a dog with a leiomyoma of the gastric wall producing an insulin-like growth factor II-like peptide.

PubMed

Boari, A; Barreca, A; Bestetti, G E; Minuto, F; Venturoli, M

1995-06-01

A 12-year-old mixed-breed male dog was referred to the Clinica Medica Veterinaria of Bologna University for recurrent episodes of seizures due to hypoglycemia with abnormally low plasma insulin levels (18 pmol/l). Resection of a large leiomyoma (780 g) of the gastric wall resulted in a permanent resolution of the hypoglycemic episodes. Insulin-like growth factors I and II (IGF-I and -II) were measured by RIA in serum before and after surgery and in tumor tissue. Results were compared to the serum concentration of 54 normal and to the tissue concentration observed in eight non-hypoglycemic dog gastric wall extracts. Before surgery, circulating immunoreactive IGF-I was 0.92 nmol/l, which is significantly lower than the control values (16.92 +/- 8.44 nmol/l, range 3.53-35.03), while IGF-II was 152 nmol/l, which is significantly higher than the control values (42.21 +/- 3.75, range 31.99-50.74). After surgery, IGF-I increased to 6.80 nmol/l while IGF-II decreased to 45.52 nmol/l. Tumor tissue IGF-II concentration was higher than normal (5.66 nmol/kg tissue as compared to a range in normal gastric wall tissue of 1.14-3.72 nmol/kg), while IGF-I was 0.08 nmol/kg tissue, which is close to the lowest normal value (range in controls, 0.08-1.18 nmol/kg). Partial characterization of IGF-II immunoreactivity extracted from tissue evidenced a molecular weight similar to that of mature IGF-II, thus excluding that peptide released by the tumor is a precursor molecule.(ABSTRACT TRUNCATED AT 250 WORDS)

Insulin-Like Growth Factors and Metabolic Syndrome in Obese Children.

PubMed

Inzaghi, Elena; Baldini Ferroli, Barbara; Fintini, Danilo; Grossi, Armando; Nobili, Valerio; Cianfarani, Stefano

2017-01-01

Insulin-like growth factor (IGF)-I is related to cardiometabolic risk in adults, whereas the metabolic role of IGF-II is unclear. The aim of this study was to assess IGFs in obese children and correlate them with metabolic syndrome (MetS) components. This is a retrospective study including 574 obese children (11.34 ± 3.16 years). All subjects underwent complete anthropometry and biochemical assessment. In a subgroup of 136 subjects, body composition was evaluated. IGF-I was measured in 300 obese subjects and IGF-II in 77 obese and 15 lean children. 177 subjects were divided according to the presence of 1 or more MetS criteria: group 1, subjects with 1 MetS criterion; group 2, subjects with 2 components; and group 3, subjects with MetS diagnosis. IGF-I, IGF-II, and IGF-I/insulin-like growth factor-binding protein-3 ratio were not different among subjects with an increasing number of MetS criteria and were not associated with single components of MetS as well as with body composition parameters. In children younger than 10 years, IGF-I directly correlated with high-density lipoprotein cholesterol (p < 0.005) even after controlling for confounders. IGF-II was significantly higher in obese children and correlated with parameters of insulin sensitivity (p < 0.05). IGFs were neither related to MetS nor to body composition parameters in obese children. Further studies are needed to clarify the mechanisms underlying the relationship between IGF-II and insulin sensitivity. © 2017 S. Karger AG, Basel.

Reliability of Growth Indicators and Efficiency of Functional Treatment for Skeletal Class II Malocclusion: Current Evidence and Controversies.

PubMed

Perinetti, Giuseppe; Contardo, Luca

2017-01-01

Current evidence on the reliability of growth indicators in the identification of the pubertal growth spurt and efficiency of functional treatment for skeletal Class II malocclusion, the timing of which relies on such indicators, is highly controversial. Regarding growth indicators, the hand and wrist (including the sole middle phalanx of the third finger) maturation method and the standing height recording appear to be most reliable. Other methods are subjected to controversies or were showed to be unreliable. Main sources of controversies include use of single stages instead of ossification events and diagnostic reliability conjecturally based on correlation analyses. Regarding evidence on the efficiency of functional treatment, when treated during the pubertal growth spurt, more favorable response is seen in skeletal Class II patients even though large individual responsiveness remains. Main sources of controversies include design of clinical trials, definition of Class II malocclusion, and lack of inclusion of skeletal maturity among the prognostic factors. While no growth indicator may be considered to have a full diagnostic reliability in the identification of the pubertal growth spurt, their use may still be recommended for increasing efficiency of functional treatment for skeletal Class II malocclusion.

Reliability of Growth Indicators and Efficiency of Functional Treatment for Skeletal Class II Malocclusion: Current Evidence and Controversies

PubMed Central

2017-01-01

Current evidence on the reliability of growth indicators in the identification of the pubertal growth spurt and efficiency of functional treatment for skeletal Class II malocclusion, the timing of which relies on such indicators, is highly controversial. Regarding growth indicators, the hand and wrist (including the sole middle phalanx of the third finger) maturation method and the standing height recording appear to be most reliable. Other methods are subjected to controversies or were showed to be unreliable. Main sources of controversies include use of single stages instead of ossification events and diagnostic reliability conjecturally based on correlation analyses. Regarding evidence on the efficiency of functional treatment, when treated during the pubertal growth spurt, more favorable response is seen in skeletal Class II patients even though large individual responsiveness remains. Main sources of controversies include design of clinical trials, definition of Class II malocclusion, and lack of inclusion of skeletal maturity among the prognostic factors. While no growth indicator may be considered to have a full diagnostic reliability in the identification of the pubertal growth spurt, their use may still be recommended for increasing efficiency of functional treatment for skeletal Class II malocclusion. PMID:28168195

The growth hormone-insulin-like growth factor axis in glycogen storage disease type 1: evidence of different growth patterns and insulin-like growth factor levels in patients with glycogen storage disease type 1a and 1b.

PubMed

Melis, Daniela; Pivonello, Rosario; Parenti, Giancarlo; Della Casa, Roberto; Salerno, Mariacarolina; Balivo, Francesca; Piccolo, Pasquale; Di Somma, Carolina; Colao, Annamaria; Andria, Generoso

2010-04-01

To investigate the growth hormone (GH)-insulin-like growth factor (IGF) system in patients with glycogen storage disease type 1 (GSD1). This was a prospective, case-control study. Ten patients with GSD1a and 7 patients with GSD1b who were given dietary treatment and 34 sex-, age-, body mass index-, and pubertal stage-matched control subjects entered the study. Auxological parameters were correlated with circulating GH, either at basal or after growth hormone releasing hormone plus arginine test, insulin-like growth factors (IGF-I and IGF-II), and anti-pituitary antibodies (APA). Short stature was detected in 10.0% of patients with GSD1a, 42.9% of patients with GSD1b (P = .02), and none of the control subjects. Serum IGF-I levels were lower in patients with GSD1b (P = .0001). An impaired GH secretion was found in 40% of patients with GSD1a (P = .008), 57.1% of patients with GSD1b (P = .006), and none of the control subjects. Short stature was demonstrated in 3 of 4 patients with GSD1b and GH deficiency. The prevalence of APA was significantly higher in patients with GSD1b than in patients with GSD1a (P = .02) and control subjects (P = .03). The GH response to the provocative test inversely correlated with the presence of APA (P = .003). Compared with levels in control subjects, serum IGF-II and insulin levels were higher in both groups of patients, in whom IGF-II levels directly correlated with height SD scores (P = .003). Patients with GSD1a have an impaired GH secretion associated with reference range serum IGF-I levels and normal stature, whereas in patients with GSD1b, the impaired GH secretion, probably because of the presence of APA, was associated with reduced IGF-I levels and increased prevalence of short stature. The increased IGF-II levels, probably caused by increased insulin levels, in patients with GSD1 are presumably responsible for the improved growth pattern observed in patients receiving strict dietary treatment. Copyright 2010 Mosby, Inc. All

Growth factors and cytokines in patients with long bone fractures and associated spinal cord injury.

PubMed

Khallaf, Fathy G; Kehinde, Elijah O; Mostafa, Ahmed

2016-06-01

The aim of the study was to test the effect of acute traumatic spinal cord injury of quadriplegia or paraplegia on bone healing in patients with associated long bone fractures and to investigate the molecular and cellular events of the underlying mechanism for a possible acceleration. Healing indicators of long bone fractures and growth factors, IGF-II, platelet-derived growth factor (PDGF), vascular endothelial growth factor (VEGF), Activin-A, and cytokine I-L-1, in the patients' blood were calculated and measured for 21 patients with spinal cord injuries and associated long bone fractures in prospective controlled study and compared to 20 patients with only spinal cord injuries, 30 patients with only long bone fractures, and 30 healthy volunteers. The study results showed that long bone fractures in patients with associated acute traumatic spinal cord injury of quadriplegia or paraplegia heal more expectedly, faster, and with exuberant florid union callus (P > 0.001) and show statistically significant higher levels of growth factors like PDGF, VEGF, Activin-A, and cytokine I-L-1, along the 3 weeks of follow-up (P > 0.005). I-IGF-II showed statistically significant subnormal level along the whole follow-up period in the same patients (P > 0.005). We concluded that long bone fractures in spinal cord injury patients heal more expectedly, faster, and with exuberant and florid callus formation; growth factors like IGF-II, PDGF, VEGF, Activin-A, and cytokine I-L-I have roles as mediators, in molecular events and as byproducts of the subtle mechanism of accelerated osteogenesis in these patients and may represent therapeutic potentials to serve as agents to enhance bone repair.

Improving In Vitro Generated Cartilage-Carrier-Constructs by Optimizing Growth Factor Combination

PubMed Central

Wiegandt, Katharina; Goepfert, Christiane; Pörtner, Ralf

2007-01-01

The presented study is focused on the generation of osteochondral implants for cartilage repair, which consist of bone substitutes covered with in vitro engineered cartilage. Re-differentiation of expanded porcine cells was performed in alginate gel followed by cartilage formation in high-density cell cultures. In this work, different combinations of growth factors for the stimulation of re-differentiation and cartilage formation have been tested to improve the quality of osteochondral implants. It has been demonstrated that supplementation of the medium with growth factors has significant effects on the properties of the matrix. The addition of the growth factors IGF-I (100 ng/mL) and TGF-β1 (10 ng/mL) during the alginate culture and the absence of any growth factors during the high-density cell culture led to significantly higher GAG to DNA ratios and Young’s Moduli of the constructs compared to other combinations. The histological sections showed homogenous tissue and intensive staining for collagen type II. PMID:19662133

Angiotensin II Receptor Antagonism Reduces Transforming Growth Factor Beta and Smad Signaling in Thoracic Aortic Aneurysm

PubMed Central

Nataatmadja, Maria; West, Jennifer; Prabowo, Sulistiana; West, Malcolm

2013-01-01

ABSTRACT Background The expression of transforming growth factor beta (TGF-β) and Smad3 regulates extracellular matrix homeostasis and inflammation in aortic aneurysms. The expression of Smad3 depends on signaling by angiotensin II (AngII) receptor pathways through TGF-β receptor–dependent and –independent pathways. Methods To determine the expression of AngII type 1 (AT1R) and type 2 receptors (AT2R), TGF-β, and Smad3 in thoracic aortic aneurysms, we performed immunohistochemistry testing on tissue and cultured cells derived from subjects with Marfan syndrome (MFS) and bicuspid aortic valve (BAV) malformation and from normal aortas of subjects who were organ donors. Results MFS and BAV aneurysm tissue showed enhanced accumulation of TGF-β and Smad3 in vascular smooth muscle cells (VSMCs) and in inflammatory cells in the subintimal layer and tunica media. The normal aortic wall exhibited minimal TGF-β and Smad3 staining. Cultured VSMCs from MFS and BAV samples showed nuclear Smad3 and strong cytoplasmic TGF-β expression in the cytoplasmic vesicles. In control cells, Smad3 was located mainly in the cytoplasm, and weak cytoplasmic TGF-β was distributed with a pattern similar to that of the aneurysm-derived cells. Compared to normal aorta cells, AT1R and AT2R expression was increased in both aneurysm types. Treatment of cultured VSMCs with the AT1R antagonist losartan caused both reduced TGF-β vesicle localization and nuclear expression of Smad3. Conclusions Increased TGF-β and Smad3 expression in aneurysm tissue and cultured VSMCs is consistent with aberrant TGF-β expression and the activation of Smad3 signaling. Losartan-mediated reduction in TGF-β expression and the cytoplasmic localization of Smad3 support a role for AT1R antagonism in the inhibition of aneurysm progression. PMID:23532685

Intracellular signaling pathways required for rat vascular smooth muscle cell migration. Interactions between basic fibroblast growth factor and platelet-derived growth factor.

PubMed Central

Bilato, C; Pauly, R R; Melillo, G; Monticone, R; Gorelick-Feldman, D; Gluzband, Y A; Sollott, S J; Ziman, B; Lakatta, E G; Crow, M T

1995-01-01

Intracellular signaling pathways activated by both PDGF and basic fibroblast growth factor (bFGF) have been implicated in the migration of vascular smooth muscle cells (VSMC), a key step in the pathogenesis of many vascular diseases. We demonstrate here that, while bFGF is a weak chemoattractant for VSMCs, it is required for the PDGF-directed migration of VSMCs and the activation of calcium/calmodulin-dependent protein kinase II (CamKinase II), an intracellular event that we have previously shown to be important in the regulation of VSMC migration. Neutralizing antibodies to bFGF caused a dramatic reduction in the size of the intracellular calcium transient normally seen after PDGF stimulation and inhibited both PDGF-directed VSMC migration and CamKinase II activation. Partially restoring the calcium transient with ionomycin restored migration and CamKinase II activation as did the forced expression of a mutant CamKinase II that had been "locked" in the active state by site-directed mutagenesis. These results suggest that bFGF links PDGF receptor stimulation to changes in intracellular calcium and CamKinase II activation, reinforcing the central role played by CamKinase II in regulating VSMC migration. Images PMID:7560082

Activity of insulin growth factors and shrimp neurosecretory organ extracts on a lepidopteran cell line.

PubMed

Hatt, P J; Liebon, C; Morinière, M; Oberlander, H; Porcheron, P

1997-01-01

Ecdysteroids, or molting hormones, have been proven to be key differentiation regulators for epidermal cells in the postembryonic development of arthropods. Regulators of cell proliferation, however, remain largely unknown. To date, no diffusible insect peptidic growth factors have been characterized. Molecules structurally related to insulin have been discovered in insects, as in other eucaryotes. We developed in vitro tests for the preliminary characterization of potential growth factors in arthropods by adapting the procedures designed to detect such factors in vertebrates to an insect cell line (IAL-PID2) established from imaginal discs of the Indian meal moth. We verified the ability of these tests to measure the proliferation of IAL-PID2 cells. We tested mammalian insulin and insulin-like growth factors (IGF-I, IGF-II). Following an arrest of cell proliferation by serum deprivation, IGF-I and IGF-II caused partial resumption of the cell cycle, evidenced by DNA synthesis. In contrast, the addition of 20-hydroxyecdysone arrested the proliferation of the IAL-PID2 cells. The cell line was then used in a test for functional characterization of potential growth factors originating from the penaeid shrimp, Penaeus vannamei. Crude extracts of neurosecretory and nervous tissues, eyestalks, and ventral neural chain compensated for serum deprivation and stimulated completion of mitosis. Arch.

Skeletal muscle hypertrophy and regeneration: interplay between the myogenic regulatory factors (MRFs) and insulin-like growth factors (IGFs) pathways.

PubMed

Zanou, Nadège; Gailly, Philippe

2013-11-01

Adult skeletal muscle can regenerate in response to muscle damage. This ability is conferred by the presence of myogenic stem cells called satellite cells. In response to stimuli such as injury or exercise, these cells become activated and express myogenic regulatory factors (MRFs), i.e., transcription factors of the myogenic lineage including Myf5, MyoD, myogenin, and Mrf4 to proliferate and differentiate into myofibers. The MRF family of proteins controls the transcription of important muscle-specific proteins such as myosin heavy chain and muscle creatine kinase. Different growth factors are secreted during muscle repair among which insulin-like growth factors (IGFs) are the only ones that promote both muscle cell proliferation and differentiation and that play a key role in muscle regeneration and hypertrophy. Different isoforms of IGFs are expressed during muscle repair: IGF-IEa, IGF-IEb, or IGF-IEc (also known as mechano growth factor, MGF) and IGF-II. MGF is expressed first and is observed in satellite cells and in proliferating myoblasts whereas IGF-Ia and IGF-II expression occurs at the state of muscle fiber formation. Interestingly, several studies report the induction of MRFs in response to IGFs stimulation. Inversely, IGFs expression may also be regulated by MRFs. Various mechanisms are proposed to support these interactions. In this review, we describe the general process of muscle hypertrophy and regeneration and decipher the interactions between the two groups of factors involved in the process.

Red blood cells release factors with growth and survival bioactivities for normal and leukemic T cells.

PubMed

Antunes, Ricardo F; Brandão, Cláudia; Maia, Margarida; Arosa, Fernando A

2011-01-01

Human red blood cells are emerging as a cell type capable to regulate biological processes of neighboring cells. Hereby, we show that human red blood cell conditioned media contains bioactive factors that favor proliferation of normal activated T cells and leukemic Jurkat T cells, and therefore called erythrocyte-derived growth and survival factors. Flow cytometry and electron microscopy in parallel with bioactivity assays revealed that the erythrocyte factors are present in the vesicle-free supernatant, which contains up to 20 different proteins. The erythrocyte factors are thermosensitive and do not contain lipids. Native polyacrylamide gel electrophoresis followed by passive elution and mass spectrometry identification reduced the potential erythrocyte factors to hemoglobin and peroxiredoxin II. Two-dimensional differential gel electrophoresis of the erythrocyte factors revealed the presence of multiple hemoglobin oxy-deoxy states and peroxiredoxin II isoforms differing in their isoelectric point akin to the presence of β-globin chains. Our results show that red blood cells release protein factors with the capacity to sustain T-cell growth and survival. These factors may have an unforeseen role in sustaining malignant cell growth and survival in vivo.

UAP56 is an important mediator of Angiotensin II/platelet derived growth factor induced vascular smooth muscle cell DNA synthesis and proliferation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sahni, Abha; Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555; Wang, Nadan

2013-02-15

Highlights: ► Knockdown of UAP56 inhibits Angiotensin II/PDGF induced vascular smooth muscle cell proliferation. ► UAP56 is a positive regulator of E2F transcriptional activation. ► UAP56 is present in the vessel wall of low flow carotid arteries. -- Abstract: Angiotensin (Ang) II and platelet-derived growth factor (PDGF) are important mediators of pathologic vascular smooth muscle cell (VSMC) proliferation. Identifying downstream mediators of Ang II and PDGF signaling may provide insights for therapies to improve vascular proliferative diseases. We have previously demonstrated that breakpoint cluster region (Bcr) is an important mediator of Ang II/PDGF signaling in VSMC. We have recently reportedmore » that the DExD/H box protein UAP56 is an interacting partner of Bcr in regulating VSMC DNA synthesis. We hypothesized that UAP56 itself is an important regulator of VSMC proliferation. In this report we demonstrate that knockdown of UAP56 inhibits Ang II/PDGF induced VSMC DNA synthesis and proliferation, and inhibits E2F transcriptional activity. In addition, we demonstrate that UAP56 is present in the vessel wall of low-flow carotid arteries. These findings suggest that UAP56 is a regulator of VSMC proliferation and identify UAP56 as a target for preventing vascular proliferative disease.« less

Combinatorial compatibility as habit-controlling factor in lysozyme crystallization II. Morphological evidence for tetrameric growth units

NASA Astrophysics Data System (ADS)

Strom, C. S.; Bennema, P.

1997-03-01

This work (Part II) explores the relation between units and morphology. It shows the equivalence in behaviour between the attachment energies and the results of Monte Carlo growth kinetics simulations. The energetically optimal combination of the F slices in 1 1 0, 0 1 1 and 1 1 1 in a monomolecular interpretation leads to unsatisfactory agreement with experimentally observed morphology. In a tetrameric (or octameric) interpretation, the unit cell must be subdivided self-consistently in terms of stable molecular clusters. Thus, the presence or absence of the 1 1 1 form functions as a direct experimental criterion for distinguishing between monomolecular growth layers, and tetrameric (or octameric) growth layers of the same composition, but subjected to the condition of combinatorial compatibility, as the F slices combine to produce the growth habit. When that condition is taken into account, the tetrameric (or octameric) theoretical morphology in the broken bond model is in good agreement with experiment over a wide range. Subjectmatter for future study is summarized.

The chemokine CXCL12 mediates the anti-amyloidogenic action of painless human nerve growth factor.

PubMed

Capsoni, Simona; Malerba, Francesca; Carucci, Nicola Maria; Rizzi, Caterina; Criscuolo, Chiara; Origlia, Nicola; Calvello, Mariantonietta; Viegi, Alessandro; Meli, Giovanni; Cattaneo, Antonino

2017-01-01

Nerve growth factor is a therapeutic candidate for Alzheimer's disease. Due to its pain-inducing activity, in current clinical trials nerve growth factor is delivered locally into the brain by neurosurgery, but data on the efficacy of local nerve growth factor delivery in decreasing amyloid-β deposition are not available. To reduce the nerve growth factor pain-inducing side effects, thus avoiding the need for local brain injection, we developed human painless nerve growth factor (hNGFp), inspired by the human genetic disease hereditary sensory and autonomic neuropathy type V. hNGFp has identical neurotrophic potency as wild-type human nerve growth factor, but a 10-fold lower pain sensitizing activity. In this study we first mimicked, in the 5xFAD mouse model, the intraparenchymal delivery of hNGFp used in clinical trials and found it to be ineffective in decreasing amyloid-β plaque load. On the contrary, the same dose of hNGFp delivered intranasally, which was widely biodistributed in the brain and did not induce pain, showed a potent anti-amyloidogenic action and rescued synaptic plasticity and memory deficits. We found that hNGFp acts on glial cells, modulating inflammatory proteins such as the soluble TNFα receptor II and the chemokine CXCL12. We further established that the rescuing effect by hNGFp is mediated by CXCL12, as pharmacological inhibition of CXCL12 receptor CXCR4 occludes most of hNGFp effects. These findings have significant therapeutic implications: (i) we established that a widespread exposure of the brain is required for nerve growth factor to fully exert its neuroprotective actions; and (ii) we have identified a new anti-neurodegenerative pathway as a broad target for new therapeutic opportunities for neurodegenerative diseases. © The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain.

Factor II assay

MedlinePlus

... this page: //medlineplus.gov/ency/article/003674.htm Factor II assay To use the sharing features on ... M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health ...

40 CFR Table II-1 to Subpart II of... - Emission Factors

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Emission Factors II Table II-1 to Subpart II of Part 98 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Industrial Wastewater Treatment Pt. 98, Subpt. II, Table II-1...

40 CFR Table II-1 to Subpart II of... - Emission Factors

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 22 2013-07-01 2013-07-01 false Emission Factors II Table II-1 to Subpart II of Part 98 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Industrial Wastewater Treatment Pt. 98, Subpt. II, Table II-1...

Evidence for growth hormone/insulin-like growth factor I axis regulation of seawater acclimation in the euryhaline teleost Fundulus heteroclitus

USGS Publications Warehouse

Mancera, J.M.; McCormick, S.D.

1998-01-01

The ability of ovine growth hormone (oGH), recombinant bovine insulin- like growth factor I (rbIGF-I), recombinant human insulin-like growth factor II (rhIGF-II), and bovine insulin to increase hypoosmoregulatory capacity in the euryhaline teleost Fundulus heteroclitus was examined. Fish acclimated to brackish water (BW, 10 ppt salinity, 320 mOsm/kg H2O) were injected with a single dose of hormone and transferred to seawater (SW, 35 ppt salinity, 1120 mOsm/kg H2O) 2 days later. Fish were sampled 24 h after transfer and plasma osmolality, plasma glucose, and gill Na+,K+-ATPase activity were examined. Transfer from BW to SW increased plasma osmolality and gill Na+,K+-ATPase activity. Transfer from BW to BW had no effect on these parameters. rbIGF-I (0.05, 0.1, and 0.2 ??g/g) improved the ability to maintain plasma osmolality and to increase gill Na+, K+-ATPase activity in a dose-dependent manner. oGH (0.5, 1, and 2 ??g/g) also increased hypoosmoregulatory ability but only the higher doses (2 ??g/g) significantly increased gill Na+,K+-ATPase activity. oGH (1 ??g/g) and rbIGF-I (0.1 ??g/g) had a significantly greater effect on plasma osmolality and gill Na+,K+-ATPase activity than either hormone alone. rhIGF-II (0.05, 0.1, and 0.2 ??g/g) and bovine insulin (0.01 and 0.05 ??g/g) were without effect. The results suggest a role of GH and insulin-like growth factor I (IGF-I) in seawater acclimation of E heteroclitus. Based on these findings and previous studies, it is concluded that the capacity of the GH/IGF-I axis to increase hypoosmoregulatory ability may be a common feature of euryhalinity in teleosts.

Genetic polymorphisms of the IGF-II gene intron 8 coding region and its association with growth and carcass traits in yak.

PubMed

Zeng, Y F; Ding, X Z; Cheng, S R; Yu, S J

2013-12-11

Insulin-like growth factor II (IGF-II) plays a key role in mammalian growth and is involved in stimulating fetal cell division, differentiation, and metabolic regulation. IGF-II is considered a candidate gene for genetic markers of growth and carcass traits. Therefore, in this study, the associations of single nucleotide polymorphisms (SNPs) in the IGF-II gene region with growth and carcass characteristics in five yak breeds were investigated. Two SNPs, G(330)C and A(358)G, were identified by sequencing intron 8 of the IGF-II gene in homozygotes. Two alleles, A and B, and three genotypes, AA, AB, and BB, were identified by polymerase chain reaction. Genotypic frequencies of IGF-II allele B were 0.8623, 0.8936, 0.8535, 0.8676, and 0.8300 for Datong yak, Gannan yak, Tianzhu white yak, Qinghai Plateau yak, and Xinjiang yak, respectively. Allele and the genotype of IGF-II were strongly associated with growth and carcass traits. Least square analysis revealed a significant effect (P < 0.01) of genotypes AA and AB compared with genotype BB on live-weight (at 12, 13-24, and 25-36 months of age), average daily weight gain (P < 0.01) and carcass weight (P < 0.05). Animals with genotype AB had a higher mean rib eye area, and a lower mean yield grade. The results indicated that the IGF-II gene acts by a primarily additive biological mechanism by adding weight independently of skeletal growth.

Vascular endothelial growth factor and platelet-derived growth factor are potential angiogenic and metastatic factors in human breast cancer.

PubMed

Anan, K; Morisaki, T; Katano, M; Ikubo, A; Kitsuki, H; Uchiyama, A; Kuroki, S; Tanaka, M; Torisu, M

1996-03-01

Angiogenesis is a prerequisite for tumor growth and metastasis. Tumor angiogenesis may be mediated by several angiogenic factors such as vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), transforming growth factor-alpha, and basic fibroblast growth factor. Differential mRNA expressions of VEGF, PDGF (A chain), transforming growth factor-alpha and basic fibroblast growth factor in 32 primary invasive breast tumors were examined by reverse transcriptase-polymerase chain reaction. We analyzed relationships between mRNA expressions of these angiogenic factors and the degree of angiogenesis, tumor size, and metastasis. Quantification of angiogenesis was achieved by the immunohistochemical staining of endothelial cells with antibody to CD31. VEGF and PDGF-A mRNAs were expressed more frequently in breast tumors than in nontumor breast tissues, whereas no difference was found in expression frequency of either transforming growth factor-alpha or basic fibroblast growth factor mRNA. Vascular counts in tumors correlated with each expression frequency of VEGF and PDGF-A mRNA. PDGF-A mRNA was expressed more frequently in tumors with lymph node metastasis than in those without metastasis. Expression of VEGF and PDGF mRNAs detected by reverse transcriptase-polymerase chain reaction in breast tumors correlates with tumor-related characteristics of angiogenesis and metastatic potential. Analysis of these mRNAs by reverse transcriptase-polymerase chain reaction may be useful for assessing the biologic behavior of a breast tumor before surgical treatment.

Vapour phase growth and characterization of II-VI mixed crystals

NASA Astrophysics Data System (ADS)

Reddy, D. R.; Reddy, B. K.

1992-02-01

All II-VI semiconductors with melting temperatures well above 1000 degree(s)C and with appreciable congruent vaporization well below their melting temperatures leave little scope for any growth technique except for the slow but efficient vaporphase growth method. Theoretical flaw in diffusion models of vapor phase growth was corrected by Factor and Garrett by incorporating the flow velocity term which otherwise would lead to segregation of constituents. An additional degree of freedom arising from the presence of two components was well utilized to finely control the stoichiometry in binaries. In mixed II-VI systems the components are either three or four, depending on whether the system is a ternary or a quaternary. The added degrees of freedom make it very difficult to control stoichiometry. However, Igaki et al. demonstrated the feasibility of control of stoichiometry in CdSxSe1-x. In this paper, a self-sealing vaporphase growth technique used for both ternary and quaternary system is described. The systems studied are CdSxSe1-x, (ZnSe)x(CdTe)1-x and (ZnTe)x(CdSe)1-x. Results on growth mechanism, miscibility, structure, band gap variation, conductivity type variation with 'x' and transport properties are presented in a comparative way and discussed. CdSxSe1-x system in the entire 'X' has the same crystal structure and type of conductivity. The second system has the same zincblend structure but the type of conductivity is very sensitive to thermal treatment. In the last system both structure and types of conductivity are different. The discontinuities in properties associated with this divergent end compound are presented and discussed. Among the physical properties/parameters studied crystal structure, bandgap and nature of conductivity are tailorable, and magnitudes of conductivity and dielectric properties are very difficult to control in the crystals grown by this vapor phase method.

Expression of serum insulin-like growth factors, insulin-like growth factor-binding proteins, and the growth hormone-binding protein in heterozygote relatives of Ecuadorian growth hormone receptor deficient patients.

PubMed

Fielder, P J; Guevara-Aguirre, J; Rosenbloom, A L; Carlsson, L; Hintz, R L; Rosenfeld, R G

1992-04-01

Recently, an isolated population of apparent GH-receptor deficient (GHRD) patients has been identified in the Loja province of southern Ecuador. These individuals presented many of the physical and biochemical phenotypes characteristic of Laron-Syndrome and are believed to have a defect in the GH-receptor gene. In this study, we have compared the biochemical phenotypes between the affected individuals and their parents, considered to be obligate heterozygotes for the disorder. Serum GH, insulin-like growth factor I and II (IGF-I and IGF-II) levels were measured by RIA Insulin-like growth factor binding proteins. (IGFBPs) were measured by Western ligand blotting (WLB) of serum samples, following separation by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and relative quantitation of serum IGFBPs was performed with a scanning laser densitometer. Serum GH-binding protein (GHBP) levels were measured with a ligand-mediated immunofunctional assay using a monoclonal antibody raised against the GHBP. These values were then compared to values obtained from normal, sex-matched adult Ecuadorian controls, to determine if the above parameters were abnormal in the heterozygotes. The serum IGF-I levels of the GHRD patients were less than 13% of control values for adults and 2% for children. However, the IGF-I levels of both the mothers and fathers were not significantly different from that of the control population. The serum IGF-II levels of the GHRD patients were approximately 20% of control values for adults and 12% for the children. The IGF-II levels of the mothers were reduced, but were not significantly different from that of the control population. However, IGF-II levels of the fathers were significantly lower than those of controls (64% of control male levels). WLB analysis of serum IGFBP levels of the affected subjects demonstrated increased IGFBP-2 and decreased IGFBP-3, suggesting an inverse relationship between these IGFBPs. The GHRD patients who had the

Clinical Comparison of Autogenous Bone Graft with and without Plasma Rich in Growth Factors in the Treatment of Grade II Furcation Involvement of Mandibular Molars

PubMed Central

Lafzi, Ardeshir; Shirmohammadi, Adileh; Faramarzi, Masoumeh; Jabali, Sahar; Shayan, Arman

2013-01-01

Background and aims Plasma rich in growth factors (PRGF) is a concentrated suspension of growth factors, which is used to promote periodontal tissue regeneration. The aim of this randomized, controlled, clinical trial was to evaluate of the treatment of grade II mandibular molar furcation involvement using autogenous bone graft with and without PRGF. Materials and methods In this double-blind clinical trial, thirty mandibular molars with grade II furcation involvement in 30 patients were selected. The test group received bone graft combined with PRGF, while the control group was treated with bone graft only. Clinical parameters included clinical probing depth (CPD), vertical clinical attachment level (V-CAL), horizontal clinical attachment level (H-CAL), location of gingival margin (LGM), surgically exposed horizontal probing depth of bony defect (E-HPD), vertical depth of bone crest (V-DBC), vertical depth of the base of bony defect (V-DBD), and length of the intrabony defect (LID). After six months, a re-entry surgery was performed. Data were analyzed by SPSS 14, using Kolmogorov, Mann-Whitney U, and paired t-test. Results After 6 months, both treatment methods led to significant improvement in V-CAL and H-CAL and significant decreases in CPD, E-HPD, V-DBD and LID; there was no significant difference in LGM and V-DBC in any of the treated groups compared to the baseline values. Also, none of the parameters showed significant differences between the study groups. Conclusion Although autogenous bone grafts, with or without PRGF, were successful in treating grade II furcation involvement, no differences between the study groups were observed. PMID:23486928

Determination of the exact molecular requirements for type 1 angiotensin receptor epidermal growth factor receptor transactivation and cardiomyocyte hypertrophy.

PubMed

Smith, Nicola J; Chan, Hsiu-Wen; Qian, Hongwei; Bourne, Allison M; Hannan, Katherine M; Warner, Fiona J; Ritchie, Rebecca H; Pearson, Richard B; Hannan, Ross D; Thomas, Walter G

2011-05-01

Major interest surrounds how angiotensin II triggers cardiac hypertrophy via epidermal growth factor receptor transactivation. G protein-mediated transduction, angiotensin type 1 receptor phosphorylation at tyrosine 319, and β-arrestin-dependent scaffolding have been suggested, yet the mechanism remains controversial. We examined these pathways in the most reductionist model of cardiomyocyte growth, neonatal ventricular cardiomyocytes. Analysis with [(32)P]-labeled cardiomyocytes, wild-type and [Y319A] angiotensin type 1 receptor immunoprecipitation and phosphorimaging, phosphopeptide analysis, and antiphosphotyrosine blotting provided no evidence for tyrosine phosphorylation at Y319 or indeed of the receptor, and mutation of Y319 (to A/F) did not prevent either epidermal growth factor receptor transactivation in COS-7 cells or cardiomyocyte hypertrophy. Instead, we demonstrate that transactivation and cardiomyocyte hypertrophy are completely abrogated by loss of G-protein coupling, whereas a constitutively active angiotensin type 1 receptor mutant was sufficient to trigger transactivation and growth in the absence of ligand. These results were supported by the failure of the β-arrestin-biased ligand SII angiotensin II to transactivate epidermal growth factor receptor or promote hypertrophy, whereas a β-arrestin-uncoupled receptor retained these properties. We also found angiotensin II-mediated cardiomyocyte hypertrophy to be attenuated by a disintegrin and metalloprotease inhibition. Thus, G-protein coupling, and not Y319 phosphorylation or β-arrestin scaffolding, is required for epidermal growth factor receptor transactivation and cardiomyocyte hypertrophy via the angiotensin type 1 receptor.

Epidermal growth factor- and hepatocyte growth factor-receptor activity in serum-free cultures of human hepatocytes.

PubMed

Runge, D M; Runge, D; Dorko, K; Pisarov, L A; Leckel, K; Kostrubsky, V E; Thomas, D; Strom, S C; Michalopoulos, G K

1999-02-01

Serum-free primary cultures of hepatocytes are a useful tool to study factors triggering hepatocyte proliferation and regeneration. We have developed a chemically defined serum-free system that allows human hepatocyte proliferation in the presence of epidermal growth factor and hepatocyte growth factor. DNA synthesis and accumulation were determined by [3H]thymidine incorporation and fluorometry, respectively. Western blot analyses and co-immunoprecipitations were used to investigate the association of proteins involved in epidermal growth factor and hepatocyte growth factor activation and signaling: epidermal growth factor receptor, hepatocyte growth factor receptor (MET), urokinase-type plasminogen activator and its receptor, and a member of the signal transducer and activator of transcription family, STAT-3. Primary human hepatocytes proliferated under serum-free conditions in a chemically defined medium for up to 12 days. Epidermal growth factor-receptor and MET were present and functional, decreasing over time. MET, urokinase-type plasminogen activator and urokinase-type plasminogen activator receptor co-precipitated to varying degrees during the culture period. STAT-3 co-precipitated with epidermal growth factor-receptor and MET to varying degrees. Proliferation of human hepatocytes can improve by modification of a chemically defined medium originally used for rat hepatocyte cultures. In these long-term cultures of human hepatocytes, hepatocyte growth factor and epidermal growth factor can stimulate growth and differentiation by interacting with their receptors and initiating downstream signaling. This involves complex formation of the receptors with other plasma membrane components for MET (urokinase-type plasminogen activator in context of its receptor) and activation of STAT-3 for both receptors.

Growth factor involvement in tension-induced skeletal muscle growth

NASA Technical Reports Server (NTRS)

Vandenburgh, Herman H.

1993-01-01

Long-term manned space travel will require a better understanding of skeletal muscle atrophy which results from microgravity. Astronaut strength and dexterity must be maintained for normal mission operations and for emergency situations. Although exercise in space slows the rate of muscle loss, it does not prevent it. A biochemical understanding of how gravity/tension/exercise help to maintain muscle size by altering protein synthesis and/or degradation rate should ultimately allow pharmacological intervention to prevent muscle atrophy in microgravity. The overall objective is to examine some of the basic biochemical processes involved in tension-induced muscle growth. With an experimental in vitro system, the role of exogenous and endogenous muscle growth factors in mechanically stimulated muscle growth are examined. Differentiated avian skeletal myofibers can be 'exercised' in tissue culture using a newly developed dynamic mechanical cell stimulator device which simulates different muscle activity patterns. Patterns of mechanical activity which significantly affect muscle growth and metabolic characteristics were found. Both exogenous and endogenous growth factors are essential for tension-induced muscle growth. Exogenous growth factors found in serum, such as insulin, insulin-like growth factors, and steroids, are important regulators of muscle protein turnover rates and mechanically-induced muscle growth. Endogenous growth factors are synthesized and released into the culture medium when muscle cells are mechanically stimulated. At least one family of mechanically induced endogenous factors, the prostaglandins, help to regulate the rates of protein turnover in muscle cells. Endogenously synthesized IGF-1 is another. The interaction of muscle mechanical activity and these growth factors in the regulation of muscle protein turnover rates with our in vitro model system is studied.

Prognostic implication of serum hepatocyte growth factor in stage II/III breast cancer patients who received neoadjuvant chemotherapy.

PubMed

Kim, Hyori; Youk, Jeonghwan; Yang, Yaewon; Kim, Tae-Yong; Min, Ahrum; Ham, Hye-Seon; Cho, Seongcheol; Lee, Kyung-Hun; Keam, Bhumsuk; Han, Sae-Won; Oh, Do-Youn; Ryu, Han Suk; Han, Wonshik; Park, In Ae; Kim, Tae-You; Noh, Dong-Young; Im, Seock-Ah

2016-03-01

In stage II/III breast cancer, neoadjuvant chemotherapy (NAC) is a standard treatment. Although several biomarkers are used to predict prognosis in breast cancer, there is no reliable predictive biomarker for NAC success. Recently, the hepatocyte growth factor (HGF) and cMet signaling pathway demonstrated to be involved in breast cancer tumor progression, and its potential as a biomarker is under active investigation. In this study, we assessed the potential of serum HGF as a prognostic biomarker for NAC efficacy. Venous blood samples were drawn from patients diagnosed with stage II/III breast cancer and treated with NAC in Seoul National University Hospital from August 2004 to November 2009. Serum HGF level was determined using an ELISA system. We reviewed the medical records of the patients and investigated the association of HGF level with patients' clinicopathologic characteristics. A total of 121 female patients (median age = 45 years old) were included. Median level of HGF was 934 pg/ml (lower quartile: 772, upper quartile: 1145 pg/ml). Patients with higher HGF level than median value were significantly more likely to have clinically detectable regional node metastasis (p = 0.017, Fisher's exact test). Patients with complete and partial response according to the American Joint Committee on Cancer 7th Edition criteria tended to have higher HGF level (p = 0.105 by t test). Patients with an HGF level higher than the upper quartile value had longer relapse-free survival than the other patients (106 vs. 85 months, p = 0.008). High serum HGF levels in breast cancer patients are associated with clinically detectable regional node metastasis and, paradoxically, with longer relapse-free survival in stage II/III breast cancer.

Crk synergizes with epidermal growth factor for epithelial invasion and morphogenesis and is required for the met morphogenic program.

PubMed

Lamorte, Louie; Rodrigues, Sonia; Naujokas, Monica; Park, Morag

2002-10-04

Activation of the Met receptor tyrosine kinase through its ligand, hepatocyte growth factor, stimulates cell spreading, cell dispersal, and the inherent morphogenic program of various epithelial cell lines. Although both hepatocyte growth factor and epidermal growth factor (EGF) can activate downstream signaling pathways in Madin-Darby canine kidney epithelial cells, EGF fails to promote the breakdown of cell-cell junctional complexes and initiate an invasive morphogenic program. We have undertaken a strategy to identify signals that synergize with EGF in this process. We provide evidence that the overexpression of the CrkII adapter protein complements EGF-stimulated pathways to induce cell dispersal in two-dimensional cultures and cell invasion and branching morphogenesis in three-dimensional collagen gels. This finding correlates with the ability of CrkII to promote the breakdown of adherens junctions in stable cell lines and the ability of EGF to stimulate enhanced Rac activity in cells overexpressing CrkII. We have previously shown that the Gab1-docking protein is required for branching morphogenesis downstream of the Met receptor. Consistent with a role for CrkII in promoting EGF-dependent branching morphogenesis, the binding of Gab1 to CrkII is required for the branching morphogenic program downstream of Met. Together, our data support a role for the CrkII adapter protein in epithelial invasion and morphogenesis and underscores the importance of considering the synergistic actions of signaling pathways in cancer progression.

Growth in individuals with Majewski osteodysplastic primordial dwarfism type II caused by pericentrin mutations.

PubMed

Bober, Michael B; Niiler, Tim; Duker, Angela L; Murray, Jennie E; Ketterer, Tara; Harley, Margaret E; Alvi, Sabah; Flora, Christina; Rustad, Cecilie; Bongers, Ernie M H F; Bicknell, Louise S; Wise, Carol; Jackson, Andrew P

2012-11-01

Microcephalic primordial dwarfism (MPD) is a class of disorders characterized by intrauterine growth restriction (IUGR), impaired postnatal growth and microcephaly. Majewski osteodysplastic primordial dwarfism type II (MOPD II) is one of the more common conditions within this group. MOPD II is caused by truncating mutations in pericentrin (PCNT) and is inherited in an autosomal recessive manner. Detailed growth curves for length, weight, and OFC are presented here and derived from retrospective data from 26 individuals with MOPD II confirmed by molecular or functional studies. Severe pre- and postnatal growth failure is evident in MOPD II patients. The length, weight, and OFC at term (when corrected for gestational age) were -7.0, -3.9, and -4.6 standard deviation (SD) below the population mean and equivalent to the 50th centile of a 28-29-, 31-32-, and 30-31-week neonate, respectively. While at skeletal maturity, the height, weight, and OFC were -10.3, -14.3, and -8.5 SD below the population mean and equivalent to the size of 3-year 10- to 11-month-old, a 5-year 2- to 3-month-old, and 5- to 6-month-old, respectively. During childhood, MOPD II patients grow with slowed, but fairly constant growth velocities and show no evidence of any pubertal growth spurt. Treatment with human growth hormone (n = 11) did not lead to any significant improvement in final stature. The growth charts presented here will be of assistance with diagnosis and management of MOPD II, and should have particular utility in nutritional management of MOPD II during infancy. Copyright © 2012 Wiley Periodicals, Inc.

Neonatal hyperthyroidism impairs epinephrine-provoked secretion of nerve growth factor and epidermal growth factor in mouse saliva.

PubMed

Lakshmanan, J; Landel, C P

1986-07-01

We examined long-term effects of neonatal hyperthyroidism on salivary secretions of nerve growth factor and epidermal growth factor in male and female mice at the age of 31 days. Hyperthyroidism was induced by thyroxine (T4) injections (0.4 microgram/g body weight/day) during days 0-6. Littermate control mice were treated with vehicle. T4 treatment did not alter the amounts of protein secreted into saliva but hormone administration induced alteration in the types of protein secreted. T4 treatment decreased the contents of both nerve growth factor and epidermal growth factor secreted into the saliva. A Sephadex G-200 column chromatographic profile revealed the presence of two distinct nerve growth factor immunoreactive peaks, while epidermal growth factor immunoreactivity predominantly eluted as a single low molecular weight form. T4 treatment did not alter the molecular nature of their secretion, but the treatment decreased their contents. These results indicate an impairment in salivary secretion of nerve growth factor and epidermal growth factor long after T4 treatment has been discontinued.

Postnatally elevated levels of insulin-like growth factor (IGF)-II fail to rescue the dwarfism of IGF-I-deficient mice except kidney weight.

PubMed

Moerth, Corinna; Schneider, Marlon R; Renner-Mueller, Ingrid; Blutke, Andreas; Elmlinger, Martin W; Erben, Reinhold G; Camacho-Hübner, Cecilia; Hoeflich, Andreas; Wolf, Eckhard

2007-01-01

This study tested whether elevated levels of IGF-II in the postnatal period can rescue the dwarfism in IGF-I-deficient mice. Heterozygous Igf1 mutant mice [I(+/-) II(wt)] were crossed with heterozygous Igf1 mutant, phosphoenolpyruvate carboxykinase promoter IGF-II transgenic mice [I(+/-) II(tg)], and [I(+/+) II(wt)], [I(+/+) II(tg)], [I(-/-) II(wt)], and [I(-/-) II(tg)] offspring were investigated. IGF-II levels were 11- and 6-fold higher in male and female [I(-/-) II(tg)] vs. [I(-/-) II(wt)] animals. Western ligand blot analysis revealed markedly reduced activities of 30- and 32-kDa IGF binding proteins (IGFBPs) (most likely IGFBP-1 and IGFBP-2) and the 39- to 43-kDa IGFBP-3 double band in serum from IGF-I-deficient mice. These binding proteins were partially restored by overexpression of IGF-II. Analysis of weight data from the early postnatal period until d 60 showed that, in the absence of IGF-I, elevated levels of IGF-II have no effect on body weight gain. A detailed analysis of body proportions, bone parameters, and organ weights of 60-d-old mice also failed to show effects of IGF-II with one important exception: in Igf1 mutant and also Igf1 intact male mice, IGF-II overexpression significantly increased absolute (+32.4 and +28.6%; P < 0.01) and relative kidney weights (+29.0 and +22.4%; P < 0.001). These changes in kidney weight were associated with reduced phosphorylation of p38 MAPK. In summary, our genetic model shows that substantial amounts of IGF-II in the circulation do not rescue the postnatal growth deficit of IGF-I-deficient mice but increase absolute and relative kidney weights of normal and IGF-I-deficient male mice, suggesting a gender-specific role of IGF-II for kidney growth.

Fibroblast growth factor receptors in breast cancer.

PubMed

Wang, Shuwei; Ding, Zhongyang

2017-05-01

Fibroblast growth factor receptors are growth factor receptor tyrosine kinases, exerting their roles in embryogenesis, tissue homeostasis, and development of breast cancer. Recent genetic studies have identified some subtypes of fibroblast growth factor receptors as strong genetic loci associated with breast cancer. In this article, we review the recent epidemiological findings and experiment results of fibroblast growth factor receptors in breast cancer. First, we summarized the structure and physiological function of fibroblast growth factor receptors in humans. Then, we discussed the common genetic variations in fibroblast growth factor receptors that affect breast cancer risk. In addition, we also introduced the potential roles of each fibroblast growth factor receptors isoform in breast cancer. Finally, we explored the potential therapeutics targeting fibroblast growth factor receptors for breast cancer. Based on the biological mechanisms of fibroblast growth factor receptors leading to the pathogenesis in breast cancer, targeting fibroblast growth factor receptors may provide new opportunities for breast cancer therapeutic strategies.

Liposomal gene transfer of keratinocyte growth factor improves wound healing by altering growth factor and collagen expression.

PubMed

Pereira, Clifford T; Herndon, David N; Rocker, Roland; Jeschke, Marc G

2007-05-15

Growth factors affect the complex cascade of wound healing; however, interaction between different growth factors during dermal and epidermal regeneration are still not entirely defined. In the present study, we thought to determine the interaction between keratinocyte growth factor (KGF) administered as liposomal cDNA with other dermal and epidermal growth factors and collagen synthesis in an acute wound. Rats received an acute wound and were divided into two groups to receive weekly subcutaneous injections of liposomes plus the Lac-Z gene (0.22 microg, vehicle), or liposomes plus the KGF cDNA (2.2 microg) and Lac-Z gene (0.22 microg). Histological and immunohistochemical techniques were used to determine growth factor, collagen expression, and dermal and epidermal structure. KGF cDNA increased insulin-like growth factor-I (IGF-I), insulin-like growth factor binding protein-3 (IGFBP-3), and fibroblast growth factor (FGF), decreased transforming growth factor-beta (TGF-beta), while it had no effect on platelet-derived growth factor (PDGF) levels in the wound. KGF cDNA significantly increased collagen Type IV at both the wound edge as well as the wound bed, while it had no effect on collagen Type I and III. KGF cDNA increased re-epithelialization, improved dermal regeneration, and increased neovascularization. Exogenous administered KGF cDNA causes increases in IGF-I, IGF-BP3, FGF, and collagen IV and decreases TGF-beta concentration. KGF gene transfer accelerates wound healing without causing an increase in collagen I or III.

Rearing Mozambique tilapia in tidally-changing salinities: Effects on growth and the growth hormone/insulin-like growth factor I axis.

PubMed

Moorman, Benjamin P; Yamaguchi, Yoko; Lerner, Darren T; Grau, E Gordon; Seale, Andre P

2016-08-01

The growth hormone (GH)/insulin-like growth factor (IGF) axis plays a central role in the regulation of growth in teleosts and has been shown to be affected by acclimation salinity. This study was aimed at characterizing the effects of rearing tilapia, Oreochromis mossambicus, in a tidally-changing salinity on the GH/IGF axis and growth. Tilapia were raised in fresh water (FW), seawater (SW), or in a tidally-changing environment, in which salinity is switched between FW (TF) and SW (TS) every 6h, for 4months. Growth was measured over all time points recorded and fish reared in a tidally-changing environment grew significantly faster than other groups. The levels of circulating growth hormone (GH), insulin-like growth factor I (IGF-I), pituitary GH mRNA, gene expression of IGF-I, IGF-II, and growth hormone receptor 2 (GHR) in the muscle and liver were also determined. Plasma IGF-I was higher in FW and TS than in SW and TF tilapia. Pituitary GH mRNA was higher in TF and TS than in FW and SW tilapia. Gene expression of IGF-I in the liver and of GHR in both the muscle and liver changed between TF and TS fish. Fish growth was positively correlated with GH mRNA expression in the pituitary, and GHR mRNA expression in muscle and liver tissues. Our study indicates that rearing fish under tidally-changing salinities elicits a distinct pattern of endocrine regulation from that observed in fish reared in steady-state conditions, and may provide a new approach to increase tilapia growth rate and study the regulation of growth in euryhaline fish. Copyright © 2016 Elsevier Inc. All rights reserved.

Insulin-like growth factor-1, insulin-like growth factor binding protein-3 and lobule type in the Nurses' Health Study II.

PubMed

Rice, Megan S; Tamimi, Rulla M; Connolly, James L; Collins, Laura C; Shen, Dejun; Pollak, Michael N; Rosner, Bernard; Hankinson, Susan E; Tworoger, Shelley S

2012-03-13

Previous research in the Nurses' Health Study (NHS) and the NHSII observed that, among women diagnosed with benign breast disease (BBD), those with predominant type 1/no type 3 lobules (a marker of complete involution) versus other lobule types were at lower risk of subsequent breast cancer. Studies in animal models suggest that insulin-like growth factor-1 (IGF-1) may inhibit involution of lobules in the breast; however, this has not been studied in humans. We conducted a cross-sectional study among 472 women in the NHSII who were diagnosed with biopsy-confirmed proliferative BBD between 1991 and 2002 and provided blood samples between 1996 and 1999. A pathologist, blinded to exposure status, classified lobule type in normal adjacent tissue on available biopsy slides according to the number of acini per lobule. For each participant, the pathologist determined the predominant lobule type (that is, type 1, type 2, or type 3) and whether any type 1 or any type 3 lobules were present. Lobule type was then classified as: predominant type 1/no type 3 lobules, which is suggestive of complete involution; or other lobule types. Multivariate logistic models were used to assess the associations between plasma IGF-1, insulin-like growth factor binding protein-3 (IGFBP-3), and the ratio of IGF-1:IGFBP-3 levels with lobule type. In univariate analyses, greater age, higher body mass index, postmenopausal status, nulliparity, and lower IGF-1 levels were associated with predominant type 1/no type 3 lobules (P < 0.05). In multivariate models adjusting for age and assay batch, higher IGF-1 levels were associated with decreased odds of predominant type 1/no type 3 lobules (odds ratio quartile 4 vs. quartile 1 = 0.37, 95% confidence interval = 0.15 to 0.89). Greater ratios of IGF-1:IGFBP-3 levels were also associated with decreased odds of predominant type 1/no type 3 lobules (odds ratio quartile 4 vs. quartile 1 = 0.26, 95% confidence interval = 0.11 to 0.64). These results were

New microbial growth factor

NASA Technical Reports Server (NTRS)

Bok, S. H.; Casida, L. E., Jr.

1977-01-01

A screening procedure was used to isolate from soil a Penicillium sp., two bacterial isolates, and a Streptomyces sp. that produced a previously unknown microbial growth factor. This factor was an absolute growth requirement for three soil bacteria. The Penicillium sp. and one of the bacteria requiring the factor, an Arthrobacter sp., were selected for more extensive study concerning the production and characteristics of the growth factor. It did not seem to be related to the siderochromes. It was not present in soil extract, rumen fluid, or any other medium component tested. It appears to be a glycoprotein of high molecular weight and has high specific activity. When added to the diets for a meadow-vole mammalian test system, it caused an increased consumption of diet without a concurrent increase in rate of weight gain.

c-Ski overexpression promotes tumor growth and angiogenesis through inhibition of transforming growth factor-beta signaling in diffuse-type gastric carcinoma.

PubMed

Kiyono, Kunihiko; Suzuki, Hiroshi I; Morishita, Yasuyuki; Komuro, Akiyoshi; Iwata, Caname; Yashiro, Masakazu; Hirakawa, Kosei; Kano, Mitsunobu R; Miyazono, Kohei

2009-10-01

c-Ski, originally identified as a proto-oncogene product, is an important negative regulator of transforming growth factor (TGF)-beta family signaling through interaction with Smad2, Smad3, and Smad4. High expression of c-Ski has been found in some cancers, including gastric cancer. We previously showed that disruption of TGF-beta signaling by dominant-negative TGF-beta type II receptor in a diffuse-type gastric carcinoma model accelerated tumor growth through induction of tumor angiogenesis by decreased expression of the anti-angiogenic factor thrombospondin (TSP)-1. Here, we examined the function of c-Ski in human diffuse-type gastric carcinoma OCUM-2MLN cells. Overexpression of c-Ski inhibited TGF-beta signaling in OCUM-2MLN cells. Interestingly, c-Ski overexpression resulted in extensive acceleration of the growth of subcutaneous xenografts in BALB/c nu/nu female mice (6 weeks of age). Similar to tumors expressing dominant-negative TGF-beta type II receptor, histochemical studies revealed less fibrosis and increased angiogenesis in xenografted tumors expressing c-Ski compared to control tumors. Induction of TSP-1 mRNA by TGF-beta was attenuated by c-Ski in vitro, and expression of TSP-1 mRNA was decreased in tumors expressing c-Ski in vivo. These findings suggest that c-Ski overexpression promotes the growth of diffuse-type gastric carcinoma through induction of angiogenesis.

Laser-induced thermotherapy (LITT) elevates mRNA expression of connective tissue growth factor (CTGF) associated with reduced tumor growth of liver metastases compared to hepatic resection.

PubMed

Isbert, Christoph; Ritz, Jörg-Peter; Roggan, André; Schuppan, Detlef; Ajubi, Navid; Buhr, Heinz Johannes; Hohenberger, Werner; Germer, Christoph-Thomas

2007-01-01

Proliferation and synthesis of hepatocellular tissue after tissue damage are promoted by specific growth factors such as hepatic tissue growth factor (HGF) and connective growth factor (CTGF). Laser-induced thermotherapy (LITT) for the treatment of liver metastases is deemed to be a parenchyma-saving procedure compared to hepatic resection. The aim of this study was to compare the impact of LITT and hepatic resection on intrahepatic residual tumor tissue and expression levels of mRNA HGF/CTGF within liver and tumor tissue. Two independent adenocarcinomas (CC531) were implanted into 75 WAG rats, one in the right (untreated tumor) and one in the left liver lobe (treated tumor). The left lobe tumor was treated either by LITT or partial hepatectomy. The control tumor was submitted to in-situ hybridization of HGF and CTGF 24-96 hours and 14 days after intervention. Volumes of the untreated tumors prior to intervention were 38+/-8 mm(3) in group I (laser), 39 +/- 7 mm(3) in group II (resection), and 42 +/- 12 mm(3) in group III (control) and did not differ significantly (P > 0.05). Fourteen days after the intervention the mean tumor+/-SEM volume of untreated tumor in group I (laser) [223 +/- 36] was smaller than in group II (resection) [1233.28 +/- 181.52; P < 0.001], and in group III (control) [978.92 +/- 87.57; P < 0.003]. Forty-eight hours after the intervention intrahepatic mRNA expression level of HGF in group II (resection) was almost twofold higher than in group I (laser) [7.2 +/- 1.0 c/mf vs. 3.9 +/- 0.4 c/mf; P<0.01]. Fourteen days after the intervention intrahepatic mRNA expression level of CTGF in group I (laser) was higher than in group II (resection) [13.89 +/- 0.77 c/mf vs. 9.09 +/- 0.78 c/mf; P < 0.003]. LITT leads to a decrease of residual tumor growth in comparison to hepatic resection. Accelerated tumor growth after hepatic resection is associated with higher mRNA level of HGF and reduced tumor growth after LITT with higher mRNA level of CTGF. The

Factors That Influence Language Growth.

ERIC Educational Resources Information Center

McCarthy, Dorothea, Ed.; And Others

This booklet contains four articles that discuss factors influencing language growth. The first, "The Child's Equipment for Language Growth" by Charlotte Wells, examines what the child needs for language learning, how the child uses his equipment for language growth, and what school factors facilitate the child's use of his equipment for language…

Relationships Between RNA Polymerase II Activity and Spt Elongation Factors to Spt- Phenotype and Growth in Saccharomyces cerevisiae

PubMed Central

Cui, Ping; Jin, Huiyan; Vutukuru, Manjula Ramya; Kaplan, Craig D.

2016-01-01

The interplay between adjacent transcription units can result in transcription-dependent alterations in chromatin structure or recruitment of factors that determine transcription outcomes, including the generation of intragenic or other cryptic transcripts derived from cryptic promoters. Mutations in a number of genes in Saccharomyces cerevisiae confer both cryptic intragenic transcription and the Suppressor of Ty (Spt-) phenotype for the lys2-128∂ allele of the LYS2 gene. Mutants that suppress lys2-128∂ allow transcription from a normally inactive Ty1 ∂ promoter, conferring a LYS+ phenotype. The arrangement of transcription units at lys2-128∂ is reminiscent of genes containing cryptic promoters within their open reading frames. We set out to examine the relationship between RNA Polymerase II (Pol II) activity, functions of Spt elongation factors, and cryptic transcription because of the previous observation that increased-activity Pol II alleles confer an Spt- phenotype. We identify both cooperating and antagonistic genetic interactions between Pol II alleles and alleles of elongation factors SPT4, SPT5, and SPT6. We find that cryptic transcription at FLO8 and STE11 is distinct from that at lys2-128∂, though all show sensitivity to reduction in Pol II activity, especially the expression of lys2-128∂ found in Spt- mutants. We determine that the lys2-128∂ Spt- phenotypes for spt6-1004 and increased activity rpo21/rpb1 alleles each require transcription from the LYS2 promoter. Furthermore, we identify the Ty1 transcription start site (TSS) within the ∂ element as the position of Spt- transcription in tested Spt- mutants. PMID:27261007

Insulin-like growth factor 1: common mediator of multiple enterotrophic hormones and growth factors.

PubMed

Bortvedt, Sarah F; Lund, P Kay

2012-03-01

To summarize the recent evidence that insulin-like growth factor 1 (IGF1) mediates growth effects of multiple trophic factors and discuss clinical relevance. Recent reviews and original reports indicate benefits of growth hormone (GH) and long-acting glucagon-like peptide 2 (GLP2) analogs in short bowel syndrome and Crohn's disease. This review highlights the evidence that biomarkers of sustained small intestinal growth or mucosal healing and evaluation of intestinal epithelial stem cell biomarkers may improve clinical measures of intestinal growth or response to trophic hormones. Compelling evidence that IGF1 mediates growth effects of GH and GLP2 on intestine or linear growth in preclinical models of resection or Crohn's disease is presented, along with a concept that these hormones or IGF1 may enhance sustained growth if given early after bowel resection. Evidence that suppressor of cytokine signaling protein induction by GH or GLP2 in normal or inflamed intestine may limit IGF1-induced growth, but protect against risk of dysplasia or fibrosis, is reviewed. Whether IGF1 receptor mediates IGF1 action and potential roles of insulin receptors are addressed. IGF1 has a central role in mediating trophic hormone action in small intestine. Better understanding of benefits and risks of IGF1, receptors that mediate IGF1 action, and factors that limit undesirable growth are needed.

FGF growth factor analogs

DOEpatents

Zamora, Paul O [Gaithersburg, MD; Pena, Louis A [Poquott, NY; Lin, Xinhua [Plainview, NY; Takahashi, Kazuyuki [Germantown, MD

2012-07-24

The present invention provides a fibroblast growth factor heparin-binding analog of the formula: ##STR00001## where R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, X, Y and Z are as defined, pharmaceutical compositions, coating compositions and medical devices including the fibroblast growth factor heparin-binding analog of the foregoing formula, and methods and uses thereof.

Growth factors in porcine full and partial thickness burn repair. Differing targets and effects of keratinocyte growth factor, platelet-derived growth factor-BB, epidermal growth factor, and neu differentiation factor.

PubMed Central

Danilenko, D. M.; Ring, B. D.; Tarpley, J. E.; Morris, B.; Van, G. Y.; Morawiecki, A.; Callahan, W.; Goldenberg, M.; Hershenson, S.; Pierce, G. F.

1995-01-01

The topical application of recombinant growth factors such as epidermal growth factor, platelet-derived growth factor-BB homodimer (rPDGF-BB), keratinocyte growth factor (rKGF), and neu differentiation factor has resulted in significant acceleration of healing in several animal models of wound repair. In this study, we established highly reproducible and quantifiable full and deep partial thickness porcine burn models in which burns were escharectomized 4 or 5 days postburn and covered with an occlusive dressing to replicate the standard treatment in human burn patients. We then applied these growth factors to assess their efficacy on several parameters of wound repair: extracellular matrix and granulation tissue production, percent reepithelialization, and new epithelial area. In full thickness burns, only rPDGF-BB and the combination of rPDGF-BB and rKGF induced significant changes in burn repair. rPDGF-BB induced marked extracellular matrix and granulation tissue production (P = 0.013) such that the burn defect was filled within several days of escharectomy, but had no effect on new epithelial area or reepithelialization. The combination of rPDGF-BB and rKGF in full thickness burns resulted in a highly significant increase in extracellular matrix and granulation tissue area (P = 0.0009) and a significant increase in new epithelial area (P = 0.007), but had no effect on reepithelialization. In deep partial thickness burns, rKGF induced the most consistent changes. Daily application of rKGF induced a highly significant increase in new epithelial area (P < 0.0001) but induced only a modest increase in reepithelialization (83.7% rKGF-treated versus 70.2% control; P = 0.016) 12 days postburn. rKGF also doubled the number of fully reepithelialized burns (P = 0.02) at 13 days postburn, at least partially because of marked stimulation of both epidermal and follicular proliferation as assessed by proliferating cell nuclear antigen expression. In situ hybridization for

Regulation of Transforming Growth Factor β1, Platelet-Derived Growth Factor, and Basic Fibroblast Growth Factor by Silicone Gel Sheeting in Early-Stage Scarring.

PubMed

Choi, Jaehoon; Lee, Eun Hee; Park, Sang Woo; Chang, Hak

2015-01-01

Hypertrophic scars and keloids are associated with abnormal levels of growth factors. Silicone gel sheets are effective in treating and preventing hypertrophic scars and keloids. There has been no report on the change in growth factors in the scar tissue following the use of silicone gel sheeting for scar prevention. A prospective controlled trial was performed to evaluate whether growth factors are altered by the application of a silicone gel sheet on a fresh surgical scar. Four of seven enrolled patients completed the study. Transforming growth factor (TGF)-β1, platelet-derived growth factor (PDGF), and basic fibroblast growth factor (bFGF) were investigated immunohistochemically in biopsies taken from five scars at 4 months following surgery. In both the epidermis and the dermis, the expression of TGF-β1 (P=0.042 and P=0.042) and PDGF (P=0.043 and P=0.042) was significantly lower in the case of silicone gel sheet-treated scars than in the case of untreated scars. The expression of bFGF in the dermis was significantly higher in the case of silicone gel sheet-treated scars than in the case of untreated scars (P=0.042), but in the epidermis, the expression of bFGF showed no significant difference between the groups (P=0.655). The levels of TGF-β1, PDGF, and bFGF are altered by the silicone gel sheet treatment, which might be one of the mechanisms of action in scar prevention.

The roles of vascular endothelial growth factor in bone repair and regeneration

PubMed Central

Hu, Kai; Olsen, Bjorn R.

2016-01-01

Vascular endothelial growth factor-A (VEGF) is one of the most important growth factors for regulation of vascular development and angiogenesis. Since bone is a highly vascularized organ and angiogenesis plays an important role in osteogenesis, VEGF also influences skeletal development and postnatal bone repair. Compromised bone repair and regeneration in many patients can be attributed to impaired blood supply; thus, modulation of VEGF levels in bones represents a potential strategy for treating compromised bone repair and improving bone regeneration. This review (i) summarizes the roles of VEGF at different stages of bone repair, including the phases of inflammation, endochondral ossification, intramembranous ossification during callus formation and bone remodeling; (ii) discusses different mechanisms underlying the effects of VEGF on osteoblast function, including paracrine, autocrine and intracrine signaling during bone repair; (iii) summarizes the role of VEGF in the bone regenerative procedure, distraction osteogenesis; and (iv) reviews evidence for the effects of VEGF in the context of repair and regeneration techniques involving the use of scaffolds, skeletal stem cells and growth factors. PMID:27353702

Growth factors, nutrient signaling, and cardiovascular aging.

PubMed

Fontana, Luigi; Vinciguerra, Manlio; Longo, Valter D

2012-04-13

Growth factors regulated by specific macronutrients have been shown to promote aging and accelerate mortality in the majority of the organisms studied. In particular, the enzymes activated by growth hormone, insulin, and insulin-like growth factor-1 in mammals and their orthologs in simple model organisms represent perhaps the best-understood proteins involved in the aging process. Dietary restriction, which reduces the level of insulin-like growth factor-1 and of other growth factors, has been associated with protection from diabetes, cancer, and cardiovascular diseases, and deficiencies in growth hormone signaling and insulin-like growth factor-1 are strongly associated with protection from cancer and diabetes in both mice and humans; however, their role in cardiac function and cardiovascular diseases is controversial. Here, we review the link between growth factors, cardiac function, and heart disease with focus on the cardioprotective and sensitizing effect of growth factors in both model organisms and humans.

Effects of Artesunate on the Expressions of Insulin-Like Growth Factor-1, Osteopontin and C-Telopeptides of Type II Collagen in a Rat Model of Osteoarthritis.

PubMed

Bai, Zhe; Guo, Xiao-Hui; Tang, Chi; Yue, Si-Tong; Shi, Long; Qiang, Bo

2018-01-01

The study aims to explore the effects of artesunate on insulin-like growth factor-1 (IGF-1), Osteopontin (OPN), and C-telopeptides of type II collagen (CTX-II) in serum, synovial fluid (SF), and cartilage tissues of rats with osteoarthritis (OA). OA models were established. Normal model, artesunate, and Viatril-S groups (20 rats respectively) were set. Enzyme-linked immunosorbent assay, IHC staining, and quantitative real-time polymerase chain reaction were conducted to calculate IGF-1, OPN, and CTX-II levels in serum, SF, and cartilage tissues of rats. The pathological changes in cartilage tissues were evaluated with Mankin score and Hematoxylin-Eosin staining. Compared with the normal group, the model group showed increased IGF-1 level; decreased OPN, CTX-II levels in the serum and SF; and contrary results were seen in the cartilage tissues. A gradual ascending IGF-1 level and descending OPN and CTX-II levels existed in the serum and SF in the artesunate and Viatril-S groups after 2 weeks. The model group showed the most obvious pathological changes and highest Mankin score compared with the other groups. Higher IGF-1 level and lower OPN, CTX-II levels were exhibited in the cartilage tissue in the artesunate and Viatril-S groups but not in the model group. Artesunate and Viatril-S inhibit OA development by elevating IGF-1 level and reducing OPN and CTX-II levels. © 2017 S. Karger AG, Basel.

SphK1 inhibitor II (SKI-II) inhibits acute myelogenous leukemia cell growth in vitro and in vivo

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Li; Weng, Wei; Sun, Zhi-Xin

Previous studies have identified sphingosine kinase 1 (SphK1) as a potential drug target for treatment of acute myeloid leukemia (AML). In the current study, we investigated the potential anti-leukemic activity of a novel and specific SphK1 inhibitor, SKI-II. We demonstrated that SKI-II inhibited growth and survival of human AML cell lines (HL-60 and U937 cells). SKI-II was more efficient than two known SphK1 inhibitors SK1-I and FTY720 in inhibiting AML cells. Meanwhile, it induced dramatic apoptosis in above AML cells, and the cytotoxicity by SKI-II was almost reversed by the general caspase inhibitor z-VAD-fmk. SKI-II treatment inhibited SphK1 activation, andmore » concomitantly increased level of sphingosine-1-phosphate (S1P) precursor ceramide in AML cells. Conversely, exogenously-added S1P protected against SKI-II-induced cytotoxicity, while cell permeable short-chain ceramide (C6) aggravated SKI-II's lethality against AML cells. Notably, SKI-II induced potent apoptotic death in primary human AML cells, but was generally safe to the human peripheral blood mononuclear cells (PBMCs) isolated from healthy donors. In vivo, SKI-II administration suppressed growth of U937 leukemic xenograft tumors in severe combined immunodeficient (SCID) mice. These results suggest that SKI-II might be further investigated as a promising anti-AML agent. - Highlights: • SKI-II inhibits proliferation and survival of primary and transformed AML cells. • SKI-II induces apoptotic death of AML cells, but is safe to normal PBMCs. • SKI-II is more efficient than two known SphK1 inhibitors in inhibiting AML cells. • SKI-II inhibits SphK1 activity, while increasing ceramide production in AML cells. • SKI-II dose-dependently inhibits U937 xenograft growth in SCID mice.« less

Insulin-like growth factor-I (lGF-l): safety and efficacy.

PubMed

Laron, Zvi

2004-11-01

Insulin-like growth factor I (IGF-I) is a peptide synthesized mainly in the liver by stimulation by pituitary growth hormone (GH). It circulates almost entirely bound to its binding proteins. It is the anabolic effector hormone of GH. It is the only treatment in states of GH resistance such as Laron syndrome and blocking antibodies to human GH. As it suppresses insulin and GH secretion it has been used in states of insulin resistance including Type II diabetes mellitus. IGF-I is administered by once or twice daily injections. Adverse effects are mostly caused by overdosage. The usual daily dose in children ranges from 100-200 microg/kg.

Growth/differentiation factor-11: an evolutionary conserved growth factor in vertebrates.

PubMed

Funkenstein, Bruria; Olekh, Elena

2010-11-01

Growth and differentiation factor-11 (GDF-11) is a member of the transforming growth factor-β superfamily and is thought to be derived together with myostatin (known also as GDF-8) from an ancestral gene. In the present study, we report the isolation and characterization of GDF-11 homolog from a marine teleost, the gilthead sea bream Sparus aurata, and show that this growth factor is highly conserved throughout vertebrates. Using bioinformatics, we identified GDF-11 in Tetraodon, Takifugu, medaka, and stickleback and found that they are highly conserved at the amino acid sequence as well as gene organization. Moreover, we found conservation of syntenic relationships among vertebrates in the GDF-11 locus. Transcripts for GDF-11 can be found in eggs and early embryos, albeit at low levels, while in post-hatching larvae expression levels are high and decreases as development progresses, suggesting that GDF-11 might have a role during early development of fish as found in tetrapods and zebrafish. Finally, GDF-11 is expressed in various tissues in the adult fish including muscle, brain, and eye.

Release kinetics of platelet-derived and plasma-derived growth factors from autologous plasma rich in growth factors.

PubMed

Anitua, Eduardo; Zalduendo, Mari Mar; Alkhraisat, Mohammad Hamdan; Orive, Gorka

2013-10-01

Many studies have evaluated the biological effects of platelet rich plasma reporting the final outcomes on cell and tissues. However, few studies have dealt with the kinetics of growth factor delivery by plasma rich in growth factors. Venous blood was obtained from three healthy volunteers and processed with PRGF-Endoret technology to prepare autologous plasma rich in growth factors. The gel-like fibrin scaffolds were then incubated in triplicate, in a cell culture medium to monitor the release of PDGF-AB, VEGF, HGF and IGF-I during 8 days of incubation. A leukocyte-platelet rich plasma was prepared employing the same technology and the concentrations of growth factors and interleukin-1β were determined after 24h of incubation. After each period, the medium was collected, fibrin clot was destroyed and the supernatants were stored at -80°C until analysis. The growth factor delivery is diffusion controlled with a rapid initial release by 30% of the bioactive content after 1h of incubation and a steady state release when almost 70% of the growth factor content has been delivered. Autologous fibrin matrix retained almost 30% of the amount of the growth factors after 8 days of incubation. The addition of leukocytes to the formula of platelet rich plasma did not increase the concentration of the growth factors, while it drastically increased the presence of pro-inflammatory IL-1β. Further studies employing an in vitro inflammatory model would be interesting to study the difference in growth factors and pro-inflammatory cytokines between leukocyte-free and leukocyte-rich platelet rich plasma. Copyright © 2013 Elsevier GmbH. All rights reserved.

Growth factor-induced morphological, physiological and molecular characteristics in cerebral endothelial cells.

PubMed

Krizbai, I A; Bauer, H; Amberger, A; Hennig, B; Szabó, H; Fuchs, R; Bauer, H C

2000-09-01

The capacity of vascular endothelial cells to modulate their phenotype in response to changes in environmental conditions is one of the most important characteristics of this cell type. Since different growth factors may play an important signalling role in this adaptive process we have investigated the effect of endothelial cell growth factor (ECGF) on morphological, physiological and molecular characteristics of cerebral endothelial cells (CECs). CECs grown in the presence of ECGF and its cofactor heparin exhibit an epithelial-like morphology (type I CECs). Upon removal of growth factors, CECs develop an elongated spindle-like shape (type II CECs) which is accompanied by the reorganization of actin filaments and the induction of alpha-actin expression. Since one of the most important functions of CECs is the creation of a selective diffusion barrier between the blood and the central nervous system (CNS), we have studied the expression of junction-related proteins in both cell types. We have found that removal of growth factors from endothelial cultures leads to the downregulation of cadherin and occludin protein levels. The loss of junctional proteins was accompanied by a significant increase in the migratory activity and an altered protease activity profile of the cells. TGF-beta1 suppressed endothelial migration in all experiments. Our data provide evidence to suggest that particular endothelial functions are largely controlled by the presence of growth factors. The differences in adhesiveness and migration may play a role in important physiological and pathological processes of endothelial cells such as vasculogenesis or tumor progression.

Antibody-directed neutralization of annexin II (ANX II) inhibits neoangiogenesis and human breast tumor growth in a xenograft model.

PubMed

Sharma, Meena; Blackman, Marc R; Sharma, Mahesh C

2012-02-01

Activation of the fibrinolytic pathway has long been associated with human breast cancer. Plasmin is the major end product of the fibrinolytic pathway and is critical for normal physiological functions. The mechanism by which plasmin is generated in breast cancer is not yet fully described. We previously identified annexin II (ANX II), a fibrinolytic receptor, in human breast tumor tissue samples and observed a strong positive correlation with advanced stage cancer (Sharma et al., 2006a). We further demonstrated that tissue plasminogen activator (tPA) binds to ANX II in invasive breast cancer MDA-MB231cells, which leads to plasmin generation (Sharma et al., 2010). We hypothesize that ANX II-dependent plasmin generation in breast tumor is necessary to trigger the switch to neoangiogenesis, thereby stimulating a more aggressive cancer phenotype. Our immunohistochemical studies of human breast tumor tissues provide compelling evidence of a strong positive correlation between ANX II expression and neoangiogenesis, and suggest that ANX II is a potential target to slow or inhibit breast tumor growth by inhibiting neoangiogenesis. We now report that administration of anti-ANX II antibody potently inhibits the growth of human breast tumor in a xenograft model. Inhibition of tumor growth is at least partly due to attenuation of neoangiogenic activity within the tumor. In vitro studies demonstrate that anti-ANX II antibody inhibits angiogenesis on three dimensional matrigel cultures by eliciting endothelial cell (EC) death likely due to apoptosis. Taken together, these data suggest that selective disruption of the fibrinolytic activity of ANX II may provide a novel strategy for specific inhibition of neoangiogenesis in human breast cancer. Published by Elsevier Inc.

Insulin-Like Growth Factor and Epidermal Growth Factor Signaling in Breast Cancer Cell Growth: Focus on Endocrine Resistant Disease

PubMed Central

Berdiaki, Aikaterini; Tzardi, Maria

2015-01-01

Breast cancer is the most common type of cancer for women worldwide with a lifetime risk amounting to a staggering total of 10%. It is well established that the endogenous synthesis of insulin-like growth factor (IGF) and epidermal growth factor (EGF) polypeptide growth factors are closely correlated to malignant transformation and all the steps of the breast cancer metastatic cascade. Numerous studies have demonstrated that both estrogens and growth factors stimulate the proliferation of steroid-dependent tumor cells, and that the interaction between these signaling pathways occurs at several levels. Importantly, the majority of breast cancer cases are estrogen receptor- (ER-) positive which have a more favorable prognosis and pattern of recurrence with endocrine therapy being the backbone of treatment. Unfortunately, the majority of patients progress to endocrine therapy resistant disease (acquired resistance) whereas a proportion of patients may fail to respond to initial therapy (de novo resistance). The IGF-I and EGF downstream signaling pathways are closely involved in the process of progression to therapy resistant disease. Modifications in the bioavailability of these growth factors contribute critically to disease progression. In the present review therefore, we will discuss in depth how IGF and EGF signaling participate in breast cancer pathogenesis and progression to endocrine resistant disease. PMID:26258011

Insulin-like growth factor I (IGF-1) Ec/Mechano Growth factor--a splice variant of IGF-1 within the growth plate.

PubMed

Schlegel, Werner; Raimann, Adalbert; Halbauer, Daniel; Scharmer, Daniela; Sagmeister, Susanne; Wessner, Barbara; Helmreich, Magdalena; Haeusler, Gabriele; Egerbacher, Monika

2013-01-01

Human insulin-like growth factor 1 Ec (IGF-1Ec), also called mechano growth factor (MGF), is a splice variant of insulin-like growth factor 1 (IGF-1), which has been shown in vitro as well as in vivo to induce growth and hypertrophy in mechanically stimulated or damaged muscle. Growth, hypertrophy and responses to mechanical stimulation are important reactions of cartilaginous tissues, especially those in growth plates. Therefore, we wanted to ascertain if MGF is expressed in growth plate cartilage and if it influences proliferation of chondrocytes, as it does in musculoskeletal tissues. MGF expression was analyzed in growth plate and control tissue samples from piglets aged 3 to 6 weeks. Furthermore, growth plate chondrocyte cell culture was used to evaluate the effects of the MGF peptide on proliferation. We showed that MGF is expressed in considerable amounts in the tissues evaluated. We found the MGF peptide to be primarily located in the cytoplasm, and in some instances, it was also found in the nucleus of the cells. Addition of MGF peptides was not associated with growth plate chondrocyte proliferation.

Subcritical crack growth in soda-lime glass in combined mode I and mode II loading

NASA Technical Reports Server (NTRS)

Singh, Dileep; Shetty, Dinesh K.

1990-01-01

Subcritical crack growth under mixed-mode loading was studied in soda-lime glass. Pure mode I, combined mode I and mode II, and pure mode II loadings were achieved in precracked disk specimens by loading in diametral compression at selected angles with respect to the symmetric radial crack. Crack growth was monitored by measuring the resistance changes in a microcircuit grid consisting of parallel, electrically conducting grid lines deposited on the surface of the disk specimens by photolithography. Subcritical crack growth rates in pure mode I, pure mode II, and combined mode I and mode II loading could be described by an exponential relationship between crack growth rate and an effective crack driving force derived from a mode I-mode II fracture toughness envelope. The effective crack driving force was based on an empirical representation of the noncoplanar strain energy release rate. Stress intensities for kinked cracks were assessed using the method of caustics and an initial decrease and a subsequent increase in the subcritical crack growth rates of kinked cracks were shown to correlate with the variations of the mode I and the mode II stress intensities.

The role of growth factors in maintenance of stemness in bone marrow-derived mesenchymal stem cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eom, Young Woo; Oh, Ji-Eun; Lee, Jong In

2014-02-28

Highlights: • Expression of FGF-2, FGF-4, EGF, and HGF decreased during long-term culture of BMSCs. • Loss of growth factors induced autophagy, senescence and decrease of stemness. • FGF-2 increased proliferation potential via AKT and ERK activation in BMSCs. • FGF-2 suppressed LC3-II expression and down-regulated senescence of BMSCs. • HGF was important in maintenance of the differentiation potential of BMSCs. - Abstract: Mesenchymal stem cells (MSCs) are an active topic of research in regenerative medicine due to their ability to secrete a variety of growth factors and cytokines that promote healing of damaged tissues and organs. In addition, thesemore » secreted growth factors and cytokines have been shown to exert an autocrine effect by regulating MSC proliferation and differentiation. We found that expression of EGF, FGF-4 and HGF were down-regulated during serial passage of bone marrow-derived mesenchymal stem cells (BMSCs). Proliferation and differentiation potentials of BMSCs treated with these growth factors for 2 months were evaluated and compared to BMSCs treated with FGF-2, which increased proliferation of BMSCs. FGF-2 and -4 increased proliferation potentials at high levels, about 76- and 26-fold, respectively, for 2 months, while EGF and HGF increased proliferation of BMSCs by less than 2.8-fold. Interestingly, differentiation potential, especially adipogenesis, was maintained only by HGF treatment. Treatment with FGF-2 rapidly induced activation of AKT and later induced ERK activation. The basal level of phosphorylated ERK increased during serial passage of BMSCs treated with FGF-2. The expression of LC3-II, an autophagy marker, was gradually increased and the population of senescent cells was increased dramatically at passage 7 in non-treated controls. But FGF-2 and FGF-4 suppressed LC3-II expression and down-regulated senescent cells during long-term (i.e. 2 month) cultures. Taken together, depletion of growth factors during serial

Growth factors for nanobacteria

NASA Astrophysics Data System (ADS)

Ciftcioglu, Neva; Kajander, E. Olavi

1999-12-01

Nanobacteria are novel microorganisms recently isolated from fetal bovine serum and blood of cows and humans. These coccoid, gram negative bacteria in alpha-2 subgroup of Proteobacteria grow slowly under mammalian cell culture conditions but not in common media for microbes. Now we have found two different kinds of culture supplement preparations that improve their growth and make them culturable in the classical sense. These are supernatant fractions of conditioned media obtained from 1 - 3 months old nanobacteria cultures and from about a 2 weeks old Bacillus species culture. Both improved multiplication and particle yields and the latter increased their resistance to gentamicin. Nanobacteria cultured with any of the methods shared similar immunological property, structure and protein pattern. The growth supporting factors were heat-stabile and nondialyzable, and dialysis improved the growth promoting action. Nanobacteria formed stony colonies in a bacteriological medium supplemented with the growth factors. This is an implication that nanobacterial growth is influenced by pre-existing bacterial flora.

A Phase II Safety and Efficacy Study of the Vascular Endothelial Growth Factor Receptor Tyrosine Kinase Inhibitor Pazopanib in Patients With Metastatic Urothelial Cancer

PubMed Central

Pili, Roberto; Qin, Rui; Flynn, P.J.; Picus, Joel; Millward, Michael; Ho, Wing Ming; Pitot, Henry; Tan, Winston; Miles, Kiersten M.; Erlichman, Charles; Vaishampayan, Ulka

2013-01-01

Vascular endothelial growth factor (VEGF) is expressed in human bladder tumors. A phase II study was conducted to assess the VEGF inhibitor pazopanib in patients with metastatic, urothelial carcinoma. Nineteen patients with one prior systemic therapy were enrolled. No objective responses were observed and median progression-free survival was 1.9 months. The role of anti-VEGF therapies in urothelial carcinoma remains to be determined. Background Vascular endothelial growth factor (VEGF) is produced by bladder cancer cell lines in vitro and expressed in human bladder tumor tissues. Pazopanib is a vascular endothelial receptor tyrosine kinase inhibitor with anti-angiogenesis and anti-tumor activity in several preclinical models. A 2-stage phase II study was conducted to assess the activity and toxicity profile of pazopanib in patients with metastatic, urothelial carcinoma. Methods Patients with one prior systemic therapy for metastatic urothelial carcinoma were eligible. Patients received pazopanib at a dose of 800 mg orally for a 4-week cycle. Results Nineteen patients were enrolled. No grade 4 or 5 events were experienced. Nine patients experienced 11 grade 3 adverse events. Most common toxicities were anemia, thrombocytopenia, leucopenia, and fatigue. For stage I, none of the first 16 evaluable patients were deemed a success (complete response or partial response) by the Response Evaluation Criteria In Solid Tumors criteria during the first four 4-week cycles of treatment. Median progression-free survival was 1.9 months. This met the futility stopping rule of interim analysis, and therefore the trial was recommended to be permanently closed. Conclusions Pazopanib did not show significant activity in patients with urothelial carcinoma. The role of anti-VEGF therapies in urothelial carcinoma may need further evaluation in rational combination strategies. PMID:23891158

Research on growth factors in periodontology.

PubMed

Smith, Patricio C; Martínez, Constanza; Cáceres, Mónica; Martínez, Jorge

2015-02-01

Growth factors play critical roles in periodontal repair through the regulation of cell behavior. Many of the cell responses regulated by these proteins include cell adhesion, migration, proliferation and differentiation. Periodontal regeneration involves an organized response of different cells, tissues and growth factors implicated in the coordination of these events. However, periodontal tissue reconstruction is an extremely difficult task. Multiple studies have been performed to understand the specific role of growth factors in periodontal wound healing. In the present review we analyze the evidence that supports the roles of growth factors in periodontal wound healing and regeneration. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Synthetic heparin-binding growth factor analogs

DOEpatents

Pena, Louis A.; Zamora, Paul; Lin, Xinhua; Glass, John D.

2007-01-23

The invention provides synthetic heparin-binding growth factor analogs having at least one peptide chain that binds a heparin-binding growth factor receptor, covalently bound to a hydrophobic linker, which is in turn covalently bound to a non-signaling peptide that includes a heparin-binding domain. The synthetic heparin-binding growth factor analogs are useful as soluble biologics or as surface coatings for medical devices.

Effect of Compressive Mode I on the Mixed Mode I/II Fatigue Crack Growth Rate of 42CrMo4

NASA Astrophysics Data System (ADS)

Heirani, Hasan; Farhangdoost, Khalil

2018-01-01

Subsurface cracks in mechanical contact loading components are subjected to mixed mode I/II, so it is necessary to evaluate the fatigue behavior of materials under mixed mode loading. For this purpose, fatigue crack propagation tests are performed with compact tension shear specimens for several stress intensity factor (SIF) ratios of mode I and mode II. The effect of compressive mode I loading on mixed mode I/II crack growth rate and fracture surface is investigated. Tests are carried out for the pure mode I, pure mode II, and two different mixed mode loading angles. On the basis of the experimental results, mixed mode crack growth rate parameters are proposed according to Tanaka and Richard with Paris' law. Results show neither Richard's nor Tanaka's equivalent SIFs are very useful because these SIFs depend strongly on the loading angle, but Richard's equivalent SIF formula is more suitable than Tanaka's formula. The compressive mode I causes the crack closure, and the friction force between the crack surfaces resists against the crack growth. In compressive loading with 45° angle, d a/d N increases as K eq decreases.

Fibroblast growth factor regulates insulin-like growth factor-binding protein production by vascular smooth muscle cells.

PubMed

Ververis, J; Ku, L; Delafontaine, P

1994-02-01

Insulin-like growth factor I is an important mitogen for vascular smooth muscle cells, and its effects are regulated by several binding proteins. Western ligand blotting of conditioned medium from rat aortic smooth muscle cells detected a 24 kDa binding protein and a 28 kDa glycosylated variant of this protein, consistent with insulin-like growth factor binding protein-4 by size. Low amounts of a glycosylated 38 to 42 kDa doublet (consistent with binding protein-3) and a 31 kDa non-glycosylated protein also were present. Basic fibroblast growth factor markedly increased secretion of the 24 kDa binding protein and its 28 kDa glycosylated variant. This effect was dose- and time-dependent and was inhibited by co-incubation with cycloheximide. Crosslinking of [125I]-insulin-like growth factor I to cell monolayers revealed no surface-associated binding proteins, either basally or after agonist treatment. Induction of binding protein production by fibroblast growth factor at sites of vascular injury may be important in vascular proliferative responses in vivo.

The Influence of Platelet-Derived Growth Factor and Fibroblast Growth Factor 2 on Oligodendrocyte Development and Remyelination

DTIC Science & Technology

2004-01-01

OLIGODENDROCYTE DEVELOPMENT AND REMYELINATION 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e...Z39-18 ABSTRACT Title: THE INFLUENCE OF PLATELET-DERIVED GROWTH FACTOR AND FIBROBLAST GROWTH FACTOR 2 ON OLIGODENDROCYTE DEVELOPMENT AND...GROWTH FACTOR 2 ON OLIGODENDROCYTE DEVELOPMENT AND REMYELINATION by Joshua C. Murtie Thesis/dissertation submitted to the

Efficient delivery of connective tissue growth factor shRNA using PAMAM nanoparticles.

PubMed

Huang, Z J; Yi, B; Yuan, H; Yang, G P

2014-08-28

The aim of this study was to detect the anti-fibrosis activity of connective tissue growth factor (CTGF) small hairpin RNA (shRNA) mediated by polyamidoamine dendrimer nanoparticles in rat myocardial cell lines and myocardium. CTGF shRNAs were constructed from inverted oligonucleotides and a polyamidoamine nanoparticle vector was used to transfer shRNA into H9c2 myocardial cells and spontaneously hypertensive rats. The expression of CTGF, transforming growth factor-b1, and laminin were measured by semi-quantitative reverse transcription-polymerase chain reaction, Western blotting, and immunohistochemistry. pCTGF-shRNA significantly reduced CTGF upregulation induced by angiotensin II in H9c2 myocardial cells. The mRNA and protein expression of CTGF and laminin in pCTGF-shRNA-transferred spontaneously hypertensive rats decreased significantly compared to the control group and pHK-shRNA group (P < 0.05). The expression of transforming growth factor-b1 showed no significant difference among the 3 groups (P > 0.05). pCTGF-shRNA mediated by polyamidoamine can be used to successfully reduce myocardial CTGF and laminin expression, suggesting that this system can be used to improve myocardial fibrosis therapy.

Insulin-Like Growth Factor I (IGF-1) Ec/Mechano Growth Factor – A Splice Variant of IGF-1 within the Growth Plate

PubMed Central

Schlegel, Werner; Raimann, Adalbert; Halbauer, Daniel; Scharmer, Daniela; Sagmeister, Susanne; Wessner, Barbara; Helmreich, Magdalena; Haeusler, Gabriele; Egerbacher, Monika

2013-01-01

Human insulin-like growth factor 1 Ec (IGF-1Ec), also called mechano growth factor (MGF), is a splice variant of insulin-like growth factor 1 (IGF-1), which has been shown in vitro as well as in vivo to induce growth and hypertrophy in mechanically stimulated or damaged muscle. Growth, hypertrophy and responses to mechanical stimulation are important reactions of cartilaginous tissues, especially those in growth plates. Therefore, we wanted to ascertain if MGF is expressed in growth plate cartilage and if it influences proliferation of chondrocytes, as it does in musculoskeletal tissues. MGF expression was analyzed in growth plate and control tissue samples from piglets aged 3 to 6 weeks. Furthermore, growth plate chondrocyte cell culture was used to evaluate the effects of the MGF peptide on proliferation. We showed that MGF is expressed in considerable amounts in the tissues evaluated. We found the MGF peptide to be primarily located in the cytoplasm, and in some instances, it was also found in the nucleus of the cells. Addition of MGF peptides was not associated with growth plate chondrocyte proliferation. PMID:24146828

Differential impact of diabetes mellitus type II and arterial hypertension on collateral artery growth and concomitant macrophage accumulation.

PubMed

Ito, Wulf D; Lund, Natalie; Sager, Hendrik; Becker, Wiebke; Wenzel, Ulrich

2015-01-01

Diabetes mellitus type II and arterial hypertension are major risk factors for peripheral arterial disease and have been considered to reduce collateral growth (arteriogenesis). Collateral growth proceeds through different stages. Vascular proliferation and macrophage accumulation are hallmarks of early collateral growth. We here compare the impact of arterial hypertension and diabetes mellitus type II on collateral proliferation (Brdu incorporation) and macrophage accumulation (ED 2 staining) as well as collateral vessel function (collateral conductance) in a rat model of peripheral vascular disease (femoral artery occlusion), diabetes mellitus type II (Zucker fatty diabetic rats and Zucker lean rat controls) and arterial hypertension (induced via clip placement around the right renal arteriy). We furthermore tested the impact of monocyte chemoattractant protein-1 (MCP‑1) on collateral proliferation and macrophage accumulation in these models Diabetic animals showed reduced vascular proliferation and macrophage accumulation, which however did not translate into a change of collateral conductance. Hypertensive animals on the contrary had reduced collateral conductances without altered macrophage accumulation and only a marginal reduction in collateral proliferation. Infusion of MCP‑1 only enhanced vascular proliferation in diabetic animals. These findings illustrate that impaired monocyte/macrophage recruitment is responsible for reduced collateral growth under diabetic conditions but not in arterial hypertension suggesting that diabetes mellitus in particular affects early stages of collateral growth whereas hypertension has its impact on later remodeling stages. Successful pro-arteriogenic treatment strategies in a patient population that presents with diabetes mellitus and arterial hypertension need to address different stages of collateral growth and thus different molecular and cellular targets simultaneously.

Serum from Chronic Hepatitis B Patients Promotes Growth and Proliferation via the IGF-II/IGF-IR/MEK/ERK Signaling Pathway in Hepatocellular Carcinoma Cells.

PubMed

Ji, Yuanyuan; Wang, Zhidong; Chen, Haiyan; Zhang, Lei; Zhuo, Fei; Yang, Qingqing

2018-05-09

Chronic hepatitis B virus (HBV) infection (CHB) plays a central role in the etiology of hepatocellular carcinoma (HCC). Emerging evidence implicates insulin-like growth factor (IGF)-II as a major risk factor for the growth and development of HCC. However, the relationship between HBV infection and IGF-II functions remains to be elucidated. Levels of circulating IGF-II and IGF-I receptor (IGF-IR) in healthy donors (HDs) and CHB patients were tested by ELISA. Human HCC cell lines (HepG-2, SMMC-7721, MHCC97-H) were incubated with serum from HDs and CHB patients at various concentrations for 24, 48, and 72 h. MTT and plate colony formation assays, BrdU ELISA, ELISA, small-interfering RNA (siRNA) transfection, quantitative real-time PCR, and western blot were applied to assess the functional and molecular mechanisms in HCC cell lines. Serum levels of IGF-II and IGF-IR were significantly higher in CHB patients than in HDs. Additionally, serum from CHB patients directly induced cell growth, proliferation, IGF-II secretion, and HDGF-related protein-2 (HRP-2) and nuclear protein 1 (NUPR1) mRNA and protein expression in HCC cells. Moreover, serum from CHB patients increased IGF-II-induced cell growth, proliferation, and HRP-2 and NUPR1 mRNA and protein expression in HCC cells. Blockade of IGF-IR clearly inhibited the above effects. Most importantly, interference with IGF-II function markedly repressed the cell proliferation and HRP-2 and NUPR1 mRNA and protein expression induced by serum from CHB patients. Furthermore, serum from CHB patients induced ERK phosphorylation via IGF-IR, with the MEK inhibitor PD98059 significantly decreasing CHB patient serum-induced IGF-II secretion, cell proliferation, and HRP-2 and NUPR1 mRNA and protein expression. Serum from CHB patients increases cell growth and proliferation and enhances HRP-2 and NUPR1 expression in HCC cells via the IGF-II/IGF-IR/MEK/ERK signaling pathway. These findings help to explain the molecular mechanisms

Reduction of relative centrifugation force within injectable platelet-rich-fibrin (PRF) concentrates advances patients' own inflammatory cells, platelets and growth factors: the first introduction to the low speed centrifugation concept.

PubMed

Choukroun, J; Ghanaati, S

2018-02-01

The aim of this study was to analyze systematically the influence of the relative centrifugation force (RCF) on leukocytes, platelets and growth factor release within fluid platelet-rich fibrin matrices (PRF). Systematically using peripheral blood from six healthy volunteers, the RCF was reduced four times for each of the three experimental protocols (I-III) within the spectrum (710-44 g), while maintaining a constant centrifugation time. Flow cytometry was applied to determine the platelets and leukocyte number. The growth factor concentration was quantified 1 and 24 h after clotting using ELISA. Reducing RCF in accordance with protocol-II (177 g) led to a significantly higher platelets and leukocytes numbers compared to protocol-I (710 g). Protocol-III (44 g) showed a highly significant increase of leukocytes and platelets number in comparison to -I and -II. The growth factors' concentration of VEGF and TGF-β1 was significantly higher in protocol-II compared to -I, whereas protocol-III exhibited significantly higher growth factor concentration compared to protocols-I and -II. These findings were observed among 1 and 24 h after clotting, as well as the accumulated growth factor concentration over 24 h. Based on the results, it has been demonstrated that it is possible to enrich PRF-based fluid matrices with leukocytes, platelets and growth factors by means of a single alteration of the centrifugation settings within the clinical routine. We postulate that the so-called low speed centrifugation concept (LSCC) selectively enriches leukocytes, platelets and growth factors within fluid PRF-based matrices. Further studies are needed to evaluate the effect of cell and growth factor enrichment on wound healing and tissue regeneration while comparing blood concentrates gained by high and low RCF.

Growth factor transgenes interactively regulate articular chondrocytes.

PubMed

Shi, Shuiliang; Mercer, Scott; Eckert, George J; Trippel, Stephen B

2013-04-01

Adult articular chondrocytes lack an effective repair response to correct damage from injury or osteoarthritis. Polypeptide growth factors that stimulate articular chondrocyte proliferation and cartilage matrix synthesis may augment this response. Gene transfer is a promising approach to delivering such factors. Multiple growth factor genes regulate these cell functions, but multiple growth factor gene transfer remains unexplored. We tested the hypothesis that multiple growth factor gene transfer selectively modulates articular chondrocyte proliferation and matrix synthesis. We tested the hypothesis by delivering combinations of the transgenes encoding insulin-like growth factor I (IGF-I), fibroblast growth factor-2 (FGF-2), transforming growth factor beta1 (TGF-β1), bone morphogenetic protein-2 (BMP-2), and bone morphogenetic protien-7 (BMP-7) to articular chondrocytes and measured changes in the production of DNA, glycosaminoglycan, and collagen. The transgenes differentially regulated all these chondrocyte activities. In concert, the transgenes interacted to generate widely divergent responses from the cells. These interactions ranged from inhibitory to synergistic. The transgene pair encoding IGF-I and FGF-2 maximized cell proliferation. The three-transgene group encoding IGF-I, BMP-2, and BMP-7 maximized matrix production and also optimized the balance between cell proliferation and matrix production. These data demonstrate an approach to articular chondrocyte regulation that may be tailored to stimulate specific cell functions, and suggest that certain growth factor gene combinations have potential value for cell-based articular cartilage repair. Copyright © 2012 Wiley Periodicals, Inc.

Slow crack growth in glass in combined mode I and mode II loading

NASA Technical Reports Server (NTRS)

Shetty, D. K.; Rosenfield, A. R.

1991-01-01

Slow crack growth in soda-lime glass under combined mode I and mode II loading was investigated in precracked disk specimens in which pure mode I, pure mode II, and various combinations of mode I and mode II were achieved by loading in diametral compression at selected angles with respect to symmetric radial cracks. It is shown that slow crack growth under these conditions can be described by a simple exponential relationship with elastic strain energy release rate as the effective crack-driving force parameter. It is possible to interpret this equation in terms of theoretical models that treat subcritical crack growth as a thermally activated bond-rupture process with an activation energy dependent on the environment, and the elastic energy release rate as the crack-driving force parameter.

Reduced growth factor requirement of keloid-derived fibroblasts may account for tumor growth

DOE Office of Scientific and Technical Information (OSTI.GOV)

Russell, S.B.; Trupin, K.M.; Rodriguez-Eaton, S.

Keloids are benign dermal tumors that form during an abnormal wound-healing process is genetically susceptible individuals. Although growth of normal and keloid cells did not differ in medium containing 10% (vol/vol) fetal bovine serum, keloid culture grew to significantly higher densities than normal cells in medium containing 5% (vol/vol) fetal bovine serum, keloid cultures grew to significantly higher densities than normal cells in medium containing 5% (vol/vol) plasma or 1% fetal bovine serum. Conditioned medium from keloid cultures did not stimulate growth of normal cells in plasma nor did it contain detectable platelet-derived growth factor or epidermal growth factor. Keloidmore » fibroblasts responded differently than normal adult fibroblasts to transforming growth factor ..beta... Whereas transforming growth factor ..beta.. reduced growth stimulation by epidermal growth factor in cells from normal adult skin or scars, it enhanced the activity of epidermal growth factor in cells from normal adult skin or scars, it enhanced the activity of epidermal growth factor in cells from keloids. Normal and keloid fibroblasts also responded differently to hydrocortisone: growth was stimulated in normal adult cells and unaffected or inhibited in keloid cells. Fetal fibroblasts resembled keloid cells in their ability to grow in plasma and in their response to hydrocortisone. The ability of keloid fibroblasts to grow to higher cell densities in low-serum medium than cells from normal adult skin or from normal early or mature scars suggests that a reduced dependence on serum growth factors may account for their prolonged growth in vivo. Similarities between keloid and fetal cells suggest that keloids may result from the untimely expression of growth-control mechanism that is developmentally regulated.« less

Calcium/calmodulin-dependent protein kinase II activity regulates the proliferative potential of growth plate chondrocytes.

PubMed

Li, Yuwei; Ahrens, Molly J; Wu, Amy; Liu, Jennifer; Dudley, Andrew T

2011-01-01

For tissues that develop throughout embryogenesis and into postnatal life, the generation of differentiated cells to promote tissue growth is at odds with the requirement to maintain the stem cell/progenitor cell population to preserve future growth potential. In the growth plate cartilage, this balance is achieved in part by establishing a proliferative phase that amplifies the number of progenitor cells prior to terminal differentiation into hypertrophic chondrocytes. Here, we show that endogenous calcium/calmodulin-dependent protein kinase II (CamkII, also known as Camk2) activity is upregulated prior to hypertrophy and that loss of CamkII function substantially blocks the transition from proliferation to hypertrophy. Wnt signaling and Pthrp-induced phosphatase activity negatively regulate CamkII activity. Release of this repression results in activation of multiple effector pathways, including Runx2- and β-catenin-dependent pathways. We present an integrated model for the regulation of proliferation potential by CamkII activity that has important implications for studies of growth control and adult progenitor/stem cell populations.

Comparative effects of contraction and angiotensin II on growth of adult feline cardiocytes in primary culture

NASA Technical Reports Server (NTRS)

Wada, H.; Zile, M. R.; Ivester, C. T.; Cooper, G. 4th; McDermott, P. J.

1996-01-01

The purposes of this study were 1) to determine whether angiotensin II causes growth of adult feline cardiocytes in long-term culture, 2) to compare the growth effects of angiotensin II with those resulting from electrically stimulated contraction, and 3) to determine whether the anabolic effects of contraction are exerted via the angiotensin type 1 receptor. Adult feline cardiocytes were cultured on laminin-coated trays in a serum-free medium. Cardiocytes were either electrically stimulated to contract (1 Hz, 5-ms pulse duration, alternating polarity) or were nonstimulated and quiescent. Quiescent cells were studied as controls and after treatment with angiotensin II (10(-8) M), losartan (10(-6) M; an angiotensin type 1-receptor antagonist), or angiotensin II plus losartan. Contracting cells were studied in the presence and absence of angiotensin II or losartan. In quiescent cardiocytes, angiotensin II treatment on day 7 significantly increased protein synthesis rates by 22% and protein content per cell by 17%. The effects of angiotensin II were completely blocked by losartan. Electrically stimulated contraction on days 4 and 7 in culture significantly increased protein synthesis rate by 18 and 38% and protein content per cell by 19 and 46%, respectively. Angiotensin II treatment did not further increase protein synthesis rate or protein content in contracting cardiocytes. Furthermore, losartan did not block the anabolic effects of contraction on protein synthesis rates or protein content. In conclusion, angiotensin II can exert a modest anabolic effect on adult feline cardiocytes in culture. In contracting feline cardiocytes, angiotensin II has no effect on growth. Growth caused by electrically stimulated contraction occurs more rapidly and is greater in magnitude than that caused by angiotensin II. Growth of contracting adult feline cardiocytes is not dependent on activation of the angiotensin receptor.

Growth factors, nutrient signaling, and cardiovascular aging

PubMed Central

Fontana, Luigi; Vinciguerra, Manlio; Longo, Valter D.

2012-01-01

Growth factors regulated by specific macronutrients have been shown to promote aging and accelerate mortality in the great majority of the organisms studied. In particular, the enzymes activated by growth hormone (GH), insulin and insulin-like growth factor 1 (IGF-I) in mammals and their orthologs in simple model organisms represent perhaps the best-understood proteins involved in the aging process. Dietary restriction (DR), which reduces the level of IGF-I and of other growth factors, has been associated with protection from diabetes, cancer, and cardiovascular diseases and deficiencies in GH signaling and IGF-I are strongly associated with protection from cancer and diabetes in both mice and humans, but their role in cardiac function and cardiovascular diseases is controversial. Here we review the link between growth factors, cardiac function and heart disease with focus on the cardioprotective and sensitizing effect of growth factors in both model organisms and humans. PMID:22499903

Roles of insulin-like growth factors in metamorphic development of turbot (Scophthalmus maximus).

PubMed

Jia, Yudong

2018-01-31

Larval turbot (Scophthalmus maximus) undergo metamorphosis, a late post-embryonic developmental event that precedes juvenile transition. Insulin-like growth factors (IGFs) are important endocrine/autocrine/paracrine factors that provide essential signals to control of the embryonic and postnatal development of vertebrate species, including fish. Accumulating evidence suggests that IGFs are involved in regulating the metamorphic development of flatfish. This mini review focus on the functions of all known IGFs (IGF-I and IGF-II) during the metamorphic development of turbot. Information about IGFs and insulin-like growth factors binding proteins (IGFBPs) from other teleosts is also included in this review to provide an overview of IGFs functions in the metamorphic development of turbot. These findings may enhance our understanding of the potential roles of the IGFs system in controlling of flatfish metamorphosis and contributing to the improvement of broodstock management strategies for larval turbot. Copyright © 2018 Elsevier Inc. All rights reserved.

Signal transduction by beta1 integrin receptors in human chondrocytes in vitro: collaboration with the insulin-like growth factor-I receptor.

PubMed

Shakibaei, M; John, T; De Souza, P; Rahmanzadeh, R; Merker, H J

1999-09-15

We have examined the mechanism by which collagen-binding integrins co-operate with insulin-like growth factor-I (IGF-I) receptors (IGF-IR) to regulate chondrocyte phenotype and differentiation. Adhesion of chondrocytes to anti-beta1 integrin antibodies or collagen type II leads to phosphorylation of cytoskeletal and signalling proteins localized at focal adhesions, including alpha-actinin, vinculin, paxillin and focal adhesion kinase (FAK). These stimulate docking proteins such as Shc (Src-homology collagen). Moreover, exposure of collagen type II-cultured chondrocytes to IGF-I leads to co-immunoprecipitation of Shc protein with the IGF-IR and with beta1, alpha1 and alpha5 integrins, but not with alpha3 integrin. Shc then associates with growth factor receptor-bound protein 2 (Grb2), an adaptor protein and extracellular signal-regulated kinase. The expression of the docking protein Shc occurs only when chondrocytes are bound to collagen type II or integrin antibodies and increases when IGF-I is added, suggesting a collaboration between integrins and growth factors in a common/shared biochemical signalling pathway. Furthermore, these results indicate that focal adhesion assembly may facilitate signalling via Shc, a potential common target for signal integration between integrin and growth-factor signalling regulatory pathways. Thus, the collagen-binding integrins and IGF-IR co-operate to regulate focal adhesion components and these signalling pathways have common targets (Shc-Grb2 complex) in subcellular compartments, thereby linking to the Ras-mitogen-activated protein kinase signalling pathway. These events may play a role during chondrocyte differentiation.

Role of epidermal growth factor and transforming growth factor α in the developing stomach

PubMed Central

Kelly, E; Newell, S; Brownlee, K; Farmery, S; Cullinane, C; Reid, W; Jackson, P; Gray, S; Primrose, J; Lagopoulos, M

1997-01-01

AIMS—To determine whether epidermal growth factor (EGF) or the related transforming growth factor α (TGFα) may have a role in the developing human stomach; to substantiate the presence of EGF in human liquor in the non-stressed infant and whether EGF in amniotic fluid is maternally or fetally derived.
METHODS—The temporal expression and localisation of EGF, TGFα, and their receptors during fetal and neonatal life were examined in 20 fetal and five infant stomachs. Simultaneously, samples of amniotic fluid and fetal urine from 10 newborn infants were collected and assayed for EGF by radioimmunoassay.
RESULTS—EGF immunoreactivity was not noted in any of the specimens examined. In contrast, TGFα immunoreactivity was shown in mucous cells from 18 weeks of gestation onwards. EGF receptor immunoreactivity was seen on superficial mucous cells in gastric mucosa from 18 weeks of gestation onwards. The median concentration of EGF was 30 and 8.5 pg/ml in amniotic fluid and fetal urine, respectively, suggesting that EGF is not produced by the fetus.
CONCLUSIONS—This study adds weight to the hypothesis that swallowed EGF, probably produced by the amniotic membranes, and locally produced TGFα, may have a role in the growth and maturation of the human stomach.

 Keywords: epidermal growth factor; transforming growth factor α; EGF receptors; stomach PMID:9175944

[Relationship between the expression levels of PAPP-A metalloproteinase and growth and transcriptional factors in endometrial cancer].

PubMed

Iunusova, N V; Spirina, L V; Kondakova, L A; Kolomiets, A L; Chernyshova, A L; Koval', V D; Nedosekov, V V; Savenkova, O V

2013-01-01

We have examined for the first time the relationship between the expression of PAPP-A metalloproteinase and insulin-like growth factors (IGF-I, IGF-II, VEGF) and transcription factors (NF-kappaB, HIF-1) playing an important role in pathogenesis of cancer. We also demonstrated a positive association between the level of PAPP-A metalloproteinase and the level of growth (VEGF and IGF-I) and transcription factors (NF-kappaB p50, NF-kappaB p65, HIF-1alpha). The current findings suggest an important role of PAPP-A in regulation of bioavailability of IGF-I, VEGF, activated forms of NF-kappaB, and alpha-subunits of HIF-1 in endometrial tumors.

Astrocyte transforming growth factor beta 1 promotes inhibitory synapse formation via CaM kinase II signaling.

PubMed

Diniz, Luan Pereira; Tortelli, Vanessa; Garcia, Matheus Nunes; Araújo, Ana Paula Bérgamo; Melo, Helen M; Silva, Gisele S Seixas da; Felice, Fernanda G De; Alves-Leon, Soniza Vieira; Souza, Jorge Marcondes de; Romão, Luciana Ferreira; Castro, Newton Gonçalves; Gomes, Flávia Carvalho Alcantara

2014-12-01

The balance between excitatory and inhibitory synaptic inputs is critical for the control of brain function. Astrocytes play important role in the development and maintenance of neuronal circuitry. Whereas astrocytes-derived molecules involved in excitatory synapses are recognized, molecules and molecular mechanisms underlying astrocyte-induced inhibitory synapses remain unknown. Here, we identified transforming growth factor beta 1 (TGF-β1), derived from human and murine astrocytes, as regulator of inhibitory synapse in vitro and in vivo. Conditioned media derived from human and murine astrocytes induce inhibitory synapse formation in cerebral cortex neurons, an event inhibited by pharmacologic and genetic manipulation of the TGF-β pathway. TGF-β1-induction of inhibitory synapse depends on glutamatergic activity and activation of CaM kinase II, which thus induces localization and cluster formation of the synaptic adhesion protein, Neuroligin 2, in inhibitory postsynaptic terminals. Additionally, intraventricular injection of TGF-β1 enhanced inhibitory synapse number in the cerebral cortex. Our results identify TGF-β1/CaMKII pathway as a novel molecular mechanism underlying astrocyte control of inhibitory synapse formation. We propose here that the balance between excitatory and inhibitory inputs might be provided by astrocyte signals, at least partly achieved via TGF-β1 downstream pathways. Our work contributes to the understanding of the GABAergic synapse formation and may be of relevance to further the current knowledge on the mechanisms underlying the development of various neurological disorders, which commonly involve impairment of inhibitory synapse transmission. © 2014 Wiley Periodicals, Inc.

Epidermal growth factor-like growth factors prevent apoptosis of alcohol-exposed human placental cytotrophoblast cells.

PubMed

Wolff, Garen S; Chiang, Po Jen; Smith, Susan M; Romero, Roberto; Armant, D Randall

2007-07-01

Maternal alcohol abuse during pregnancy can produce an array of birth defects comprising fetal alcohol syndrome. A hallmark of fetal alcohol syndrome is intrauterine growth retardation, which is associated with elevated apoptosis of placental cytotrophoblast cells. Using a human first trimester cytotrophoblast cell line, we examined the relationship between exposure to ethanol and cytotrophoblast survival, as well as the ameliorating effects of epidermal growth factor (EGF)-like growth factors produced by human cytotrophoblast cells. After exposure to 0-100 mM ethanol, cell death was quantified by the TUNEL method, and expression of the nuclear proliferation marker, Ki67, was measured by immunohistochemistry. The mode of cell death was determined by assessing annexin V binding, caspase 3 activation, pyknotic nuclear morphology, reduction of TUNEL by caspase inhibition, and cellular release of lactate dehydrogenase. Ethanol significantly reduced proliferation and increased cell death approximately 2.5-fold through the apoptotic pathway within 1-2 h of exposure to 50 mM alcohol. Exposure to 25-50 mM ethanol significantly increased transforming growth factor alpha (TGFA) and heparin-binding EGF-like growth factor (HBEGF), but not EGF or amphiregulin (AREG). When cytotrophoblasts were exposed concurrently to 100 mM ethanol and 1 nM HBEGF or TGFA, the increase in apoptosis was prevented, while EGF ameliorated at 10 nM and AREG was weakly effective. HBEGF survival-promoting activity required ligation of either of its cognate receptors, HER1 or HER4. These findings reveal the potential for ethanol to rapidly induce cytotrophoblast apoptosis. However, survival factor induction could provide cytotrophoblasts with an endogenous cytoprotective mechanism.

Association of growth factors, HIF-1 and NF-κB expression with proteasomes in endometrial cancer.

PubMed

Spirina, Ludmila V; Yunusova, Nataliya V; Kondakova, Irina V; Kolomiets, Larisa A; Koval, Valeriya D; Chernyshova, Alena L; Shpileva, Olga V

2012-09-01

Insulin-like growth factors (IGFs), vascular endothelial growth factor (VEGF), hypoxia-inducible factor-1 (HIF-1), and nuclear factor kappa-B (NF-κB) are known to play an important role in endometrial cancer pathogenesis. However, the proteolytic regulation of these factors is still poorly understood. We studied the correlation between chymotrypsin-like activity of proteasomes and IGF-I, IGF-II, VEGF, HIF-1, and NF-κB levels in endometrial cancer tissues. It was shown that the total activity of proteasomes and the activity of the 20S and 26S proteasomes in malignant tumors were significantly higher than those observed in the normal endometrium. Negative relationships between the proteasome activity and IGF-I, HIF-1, and NF-κB p50 expressions were found. High 20S proteasome activity was associated with increase of HIF-1 level. Positive relationships between IGF-I expression and two classic forms of NF-κB p50 and p65 in endometrial cancer were revealed. The data obtained indicate the possible proteasomal regulation of growth and transcription factors. The major pool of IGF-I is located in the extracellular space, and it is likely that extracellular proteasomes also take part in the regulation of the IGF-I content. The present data show the evidence of proteasome regulation of growth and nuclear factors that can play an important role in cancer pathogenesis.

Structural analysis of the human fibroblast growth factor receptor 4 kinase.

PubMed

Lesca, E; Lammens, A; Huber, R; Augustin, M

2014-11-11

The family of fibroblast growth factor receptors (FGFRs) plays an important and well-characterized role in a variety of pathological disorders. FGFR4 is involved in myogenesis and muscle regeneration. Mutations affecting the kinase domain of FGFR4 may cause cancer, for example, breast cancer or rhabdomyosarcoma. Whereas FGFR1-FGFR3 have been structurally characterized, the structure of the FGFR4 kinase domain has not yet been reported. In this study, we present four structures of the kinase domain of FGFR4, in its apo-form and in complex with different types of small-molecule inhibitors. The two apo-FGFR4 kinase domain structures show an activation segment similar in conformation to an autoinhibitory segment observed in the hepatocyte growth factor receptor kinase but different from the known structures of other FGFR kinases. The structures of FGFR4 in complex with the type I inhibitor Dovitinib and the type II inhibitor Ponatinib reveal the molecular interactions with different types of kinase inhibitors and may assist in the design and development of FGFR4 inhibitors. Copyright © 2014 Elsevier Ltd. All rights reserved.

Growth factor and pro-inflammatory cytokine contents in platelet-rich plasma (PRP), plasma rich in growth factors (PRGF), advanced platelet-rich fibrin (A-PRF), and concentrated growth factors (CGF).

PubMed

Masuki, Hideo; Okudera, Toshimitsu; Watanebe, Taisuke; Suzuki, Masashi; Nishiyama, Kazuhiko; Okudera, Hajime; Nakata, Koh; Uematsu, Kohya; Su, Chen-Yao; Kawase, Tomoyuki

2016-12-01

The development of platelet-rich fibrin (PRF) drastically simplified the preparation procedure of platelet-concentrated biomaterials, such as platelet-rich plasma (PRP), and facilitated their clinical application. PRF's clinical effectiveness has often been demonstrated in pre-clinical and clinical studies; however, it is still controversial whether growth factors are significantly concentrated in PRF preparations to facilitate wound healing and tissue regeneration. To address this matter, we performed a comparative study of growth factor contents in PRP and its derivatives, such as advanced PRF (A-PRF) and concentrated growth factors (CGF). PRP and its derivatives were prepared from the same peripheral blood samples collected from healthy donors. A-PRF and CGF preparations were homogenized and centrifuged to produce extracts. Platelet and white blood cell counts in A-PRF and CGF preparations were determined by subtracting those counts in red blood cell fractions, supernatant acellular serum fractions, and A-PRF/CGF exudate fractions from those counts of whole blood samples. Concentrations of growth factors (TGF-β1, PDGF-BB, VEGF) and pro-inflammatory cytokines (IL-1β, IL-6) were determined using ELISA kits. Compared to PRP preparations, both A-PRF and CGF extracts contained compatible or higher levels of platelets and platelet-derived growth factors. In a cell proliferation assay, both A-PRF and CGF extracts significantly stimulated the proliferation of human periosteal cells without significant reduction at higher doses. These data clearly demonstrate that both A-PRF and CGF preparations contain significant amounts of growth factors capable of stimulating periosteal cell proliferation, suggesting that A-PRF and CGF preparations function not only as a scaffolding material but also as a reservoir to deliver certain growth factors at the site of application.

Growth factors, muscle function, and doping.

PubMed

Goldspink, Geoffrey; Wessner, Barbara; Tschan, Harald; Bachl, Norbert

2010-03-01

This article discusses the inevitable use of growth factors for enhancing muscle strength and athletic performance. Much effort has been expended on developing a treatment of muscle wasting associated with a range of diseases and aging. Frailty in the aging population is a major socioeconomic and medical problem. Emerging molecular techniques have made it possible to gain a better understanding of the growth factor genes and how they are activated by physical activity. The ways that misuse of growth factors may be detected and verified in athletes and future challenges for detecting manipulation of signaling pathways are discussed. Copyright 2010. Published by Elsevier Inc.

Role of G protein-coupled estrogen receptor-1, matrix metalloproteinases 2 and 9, and heparin binding epidermal growth factor-like growth factor in estradiol-17β-stimulated bovine satellite cell proliferation.

PubMed

Kamanga-Sollo, E; Thornton, K J; White, M E; Dayton, W R

2014-10-01

In feedlot steers, estradiol-17β (E2) and combined E2 and trenbolone acetate (a testosterone analog) implants enhance rate and efficiency of muscle growth; and, consequently, these compounds are widely used as growth promoters. Although the positive effects of E2 on rate and efficiency of bovine muscle growth are well established, the mechanisms involved in these effects are not well understood. Combined E2 and trenbolone acetate implants result in significantly increased muscle satellite cell number in feedlot steers. Additionally, E2 treatment stimulates proliferation of cultured bovine satellite cells (BSC). Studies in nonmuscle cells have shown that binding of E2 to G protein-coupled estrogen receptor (GPER)-1 results in activation of matrix metalloproteinases 2 and 9 (MMP2/9) resulting in proteolytic release of heparin binding epidermal growth factor-like growth factor (hbEGF) from the cell surface. Released hbEGF binds to and activates the epidermal growth factor receptor resulting in increased proliferation. To assess if GPER-1, MMP2/9, and/or hbEGF are involved in the mechanism of E2-stimulated BSC proliferation, we have examined the effects of G36 (a specific inhibitor of GPER-1), CRM197 (a specific inhibitor of hbEGF), and MMP-2/MMP-9 Inhibitor II (an inhibitor of MMP2/9 activity) on E2-stimulated BSC proliferation. Inhibition of GPER-1, MMP2/9, or hbEGF suppresses E2-stimulated BSC proliferation (P < 0.001) suggesting that all these are required in order for E2 to stimulate BSC proliferation. These results strongly suggest that E2 may stimulate BSC proliferation by binding to GPER-1 resulting in MMP2/9-catalyzed release of cell membrane-bound hbEGF and subsequent activation of epidermal growth factor receptor by binding of released hbEGF. Copyright © 2014 Elsevier Inc. All rights reserved.

Insulin-Like Growth Factor Receptor Signaling is Necessary for Epidermal Growth Factor Mediated Proliferation of SVZ Neural Precursors in vitro Following Neonatal Hypoxia–Ischemia

PubMed Central

Alagappan, Dhivyaa; Ziegler, Amber N.; Chidambaram, Shravanthi; Min, Jungsoo; Wood, Teresa L.; Levison, Steven W.

2014-01-01

In this study, we assessed the importance of insulin-like growth factor (IGF) and epidermal growth factor (EGF) receptor co-signaling for rat neural precursor (NP) cell proliferation and self-renewal in the context of a developmental brain injury that is associated with cerebral palsy. Consistent with previous studies, we found that there is an increase in the in vitro growth of subventricular zone NPs isolated acutely after cerebral hypoxia–ischemia; however, when cultured in medium that is insufficient to stimulate the IGF type 1 receptor, neurosphere formation and the proliferative capacity of those NPs was severely curtailed. This reduced growth capacity could not be attributed simply to failure to survive. The growth and self-renewal of the NPs could be restored by addition of both IGF-I and IGF-II. Since the size of the neurosphere is predominantly due to cell proliferation we hypothesized that the IGFs were regulating progression through the cell cycle. Analyses of cell cycle progression revealed that IGF-1R activation together with EGFR co-signaling decreased the percentage of cells in G1 and enhanced cell progression into S and G2. This was accompanied by increases in expression of cyclin D1, phosphorylated histone 3, and phosphorylated Rb. Based on these data, we conclude that coordinate signaling between the EGF receptor and the IGF type 1 receptor is necessary for the normal proliferation of NPs as well as for their reactive expansion after injury. These data indicate that manipulations that maintain or amplify IGF signaling in the brain during recovery from developmental brain injuries will enhance the production of new brain cells to improve neurological function in children who are at risk for developing cerebral palsy. PMID:24904523

Advancing osteochondral tissue engineering: bone morphogenetic protein, transforming growth factor, and fibroblast growth factor signaling drive ordered differentiation of periosteal cells resulting in stable cartilage and bone formation in vivo.

PubMed

Mendes, L F; Katagiri, H; Tam, W L; Chai, Y C; Geris, L; Roberts, S J; Luyten, F P

2018-02-21

Chondrogenic mesenchymal stem cells (MSCs) have not yet been used to address the clinical demands of large osteochondral joint surface defects. In this study, self-assembling tissue intermediates (TIs) derived from human periosteum-derived stem/progenitor cells (hPDCs) were generated and validated for stable cartilage formation in vivo using two different animal models. hPDCs were aggregated and cultured in the presence of a novel growth factor (GF) cocktail comprising of transforming growth factor (TGF)-β1, bone morphogenetic protein (BMP)2, growth differentiation factor (GDF)5, BMP6, and fibroblast growth factor (FGF)2. Quantitative polymerase chain reaction (PCR) and immunohistochemistry were used to study in vitro differentiation. Aggregates were then implanted ectopically in nude mice and orthotopically in critical-size osteochondral defects in nude rats and evaluated by microcomputed tomography (µCT) and immunohistochemistry. Gene expression analysis after 28 days of in vitro culture revealed the expression of early and late chondrogenic markers and a significant upregulation of NOGGIN as compared to human articular chondrocytes (hACs). Histological examination revealed a bilayered structure comprising of chondrocytes at different stages of maturity. Ectopically, TIs generated both bone and mineralized cartilage at 8 weeks after implantation. Osteochondral defects treated with TIs displayed glycosaminoglycan (GAG) production, type-II collagen, and lubricin expression. Immunostaining for human nuclei protein suggested that hPDCs contributed to both subchondral bone and articular cartilage repair. Our data indicate that in vitro derived osteochondral-like tissues can be generated from hPDCs, which are capable of producing bone and cartilage ectopically and behave orthotopically as osteochondral units.

Placenta growth factor not vascular endothelial growth factor A or C can predict the early recurrence after radical resection of hepatocellular carcinoma.

PubMed

Ho, Ming-Chih; Chen, Chiung-Nien; Lee, Hsinyu; Hsieh, Fon-Jou; Shun, Chia-Tung; Chang, Chi-Lun; Lai, Yeun-Tyng; Lee, Po-Huang

2007-06-08

The purpose of this study was to evaluate the relationship between the expression of PlGF in tumor tissue and clinical outcomes in HCC patients. Tumor PlGF and vascular endothelial growth factor (VEGF)-A and VEGF-C mRNA were analyzed. Results demonstrated that patients with PlGF expression levels higher than median tended to have early recurrence compared to patients with PlGF expression lower than median (P=.031). In patients with AJCC stage II-III disease, this difference was even more significant (P=.002). In contrast, VEGF-A and VEGF-C could not predict early recurrence-free survival. Since PlGF expression correlated with early recurrence of HCC, PlGF may be an important prognostic indicator in HCC.

Growth factors and chronic wound healing: past, present, and future.

PubMed

Goldman, Robert

2004-01-01

Growth substances (cytokines and growth factors) are soluble signaling proteins affecting the process of normal wound healing. Cytokines govern the inflammatory phase that clears cellular and extracellular matrix debris. Wound repair is controlled by growth factors (platelet-derived growth factor [PDGF], keratinocyte growth factor, and transforming growth factor beta). Endogenous growth factors communicate across the dermal-epidermal interface. PDGF is important for most phases of wound healing. Becaplermin (PDGF-BB), the only growth factor approved by the Food and Drug Administration, requires daily application for neuropathic wound healing. Gene therapy is under development for more efficient growth factor delivery; a single application will induce constitutive growth factor expression for weeks. Based on dramatic preclinical animal studies, a phase 1 clinical trial planned on a PDGF genetic construct appears promising.

Predictive factors for intrauterine growth restriction

PubMed Central

Albu, AR; Anca, AF; Horhoianu, VV; Horhoianu, IA

2014-01-01

Abstract Reduced fetal growth is seen in about 10% of the pregnancies but only a minority has a pathological background and is known as intrauterine growth restriction or fetal growth restriction (IUGR / FGR). Increased fetal and neonatal mortality and morbidity as well as adult pathologic conditions are often associated to IUGR. Risk factors for IUGR are easy to assess but have poor predictive value. For the diagnostic purpose, biochemical serum markers, ultrasound and Doppler study of uterine and spiral arteries, placental volume and vascularization, first trimester growth pattern are object of assessment today. Modern evaluations propose combined algorithms using these strategies, all with the goal of a better prediction of risk pregnancies. Abbreviations: SGA = small for gestational age; IUGR = intrauterine growth restriction; FGR = fetal growth restriction; IUFD = intrauterine fetal demise; HIV = human immunodeficiency virus; PAPP-A = pregnancy associated plasmatic protein A; β-hCG = beta human chorionic gonadotropin; MoM = multiple of median; ADAM-12 = A-disintegrin and metalloprotease 12; PP-13 = placental protein 13; VEGF = vascular endothelial growth factor; PlGF = placental growth factor; sFlt-1 = soluble fms-like tyrosine kinase-1; UAD = uterine arteries Doppler ultrasound; RI = resistence index; PI = pulsatility index; VOCAL = Virtual Organ Computer–Aided Analysis software; VI = vascularization index; FI = flow index; VFI = vascularization flow index; PQ = placental quotient PMID:25408721

Growth factors and growth factor receptors in the hippocampus. Role in plasticity and response to injury.

PubMed

Nieto-Sampedro, M; Bovolenta, P

1990-01-01

Various growth factors are present in the hippocampal formation and appear responsible for the prominent plasticity of this brain area. Although hormone-like growth-promoting polypeptides are the best known, recent studies emphasize the importance in the growth response of molecules such as laminin proteoglycans, neurotransmitters and growth inhibitors. The progress and problems in the study of these substances are reviewed.

Engineering growth factors for regenerative medicine applications.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mitchell, Aaron C.; Briquez, Priscilla S.; Hubbell, Jeffrey A.

Growth factors are important morphogenetic proteins that instruct cell behavior and guide tissue repair and renewal. Although their therapeutic potential holds great promise in regenerative medicine applications, translation of growth factors into clinical treatments has been hindered by limitations including poor protein stability, low recombinant expression yield, and suboptimal efficacy. This review highlights current tools, technologies, and approaches to design integrated and effective growth factor-based therapies for regenerative medicine applications. The first section describes rational and combinatorial protein engineering approaches that have been utilized to improve growth factor stability, expression yield, biodistribution, and serum half-life, or alter their cell traffickingmore » behavior or receptor binding affinity. The second section highlights elegant biomaterial-based systems, inspired by the natural extracellular matrix milieu, that have been developed for effective spatial and temporal delivery of growth factors to cell surface receptors. Although appearing distinct, these two approaches are highly complementary and involve principles of molecular design and engineering to be considered in parallel when developing optimal materials for clinical applications.« less

Effects of heparin-binding epidermal growth factor-like growth factor on cell repopulation and signal transduction in periodontal ligament cells after scratch wounding in vitro.

PubMed

Lee, J S; Kim, J M; Hong, E K; Kim, S-O; Yoo, Y-J; Cha, J-H

2009-02-01

A growing amount of attention has been placed on periodontal regeneration and wound healing for periodontal therapy. This study was conducted in an effort to determine the effects of heparin-binding epidermal growth factor-like growth factor on cell repopulation and signal transduction in periodontal ligament cells after scratch wounding in vitro. Human periodontal ligament cells were acquired from explant tissue of human healthy periodontal ligament. After the wounding of periodontal ligament cells, the change in expression of heparin-binding epidermal growth factor-like growth factor and epidermal growth factor receptors 1-4 mRNA was assessed. The effects of heparin-binding epidermal growth factor-like growth factor on periodontal ligament cell proliferation and repopulation were assessed in vitro via the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and by photographing the injuries, respectively. Extracellular signal-regulated kinase (Erk)1/2, p38 and Akt phosphorylation was characterized via western blotting. Scratch wounding resulted in a significant up-regulation of heparin-binding epidermal growth factor-like growth factor mRNA expression, whereas wounding had no effect on the expression levels of epidermal growth factor receptors 1-4. Interestingly, no expression of epidermal growth factor receptors 2 and 4 was detectable prior to or after wounding. Heparin-binding epidermal growth factor-like growth factor treatment promoted the proliferation and repopulation of periodontal ligament cells. The scratch wounding also stimulated the phosphorylation of Erk1/2 and p38, but not of Akt, in periodontal ligament cells, and heparin-binding epidermal growth factor-like growth factor treatment applied after wounding amplified and extended the activations of Erk1/2 and p38, but not of Akt. Furthermore, Erk1/2 inhibition blocked the process of cell repopulation induced by heparin-binding epidermal growth factor-like growth factor, whereas the

Growth factor involvement in tension-induced skeletal muscle growth

NASA Technical Reports Server (NTRS)

Vandenburgh, H. H.

1987-01-01

Muscle tissue culture techniques were developed to grow skeletal myofibers which differentiate into more adult-like myofibers. Mechanical simulation studies of these muscle cells in a newly developed mechanical cell simulator can now be performed to study growth processes in skeletal muscle. Conditions in the mechanical cell simulator were defined where mechanical activity can either prevent muscle wasting or stimulate muscle growth. The role of endogenous and exogenous growth factors in tension-induced muscle growth is being investigated under the defined conditions of tissue culture.

Inhibition of vascular endothelial growth factor-induced angiogenesis suppresses tumour growth in vivo

NASA Astrophysics Data System (ADS)

Kim, K. Jin; Li, Bing; Winer, Jane; Armanini, Mark; Gillett, Nancy; Phillips, Heidi S.; Ferrara, Napoleone

1993-04-01

THE development of new blood vessels (angiogenesis) is required for many physiological processes including embryogenesis, wound healing and corpus luteum formation1,2. Blood vessel neoformation is also important in the pathogenesis of many disorders1-5, particularly rapid growth and metastasis of solid tumours3-5. There are several potential mediators of tumour angiogenesis, including basic and acidic fibroblast growth factors, tumour necrosis factor-α and transforming factors-α and -β 1,2. But it is unclear whether any of these agents actually mediates angiogenesis and tumour growth in vivo. Vascular endothelial growth factor (VEGF) is an endothelial cell-specific mitogen and an angiogenesis inducer released by a variety of tumour cells and expressed in human tumours in situ. To test whether VEGF may be a tumour angiogenesis factor in vivo, we injected human rhabdomyosar-coma, glioblastoma multiforme or leiomyosarcoma cell lines into nude mice. We report here that treatment with a monoclonal antibody specific for VEGF inhibited the growth of the tumours, but had no effect on the growth rate of the tumour cells In vitro. The density of vessels was decreased in the antibody-treated tumours. These findings demonstrate that inhibition of the action of an angiogenic factor spontaneously produced by tumour cells may suppress tumour growth in vivo.

Fibroblast growth factor receptor inhibitors.

PubMed

Kumar, Suneel B V S; Narasu, Lakshmi; Gundla, Rambabu; Dayam, Raveendra; J A R P, Sarma

2013-01-01

Fibroblast growth factor receptors (FGFRs) play an important role in embryonic development, angiogenesis, wound healing, cell proliferation and differentiation. The fibroblast growth factor receptor (FGFR) isoforms have been under intense scrutiny for effective anticancer drug candidates. The fibroblast growth factor (FGF) and its receptor (FGFR) provide another pathway that seems critical to monitoring angiogenesis. Recent findings suggest that FGFR mediates signaling, regulates the PKM2 activity, and plays a crucial role in cancer metabolism. The current review also covers the recent findings on the role of FGFR1 in cancer metabolism. This paper reviews the progress, mechanism, and binding modes of recently known kinase inhibitors such as PD173074, SU series and other inhibitors still under clinical development. Some of the structural classes that will be highlighted in this review include Pyrido[2,3-d]pyrimidines, Indolin- 2-one, Pyrrolo[2,1-f][1,2,4]triazine, Pyrido[2,3-d]pyrimidin-7(8H)-one, and 1,6- Naphthyridin-2(1H)-ones.

Expression of a transmembrane phosphotyrosine phosphatase inhibits cellular response to platelet-derived growth factor and insulin-like growth factor-1.

PubMed

Mooney, R A; Freund, G G; Way, B A; Bordwell, K L

1992-11-25

Tyrosine phosphorylation is a mechanism of signal transduction shared by many growth factor receptors and oncogene products. Phosphotyrosine phosphatases (PTPases) potentially modulate or counter-regulate these signaling pathways. To test this hypothesis, the transmembrane PTPase CD45 (leukocyte common antigen) was expressed in the murine cell line C127. Hormone-dependent autophosphorylation of the platelet-derived growth factor (PDGF) and insulin-like growth factor-1 (IGF-1) receptors was markedly reduced in cells expressing the transmembrane PTPase. Tyrosine phosphorylation of other PDGF-dependent phosphoproteins (160, 140, and 55 kDa) and IGF-1-dependent phosphoproteins (145 kDa) was similarly decreased. Interestingly, the pattern of growth factor-independent tyrosine phosphorylations was comparable in cells expressing the PTPase and control cells. This suggests a selectivity or accessibility of the PTPase limited to a subset of cellular phosphotyrosyl proteins. The maximum mitogenic response to PDGF and IGF-1 in cells expressing the PTPase was decreased by 67 and 71%, respectively. These results demonstrate that a transmembrane PTPase can both affect the tyrosine phosphorylation state of growth factor receptors and modulate proximal and distal cellular responses to the growth factors.

Cross-talk between GPER and growth factor signaling.

PubMed

Lappano, Rosamaria; De Marco, Paola; De Francesco, Ernestina Marianna; Chimento, Adele; Pezzi, Vincenzo; Maggiolini, Marcello

2013-09-01

G protein-coupled receptors (GPCRs) and growth factor receptors mediate multiple physio-pathological responses to a diverse array of extracellular stimuli. In this regard, it has been largely demonstrated that GPCRs and growth factor receptors generate a multifaceted signaling network, which triggers relevant biological effects in normal and cancer cells. For instance, some GPCRs transactivate the epidermal growth factor receptor (EGFR), which stimulates diverse transduction pathways leading to gene expression changes, cell migration, survival and proliferation. Moreover, it has been reported that a functional interaction between growth factor receptors and steroid hormones like estrogens is involved in the growth of many types of tumors as well as in the resistance to endocrine therapy. This review highlights recent findings on the cross-talk between a member of the GPCR family, the G protein-coupled estrogen receptor 1 (GPER, formerly known as GPR30) and two main growth factor receptors like EGFR and insulin-like growth factor-I receptor (IGF-IR). The biological implications of the functional interaction between these important mediators of cell responses particularly in cancer are discussed. This article is part of a Special Issue entitled 'CSR 2013'. Copyright © 2013 Elsevier Ltd. All rights reserved.

Time dependent impact of perinatal hypoxia on growth hormone, insulin-like growth factor 1 and insulin-like growth factor binding protein-3.

PubMed

Kartal, Ömer; Aydınöz, Seçil; Kartal, Ayşe Tuğba; Kelestemur, Taha; Caglayan, Ahmet Burak; Beker, Mustafa Caglar; Karademir, Ferhan; Süleymanoğlu, Selami; Kul, Mustafa; Yulug, Burak; Kilic, Ertugrul

2016-08-01

Hypoxic-ischemia (HI) is a widely used animal model to mimic the preterm or perinatal sublethal hypoxia, including hypoxic-ischemic encephalopathy. It causes diffuse neurodegeneration in the brain and results in mental retardation, hyperactivity, cerebral palsy, epilepsy and neuroendocrine disturbances. Herein, we examined acute and subacute correlations between neuronal degeneration and serum growth factor changes, including growth hormone (GH), insulin-like growth factor 1 (IGF-1) and insulin-like growth factor binding protein-3 (IGFBP-3) after hypoxic-ischemia (HI) in neonatal rats. In the acute phase of hypoxia, brain volume was increased significantly as compared with control animals, which was associated with reduced GH and IGF-1 secretions. Reduced neuronal survival and increased DNA fragmentation were also noticed in these animals. However, in the subacute phase of hypoxia, neuronal survival and brain volume were significantly decreased, accompanied by increased apoptotic cell death in the hippocampus and cortex. Serum GH, IGF-1, and IGFBP-3 levels were significantly reduced in the subacute phase of HI. Significant retardation in the brain and body development were noted in the subacute phase of hypoxia. Here, we provide evidence that serum levels of growth-hormone and factors were decreased in the acute and subacute phase of hypoxia, which was associated with increased DNA fragmentation and decreased neuronal survival.

Thin-plate spline analysis of craniofacial growth in Class I and Class II subjects.

PubMed

Franchi, Lorenzo; Baccetti, Tiziano; Stahl, Franka; McNamara, James A

2007-07-01

To compare the craniofacial growth characteristics of untreated subjects with Class II division 1 malocclusion with those of subjects with normal (Class I) occlusion from the prepubertal through the postpubertal stages of development. The Class II division 1 sample consisted of 17 subjects (11 boys and six girls). The Class I sample also consisted of 17 subjects (13 boys and four girls). Three craniofacial regions (cranial base, maxilla, and mandible) were analyzed on the lateral cephalograms of the subjects in both groups by means of thin-plate spline analysis at T1 (prepubertal) and T2 (postpubertal). Both cross-sectional and longitudinal comparisons were performed on both size and shape differences between the two groups. The results showed an increased cranial base angulation as a morphological feature of Class II malocclusion at the prepubertal developmental phase. Maxillary changes in either shape or size were not significant. Subjects with Class II malocclusion exhibited a significant deficiency in the size of the mandible at the completion of active craniofacial growth as compared with Class I subjects. A significant deficiency in the size of the mandible became apparent in Class II subjects during the circumpubertal period and it was still present at the completion of active craniofacial growth.

Relaxation of Insulin-Like Growth Factor II Imprinting in Prostate Cancer Development

DTIC Science & Technology

2005-01-01

in the Results in Senescence and Biallelic IGF2 Expression- Hypo - mouse and are putative ICRs (Fig. 3A). At MR2, located within methylation has been...elderly. In In mammals, reproduction is controlled by the hypo - the case of prostate cancer, the most commonly diagnosed thalamic--pituitary-gonadal... caloric the ligands IGF-I, IGF-II, cell-surface receptors and binding intake or hormonal exposure), loss of imprinting of IGF-II proteins. Epidemiological

miR-24 and miR-122 Negatively Regulate the Transforming Growth Factor-β/Smad Signaling Pathway in Skeletal Muscle Fibrosis.

PubMed

Sun, Yaying; Wang, Hui; Li, Yan; Liu, Shaohua; Chen, Jiwu; Ying, Hao

2018-06-01

Fibrosis is common after skeletal muscle injury, undermining tissue regeneration and function. The mechanism underlying skeletal muscle fibrosis remains unveiled. Transforming growth factor-β/Smad signaling pathway is supposed to play a pivotal role. However, how microRNAs interact with transforming growth factor-β/Smad-related muscle fibrosis remains unclear. We showed that microRNA (miR)-24-3p and miR-122-5p declined in skeletal muscle fibrosis, which was a consequence of transforming growth factor-β. Upregulating Smad4 suppressed two microRNAs, whereas inhibiting Smad4 elevated microRNAs. Luciferase reporter assay and chromatin immunoprecipitation confirmed that Smad4 directly inhibited two microRNAs. On the other hand, overexpression of these two miRs retarded fibrotic process. We further identified that Smad2 was a direct target of miR-24-3p, whereas miR-122-5p targeted transforming growth factor-β receptor-II. Both targets were important participants in transforming growth factor-β/Smad signaling. Taken together, a positive feedback loop in transforming growth factor-β/Smad4 signaling pathway in skeletal muscle fibrosis was identified. Transforming growth factor-β/Smad axis could be downregulated by microRNAs. This effect, however, was suppressed by Smad4, the downstream of transforming growth factor-β. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Targeted delivery of growth factors in ischemic stroke animal models.

PubMed

Rhim, Taiyoun; Lee, Minhyung

2016-01-01

Ischemic stroke is caused by reduced blood supply and leads to loss of brain function. The reduced oxygen and nutrient supply stimulates various physiological responses, including induction of growth factors. Growth factors prevent neuronal cell death, promote neovascularization, and induce cell growth. However, the concentration of growth factors is not sufficient to recover brain function after the ischemic damage, suggesting that delivery of growth factors into the ischemic brain may be a useful treatment for ischemic stroke. In this review, various approaches for the delivery of growth factors to ischemic brain tissue are discussed, including local and targeting delivery systems. To develop growth factor therapy for ischemic stroke, important considerations should be taken into account. First, growth factors may have possible side effects. Thus, concentration of growth factors should be restricted to the ischemic tissues by local administration or targeted delivery. Second, the duration of growth factor therapy should be optimized. Growth factor proteins may be degraded too fast to have a high enough therapeutic effect. Therefore, delivery systems for controlled release or gene delivery may be useful. Third, the delivery systems to the brain should be optimized according to the delivery route.

Mechano growth factor (MGF) and transforming growth factor (TGF)-β3 functionalized silk scaffolds enhance articular hyaline cartilage regeneration in rabbit model.

PubMed

Luo, Ziwei; Jiang, Li; Xu, Yan; Li, Haibin; Xu, Wei; Wu, Shuangchi; Wang, Yuanliang; Tang, Zhenyu; Lv, Yonggang; Yang, Li

2015-06-01

Damaged cartilage has poor self-healing ability and usually progresses to scar or fibrocartilaginous tissue, and finally degenerates to osteoarthritis (OA). Here we demonstrated that one of alternative isoforms of IGF-1, mechano growth factor (MGF) acted synergistically with transforming growth factor β3 (TGF-β3) embedded in silk fibroin scaffolds to induce chemotactic homing and chondrogenic differentiation of mesenchymal stem cells (MSCs). Combination of MGF and TGF-β3 significantly increased cell recruitment up to 1.8 times and 2 times higher than TGF-β3 did in vitro and in vivo. Moreover, MGF increased Collagen II and aggrecan secretion of TGF-β3 induced hMSCs chondrogenesis, but decreased Collagen I in vitro. Silk fibroin (SF) scaffolds have been widely used for tissue engineering, and we showed that methanol treated pured SF scaffolds were porous, similar to compressive module of native cartilage, slow degradation rate and excellent drug released curves. At 7 days after subcutaneous implantation, TGF-β3 and MGF functionalized silk fibroin scaffolds (STM) recruited more CD29+/CD44+cells (P<0.05). Similarly, more cartilage-like extracellular matrix and less fibrillar collagen were detected in STM scaffolds than that in TGF-β3 modified scaffolds (ST) at 2 months after subcutaneous implantation. When implanted into articular joints in a rabbit osteochondral defect model, STM scaffolds showed the best integration into host tissues, similar architecture and collagen organization to native hyaline cartilage, as evidenced by immunostaining of aggrecan, collagen II and collagen I, as well as Safranin O and Masson's trichrome staining, and histological evalution based on the modified O'Driscoll histological scoring system (P<0.05), indicating that MGF and TGF-β3 might be a better candidate for cartilage regeneration. This study demonstrated that TGF-β3 and MGF functionalized silk fibroin scaffolds enhanced endogenous stem cell recruitment and facilitated in

Bud detachment in hydra requires activation of fibroblast growth factor receptor and a Rho–ROCK–myosin II signaling pathway to ensure formation of a basal constriction

PubMed Central

Holz, Oliver; Apel, David; Steinmetz, Patrick; Lange, Ellen; Hopfenmüller, Simon; Ohler, Kerstin; Sudhop, Stefanie

2017-01-01

Background: Hydra propagates asexually by exporting tissue into a bud, which detaches 4 days later as a fully differentiated young polyp. Prerequisite for detachment is activation of fibroblast growth factor receptor (FGFR) signaling. The mechanism which enables constriction and tissue separation within the monolayered ecto‐ and endodermal epithelia is unknown. Results: Histological sections and staining of F‐actin by phalloidin revealed conspicuous cell shape changes at the bud detachment site indicating a localized generation of mechanical forces and the potential enhancement of secretory functions in ectodermal cells. By gene expression analysis and pharmacological inhibition, we identified a candidate signaling pathway through Rho, ROCK, and myosin II, which controls bud base constriction and rearrangement of the actin cytoskeleton. Specific regional myosin phosphorylation suggests a crucial role of ectodermal cells at the detachment site. Inhibition of FGFR, Rho, ROCK, or myosin II kinase activity is permissive for budding, but represses myosin phosphorylation, rearrangement of F‐actin and constriction. The young polyp remains permanently connected to the parent by a broad tissue bridge. Conclusions: Our data suggest an essential role of FGFR and a Rho‐ROCK‐myosin II pathway in the control of cell shape changes required for bud detachment. Developmental Dynamics 246:502–516, 2017. © 2017 The Authors Developmental Dynamics published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists PMID:28411398

Priming Dental Pulp Stem Cells With Fibroblast Growth Factor-2 Increases Angiogenesis of Implanted Tissue-Engineered Constructs Through Hepatocyte Growth Factor and Vascular Endothelial Growth Factor Secretion

PubMed Central

Gorin, Caroline; Rochefort, Gael Y.; Bascetin, Rumeyza; Ying, Hanru; Lesieur, Julie; Sadoine, Jérémy; Beckouche, Nathan; Berndt, Sarah; Novais, Anita; Lesage, Matthieu; Hosten, Benoit; Vercellino, Laetitia; Merlet, Pascal; Le-Denmat, Dominique; Marchiol, Carmen; Letourneur, Didier; Nicoletti, Antonino; Vital, Sibylle Opsahl; Poliard, Anne; Salmon, Benjamin; Germain, Stéphane

2016-01-01

Tissue engineering strategies based on implanting cellularized biomaterials are promising therapeutic approaches for the reconstruction of large tissue defects. A major hurdle for the reliable establishment of such therapeutic approaches is the lack of rapid blood perfusion of the tissue construct to provide oxygen and nutrients. Numerous sources of mesenchymal stem cells (MSCs) displaying angiogenic potential have been characterized in the past years, including the adult dental pulp. Establishment of efficient strategies for improving angiogenesis in tissue constructs is nevertheless still an important challenge. Hypoxia was proposed as a priming treatment owing to its capacity to enhance the angiogenic potential of stem cells through vascular endothelial growth factor (VEGF) release. The present study aimed to characterize additional key factors regulating the angiogenic capacity of such MSCs, namely, dental pulp stem cells derived from deciduous teeth (SHED). We identified fibroblast growth factor-2 (FGF-2) as a potent inducer of the release of VEGF and hepatocyte growth factor (HGF) by SHED. We found that FGF-2 limited hypoxia-induced downregulation of HGF release. Using three-dimensional culture models of angiogenesis, we demonstrated that VEGF and HGF were both responsible for the high angiogenic potential of SHED through direct targeting of endothelial cells. In addition, FGF-2 treatment increased the fraction of Stro-1+/CD146+ progenitor cells. We then applied in vitro FGF-2 priming to SHED before encapsulation in hydrogels and in vivo subcutaneous implantation. Our results showed that FGF-2 priming is more efficient than hypoxia at increasing SHED-induced vascularization compared with nonprimed controls. Altogether, these data demonstrate that FGF-2 priming enhances the angiogenic potential of SHED through the secretion of both HGF and VEGF. Significance The results from the present study show that fibroblast growth factor-2 (FGF-2) priming is more

Role of growth hormone, insulin-like growth factor-I, and insulin-like growth factor binding proteins in the catabolic response to injury and infection.

PubMed

Lang, Charles H; Frost, Robert A

2002-05-01

The erosion of lean body mass resulting from protracted critical illness remains a significant risk factor for increased morbidity and mortality in this patient population. Previous studies have documented the well known impairment in nitrogen balance results from both an increase in muscle protein degradation as well as a decreased rate of both myofibrillar and sacroplasmic protein synthesis. This protein imbalance may be caused by an increased presence or activity of various catabolic agents, such as tumor necrosis factor-alpha, interleukin-1 beta, interleukin-6 or glucocorticoids, or may be mediated via a decreased concentration or responsiveness to various anabolic hormones, such as growth hormone or insulin-like growth factor-I. This review focuses on recent developments pertaining to the importance of alterations in the growth hormone-insulin-like growth factor-I axis as a mechanism for the observed defects in muscle protein balance.

The Factor Structure of the Beck Depression Inventory-II: An Evaluation

ERIC Educational Resources Information Center

Vanheule, Stijn; Desmet, Mattias; Groenvynck, Hans; Rosseel, Yves; Fontaine, Johnny

2008-01-01

The Beck Depression Inventory-II (BDI-II) is a frequently used scale for measuring depressive severity. BDI-II data (404 clinical; 695 nonclinical adults) were analyzed by means of confirmatory factor analysis to test whether the factor structure model with a somatic-affective and cognitive component of depression, formulated by Beck and…

Constructing a blood vessel on the porous scaffold modified with vascular endothelial growth factor and basic fibroblast growth factor

NASA Astrophysics Data System (ADS)

Sevostyanova, V. V.; Matveeva, V. G.; Antonova, L. V.; Velikanova, E. A.; Shabaev, A. R.; Senokosova, E. A.; Krivkina, E. O.; Vasyukov, G. Yu.; Glushkova, T. V.; Kudryavtseva, Yu. A.; Barbarash, O. L.; Barbarash, L. S.

2016-11-01

Incorporation of the growth factors into biodegradable polymers is a promising approach for the fabrication of tissue-engineered vascular grafts. Here we blended poly(ɛ-caprolactone) (PCL) with poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) following incorporation of either vascular endothelial growth factor (VEGF) or basic fibroblast growth factor (bFGF) and then fabricated electrospun 2 mm diameter vascular grafts. Grafts without the growth factors were used as a control group. Structure of the grafts was assessed utilizing scanning electron microscopy. We further implanted our grafts into rat abdominal aorta for 1 and 3 months with the aim to test endothelialization, cell infiltration, and patency in vivo. Histological and immunofluorescence examination demonstrated enhanced endothelialization and cell infiltration of the grafts with either VEGF or bFGF compared to those without the growth factors. Grafts with VEGF showed higher patency compared to those with bFGF; however, bFGF promoted migration of smooth muscle cells and fibroblasts into the graft. Therefore, we conclude that incorporation of VEGF and bFGF into the inner and medial/outer layer, respectively, can be a promising option for the fabrication of tissue-engineered vascular grafts.

Crystal Growth of II-VI Semiconducting Alloys by Directional Solidification

NASA Technical Reports Server (NTRS)

Lehoczky, Sandor L.; Szofran, Frank R.; Su, Ching-Hua; Cobb, Sharon D.; Scripa, Rosalia A.; Sha, Yi-Gao

1999-01-01

This research study is investigating the effects of a microgravity environment during the crystal growth of selected II-VI semiconducting alloys on their compositional, metallurgical, electrical and optical properties. The on-going work includes both Bridgman-Stockbarger and solvent growth methods, as well as growth in a magnetic field. The materials investigated are II-VI, Hg(1-x)Zn(x)Te, and Hg(1-x)Zn(x)Se, where x is between 0 and 1 inclusive, with particular emphasis on x-values appropriate for infrared detection and imaging in the 5 to 30 micron wavelength region. Wide separation between the liquidus and solidus of the phase diagrams with consequent segregation during solidification and problems associated with the high volatility of one of the components (Hg), make the preparation of homogeneous, high-quality, bulk crystals of the alloys an extremely difficult nearly an impossible task in a gravitational environment. The three-fold objectives of the on-going investigation are as follows: (1) To determine the relative contributions of gravitationally-driven fluid flows to the compositional redistribution observed during the unidirectional crystal growth of selected semiconducting solid solution alloys having large separation between the liquidus and solidus of the constitutional phase diagram; (2) To ascertain the potential role of irregular fluid flows and hydrostatic pressure effects in generation of extended crystal defects and second-phase inclusions in the crystals; and, (3) To obtain a limited amount of "high quality" materials needed for bulk crystal property characterizations and for the fabrication of various device structures needed to establish ultimate material performance limits. The flight portion of the study was to be accomplished by performing growth experiments using the Crystal Growth Furnace (CGF) manifested to fly on various Spacelab missions.

Removal of GaAs growth substrates from II-VI semiconductor heterostructures

NASA Astrophysics Data System (ADS)

Bieker, S.; Hartmann, P. R.; Kießling, T.; Rüth, M.; Schumacher, C.; Gould, C.; Ossau, W.; Molenkamp, L. W.

2014-04-01

We report on a process that enables the removal of II-VI semiconductor epilayers from their GaAs growth substrate and their subsequent transfer to arbitrary host environments. The technique combines mechanical lapping and layer selective chemical wet etching and is generally applicable to any II-VI layer stack. We demonstrate the non-invasiveness of the method by transferring an all-II-VI magnetic resonant tunneling diode. High resolution x-ray diffraction proves that the crystal integrity of the heterostructure is preserved. Transport characterization confirms that the functionality of the device is maintained and even improved, which is ascribed to completely elastic strain relaxation of the tunnel barrier layer.

Expression and localization of insulin-like growth factor system in corpus luteum during different stages of estrous cycle in water buffaloes (Bubalus bubalis) and the effect of insulin-like growth factor I on production of vascular endothelial growth factor and progesterone in luteal cells cultured in vitro.

PubMed

Uniyal, S; Panda, R P; Chouhan, V S; Yadav, V P; Hyder, I; Dangi, S S; Gupta, M; Khan, F A; Sharma, G T; Bag, S; Sarkar, M

2015-01-01

This study investigated the expression and localization of insulin-like growth factor (IGF) system at different stages of buffalo CL and the role of IGF-I in stimulating vascular endothelial growth factor (VEGF) and progesterone (P4) production in cultured luteal cells. The mRNA expression of IGF system, VEGF, steroidogenic acute regulatory protein, P450scc, and hydroxysteroid dehydrogenase (HSD) was investigated by quantitative real-time polymerase chain reaction (PCR). Protein expression of IGF was demonstrated by Western blot and localization by immunohistochemistry. Progesterone and VEGF production was assayed using RIA and ELISA. A relatively high mRNA expression of IGF-I and IGF-II in early, mid- and late luteal phases with immunoreactivity mostly restricted to cytoplasm of large luteal cells indicates their autocrine role, whereas very weak immunoreactivity in endothelial cells during the mid-luteal phase indicates their paracrine role. Insulin-like growth factor receptors, IGF-IR and IGF-IIR, were restricted to large luteal cells with high mRNA and protein expressions in the mid-luteal phase. The significantly higher expression of insulin-like growth factor binding protein (IGFBP)-1, -3, -5, and -6 in the early or mid-luteal phase suggested their stimulatory role, whereas that of IGFBP-2 and -4 in mid-, late, and regressive luteal stages implied their inhibitory role. The mRNA expressions of key steroidogenic factors and VEGF were significantly higher (P < 0.05) when the culture medium was supplemented with 100 ng/mL of IGF-I for 72 hours. Moreover, IGF-I at a dose of 100 ng/mL increased P4 and VEGF production (P < 0.05). It can be concluded that IGF family members via their autocrine and paracrine effect play significant roles in promoting angiogenesis through the production of VEGF in luteal cells and steroid synthesis through the production of key steroidogenic factors. Copyright © 2015 Elsevier Inc. All rights reserved.

Gene expression analysis of growth factor receptors in human chondrocytes in monolayer and 3D pellet cultures

PubMed Central

Witt, Anika; Salamon, Achim; Boy, Diana; Hansmann, Doris; Büttner, Andreas; Wree, Andreas; Bader, Rainer; Jonitz-Heincke, Anika

2017-01-01

The main goal of cartilage repair is to create functional tissue by enhancing the in vitro conditions to more physiological in vivo conditions. Chondrogenic growth factors play an important role in influencing cartilage homeostasis. Insulin-like growth factor (IGF)-1 and transforming growth factor (TGF)-β1 affect the expression of collagen type II (Col2) and glycosaminoglycans (GAGs) and, therefore, the targeted use of growth factors could make chondrogenic redifferentiation more efficient. In the present study, human chondrocytes were postmortally isolated from healthy articular cartilage and cultivated as monolayer or 3D pellet cultures either under normoxia or hypoxia and stimulated with IGF-1 and/or TGF-β1 to compare the impact of the different growth factors. The mRNA levels of the specific receptors (IGF1R, TGFBR1, TGFBR2) were analyzed at different time points. Moreover, gene expression rates of collagen type 1 and 2 in pellet cultures were observed over a period of 5 weeks. Additionally, hyaline-like Col2 protein and sulphated GAG (sGAG) levels were quantified. Stimulation with IGF-1 resulted in an enhanced expression of IGF1R and TGFBR2 whereas TGF-β1 stimulated TGFBR1 in the monolayer and pellet cultures. In monolayer, the differences reached levels of significance. This effect was more pronounced under hypoxic culture conditions. In pellet cultures, increased amounts of Col2 protein and sGAGs after incubation with TGF-β1 and/or IGF-1 were validated. In summary, constructing a gene expression profile regarding mRNA levels of specific growth factor receptors in monolayer cultures could be helpful for a targeted application of growth factors in cartilage tissue engineering. PMID:28534942

TERATOGENIC RESPONSES ARE MODULATED IN MICE LACKING EXPRESSION OF EPIDERMAL GROWTH FACTOR (EGF) AND TRANSFORMING GROWTH FACTOR-ALPHA (TGF)

EPA Science Inventory

TITLE:
TERATOGENIC RESPONSES ARE MODULATED IN MICE LACKING EXPRESSION OF EPIDERMAL GROWTH FACTOR (EGF) AND TRANSFORMING GROWTH FACTOR-ALPHA (TGF). AUTHORS (ALL): Abbott, Barbara D.1; Best, Deborah S.1; Narotsky, Michael G.1. SPONSOR NAME: None INSTITUTIONS (ALL): 1. Repro Tox ...

Delivery of growth factors for tissue regeneration and wound healing.

PubMed

Koria, Piyush

2012-06-01

Growth factors are soluble secreted proteins capable of affecting a variety of cellular processes important for tissue regeneration. Consequently, the self-healing capacity of patients can be augmented by artificially enhancing one or more processes important for healing through the application of growth factors. However, their application in clinics remains limited due to lack of robust delivery systems and biomaterial carriers. Interestingly, all clinically approved therapies involving growth factors utilize some sort of a biomaterial carrier for growth factor delivery. This suggests that biomaterial delivery systems are extremely important for successful usage of growth factors in regenerative medicine. This review outlines the role of growth factors in tissue regeneration, and their application in both pre-clinical animal models of regeneration and clinical trials is discussed. Additionally, current status of biomaterial substrates and sophisticated delivery systems such as nanoparticles for delivery of exogenous growth factors and peptides in humans are reviewed. Finally, issues and possible future research directions for growth factor therapy in regenerative medicine are discussed.

Fibroblast Growth Factor 2: An Epithelial Ductal Cell Growth Inhibitor That Drops Out in Breast Cancer

DTIC Science & Technology

2009-10-01

AD_________________ Award Number: W81XWH-08-1-0708 TITLE: Fibroblast Growth Factor 2: an...September 2008 – 14 September 2009 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Fibroblast Growth Factor 2: an Epithelial Ductal Cell Growth Inhibitor...9 Fibroblast Growth Factor -2: an Epithelial Ductal Cell Growth Inhibitor that Drops Out in Breast Cancer

Endogenous versus Exogenous Growth Factor Regulation of Articular Chondrocytes

PubMed Central

Shi, Shuiliang; Chan, Albert G.; Mercer, Scott; Eckert, George J.; Trippel, Stephen B.

2014-01-01

Anabolic growth factors that regulate the function of articular chondrocytes are candidates for articular cartilage repair. Such factors may be delivered by pharmacotherapy in the form of exogenous proteins, or by gene therapy as endogenous proteins. It is unknown whether delivery method influences growth factor effectiveness in regulating articular chondrocyte reparative functions. We treated adult bovine articular chondrocytes with exogenous recombinant insulin-like growth factor-I (IGF-I) and transforming growth factor-beta1 (TGF-β1), or with the genes encoding these growth factors for endogenous production. Treatment effects were measured as change in chondrocyte DNA content, glycosaminoglycan production, and aggrecan gene expression. We found that IGF-I stimulated chondrocyte biosynthesis similarly when delivered by either exogenous or endogenous means. In contrast, exogenous TGF-ß1 stimulated these reparative functions, while endogenous TGF-ß1 had little effect. Endogenous TGF-ß1 became more bioactive following activation of the transgene protein product. These data indicate that effective mechanisms of growth factor delivery for articular cartilage repair may differ for different growth factors. In the case of IGF-I, gene therapy or protein therapy appear to be viable options. In contrast, TGF-ß1 gene therapy may be constrained by a limited ability of chondrocytes to convert latent complexes to an active form. PMID:24105960

Fibroblast Growth Factors and Vascular Endothelial Growth Factor Promote Cardiac Reprogramming under Defined Conditions

PubMed Central

Yamakawa, Hiroyuki; Muraoka, Naoto; Miyamoto, Kazutaka; Sadahiro, Taketaro; Isomi, Mari; Haginiwa, Sho; Kojima, Hidenori; Umei, Tomohiko; Akiyama, Mizuha; Kuishi, Yuki; Kurokawa, Junko; Furukawa, Tetsushi; Fukuda, Keiichi; Ieda, Masaki

2015-01-01

Summary Fibroblasts can be directly reprogrammed into cardiomyocyte-like cells (iCMs) by overexpression of cardiac transcription factors, including Gata4, Mef2c, and Tbx5; however, this process is inefficient under serum-based culture conditions, in which conversion of partially reprogrammed cells into fully reprogrammed functional iCMs has been a major hurdle. Here, we report that a combination of fibroblast growth factor (FGF) 2, FGF10, and vascular endothelial growth factor (VEGF), termed FFV, promoted cardiac reprogramming under defined serum-free conditions, increasing spontaneously beating iCMs by 100-fold compared with those under conventional serum-based conditions. Mechanistically, FFV activated multiple cardiac transcriptional regulators and converted partially reprogrammed cells into functional iCMs through the p38 mitogen-activated protein kinase and phosphoinositol 3-kinase/AKT pathways. Moreover, FFV enabled cardiac reprogramming with only Mef2c and Tbx5 through the induction of cardiac reprogramming factors, including Gata4. Thus, defined culture conditions promoted the quality of cardiac reprogramming, and this finding provides new insight into the mechanism of cardiac reprogramming. PMID:26626177

[Studying the association between genetic polymorphism of growth factors and the development of primary open-angle glaucoma].

PubMed

Kirilenko, M Yu; Tikunova, E V; Sirotina, S S; Polonikov, A V; Bushueva, O Yu; Churnosov, M I

Primary open-angle glaucoma (POAG) is a multifactorial disease, etiopathogenesis of which largely depends on growth factors. Possessing a variety of medical and biological effects, these cytokines may influence the development and progression of POAG. to reveal the role of genetic polymorphisms of growth factors in predisposition to developing POAG that is refractory to local hypotensive therapy. The object of the study were 162 patients with stage II-III POAG, in whom local hypotensive therapy was inefficient, 90 patients with stage II-III POAG well controlled on local hypotensive therapy, and 191 controls. The material for the study was venous blood taken from the cubital vein of a proband. Isolation of genomic DNA was performed by phenol-chloroform extraction. Analysis of genetic polymorphisms of growth factors was performed through allelic discrimination. For that, synthesis of DNA was carried out via polymerase chain reaction (PCR). It is found that the T IGFR-1 genetic variant (OR=1.34) and a combination of the C VEGF-A and T IGFR-1 genetic variants (OR=1.90) are risk factors of developing POAG that is refractory to local hypotensive therapy. A statistical model for predicting such a risk has been proposed that includes: VEGF-A с.-958C>T genetic marker (rs 833,061), age, concomitant non-inflammatory ocular diseases, microvascular changes in the conjunctiva, the degree of pigmentation of the angle of the anterior chamber, and pseudoexfoliative syndrome. Recognition accuracy of the model is 90.42%. The T IGFR-1 genetic variant and a combination of the C VEGF-A and T IGFR-1 genetic variants increase the risk of developing POAG that is refractory to local hypotensive therapy.

Endorsement of Growth Factors in Experiential Training Groups

ERIC Educational Resources Information Center

Kiweewa, John; Gilbride, Dennis; Luke, Melissa; Seward, Derek

2013-01-01

The purpose of this study was to identify student growth factors during a semester long Master's level group counseling class. Results indicated that 12 growth factors accounted for 86% of the total number of critical incidents that participants reported as influencing their personal growth and awareness during the group experience. Two other…

Placenta Growth Factor in Diabetic Wound Healing

PubMed Central

Cianfarani, Francesca; Zambruno, Giovanna; Brogelli, Laura; Sera, Francesco; Lacal, Pedro Miguel; Pesce, Maurizio; Capogrossi, Maurizio C.; Failla, Cristina Maria; Napolitano, Monica; Odorisio, Teresa

2006-01-01

Reduced microcirculation and diminished expression of growth factors contribute to wound healing impairment in diabetes. Placenta growth factor (PlGF), an angiogenic mediator promoting pathophysiological neovascularization, is expressed during cutaneous wound healing and improves wound closure by enhancing angiogenesis. By using streptozotocin-induced diabetic mice, we here demonstrate that PlGF induction is strongly reduced in diabetic wounds. Diabetic transgenic mice overexpressing PlGF in the skin displayed accelerated wound closure compared with diabetic wild-type littermates. Moreover, diabetic wound treatment with an adenovirus vector expressing the human PlGF gene (AdCMV.PlGF) significantly accelerated the healing process compared with wounds treated with a control vector. The analysis of treated wounds showed that PlGF gene transfer improved granulation tissue formation, maturation, and vascularization, as well as monocytes/macrophages local recruitment. Platelet-derived growth factor, fibroblast growth factor-2, and vascular endothelial growth factor mRNA levels were increased in AdCMV.PlGF-treated wounds, possibly enhancing PlGF-mediated effects. Finally, PlGF treatment stimulated cultured dermal fibroblast migration, pointing to a direct role of PlGF in accelerating granulation tissue maturation. In conclusion, our data indicate that reduced PlGF expression contributes to impaired wound healing in diabetes and that PlGF gene transfer to diabetic wounds exerts therapeutic activity by promoting different aspects of the repair process. PMID:17003476

Fibroblast Growth Factor 2: An Epithelial Ductal Cell Growth Inhibitor That Drops Out in Breast Cancer

DTIC Science & Technology

2011-10-01

fibroblast   growth   factor   receptors  and  their  prognostic...AD_________________ Award Number: W81XWH-08-1-0708 TITLE: Fibroblast Growth Factor 2: an...September 2008 – 14 September 2011 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Fibroblast Growth Factor 2: an Epithelial Ductal Cell Growth

Therapeutic angiogenesis: angiogenic growth factors for ischemic heart disease.

PubMed

Henning, Robert J

2016-09-01

Stem cells encode vascular endothelial growth factors (VEGFs), fibroblastic growth factors (FGFs), stem cell factor, stromal cell-derived factor, platelet growth factor and angiopoietin that can contribute to myocardial vascularization. VEGFs and FGFs are the most investigated growth factors. VEGFs regulate angiogenesis and vasculogenesis. FGFs stimulate vessel cell proliferation and differentiation and are regulators of endothelial cell migration, proliferation and survival. Clinical trials of VEGF or FGF for myocardial angiogenesis have produced disparate results. The efficacy of therapeutic angiogenesis can be improved by: (1) identifying the most optimal patients; (2) increased knowledge of angiogenic factor pharmacokinetics and proper dose; (3) prolonging contact of angiogenic factors with the myocardium; (4) increasing the efficiency of VEGF or FGF gene transduction; and (5) utilizing PET or MRI to measure myocardial perfusion and perfusion reserve.

Plasma insulin-like growth factors, insulin-like binding protein-3, and outcome in metastatic colorectal cancer: results from intergroup trial N9741.

PubMed

Fuchs, Charles S; Goldberg, Richard M; Sargent, Daniel J; Meyerhardt, Jeffrey A; Wolpin, Brian M; Green, Erin M; Pitot, Henry C; Pollak, Michael

2008-12-15

Insulin-like growth factor (IGF)-I and IGF-II stimulate neoplastic cell growth and inhibit apoptosis, whereas IGF-binding protein-3 (IGFBP-3) inhibits the bioavailability of IGF-I and has independent proapoptotic activity. We examined the influence of baseline plasma levels of IGF-I, IGF-II, IGFBP-3, and C-peptide on outcome among patients receiving first-line chemotherapy for metastatic colorectal cancer. The plasma levels of IGF-I, IGF-II, IGFBP-3, and C-peptide as well as data on prognostic factors and body size were measured at baseline among 527 patients participating in a randomized trial of first-line chemotherapy for metastatic colorectal cancer. Higher baseline plasma IGFBP-3 levels were associated with a significantly greater chemotherapy response rate (P = 0.03) after adjusting for other prognostic factors, whereas neither IGF-I nor IGF-II levels significantly predicted tumor response. Higher levels of IGF-I, IGF-II, and IGFBP-3 were all univariately associated with improved overall survival (P = 0.0001 for all). In a model that mutually adjusted for IGF-I and IGFBP-3, as well as other prognostic factors, increasing baseline-circulating IGFBP-3 was associated with a significantly longer time to tumor progression (P = 0.03), whereas circulating IGF-I was not associated with disease progression (P = 0.95). Levels of C-peptide were not associated with any measure of patient outcome. Among colorectal cancer patients receiving first-line chemotherapy, increasing levels of IGFBP-3, an endogenous antagonist to IGF-I, are associated with an improved objective treatment response and a prolonged time to cancer progression. The IGF pathway may represent an important target for future treatment strategies.

Bud detachment in hydra requires activation of fibroblast growth factor receptor and a Rho-ROCK-myosin II signaling pathway to ensure formation of a basal constriction.

PubMed

Holz, Oliver; Apel, David; Steinmetz, Patrick; Lange, Ellen; Hopfenmüller, Simon; Ohler, Kerstin; Sudhop, Stefanie; Hassel, Monika

2017-07-01

Hydra propagates asexually by exporting tissue into a bud, which detaches 4 days later as a fully differentiated young polyp. Prerequisite for detachment is activation of fibroblast growth factor receptor (FGFR) signaling. The mechanism which enables constriction and tissue separation within the monolayered ecto- and endodermal epithelia is unknown. Histological sections and staining of F-actin by phalloidin revealed conspicuous cell shape changes at the bud detachment site indicating a localized generation of mechanical forces and the potential enhancement of secretory functions in ectodermal cells. By gene expression analysis and pharmacological inhibition, we identified a candidate signaling pathway through Rho, ROCK, and myosin II, which controls bud base constriction and rearrangement of the actin cytoskeleton. Specific regional myosin phosphorylation suggests a crucial role of ectodermal cells at the detachment site. Inhibition of FGFR, Rho, ROCK, or myosin II kinase activity is permissive for budding, but represses myosin phosphorylation, rearrangement of F-actin and constriction. The young polyp remains permanently connected to the parent by a broad tissue bridge. Our data suggest an essential role of FGFR and a Rho-ROCK-myosin II pathway in the control of cell shape changes required for bud detachment. Developmental Dynamics 246:502-516, 2017. © 2017 The Authors Developmental Dynamics published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists. © 2017 The Authors Developmental Dynamics published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists.

Clinical Application of Growth Factors and Cytokines in Wound Healing

PubMed Central

Barrientos, Stephan; Brem, Harold; Stojadinovic, Olivera; Tomic-Canic, Marjana

2016-01-01

Wound healing is a complex and dynamic biological process that involves the coordinated efforts of multiple cell types and is executed and regulated by numerous growth factors and cytokines. There has been a drive in the past two decades to study the therapeutic effects of various growth factors in the clinical management of non-healing wounds (e.g. pressure ulcers, chronic venous ulcers, diabetic foot ulcers). For this review, we conducted a nonline search of Medline and Pub Medical and critically analyzed the literature regarding the role of growth factors and cytokines in the management of these wounds. We focused on currently approved therapies, emerging therapies and future research possibilities. In this review we discuss four growth factors and cytokines currently being used on and off label for the healing of wounds. These include: granulocyte-macrophage colony stimulating factor (GM-CSF), platelet derived growth factor (PDGF), vascular endothelial growth factor (VEGF), and basic fibroblast growth factor (bFGF). While the clinical results of using growth factors and cytokines are encouraging, many studies involved a small sample size and are disparate in measured endpoints. Therefore, further research is required to provide definitive evidence of efficacy. PMID:24942811

Differential Expression of Glypican-3 and Insulin–Like Growth Factor-II mRNAs and Alpha-Fetoprotein and Ki-67 Markers in HCV Related Hepatocellular Carcinomas In Egyptian Patients

PubMed

Saber, Mohamed A; MM AbdelHafiz, Samah; Khorshed, Fatma E; Aboushousha, Tarek S; Hamdy, Hussam EM; Seleem, Mohamed I; Soliman, Amira H

2017-01-01

Background: Increasing evidence indicates that in hepatocellular carcinomas (HCCs) abnormal gene expression, for example of glypican-3 (GPC-3) and insulin-like growth factor-II (IGF-II), are associated with the occurrence and progression of HCC. The objective of this study was to evaluate the differential expression of GPC-3 and IGF-II mRNAs in HCC tissues with a background of chronic hepatitis C virus (HCV) genotype 4 cirrhosis, in relation to Ki-67 and alpha-feto protein (AFP) tissue markers. Methods: One hundred and five patients with HCCs who had undergone hepatectomy, were included, after obtaining informed consent. Total RNA was extracted from malignant and corresponding peri-malignant liver tissues, and GPC-3 and IGF-II mRNAs in addition to beta-actin mRNA as an internal control, were evaluated in all samples by reverse transcriptase-polymerase chain reactions (RT-PCR). Routine histopathological diagnosis as well as immunohistochemical (IHC) staining using monoclonal antibodies for Ki-67 and AFP were also performed. Result: Expression of GPC-3 mRNA was positive in all HCC malignant tissue, with overexpression in 86/105 (81.9%); in respect to the grade of the tumor (1-3 grades), while in peri-malignant tissue it was over expressed only in 20/105 (19%). The IGF-II mRNA was over expressed in only 10/105 (9.5%) malignant and peri-malignant samples. AFP was expressed in 33.3% of malignant samples but absent in peri-malignant tissues. Ki-67 expression was significantly increased in malignant compared to peri-malignant tissue. Conclusion: GPC-3 and IGF II mRNAs may be good molecular markers for HCC, especially with a background of cirrhosis due to chronic HCV infection. Significant correlations were noted with the pattern of AFP and Ki-67 expression. Creative Commons Attribution License

Advances in pubertal growth and factors influencing it: Can we increase pubertal growth?

PubMed Central

Soliman, Ashraf; De Sanctis, Vincenzo; Elalaily, Rania; Bedair, Said

2014-01-01

Puberty is a period of development characterized by partially concurrent changes which includes growth acceleration, alteration in body composition and appearance of secondary sex characteristics. Puberty is characterized by an acceleration and then deceleration in skeletal growth. The initiation, duration and amount of growth vary considerably during the growth spurt. Pubertal growth and biological maturation are dynamic processes regulated by a variety of genetic and environmental factors. Changes in skeletal maturation and bone mineral accretion concomitant with the stage of pubertal development constitute essential components in the evaluation of growth during this pubertal period. Genetic, endocrine and nutritional factors and ethnicity contribute variably to the amount of growth gained during this important period of rapid changes. Many studies investigated the possibility of increasing pubertal growth to gain taller final adult height in adolescents with idiopathic short stature (ISS). The pattern of pubertal growth, its relation to sex maturity rating and factors affecting them has been addressed in this review. The results of different trials to increase final adult height of adolescents using different hormones have been summarized. These data enables Endocrinologists to give in-depth explanations to patients and families about the efficacy and clinical significance as well as the safety of using these therapies in the treatment of adolescents with ISS. PMID:25538878

DNA methyltransferase inhibitor CDA-II inhibits myogenic differentiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Zirong; Department of Molecular Genetics and Microbiology, Shands Cancer Center, University of Florida, Gainesville, FL 32610; Jin, Guorong

2012-06-08

Highlights: Black-Right-Pointing-Pointer CDA-II inhibits myogenic differentiation in a dose-dependent manner. Black-Right-Pointing-Pointer CDA-II repressed expression of muscle transcription factors and structural proteins. Black-Right-Pointing-Pointer CDA-II inhibited proliferation and migration of C2C12 myoblasts. -- Abstract: CDA-II (cell differentiation agent II), isolated from healthy human urine, is a DNA methyltransferase inhibitor. Previous studies indicated that CDA-II played important roles in the regulation of cell growth and certain differentiation processes. However, it has not been determined whether CDA-II affects skeletal myogenesis. In this study, we investigated effects of CDA-II treatment on skeletal muscle progenitor cell differentiation, migration and proliferation. We found that CDA-II blocked differentiationmore » of murine myoblasts C2C12 in a dose-dependent manner. CDA-II repressed expression of muscle transcription factors, such as Myogenin and Mef2c, and structural proteins, such as myosin heavy chain (Myh3), light chain (Mylpf) and MCK. Moreover, CDA-II inhibited C1C12 cell migration and proliferation. Thus, our data provide the first evidence that CDA-II inhibits growth and differentiation of muscle progenitor cells, suggesting that the use of CDA-II might affect skeletal muscle functions.« less

Intracellular processing of epidermal growth factor. I. Acidification of 125I-epidermal growth factor in intracellular organelles.

PubMed

Matrisian, L M; Planck, S R; Magun, B E

1984-03-10

We previously reported that 125I-labeled epidermal growth factor is processed intracellularly to acidic macromolecules in Rat-1 fibroblasts. The present study defines the precursor-product relationship and localization of the processing steps to subcellular organelles by the use of a single isoelectric species of 125I-epidermal growth factor and Percoll gradient fractionation. The native pI 4.55 125I-epidermal growth factor was rapidly processed to a pI 4.2 species on or near the cell surface and in organelles corresponding to clathrin-coated vesicles, Golgi, and endoplasmic reticulum. This species was then processed to a pI 4.35 species in similar organelles. The pI 4.2 and 4.35 species were converted to a pI 4.0 species in dense, lysosome-like organelles. This species was ultimately degraded and exocytosed from the cell as low molecular weight products.

The future of recombinant growth factors in wound healing.

PubMed

Robson, M C; Mustoe, T A; Hunt, T K

1998-08-01

For more than a decade, clinical trials have been conducted of the application of topical exogenous recombinant growth factors in attempts to accelerate the healing of chronic wounds. Although the results of some of these trials have been encouraging, overall the results have been somewhat discouraging. Much of the difficulty lies in the paucity of carefully controlled clinical trials of wound healing. Since wound healing is a complex process that can be influenced, both positively and negatively, by many factors, designing these trials has proved difficult. To date, only a single recombinant growth factor-recombinant human platelet-derived growth factor-BB (rhPDGF-BB)- has been approved by the US Food and Drug Administration; and that only for use in diabetic foot ulcers. It is unlikely, however, that a single growth factor will be able to resolve all issues of repair or strengthen all vulnerabilities of chronic wounds. Our expectation, therefore, is that growth factors, cytokines, and other biologic agents will be used more specifically in the future, for example, by targeting growth factor therapy at those specific components or processes that a given wound uses to heal.

Culture of prostate epithelial cells of the rhesus monkey on extracellular matrix substrate: influence of steroids and insulin-like growth factors.

PubMed

Udayakumar, T S; Jeyaraj, D A; Rajalakshmi, M; Sharma, R S

1999-09-01

Rhesus monkey prostate epithelial cells from the cranial lobe were isolated and cultured in flasks coated either with collagen IV or laminin. The effects of stromal cell medium, androgens and growth factors on cell number, thymidine incorporation and secretory activity were assessed. The results indicate that dihydrotestosterone (DHT) and androstenedione have stimulatory influences on cell proliferation and secretion in coated flasks. DHT was more effective in increasing cell number but the induction of secretory activity was similar with both steroids. The combination of IGF-I and -II resulted in inducing better cell proliferation and secretory activity than the individual IGFs but, of the two IGFs, IGF-I was more effective than IGF-II. DHT with IGFs was more potent in inducing proliferation, differentiation and secretion than androstenedione. Even in the absence of steroids or growth factors, colony formation and confluence occurred in coated flasks but cell differentiation and secretion only to a limited extent. In conclusion, we were able to establish an in vitro primary culture of prostate epithelial cells from rhesus monkey using extracellular matrix proteins, steroids and growth factors as additional supplements. This culture system may be useful to study prostate cell physiology and to identify drugs that can inhibit cell proliferation.

Proliferation of NS0 cells in protein-free medium: the role of cell-derived proteins, known growth factors and cellular receptors.

PubMed

Spens, Erika; Häggström, Lena

2009-05-20

NS0 cells proliferate without external supply of growth factors in protein-free media. We hypothesize that the cells produce their own factors to support proliferation. Understanding the mechanisms behind this autocrine regulation of proliferation may open for the novel approaches to improve animal cell processes. The following proteins were identified in NS0 conditioned medium (CM): cyclophilin A, cyclophilin B (CypB), cystatin C, D-dopachrome tautomerase, IL-25, isopentenyl-diphosphate delta-isomerase, macrophage migration inhibitory factor (MIF), beta(2)-microglobulin, Niemann pick type C2, secretory leukocyte protease inhibitor, thioredoxin-1, TNF-alpha, tumour protein translationally controlled 1 and ubiquitin. Further, cDNA microarray analysis indicated that the genes for IL-11, TNF receptor 6, TGF-beta receptor 1 and the IFN-gamma receptor were transcribed. CypB, IFN-alpha/beta/gamma, IL-11, IL-25, MIF, TGF-beta and TNF-alpha as well as the known growth factors EGF, IGF-I/II, IL-6, leukaemia inhibitory factor and oncostatin M (OSM) were excluded as involved in autocrine regulation of NS0 cell proliferation. The receptors for TGF-beta, IGF and OSM are however present in NS0 cell membranes since TGF-beta(1) caused cell death, and IGF-I/II and OSM improved cell growth. Even though no ligand was found, the receptor subunit gp130, active in signal transduction of the IL-6 like proteins, was shown to be essential for NS0 cells as demonstrated by siRNA gene silencing.

Type I and II Endometrial Cancers: Have They Different Risk Factors?

PubMed Central

Setiawan, Veronica Wendy; Yang, Hannah P.; Pike, Malcolm C.; McCann, Susan E.; Yu, Herbert; Xiang, Yong-Bing; Wolk, Alicja; Wentzensen, Nicolas; Weiss, Noel S.; Webb, Penelope M.; van den Brandt, Piet A.; van de Vijver, Koen; Thompson, Pamela J.; Strom, Brian L.; Spurdle, Amanda B.; Soslow, Robert A.; Shu, Xiao-ou; Schairer, Catherine; Sacerdote, Carlotta; Rohan, Thomas E.; Robien, Kim; Risch, Harvey A.; Ricceri, Fulvio; Rebbeck, Timothy R.; Rastogi, Radhai; Prescott, Jennifer; Polidoro, Silvia; Park, Yikyung; Olson, Sara H.; Moysich, Kirsten B.; Miller, Anthony B.; McCullough, Marjorie L.; Matsuno, Rayna K.; Magliocco, Anthony M.; Lurie, Galina; Lu, Lingeng; Lissowska, Jolanta; Liang, Xiaolin; Lacey, James V.; Kolonel, Laurence N.; Henderson, Brian E.; Hankinson, Susan E.; Håkansson, Niclas; Goodman, Marc T.; Gaudet, Mia M.; Garcia-Closas, Montserrat; Friedenreich, Christine M.; Freudenheim, Jo L.; Doherty, Jennifer; De Vivo, Immaculata; Courneya, Kerry S.; Cook, Linda S.; Chen, Chu; Cerhan, James R.; Cai, Hui; Brinton, Louise A.; Bernstein, Leslie; Anderson, Kristin E.; Anton-Culver, Hoda; Schouten, Leo J.; Horn-Ross, Pamela L.

2013-01-01

Purpose Endometrial cancers have long been divided into estrogen-dependent type I and the less common clinically aggressive estrogen-independent type II. Little is known about risk factors for type II tumors because most studies lack sufficient cases to study these much less common tumors separately. We examined whether so-called classical endometrial cancer risk factors also influence the risk of type II tumors. Patients and Methods Individual-level data from 10 cohort and 14 case-control studies from the Epidemiology of Endometrial Cancer Consortium were pooled. A total of 14,069 endometrial cancer cases and 35,312 controls were included. We classified endometrioid (n = 7,246), adenocarcinoma not otherwise specified (n = 4,830), and adenocarcinoma with squamous differentiation (n = 777) as type I tumors and serous (n = 508) and mixed cell (n = 346) as type II tumors. Results Parity, oral contraceptive use, cigarette smoking, age at menarche, and diabetes were associated with type I and type II tumors to similar extents. Body mass index, however, had a greater effect on type I tumors than on type II tumors: odds ratio (OR) per 2 kg/m2 increase was 1.20 (95% CI, 1.19 to 1.21) for type I and 1.12 (95% CI, 1.09 to 1.14) for type II tumors (Pheterogeneity < .0001). Risk factor patterns for high-grade endometrioid tumors and type II tumors were similar. Conclusion The results of this pooled analysis suggest that the two endometrial cancer types share many common etiologic factors. The etiology of type II tumors may, therefore, not be completely estrogen independent, as previously believed. PMID:23733771

Fibroblast Growth Factors and Vascular Endothelial Growth Factor Promote Cardiac Reprogramming under Defined Conditions.

PubMed

Yamakawa, Hiroyuki; Muraoka, Naoto; Miyamoto, Kazutaka; Sadahiro, Taketaro; Isomi, Mari; Haginiwa, Sho; Kojima, Hidenori; Umei, Tomohiko; Akiyama, Mizuha; Kuishi, Yuki; Kurokawa, Junko; Furukawa, Tetsushi; Fukuda, Keiichi; Ieda, Masaki

2015-12-08

Fibroblasts can be directly reprogrammed into cardiomyocyte-like cells (iCMs) by overexpression of cardiac transcription factors, including Gata4, Mef2c, and Tbx5; however, this process is inefficient under serum-based culture conditions, in which conversion of partially reprogrammed cells into fully reprogrammed functional iCMs has been a major hurdle. Here, we report that a combination of fibroblast growth factor (FGF) 2, FGF10, and vascular endothelial growth factor (VEGF), termed FFV, promoted cardiac reprogramming under defined serum-free conditions, increasing spontaneously beating iCMs by 100-fold compared with those under conventional serum-based conditions. Mechanistically, FFV activated multiple cardiac transcriptional regulators and converted partially reprogrammed cells into functional iCMs through the p38 mitogen-activated protein kinase and phosphoinositol 3-kinase/AKT pathways. Moreover, FFV enabled cardiac reprogramming with only Mef2c and Tbx5 through the induction of cardiac reprogramming factors, including Gata4. Thus, defined culture conditions promoted the quality of cardiac reprogramming, and this finding provides new insight into the mechanism of cardiac reprogramming. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Hepatocyte growth factor activator inhibitors (HAI-1 and HAI-2): Emerging key players in epithelial integrity and cancer.

PubMed

Kataoka, Hiroaki; Kawaguchi, Makiko; Fukushima, Tsuyoshi; Shimomura, Takeshi

2018-03-01

The growth, survival, and metabolic activities of multicellular organisms at the cellular level are regulated by intracellular signaling, systemic homeostasis and the pericellular microenvironment. Pericellular proteolysis has a crucial role in processing bioactive molecules in the microenvironment and thereby has profound effects on cellular functions. Hepatocyte growth factor activator inhibitor type 1 (HAI-1) and HAI-2 are type I transmembrane serine protease inhibitors expressed by most epithelial cells. They regulate the pericellular activities of circulating hepatocyte growth factor activator and cellular type II transmembrane serine proteases (TTSPs), proteases required for the activation of hepatocyte growth factor (HGF)/scatter factor (SF). Activated HGF/SF transduces pleiotropic signals through its receptor tyrosine kinase, MET (coded by the proto-oncogene MET), which are necessary for cellular migration, survival, growth and triggering stem cells for accelerated healing. HAI-1 and HAI-2 are also required for normal epithelial functions through regulation of TTSP-mediated activation of other proteases and protease-activated receptor 2, and also through suppressing excess degradation of epithelial junctional proteins. This review summarizes current knowledge regarding the mechanism of pericellular HGF/SF activation and highlights emerging roles of HAIs in epithelial development and integrity, as well as tumorigenesis and progression of transformed epithelial cells. © 2018 Japanese Society of Pathology and John Wiley & Sons Australia, Ltd.

Structural Variability of Tropospheric Growth Factors Transforming Mid-latitude Cyclones to Severe Storms over the North Atlantic

NASA Astrophysics Data System (ADS)

Wild, Simon; Befort, Daniel J.; Leckebusch, Gregor C.

2015-04-01

robustness of our preliminary results is generally dependent on the growth factor investigated, some examples include i) the overall availability of latent heat seems to be less important than its spatial structure around the cyclone core and ii) the variability of upper-tropospheric baroclinicity appears to be highest north of the surface position of the cyclone, especially for those that transform into a surface storm.

Localisation of stem cell factor, stanniocalcin-1, connective tissue growth factor and heparin-binding epidermal growth factor in the bovine uterus at the time of blastocyst formation.

PubMed

Muñoz, M; Martin, D; Carrocera, S; Alonso-Guervos, M; Mora, M I; Corrales, F J; Peynot, N; Giraud-Delville, C; Duranthon, V; Sandra, O; Gómez, E

2017-10-01

Early embryonic losses before implantation account for the highest rates of reproductive failure in mammals, in particular when in vitro-produced embryos are transferred. In the present study, we used molecular biology techniques (real-time quantitative polymerase chain reaction), classical immunohistochemical staining coupled with confocal microscopy and proteomic analysis (multiple reaction monitoring and western blot analysis) to investigate the role of four growth factors in embryo-uterine interactions during blastocyst development. Supported by a validated embryo transfer model, the study investigated: (1) the expression of stem cell factor (SCF), stanniocalcin-1 (STC1), connective tissue growth factor (CTGF) and heparin-binding epidermal growth factor-like growth factor (HB-EGF) in bovine uterine fluid; (2) the presence of SCF, STC1, CTGF and HB-EGF mRNA and protein in the bovine endometrium and embryos; and (3) the existence of reciprocal regulation between endometrial and embryonic expression of SCF, STC1, CTGF and HB-EGF. The results suggest that these growth factors most likely play an important role during preimplantation embryo development in cattle. The information obtained from the present study can contribute to improving the performance of in vitro culture technology in cattle and other species.

Targeting GH-1 splicing as a novel pharmacological strategy for growth hormone deficiency type II.

PubMed

Miletta, Maria Consolata; Flück, Christa E; Mullis, Primus-E

2017-01-15

Isolated growth hormone deficiency type II (IGHD II) is a rare genetic splicing disorder characterized by reduced growth hormone (GH) secretion and short stature. It is mainly caused by autosomal dominant-negative mutations within the growth hormone gene (GH-1) which results in missplicing at the mRNA level and the subsequent loss of exon 3, producing the 17.5-kDa GH isoform: a mutant and inactive GH protein that reduces the stability and the secretion of the 22-kDa GH isoform, the main biologically active GH form. At present, patients suffering from IGHD II are treated with daily injections of recombinant human GH (rhGH) in order to reach normal height. However, this type of replacement therapy, although effective in terms of growth, does not prevent the toxic effects of the 17.5-kDa mutant on the pituitary gland, which may eventually lead to other hormonal deficiencies. As the severity of the disease inversely correlates with the 17.5-kDa/22-kDa ratio, increasing the inclusion of exon 3 is expected to ameliorate disease symptoms. This review focuses on the recent advances in experimental and therapeutic strategies applicable to treat IGHD II in clinical and preclinical contexts. Several avenues for alternative IGHD II therapy will be discussed including the use of small interfering RNA (siRNA) and short hairpin RNA (shRNA) constructs that specifically target the exon 3-deleted transcripts as well as the application of histone deacetylase inhibitors (HDACi) and antisense oligonucleotides (AONs) to enhance full-length GH-1 transcription, correct GH-1 exon 3 splicing and manipulate GH pathway. Copyright © 2016 Elsevier Inc. All rights reserved.

Pro-tumorigenic effects of transforming growth factor beta 1 in canine osteosarcoma.

PubMed

Portela, R F; Fadl-Alla, B A; Pondenis, H C; Byrum, M L; Garrett, L D; Wycislo, K L; Borst, L B; Fan, T M

2014-01-01

Transforming growth factor beta 1 (TGFβ1) is a pleiotropic cytokine that contributes to reparative skeletal remodeling by inducing osteoblast proliferation, migration, and angiogenesis. Organic bone matrix is the largest bodily reservoir for latent TGFβ1, and active osteoblasts express cognate receptors for TGFβ1 (TGFβRI and TGFβRII). During malignant osteolysis, TGFβ1 is liberated from eroded bone matrix and promotes local progression of osteotropic solid tumors by its mitogenic and prosurvival activities. Canine osteosarcoma (OS) cells will possess TGFβ1 signaling machinery. Blockade of TGFβ1 signaling will attenuate pro-tumorigenic activities in OS cells. Naturally occurring primary OS samples will express cognate TGFβ1 receptors; and in dogs with OS, focal malignant osteolysis will contribute to circulating TGFβ1 concentrations. Thirty-three dogs with appendicular OS. Expression of TGFβ1 and its cognate receptors, as well as the biologic effects of TGFβ1 blockade, was characterized in OS cells. Ten spontaneous OS samples were characterized for TGFβRI/II expressions by immunohistochemistry. In 33 dogs with OS, plasma TGFβ1 concentrations were quantified and correlated with bone resorption. Canine OS cells secrete TGFβ1, express cognate receptors, and TGFβ1 signaling blockade decreases proliferation, migration, and vascular endothelial growth factor secretion. Naturally occurring OS samples abundantly and uniformly express TGFβRI/II, and in OS-bearing dogs, circulating TGFβ1 concentrations correlate with urine N-telopeptide excretion. Canine OS cells possess TGFβ1 signaling machinery, potentially allowing for the establishment of an autocrine and paracrine pro-tumorigenic signaling loop. As such, TGFβ1 inhibitors might impede localized OS progression in dogs. Copyright © 2014 by the American College of Veterinary Internal Medicine.

Temporal expression of growth factors triggered by epiregulin regulates inflammation development.

PubMed

Harada, Masaya; Kamimura, Daisuke; Arima, Yasunobu; Kohsaka, Hitoshi; Nakatsuji, Yuji; Nishida, Makoto; Atsumi, Toru; Meng, Jie; Bando, Hidenori; Singh, Rajeev; Sabharwal, Lavannya; Jiang, Jing-Jing; Kumai, Noriko; Miyasaka, Nobuyuki; Sakoda, Saburo; Yamauchi-Takihara, Keiko; Ogura, Hideki; Hirano, Toshio; Murakami, Masaaki

2015-02-01

In this study, we investigated the relationship between several growth factors and inflammation development. Serum concentrations of epiregulin, amphiregulin, betacellulin, TGF-α, fibroblast growth factor 2, placental growth factor (PLGF), and tenascin C were increased in rheumatoid arthritis patients. Furthermore, local blockades of these growth factors suppressed the development of cytokine-induced arthritis in mice by inhibiting chemokine and IL-6 expressions. We found that epiregulin expression was early and followed by the induction of other growth factors at different sites of the joints. The same growth factors then regulated the expression of epiregulin at later time points of the arthritis. These growth factors were increased in patients suffering from multiple sclerosis (MS) and also played a role in the development of an MS model, experimental autoimmune encephalomyelitis. The results suggest that the temporal expression of growth factors is involved in the inflammation development seen in several diseases, including rheumatoid arthritis and MS. Therefore, various growth factor pathways might be good therapeutic targets for various inflammatory diseases. Copyright © 2015 by The American Association of Immunologists, Inc.

Growth factor expression in cartilage wound healing: temporal and spatial immunolocalization in a rabbit auricular cartilage wound model.

PubMed

Bos, P K; van Osch, G J; Frenz, D A; Verhaar, J A; Verwoerd-Verhoef, H L

2001-05-01

The ability of cartilage to regenerate following injury is limited, potentially leading to osteoarthritis. Integrative cartilage repair, necessary for durable restoration of cartilage lesions, can be regarded as a wound healing process. Little is known about the effects of growth factors regulating acute cartilage wound healing in vivo. In this study the temporal expression patterns of growth factors and proteoglycan content in cartilage wound edges in vivo were studied. Cartilage wounds were created in rabbit ear cartilage using a 6 mm biopsy punch. Specimens were subsequently harvested 1, 3, 7, 14 and 28 days after surgery. Paraffin sections were thionin stained to visualize proteoglycan loss and replacement. Immunohistochemical staining of TGFbeta1, TGFbeta3, IGF-1, IGF-II and FGF-2 was used to define growth factor expression at the cartilage wound sites. Almost no effect of cartilage wounding was observed one day after surgery. A decrease of proteoglycan content, with a maximal loss at day 7, and a subsequent restoration was observed at the wound edges. Growth factor expression increased simultaneously. Maximal immunostaining for IGF1, IGFII, FGF2 and TGF-beta3 was observed at day 7, followed by a gradual decrease. Increased expression of TGFbeta1 lasted from day 3 until day 14. We have demonstrated the ability of chondrocytes to increase growth factor expression and to restore the rapid decrease in proteoglycan content in the initial phase following acute wounding. A temporal increase in intracellular growth factor expression suggests an autocrine and/or paracrine metabolic stimulation, which can be regarded a sign of chondrocytes repair capacity. Copyright 2001 OsteoArthritis Research Society International.

A role of placental growth factor in hair growth.

PubMed

Yoon, Sun-Young; Yoon, Ji-Seon; Jo, Seong Jin; Shin, Chang Yup; Shin, Jong-Yeon; Kim, Jong-Il; Kwon, Ohsang; Kim, Kyu Han

2014-05-01

The dermal papilla (DP) comprises specialized mesenchymal cells at the bottom of the hair follicle and plays a pivotal role in hair formation, anagen induction and the hair cycle. In this study, DPs were isolated from human hair follicles and serially subcultured. From each subculture at passages 1, 3, and 5 (n=4), we compared gene expression profiles using mRNA sequencing. Among the growth factors that were down-regulated in later passages of human DP cells (hDPCs), placental growth factor (PlGF) was selected. To elucidate the effect of PlGF on hair growth. We evaluated the effect of PlGF on hDPCs and on ex vivo hair organ culture. We investigated the effect of PlGF on an in vivo model of depilation-induced hair regeneration. We confirmed that the mRNA and protein expression levels of PlGF significantly decreased following subculture of the cells. It was shown that PlGF enhanced hair shaft elongation in ex vivo hair organ culture. Furthermore, PlGF significantly accelerated hair follicle growth and markedly prolonged anagen hair growth in an in vivo model of depilation-induced hair regeneration. PlGF prevented cell death by increasing the levels of phosphorylated extracellular signal-regulated kinase (ERK) and cyclin D1 and promoted survival by up-regulation of phosphorylated Akt and Bcl2, as determined by Western blotting. Our results suggest that PlGF plays a role in the promotion of hair growth and therefore may serve as an additional therapeutic target for the treatment of alopecia. Copyright © 2014 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

Examination of the Beck Depression Inventory-II Factor Structure Among Bariatric Surgery Candidates.

PubMed

Hayes, Sharon; Stoeckel, Nina; Napolitano, Melissa A; Collins, Charlotte; Wood, G Craig; Seiler, Jamie; Grunwald, Heidi E; Foster, Gary D; Still, Christopher D

2015-07-01

The Beck Depression Inventory-II (BDI-II) is frequently used to evaluate bariatric patients in clinical and research settings; yet, there are limited data regarding the factor structure of the BDI-II with a bariatric surgery population. Exploratory factor analysis (EFA) using principal axis factoring with oblimin rotation was employed with data from 1228 consecutive presurgical bariatric candidates. Independent t tests were used to examine potential differences between sexes. Confirmatory factor analysis (CFA) was conducted with the next 383 consecutive presurgical patients to evaluate the proposed model based on EFA results. EFA revealed three factors: negative perceptions, diminished vigor, and cognitive dysregulation, each with adequate internal consistency. Six BDI-II items did not load significantly on any of the three factors. CFA results largely supported the proposed model. Results suggest that dimensions of depression for presurgical bariatric candidates vary from other populations and raise important caveats regarding the utility of the BDI-II in bariatric research.

ESCRT-II controls retinal axon growth by regulating DCC receptor levels and local protein synthesis

PubMed Central

Konopacki, Filip A.; Dwivedy, Asha; Bellon, Anaïs; Blower, Michael D.

2016-01-01

Endocytosis and local protein synthesis (LPS) act coordinately to mediate the chemotropic responses of axons, but the link between these two processes is poorly understood. The endosomal sorting complex required for transport (ESCRT) is a key regulator of cargo sorting in the endocytic pathway, and here we have investigated the role of ESCRT-II, a critical ESCRT component, in Xenopus retinal ganglion cell (RGC) axons. We show that ESCRT-II is present in RGC axonal growth cones (GCs) where it co-localizes with endocytic vesicle GTPases and, unexpectedly, with the Netrin-1 receptor, deleted in colorectal cancer (DCC). ESCRT-II knockdown (KD) decreases endocytosis and, strikingly, reduces DCC in GCs and leads to axon growth and guidance defects. ESCRT-II-depleted axons fail to turn in response to a Netrin-1 gradient in vitro and many axons fail to exit the eye in vivo. These defects, similar to Netrin-1/DCC loss-of-function phenotypes, can be rescued in whole (in vitro) or in part (in vivo) by expressing DCC. In addition, ESCRT-II KD impairs LPS in GCs and live imaging reveals that ESCRT-II transports mRNAs in axons. Collectively, our results show that the ESCRT-II-mediated endocytic pathway regulates both DCC and LPS in the axonal compartment and suggest that ESCRT-II aids gradient sensing in GCs by coupling endocytosis to LPS. PMID:27248654

Subcutaneous administration of insulin-like growth factor (IGF)-II/IGF binding protein-2 complex stimulates bone formation and prevents loss of bone mineral density in a rat model of disuse osteoporosis

NASA Technical Reports Server (NTRS)

Conover, Cheryl A.; Johnstone, Edward W.; Turner, Russell T.; Evans, Glenda L.; John Ballard, F. John; Doran, Patrick M.; Khosla, Sundeep

2002-01-01

Elevated serum levels of insulin-like growth factor binding protein-2 (IGFBP-2) and a precursor form of IGF-II are associated with marked increases in bone formation and skeletal mass in patients with hepatitis C-associated osteosclerosis. In vitro studies indicate that IGF-II in complex with IGFBP-2 has high affinity for bone matrix and is able to stimulate osteoblast proliferation. The purpose of this study was to determine the ability of the IGF-II/IGFBP-2 complex to increase bone mass in vivo. Osteopenia of the femur was induced by unilateral sciatic neurectomy in rats. At the time of surgery, 14-day osmotic minipumps containing vehicle or 2 microg IGF-II+9 microg IGFBP-2/100g body weight/day were implanted subcutaneously in the neck. Bone mineral density (BMD) measurements were taken the day of surgery and 14 days later using a PIXImus small animal densitometer. Neurectomy of the right hindlimb resulted in a 9% decrease in right femur BMD (P<0.05 vs. baseline). This loss in BMD was completely prevented by treatment with IGF-II/IGFBP-2. On the control limb, there was no loss of BMD over the 14 days and IGF-II/IGFBP-2 treatment resulted in a 9% increase in left femur BMD (P<0.05). Bone histomorphometry indicated increases in endocortical and cancellous bone formation rates and in trabecular thickness. These results demonstrate that short-term administration of the IGF-II/IGFBP-2 complex can prevent loss of BMD associated with disuse osteoporosis and stimulate bone formation in adult rats. Furthermore, they provide proof of concept for a novel anabolic approach to increasing bone mass in humans with osteoporosis.

Growth Factors and Tension-Induced Skeletal Muscle Growth

NASA Technical Reports Server (NTRS)

Vandenburgh, Herman H.

1994-01-01

The project investigated biochemical mechanisms to enhance skeletal muscle growth, and developed a computer based mechanical cell stimulator system. The biochemicals investigated in this study were insulin/(Insulin like Growth Factor) IGF-1 and Steroids. In order to analyze which growth factors are essential for stretch-induced muscle growth in vitro, we developed a defined, serum-free medium in which the differentiated, cultured avian muscle fibers could be maintained for extended periods of time. The defined medium (muscle maintenance medium, MM medium) maintains the nitrogen balance of the myofibers for 3 to 7 days, based on myofiber diameter measurements and myosin heavy chain content. Insulin and IGF-1, but not IGF-2, induced pronounced myofiber hypertrophy when added to this medium. In 5 to 7 days, muscle fiber diameters increase by 71 % to 98% compared to untreated controls. Mechanical stimulation of the avian muscle fibers in MM medium increased the sensitivity of the cells to insulin and IGF-1, based on a leftward shift of the insulin dose/response curve for protein synthesis rates. (54). We developed a ligand binding assay for IGF-1 binding proteins and found that the avian skeletal muscle cultures produced three major species of 31, 36 and 43 kD molecular weight (54) Stretch of the myofibers was found to have no significant effect on the efflux of IGF-1 binding proteins, but addition of exogenous collagen stimulated IGF-1 binding protein production 1.5 to 5 fold. Steroid hormones have a profound effect on muscle protein turnover rates in vivo, with the stress-related glucocorticoids inducing rapid skeletal muscle atrophy while androgenic steroids induce skeletal muscle growth. Exercise in humans and animals reduces the catabolic effects of glucocorticoids and may enhance the anabolic effects of androgenic steroids on skeletal muscle. In our continuing work on the involvement of exogenrus growth factors in stretch-induced avian skeletal muscle growth, we

SPSB1, a Novel Negative Regulator of the Transforming Growth Factor-β Signaling Pathway Targeting the Type II Receptor.

PubMed

Liu, Sheng; Nheu, Thao; Luwor, Rodney; Nicholson, Sandra E; Zhu, Hong-Jian

2015-07-17

Appropriate cellular signaling is essential to control cell proliferation, differentiation, and cell death. Aberrant signaling can have devastating consequences and lead to disease states, including cancer. The transforming growth factor-β (TGF-β) signaling pathway is a prominent signaling pathway that has been tightly regulated in normal cells, whereas its deregulation strongly correlates with the progression of human cancers. The regulation of the TGF-β signaling pathway involves a variety of physiological regulators. Many of these molecules act to alter the activity of Smad proteins. In contrast, the number of molecules known to affect the TGF-β signaling pathway at the receptor level is relatively low, and there are no known direct modulators for the TGF-β type II receptor (TβRII). Here we identify SPSB1 (a Spry domain-containing Socs box protein) as a novel regulator of the TGF-β signaling pathway. SPSB1 negatively regulates the TGF-β signaling pathway through its interaction with both endogenous and overexpressed TβRII (and not TβRI) via its Spry domain. As such, TβRII and SPSB1 co-localize on the cell membrane. SPSB1 maintains TβRII at a low level by enhancing the ubiquitination levels and degradation rates of TβRII through its Socs box. More importantly, silencing SPSB1 by siRNA results in enhanced TGF-β signaling and migration and invasion of tumor cells. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

Histone deacetylase inhibitor belinostat represses survivin expression through reactivation of transforming growth factor beta (TGFbeta) receptor II leading to cancer cell death.

PubMed

Chowdhury, Sanjib; Howell, Gillian M; Teggart, Carol A; Chowdhury, Aparajita; Person, Jonathan J; Bowers, Dawn M; Brattain, Michael G

2011-09-02

Survivin is a cancer-associated gene that functions to promote cell survival, cell division, and angiogenesis and is a marker of poor prognosis. Histone deacetylase inhibitors induce apoptosis and re-expression of epigenetically silenced tumor suppressor genes in cancer cells. In association with increased expression of the tumor suppressor gene transforming growth factor β receptor II (TGFβRII) induced by the histone deacetylase inhibitor belinostat, we observed repressed survivin expression. We investigated the molecular mechanisms involved in survivin down-regulation by belinostat downstream of reactivation of TGFβ signaling. We identified two mechanisms. At early time points, survivin protein half-life was decreased with its proteasomal degradation. We observed that belinostat activated protein kinase A at early time points in a TGFβ signaling-dependent mechanism. After longer times (48 h), survivin mRNA was also decreased by belinostat. We made the novel observation that belinostat mediated cell death through the TGFβ/protein kinase A signaling pathway. Induction of TGFβRII with concomitant survivin repression may represent a significant mechanism in the anticancer effects of this drug. Therefore, patient populations exhibiting high survivin expression with epigenetically silenced TGFβRII might potentially benefit from the use of this histone deacetylase inhibitor.

Dual chain synthetic heparin-binding growth factor analogs

DOEpatents

Zamora, Paul O [Gaithersburg, MD; Pena, Louis A [Poquott, NY; Lin, Xinhua [Plainview, NY

2012-04-24

The invention provides synthetic heparin-binding growth factor analogs having two peptide chains each branched from a branch moiety, such as trifunctional amino acid residues, the branch moieties separated by a first linker of from 3 to about 20 backbone atoms, which peptide chains bind a heparin-binding growth factor receptor and are covalently bound to a non-signaling peptide that includes a heparin-binding domain, preferably by a second linker, which may be a hydrophobic second linker. The synthetic heparin-binding growth factor analogs are useful as pharmaceutical agents, soluble biologics or as surface coatings for medical devices.

Dual chain synthetic heparin-binding growth factor analogs

DOEpatents

Zamora, Paul O [Gaithersburg, MD; Pena, Louis A [Poquott, NY; Lin, Xinhua [Plainview, NY

2009-10-06

The invention provides synthetic heparin-binding growth factor analogs having two peptide chains each branched from a branch moiety, such as trifunctional amino acid residues, the branch moieties separated by a first linker of from 3 to about 20 backbone atoms, which peptide chains bind a heparin-binding growth factor receptor and are covalently bound to a non-signaling peptide that includes a heparin-binding domain, preferably by a second linker, which may be a hydrophobic second linker. The synthetic heparin-binding growth factor analogs are useful as pharmaceutical agents, soluble biologics or as surface coatings for medical devices.

Growth factors in urologic tissues: detection, characterization, and clinical applications.

PubMed

Mydlo, J H; Macchia, R J

1992-12-01

During the last two decades, enormous strides have been made in understanding cellular and molecular biology. The direction of treatment of many neoplasms and other diseases are starting at the microscopic level. Growth factors are polypeptides that play a part in the development and maintenance of living tissues. We, as well as others, have investigated the role that growth factors play particularly in urologic tissues, both benign and malignant. We review several well-known growth factors and their function in prostate, kidney, and bladder tissues, as well as their functions in other regulating processes of the human body, and also the use of growth factors as tumor markers, and antibodies to growth factors as possible treatment of disease.

Minoxidil Promotes Hair Growth through Stimulation of Growth Factor Release from Adipose-Derived Stem Cells

PubMed Central

Choi, Nahyun; Shin, Soyoung; Song, Sun U.; Sung, Jong-Hyuk

2018-01-01

Minoxidil directly promotes hair growth via the stimulation of dermal papilla (DP) and epithelial cells. Alternatively, there is little evidence for indirect promotion of hair growth via stimulation of adipose-derived stem cells (ASCs). We investigated whether minoxidil stimulates ASCs and if increased growth factor secretion by ASCs facilitates minoxidil-induced hair growth. Telogen-to-anagen induction was examined in mice. Cultured DP cells and vibrissae hair follicle organ cultures were used to further examine the underlying mechanisms. Subcutaneous injection of minoxidil-treated ASCs accelerated telogen-to-anagen transition in mice, and increased hair weight at day 14 post-injection. Minoxidil did not alter ASC proliferation, but increased migration and tube formation. Minoxidil also increased the secretion of growth factors from ASCs, including chemokine (C-X-C motif) ligand 1 (CXCL1), platelet-derived endothelial cell growth factor (PD-ECGF), and platelet-derived growth factor-C (PDGF-C). Minoxidil increased extracellular signal–regulated kinases 1/2 (ERK1/2) phosphorylation, and concomitant upregulation of PD-ECGF and PDGF-C mRNA levels were attenuated by an ERK inhibitor. Subcutaneous injection of CXCL1, PD-ECGF, or PDGF-C enhanced anagen induction in mice, and both CXCL1 and PDGF-C increased hair length in ex vivo organ culture. Treatment with CXCL1, PD-ECGF, or PDGF-C also increased the proliferation index in DP cells. Finally, topical application of CXCL1, PD-ECGF, or PDGF-C with 2% minoxidil enhanced anagen induction when compared to minoxidil alone. Minoxidil stimulates ASC motility and increases paracrine growth factor signaling. Minoxidil-stimulated secretion of growth factors by ASCs may enhance hair growth by promoting DP proliferation. Therefore, minoxidil can be used as an ASC preconditioning agent for hair regeneration. PMID:29495622

Minoxidil Promotes Hair Growth through Stimulation of Growth Factor Release from Adipose-Derived Stem Cells.

PubMed

Choi, Nahyun; Shin, Soyoung; Song, Sun U; Sung, Jong-Hyuk

2018-02-28

Minoxidil directly promotes hair growth via the stimulation of dermal papilla (DP) and epithelial cells. Alternatively, there is little evidence for indirect promotion of hair growth via stimulation of adipose-derived stem cells (ASCs). We investigated whether minoxidil stimulates ASCs and if increased growth factor secretion by ASCs facilitates minoxidil-induced hair growth. Telogen-to-anagen induction was examined in mice. Cultured DP cells and vibrissae hair follicle organ cultures were used to further examine the underlying mechanisms. Subcutaneous injection of minoxidil-treated ASCs accelerated telogen-to-anagen transition in mice, and increased hair weight at day 14 post-injection. Minoxidil did not alter ASC proliferation, but increased migration and tube formation. Minoxidil also increased the secretion of growth factors from ASCs, including chemokine (C-X-C motif) ligand 1 (CXCL1), platelet-derived endothelial cell growth factor (PD-ECGF), and platelet-derived growth factor-C (PDGF-C). Minoxidil increased extracellular signal-regulated kinases 1/2 (ERK1/2) phosphorylation, and concomitant upregulation of PD-ECGF and PDGF-C mRNA levels were attenuated by an ERK inhibitor. Subcutaneous injection of CXCL1, PD-ECGF, or PDGF-C enhanced anagen induction in mice, and both CXCL1 and PDGF-C increased hair length in ex vivo organ culture. Treatment with CXCL1, PD-ECGF, or PDGF-C also increased the proliferation index in DP cells. Finally, topical application of CXCL1, PD-ECGF, or PDGF-C with 2% minoxidil enhanced anagen induction when compared to minoxidil alone. Minoxidil stimulates ASC motility and increases paracrine growth factor signaling. Minoxidil-stimulated secretion of growth factors by ASCs may enhance hair growth by promoting DP proliferation. Therefore, minoxidil can be used as an ASC preconditioning agent for hair regeneration.

Genetic factors in fetal growth restriction and miscarriage.

PubMed

Yamada, Hideto; Sata, Fumihiro; Saijo, Yasuaki; Kishi, Reiko; Minakami, Hisanori

2005-06-01

Recently, several investigations concerning disadvantageous genetic factors in human reproduction have progressed. Inherited thrombophilia, such as factor V Leiden, prothrombin, and methylenetetrahydrofolate reductase mutations; gene polymorphisms of detoxification enzyme (CYP1A1); growth factors (insulin-like growth factor-I); and hormones such as angiotensinogen and CYP17 are involved in the pathogenesis of fetal growth restriction. The inherited thrombophilia, gene polymorphisms of coagulation and anticoagulation factor such as thrombomodulin, endothelial protein C receptor, plasminogen activator inhibitor 1, and factor XIII; human lymphocyte antigen (HLA-G); detoxification enzymes (glutathione- S-transferase M1); cytokines such as interleukin (IL) -1 and IL-6; hormones (CYP17); vasodilators (nitric oxide synthase 3); and vitamins (transcobalamin) are involved in the pathogenesis of sporadic and recurrent miscarriage. It is likely that a gene polymorphism or mutation susceptible to reproductive failure has a beneficial effect on the process of human reproduction with or without the environmental interaction. The factor V Leiden mutation has genetic advantages that are believed to be an improved implantation rate in in vitro fertilization and a reduction of maternal intrapartum blood loss. It has also been demonstrated that the CYP17 A2 allele has bidirectional effects on human reproduction, including increases in susceptibility to recurrent miscarriage and fetal growth enhancement.

Controlled growth factor release from synthetic extracellular matrices

NASA Astrophysics Data System (ADS)

Lee, Kuen Yong; Peters, Martin C.; Anderson, Kenneth W.; Mooney, David J.

2000-12-01

Polymeric matrices can be used to grow new tissues and organs, and the delivery of growth factors from these matrices is one method to regenerate tissues. A problem with engineering tissues that exist in a mechanically dynamic environment, such as bone, muscle and blood vessels, is that most drug delivery systems have been designed to operate under static conditions. We thought that polymeric matrices, which release growth factors in response to mechanical signals, might provide a new approach to guide tissue formation in mechanically stressed environments. Critical design features for this type of system include the ability to undergo repeated deformation, and a reversible binding of the protein growth factors to polymeric matrices to allow for responses to repeated stimuli. Here we report a model delivery system that can respond to mechanical signalling and upregulate the release of a growth factor to promote blood vessel formation. This approach may find a number of applications, including regeneration and engineering of new tissues and more general drug-delivery applications.

Heterogeneity for IGF-II production maintained by public goods dynamics in neuroendocrine pancreatic cancer.

PubMed

Archetti, Marco; Ferraro, Daniela A; Christofori, Gerhard

2015-02-10

The extensive intratumor heterogeneity revealed by sequencing cancer genomes is an essential determinant of tumor progression, diagnosis, and treatment. What maintains heterogeneity remains an open question because competition within a tumor leads to a strong selection for the fittest subclone. Cancer cells also cooperate by sharing molecules with paracrine effects, such as growth factors, and heterogeneity can be maintained if subclones depend on each other for survival. Without strict interdependence between subclones, however, nonproducer cells can free-ride on the growth factors produced by neighboring producer cells, a collective action problem known in game theory as the "tragedy of the commons," which has been observed in microbial cell populations. Here, we report that similar dynamics occur in cancer cell populations. Neuroendocrine pancreatic cancer (insulinoma) cells that do not produce insulin-like growth factor II (IGF-II) grow slowly in pure cultures but have a proliferation advantage in mixed cultures, where they can use the IGF-II provided by producer cells. We show that, as predicted by evolutionary game theory, producer cells do not go extinct because IGF-II acts as a nonlinear public good, creating negative frequency-dependent selection that leads to a stable coexistence of the two cell types. Intratumor cell heterogeneity can therefore be maintained even without strict interdependence between cell subclones. Reducing the amount of growth factors available within a tumor may lead to a reduction in growth followed by a new equilibrium, which may explain relapse in therapies that target growth factors.

Transforming growth factor-alpha short-circuits downregulation of the epidermal growth factor receptor.

PubMed

Ouyang, X; Gulliford, T; Huang, G; Epstein, R J

1999-04-01

Transforming growth factor-alpha (TGFalpha) is an epidermal growth factor receptor (EGFR) ligand which is distinguished from EGF by its acid-labile structure and potent transforming function. We recently reported that TGFalpha induces less efficient EGFR heterodimerization and downregulation than does EGF (Gulliford et al., 1997, Oncogene, 15:2219-2223). Here we use isoform-specific EGFR and ErbB2 antibodies to show that the duration of EGFR signalling induced by a single TGFalpha exposure is less than that induced by equimolar EGF. The protein trafficking inhibitor brefeldin A (BFA) reduces the duration of EGF signalling to an extent similar to that seen with TGFalpha alone; the effects of TGFalpha and BFA on EGFR degradation are opposite, however, with TGFalpha sparing EGFR from downregulation but BFA accelerating EGF-dependent receptor loss. This suggests that BFA blocks EGFR recycling and thus shortens EGF-dependent receptor signalling, whereas TGFalpha shortens receptor signalling and thus blocks EGFR downregulation. Consistent with this, repeated application of TGFalpha is accompanied by prolonged EGFR expression and signalling, whereas similar application of EGF causes receptor downregulation and signal termination. These findings indicate that constitutive secretion of pH-labile TGFalpha may perpetuate EGFR signalling by permitting early oligomer dissociation and dephosphorylation within acidic endosomes, thereby extinguishing a phosphotyrosine-based downregulation signal and creating an irreversible autocrine growth loop.

Fibroblast Growth Factor 2-A Predictor of Outcome for Patients Irradiated for Stage II-III Non-Small-Cell Lung Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rades, Dirk, E-mail: Rades.Dirk@gmx.net; Setter, Cornelia; Dahl, Olav

2012-01-01

Purpose: The prognostic value of the tumor cell expression of the fibroblast growth factor 2 (FGF-2) in patients with non-small-cell lung cancer (NSCLC) is unclear. The present study investigated the effect of tumor cell expression of FGF-2 on the outcome of 60 patients irradiated for Stage II-III NSCLC. Methods and Materials: The effect of FGF-2 expression and 13 additional factors on locoregional control (LRC), metastasis-free survival (MFS), and overall survival (OS) were retrospectively evaluated. These additional factors included age, gender, Karnofsky performance status, histologic type, histologic grade, T and N category, American Joint Committee on Cancer stage, surgery, chemotherapy, pack-years,more » smoking during radiotherapy, and hemoglobin during radiotherapy. Locoregional failure was identified by endoscopy or computed tomography. Univariate analyses were performed with the Kaplan-Meier method and the Wilcoxon test and multivariate analyses with the Cox proportional hazard model. Results: On univariate analysis, improved LRC was associated with surgery (p = .017), greater hemoglobin levels (p = .036), and FGF-2 negativity (p <.001). On multivariate analysis of LRC, surgery (relative risk [RR], 2.44; p = .037), and FGF-2 expression (RR, 5.06; p <.001) maintained significance. On univariate analysis, improved MFS was associated with squamous cell carcinoma (p = .020), greater hemoglobin levels (p = .007), and FGF-2 negativity (p = .001). On multivariate analysis of MFS, the hemoglobin levels (RR, 2.65; p = .019) and FGF-2 expression (RR, 3.05; p = .004) were significant. On univariate analysis, improved OS was associated with a lower N category (p = .048), greater hemoglobin levels (p <.001), and FGF-2 negativity (p <.001). On multivariate analysis of OS, greater hemoglobin levels (RR, 4.62; p = .002) and FGF-2 expression (RR, 3.25; p = .002) maintained significance. Conclusions: Tumor cell expression of FGF-2 appeared to be an independent negative

Extracellular matrix and growth factors in branching morphogenesis

NASA Technical Reports Server (NTRS)

Hardman, P.; Spooner, B. S.

1993-01-01

The unifying hypothesis of the NSCORT in gravitational biology postulates that the ECM and growth factors are key interrelated components of a macromolecular regulatory system. The ECM is known to be important in growth and branching morphogenesis of embryonic organs. Growth factors have been detected in the developing embryo, and often the pattern of localization is associated with areas undergoing epithelial-mesenchymal interactions. Causal relationships between these components may be of fundamental importance in control of branching morphogenesis.

Epidermal Growth Factor Receptor Transactivation: Mechanisms, Pathophysiology, and Potential Therapies in the Cardiovascular System.

PubMed

Forrester, Steven J; Kawai, Tatsuo; O'Brien, Shannon; Thomas, Walter; Harris, Raymond C; Eguchi, Satoru

2016-01-01

Epidermal growth factor receptor (EGFR) activation impacts the physiology and pathophysiology of the cardiovascular system, and inhibition of EGFR activity is emerging as a potential therapeutic strategy to treat diseases including hypertension, cardiac hypertrophy, renal fibrosis, and abdominal aortic aneurysm. The capacity of G protein-coupled receptor (GPCR) agonists, such as angiotensin II (AngII), to promote EGFR signaling is called transactivation and is well described, yet delineating the molecular processes and functional relevance of this crosstalk has been challenging. Moreover, these critical findings are dispersed among many different fields. The aim of our review is to highlight recent advancements in defining the signaling cascades and downstream consequences of EGFR transactivation in the cardiovascular renal system. We also focus on studies that link EGFR transactivation to animal models of the disease, and we discuss potential therapeutic applications.

Evidences for involvement of growth hormone and insulin-like growth factor in ovarian development of starry flounder (Platichthys stellatus).

PubMed

Xu, Yongjiang; Wang, Bin; Liu, Xuezhou; Shi, Bao; Zang, Kun

2017-04-01

Although gonadotrophins are major regulators of ovarian function in teleosts and other vertebrates, accumulating evidence indicates that the growth hormone (GH)-insulin-like growth factor (IGF) axis also plays an important role in fish reproduction. As a first step to understand the physiological role of the GH-IGF system in the ovarian development of starry flounder (Platichthys stellatus), the expression profiles of GH and IGF messenger RNAs (mRNAs) and plasma GH, IGF-I, estradiol-17β (E2), and testosterone (T) levels during the ovarian development were investigated. The developmental stages of ovaries were divided into five stages (II, III, IV, V, and VI) by histological analysis. The hepatosomatic index (HSI) and gonadosomatic index (GSI) values increased and peaked at stage IV and stage V, respectively, and then declined at stage VI. Pituitary GH mRNA levels decreased sharply at stage III and raised to top level at stage VI. The hepatic IGF-I mRNA levels ascended to maximum value at stage V and then declined significantly at stage VI. However, the hepatic IGF-II mRNA levels remained stable and increased significantly at stage VI. In contrast, the ovarian IGF-I mRNA levels increased gradually and peaked at stage VI. The ovarian IGF-II mRNA levels were initially stable and increased significantly at stage V until the top level at stage VI. Consistent with the pituitary GH mRNA levels, plasma GH levels reduced sharply at stage III and remained depressed until stage V and then raised remarkably at stage VI. Plasma IGF-I level peaked at stage V and then declined to initial level. Plasma E2 level peaked at stage IV and then dramatically descended to the basal level. Plasma T level peaked at stage V and then declined significantly back to the basal level. Based on statistical analysis, significant positive correlations between hepatic IGF-I mRNA and GSI, ovarian IGF-II mRNA and hepatic IGF-II mRNA, ovarian IGF-I mRNA and ovarian IGF-II mRNA, and plasma IGF-I and

Growth and Growth hormone - Insulin Like Growth Factor -I (GH-IGF-I) Axis in Chronic Anemias.

PubMed

Soliman, Ashraf T; De Sanctis, Vincenzo; Yassin, Mohamed; Adel, Ashraf

2017-04-28

Anaemia is a global public health problem affecting both developing and developed countries with major consequences for human health as well as social and economic development. It occurs at all stages of the life cycle, but is more prevalent in pregnant women and young children. Iron deficiency anaemia (IDA) was considered to be among the most important contributing factors to the global burden of disease. Prolonged and/or chronic anemia has a negative effect on linear growth especially during the rapid phases (infancy and puberty). Additionally infants with chronic IDA have delayed cognitive, motor, and affective development that may be long-lasting. In view of the significant impact of chronic anemias on growth, pediatricians endocrinologists and hematologists should advocate primary prevention and screening for growth disturbance in these forms of anemias. The extent of the negative effect of different forms of chronic anemias on linear growth and its possible reversibilty is addressed in this review. The possible mechanisms that may impair growth in the different forms of anemias are addressed with special attention to their effect on the growth hormone (GH) - insulin like growth factor -I (IGF-I).

Fibroblast Growth Factors Stimulate Hair Growth through β-Catenin and Shh Expression in C57BL/6 Mice

PubMed Central

Lin, Wei-hong; Xiang, Li-Jun; Shi, Hong-Xue; Zhang, Jian; Jiang, Li-ping; Cai, Ping-tao; Lin, Zhen-Lang; Lin, Bei-Bei; Huang, Yan; Zhang, Hai-Lin; Fu, Xiao-Bing; Guo, Ding-Jiong; Li, Xiao-Kun; Wang, Xiao-Jie; Xiao, Jian

2015-01-01

Growth factors are involved in the regulation of hair morphogenesis and cycle hair growth. The present study sought to investigate the hair growth promoting activities of three approved growth factor drugs, fibroblast growth factor 10 (FGF-10), acidic fibroblast growth factor (FGF-1), and basic fibroblast growth factor (FGF-2), and the mechanism of action. We observed that FGFs promoted hair growth by inducing the anagen phase in telogenic C57BL/6 mice. Specifically, the histomorphometric analysis data indicates that topical application of FGFs induced an earlier anagen phase and prolonged the mature anagen phase, in contrast to the control group. Moreover, the immunohistochemical analysis reveals earlier induction of β-catenin and Sonic hedgehog (Shh) in hair follicles of the FGFs-treated group. These results suggest that FGFs promote hair growth by inducing the anagen phase in resting hair follicles and might be a potential hair growth-promoting agent. PMID:25685806

Effect of growth factors on hyaluronan production by canine vocal fold fibroblasts.

PubMed

Hirano, Shigeru; Bless, Diane M; Heisey, Dennis; Ford, Charles N

2003-07-01

Hyaluronan (HYA) is considered to be a crucial factor in scarless wound healing and in maintaining tissue viscosity of the vocal fold lamina propria. In this study focusing on the effects of growth factors, we examined how HYA is produced and controlled in canine cultured vocal fold fibroblasts. Fibroblasts were taken from the lamina propria of the vocal folds of 8 dogs and cultured with and without growth factors. The production of HYA in the supernatant culture was quantitatively examined by enzyme-linked immunosorbent assay. Hepatocyte growth factor, epidermal growth factor, basic fibroblast growth factor, and transforming growth factor beta1 all stimulated HYA synthesis from vocal fold fibroblasts. These effects differed with the concentration of growth factors and the incubation period. We also examined how frequently the growth factors had to be administered in order to maintain appropriate levels of HYA. A single administration was sufficient to maintain appropriate HYA levels for at least 7 days. The present studies have demonstrated positive effects of growth factors in stimulating HYA production. Further in vivo study is needed to clarify the usefulness of these growth factors in the management of vocal fold scarring.

Friends Turned Foes: Angiogenic Growth Factors beyond Angiogenesis.

PubMed

Matkar, Pratiek N; Ariyagunarajah, Ramya; Leong-Poi, Howard; Singh, Krishna K

2017-10-02

Angiogenesis, the formation of new blood vessels from pre-existing ones is a biological process that ensures an adequate blood flow is maintained to provide the cells with a sufficient supply of nutrients and oxygen within the body. Numerous soluble growth factors and inhibitors, cytokines, proteases as well as extracellular matrix proteins and adhesion molecules stringently regulate the multi-factorial process of angiogenesis. The properties and interactions of key angiogenic molecules such as vascular endothelial growth factors (VEGFs), fibroblast growth factors (FGFs) and angiopoietins have been investigated in great detail with respect to their molecular impact on angiogenesis. Since the discovery of angiogenic growth factors, much research has been focused on their biological actions and their potential use as therapeutic targets for angiogenic or anti-angiogenic strategies in a context-dependent manner depending on the pathologies. It is generally accepted that these factors play an indispensable role in angiogenesis. However, it is becoming increasingly evident that this is not their only role and it is likely that the angiogenic factors have important functions in a wider range of biological and pathological processes. The additional roles played by these molecules in numerous pathologies and biological processes beyond angiogenesis are discussed in this review.

Friends Turned Foes: Angiogenic Growth Factors beyond Angiogenesis

PubMed Central

Matkar, Pratiek N.; Ariyagunarajah, Ramya; Leong-Poi, Howard; Singh, Krishna K.

2017-01-01

Angiogenesis, the formation of new blood vessels from pre-existing ones is a biological process that ensures an adequate blood flow is maintained to provide the cells with a sufficient supply of nutrients and oxygen within the body. Numerous soluble growth factors and inhibitors, cytokines, proteases as well as extracellular matrix proteins and adhesion molecules stringently regulate the multi-factorial process of angiogenesis. The properties and interactions of key angiogenic molecules such as vascular endothelial growth factors (VEGFs), fibroblast growth factors (FGFs) and angiopoietins have been investigated in great detail with respect to their molecular impact on angiogenesis. Since the discovery of angiogenic growth factors, much research has been focused on their biological actions and their potential use as therapeutic targets for angiogenic or anti-angiogenic strategies in a context-dependent manner depending on the pathologies. It is generally accepted that these factors play an indispensable role in angiogenesis. However, it is becoming increasingly evident that this is not their only role and it is likely that the angiogenic factors have important functions in a wider range of biological and pathological processes. The additional roles played by these molecules in numerous pathologies and biological processes beyond angiogenesis are discussed in this review. PMID:28974056

Alterations of Growth Factors in Autism and Attention-Deficit/Hyperactivity Disorder

PubMed Central

Galvez-Contreras, Alma Y.; Campos-Ordonez, Tania; Gonzalez-Castaneda, Rocio E.; Gonzalez-Perez, Oscar

2017-01-01

Growth factors (GFs) are cytokines that regulate the neural development. Recent evidence indicates that alterations in the expression level of GFs during embryogenesis are linked to the pathophysiology and clinical manifestations of attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorders (ASD). In this concise review, we summarize the current evidence that supports the role of brain-derived neurotrophic factor, insulin-like growth factor 2, hepatocyte growth factor (HGF), glial-derived neurotrophic factor, nerve growth factor, neurotrophins 3 and 4, and epidermal growth factor in the pathogenesis of ADHD and ASD. We also highlight the potential use of these GFs as clinical markers for diagnosis and prognosis of these neurodevelopmental disorders. PMID:28751869

Phytoplankton growth and PSII efficiency sensitivity to a glyphosate-based herbicide (Factor 540®).

PubMed

Smedbol, Élise; Lucotte, Marc; Labrecque, Michel; Lepage, Laurent; Juneau, Philippe

2017-11-01

The use of glyphosate-based herbicides in agriculture has increased steadily since the mid 90's and there is now evidence of glyphosate leaching and contamination of aquatic ecosystems. The aim of this study was to evaluate the effects of a glyphosate-based herbicide (Factor 540 ® ) on growth and photosynthetic capacity of algae and cyanobacteria. Six algal and three cyanobacterial species/strains, of three different taxonomic groups, were exposed to five glyphosate concentrations (10, 50, 100, 500 and 1000μgl -1 ) during 48h. All species have significant growth inhibition at concentrations varying between 50 and 500μgl -1 . The photosynthetic response, after glyphosate exposure, varied among species, but a general pattern has emerged. There was an increase in the amount of photons absorbed (ABS/RC), in dissipated (DI O /RC) and trapped (TR O /RC) energy in the photosystem II reaction centers, along with a decreased of the maximum photosystem II quantum yield (F V /F M ) and electron transport per reaction center (ET O /RC). The EC 50 and LOEC values for growth and photosynthesis were calculated and established that growth was the most affected parameter by glyphosate-based herbicide, while parameter TR O /RC was the least affected. All species showed reduced growth at glyphosate concentrations lower than the Canadian standard for the protection of aquatic life, set at 800μgl -1 or the American aquatic life benchmark for acute toxicity in non vascular plants of 12 100μgl -1 questioning the validity of these thresholds in assessing the risks related to the presence of glyphosate and glyphosate-based herbicides in aquatic systems. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

Epidermal growth factor in alkali-burned corneal epithelial wound healing.

PubMed

Singh, G; Foster, C S

1987-06-15

We conducted a double-masked study to evaluate the effect of epidermal growth factor on epithelial wound healing and recurrent erosions in alkali-burned rabbit corneas. Epithelial wounds 10 mm in diameter healed completely under the influence of topical epidermal growth factor, whereas the control corneas did not resurface in the center. On reversal of treatment, the previously nonhealing epithelial defects healed when treated with topical epidermal growth factor eyedrops. Conversely, the epidermal growth factor-treated and resurfaced corneas developed epithelial defects when treatment was discontinued. Histopathologic examination disclosed hyperplastic epithelium growing over the damaged stroma laden with polymorphonuclear leukocytes when treated with epidermal growth factor eyedrops, but it did not adhere to the underlying tissue. Hydropic changes were seen intracellularly as well as between the epithelial cells and the stroma.

Human corpus luteum: presence of epidermal growth factor receptors and binding characteristics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ayyagari, R.R.; Khan-Dawood, F.S.

Epidermal growth factor receptors are present in many reproductive tissues but have not been demonstrated in the human corpus luteum. To determine the presence of epidermal growth factor receptors and its binding characteristics, we carried out studies on the plasma cell membrane fraction of seven human corpora lutea (days 16 to 25) of the menstrual cycle. Specific epidermal growth factor receptors were present in human corpus luteum. Insulin, nerve growth factor, and human chorionic gonadotropin did not competitively displace epidermal growth factor binding. The optimal conditions for corpus luteum-epidermal growth factor receptor binding were found to be incubation for 2more » hours at 4 degrees C with 500 micrograms plasma membrane protein and 140 femtomol /sup 125/I-epidermal growth factor per incubate. The number (mean +/- SEM) of epidermal growth factor binding sites was 12.34 +/- 2.99 X 10(-19) mol/micrograms protein; the dissociation constant was 2.26 +/- 0.56 X 10(-9) mol/L; the association constant was 0.59 +/- 0.12 X 10(9) L/mol. In two regressing corpora lutea obtained on days 2 and 3 of the menstrual cycle, there was no detectable specific epidermal growth factor receptor binding activity. Similarly no epidermal growth factor receptor binding activity could be detected in ovarian stromal tissue. Our findings demonstrate that specific receptors for epidermal growth factor are present in the human corpus luteum. The physiologic significance of epidermal growth factor receptors in human corpus luteum is unknown, but epidermal growth factor may be involved in intragonadal regulation of luteal function.« less

Higher Maternal Protein Intake during Pregnancy Is Associated with Lower Cord Blood Concentrations of Insulin-like Growth Factor (IGF)-II, IGF Binding Protein 3, and Insulin, but Not IGF-I, in a Cohort of Women with High Protein Intake.

PubMed

Switkowski, Karen M; Jacques, Paul F; Must, Aviva; Hivert, Marie-France; Fleisch, Abby; Gillman, Matthew W; Rifas-Shiman, Sheryl; Oken, Emily

2017-07-01

Background: Prenatal exposure to dietary protein may program growth-regulating hormones, consequently influencing early-life growth patterns and later risk of associated chronic diseases. The insulin-like growth factor (IGF) axis is of particular interest in this context given its influence on pre- and postnatal growth and its sensitivity to the early nutritional environment. Objective: Our objective was to examine associations of maternal protein intake during pregnancy with cord blood concentrations of IGF-I, IGF-II, IGF binding protein-3 (IGFBP-3), and insulin. Methods: We studied 938 mother-child pairs from early pregnancy through delivery in the Project Viva cohort. Using multivariable linear regression models adjusted for maternal race/ethnicity, education, income, smoking, parity, height, and gestational weight gain and for child sex, we examined associations of second-trimester maternal protein intake [grams per kilogram (weight before pregnancy) per day], as reported on a food frequency questionnaire, with IGF-I, IGF-II, IGFBP-3, and insulin concentrations in cord blood. We also examined how these associations may differ by child sex and parity. Results: Mothers were predominantly white (71%), college-educated (64%), and nonsmokers (67%). Mean ± SD protein intake was 1.35 ± 0.35 g ⋅ kg -1 ⋅ d -1 Each 1-SD increment in second-trimester protein intake corresponded to a change of -0.50 ng/mL (95% CI: -2.26, 1.26 ng/mL) in IGF-I and -0.91 μU/mL (95% CI: -1.45, -0.37 μU/mL) in insulin. Child sex and parity modified associations of maternal protein intake with IGF-II and IGFBP-3: protein intake was inversely associated with IGF-II in girls ( P -interaction = 0.04) and multiparous mothers ( P -interaction = 0.05), and with IGFBP-3 in multiparous mothers ( P -interaction = 0.04). Conclusions: In a cohort of pregnant women with relatively high mean protein intakes, higher intake was associated with lower concentrations of growth-promoting hormones in cord

Association of Angiotensin Converting Enzyme I/D and α-actinin-3 R577X Genotypes with Growth Factors and Physical Fitness in Korean Children

PubMed Central

Ahn, Nayoung; Cheun, Wookwang; Byun, Jayoung; Joo, Youngsik

2015-01-01

This study analyzed the differences in aerobic and anaerobic exercise ability and growth-related indicators, depending on the polymorphism of the ACE and the ACTN3 genes, to understand the genetic influence of exercise ability in the growth process of children. The subjects of the study consisted of elementary school students (n=856, age 10.32±0.07 yr). The anthropometric parameters, physical fitness and growth factors were compared among groups of the ACE I/D or the ACTN3 R577X polymorphisms. There were no significant differences between the anthropometric parameters, physical fitness and growth factors for the ACE gene ID or the ACTN3 gene R577X polymorphism. However, the DD type of ACE gene was highest in the side step test (p<0.05), and the DD type was significantly higher than the II+ID type (p<0.05) in the early bone age. The combined group of the ACE gene II+ID and the ACTN3 gene XX type significantly showed lower early bone age (p< 0.05). This study did not find any individual or compounding effects of the polymorphism in the ACE I/D or the ACTN3 R577X polymorphisms on the anthropometric parameters, physical fitness and growth factors of Korean children. However, the exercise experience and the DD type of the ACE gene may affect the early maturity of the bones. PMID:25729275

Predictive factors for intrauterine growth restriction.

PubMed

Albu, A R; Anca, A F; Horhoianu, V V; Horhoianu, I A

2014-06-15

Reduced fetal growth is seen in about 10% of the pregnancies but only a minority has a pathological background and is known as intrauterine growth restriction or fetal growth restriction (IUGR / FGR). Increased fetal and neonatal mortality and morbidity as well as adult pathologic conditions are often associated to IUGR. Risk factors for IUGR are easy to assess but have poor predictive value. For the diagnostic purpose, biochemical serum markers, ultrasound and Doppler study of uterine and spiral arteries, placental volume and vascularization, first trimester growth pattern are object of assessment today. Modern evaluations propose combined algorithms using these strategies, all with the goal of a better prediction of risk pregnancies.

Ocular Angiogenesis: Vascular Endothelial Growth Factor and Other Factors.

PubMed

Rubio, Roman G; Adamis, Anthony P

2016-01-01

Systematic study of the mechanisms underlying pathological ocular neovascularization has yielded a wealth of knowledge about pro- and anti-angiogenic factors that modulate diseases such as neovascular age-related macular degeneration. The evidence implicating vascular endothelial growth factor (VEGF) in particular has led to the development of a number of approved anti-VEGF therapies. Additional proangiogenic targets that have emerged as potential mediators of ocular neovascularization include hypoxia-inducible factor-1, angiopoietin-2, platelet-derived growth factor-B and components of the alternative complement pathway. As for VEGF, knowledge of these factors has led to a product pipeline of many more novel agents that are in various stages of clinical development in the setting of ocular neovascularization. These agents are represented by a range of drug classes and, in addition to novel small- and large-molecule VEGF inhibitors, include gene therapies, small interfering RNA agents and tyrosine kinase inhibitors. In addition, combination therapy is beginning to emerge as a strategy to improve the efficacy of individual therapies. Thus, a variety of agents, whether administered alone or as adjunctive therapy with agents targeting VEGF, offer the promise of expanding the range of treatments for ocular neovascular diseases. © 2016 S. Karger AG, Basel.

Growth of Wide Band Gap II-VI Compound Semiconductors by Physical Vapor Transport

NASA Technical Reports Server (NTRS)

Su, Ching-Hua; Sha, Yi-Gao

1995-01-01

The studies on the crystal growth and characterization of II-VI wide band gap compound semiconductors, such as ZnTe, CdS, ZnSe and ZnS, have been conducted over the past three decades. The research was not quite as extensive as that on Si, III-V, or even narrow band gap II-VI semiconductors because of the high melting temperatures as well as the specialized applications associated with these wide band gap semiconductors. In the past several years, major advances in the thin film technology such as Molecular Beam Epitaxy (MBE) and Metal Organic Chemical Vapor Deposition (MOCVD) have demonstrated the applications of these materials for the important devices such as light-emitting diode, laser and ultraviolet detectors and the tunability of energy band gap by employing ternary or even quaternary systems of these compounds. At the same time, the development in the crystal growth of bulk materials has not advanced far enough to provide low price, high quality substrates needed for the thin film growth technology.

The role of small molecule platelet-derived growth factor receptor (PDGFR) inhibitors in the treatment of neoplastic disorders.

PubMed

Roskoski, Robert

2018-03-01

Platelet-derived growth factor (PDGF) was discovered as a serum-derived component necessary for the growth of smooth muscle cells, fibroblasts, and glial cells. The PDGF family is a product of four gene products and consists of five dimeric isoforms: PDGF-AA, PDGF-BB, PDGF-CC, PDGF-DD, and the PDGF-AB heterodimer. This growth factor family plays an essential role in embryonic development and in wound healing in the adult. These growth factors mediate their effects by binding to and activating their receptor protein-tyrosine kinases, which are encoded by two genes: PDGFRA and PDGFRB. The functional receptors consist of the PDGFRα/α and PDGFRβ/β homodimers and the PDGFRα/β heterodimer. Although PDGF signaling is most closely associated with mesenchymal cells, PDGFs and PDGF receptors are widely expressed in the mammalian central nervous system. The PDGF receptors contain an extracellular domain that is made up of five immunoglobulin-like domains (Ig-d1/2/3/4/5), a transmembrane segment, a juxtamembrane segment, a protein-tyrosine kinase domain that contains an insert of about 100 amino acid residues, and a carboxyterminal tail. Although uncommon, activating mutations in the genes for PDGF or PDGF receptors have been documented in various neoplasms including dermatofibrosarcoma protuberans (DFSP) and gastrointestinal stromal tumors (GIST). In most neoplastic diseases, PDGF expression and action appear to involve the tumor stroma. Moreover, this family is pro-angiogenic. More than ten PDGFRα/β multikinase antagonists have been approved by the FDA for the treatment of several neoplastic disorders and interstitial pulmonary fibrosis (www.brimr.org/PKI/PKIs.htm). Type I protein kinase inhibitors interact with the active enzyme form with DFG-D of the proximal activation segment directed inward toward the active site (DFG-D in ). In contrast, type II inhibitors bind to their target with the DFG-D pointing away from the active site (DFG-D out ). We used the Schr

The Curiosity and Exploration Inventory-II: Development, Factor Structure, and Psychometrics

PubMed Central

Kashdan, Todd B.; Gallagher, Matthew W.; Silvia, Paul J.; Winterstein, Beate P.; Breen, William E.; Terhar, Daniel; Steger, Michael F.

2009-01-01

Given curiosity’s fundamental role in motivation, learning, and well-being, we sought to refine the measurement of trait curiosity with an improved version of the Curiosity and Exploration Inventory (CEI; Kashdan, Rose, & Fincham, 2004). A preliminary pool of 36 items was administered to 311 undergraduate students, who also completed measures of emotion, emotion regulation, personality, and well-being. Factor analyses indicated a two factor model—motivation to seek out knowledge and new experiences (Stretching; 5 items) and a willingness to embrace the novel, uncertain, and unpredictable nature of everyday life (Embracing; 5 items). In two additional samples (ns = 150 and 119), we cross-validated this factor structure and provided initial evidence for construct validity. This includes positive correlations with personal growth, openness to experience, autonomy, purpose in life, self-acceptance, psychological flexibility, positive affect, and positive social relations, among others. Applying item response theory (IRT) to these samples (n = 578), we showed that the items have good discrimination and a desirable breadth of difficulty. The item information functions and test information function were centered near zero, indicating that the scale assesses the mid-range of the latent curiosity trait most reliably. The findings thus far provide good evidence for the psychometric properties of the 10-item CEI-II. PMID:20160913

Dietary protein during gestation affects maternal insulin-like growth factor, insulin-like growth factor binding protein, leptin concentrations, and fetal growth in heifers.

PubMed

Sullivan, T M; Micke, G C; Perkins, N; Martin, G B; Wallace, C R; Gatford, K L; Owens, J A; Perry, V E A

2009-10-01

The influence of supplemental protein during gestation on maternal hormones and fetal growth was determined in composite beef heifers. At AI, 118 heifers were stratified by BW within each composite genotype (BeefX = 1/2 Senepol, 1/4 Brahman, 1/8 Charolais, 1/8 Red Angus and CBX = 1/2 Senepol, 1/4 Brahman, 1/4 Charolais) into 4 treatment groups: high high (HH = 1.4 kg CP/d for first and second trimesters of gestation), high low (HL = 1.4 kg of CP/d for first trimester and 0.4 kg of CP/d for second trimester), low high (lowH = 0.4 kg CP/d for first trimester and 1.4 kg of CP/d and for second trimester), or low low (LL = 0.4 kg CP/d for first and second trimesters). Maternal plasma IGF-I and -II, total IGFBP, and leptin concentrations were determined at 14 d before AI and at d 28, 82, 179, and 271 post-AI (mean gestation length 286 d), and leptin concentrations were also determined at calving. Increased dietary protein increased maternal plasma IGF-I (P < 0.001 on d 28, 82, and 179), IGF-II (P = 0.01 on d 82; P = 0.04 on d 271), and total IGFBP (P = 0.002 on d 82; P = 0.005 on d 179; P = 0.03 on d 271). Maternal plasma IGF-I at d 271 was negatively associated with calf crown-rump length at birth (P = 0.003). BeefX had greater birth weight calves (P = 0.01), greater IGF-II (P < 0.001), increased ratios of IGF-I:total IGFBP (P = 0.008) and IGF-II:total IGFBP (P < 0.001), and reduced total IGFBP compared with CBX (P = 0.02). Increased dietary protein during second trimester increased maternal plasma leptin at calving (P = 0.005). Maternal plasma leptin near term was positively associated with heifer BCS (P = 0.02) and with calf birth weight (P = 0.04), and at calving was positively associated with heifer age at AI (P = 0.02). These findings suggest that maternal dietary protein, age, and genotype influence plasma concentrations of metabolic hormones and fetal growth in Bos indicus-influenced heifers.

Bone-Derived Growth Factors

PubMed Central

Capanna, R.; Campanacci, D.A.; De Biase, P.; Cuomo, P.; Lorenzoni, A.

2010-01-01

Bone regeneration is based on the synergy between osteconduction, osteoinduction and osteogenesis. In recent years, we have witnessed the birth and development of numerous osteoconductive substrates, created with the intention of replacing bone grafts, both autologous and homologous. Recently, attention has shifted to osteogenesis, in other words, to the study of mesenchymal cells and their differentiation into osteoblastic cell lines that can be cultured in vitro (as already seen with chondroblasts). Osteoinduction, too, has been shown to be equally important, ever since Urist’s 1967 study which drew attention to the demineralised bone matrix and its properties. The following twenty years led to the definition of bone morphogenetic protein (BMP) and finally to the marketing of the first ostegenic protein (OP-1) obtained by means of the gene recombination technique. The BMPs produced using this technique that, so far, have been shown to be most active are BMP-2 (Infuse) and BMP-7 (Osigraft). The BMPs are not the only molecules with osteoinductive capacity. Other molecules capable of influencing bone regeneration are: platelet-derived growth factors (PDGFs), the transforming growth factor-beta (TGF-β) family, insulin-like growth factor (IGF-I) and the acidic and basic fibroblast growth factors (FGFs). All these growth factors act in synergy with the BMPs, modulating their action and exerting an inductive and proliferative action on the cell lines responsible for regenerating the bone matrix. The literature has been literally invaded by studies, both experimental and preclinical, on these proteins (Termaat, 2005), and they have provided ample demonstration that the BMPs are effective in improving healing of fractures, pseudoarthrosis and spinal fusions. Important advantages of BMPs are the complete absence of risk of transmissible disease, given that they are produced using recombination technology; their purity, and thus absence of an immune response (although

A Histologically Distinctive Interstitial Pneumonia Induced by Overexpression of the Interleukin 6, Transforming Growth Factor β1, or Platelet-Derived Growth Factor B Gene

NASA Astrophysics Data System (ADS)

Yoshida, Mitsuhiro; Sakuma, Junko; Hayashi, Seiji; Abe, Kin'ya; Saito, Izumu; Harada, Shizuko; Sakatani, Mitsunoir; Yamamoto, Satoru; Matsumoto, Norinao; Kaneda, Yasufumi; Kishmoto, Tadamitsu

1995-10-01

Interstitial pneumonia is characterized by alveolitis with resulting fibrosis of the interstitium. To determine the relevance of humoral factors in the pathogenesis of interstitial pneumonia, we introduced expression vectors into Wistar rats via the trachea to locally overexpress humoral factors in the lungs. Human interleukin (IL) 6 and IL-6 receptor genes induced lymphocytic alveolitis without marked fibroblast proliferation. In contrast, overexpression of human transforming growth factor β1 or human platelet-derived growth factor B gene induced only mild or apparent cellular infiltration in the alveoli, respectively. However, both factors induced significant proliferation of fibroblasts and deposition of collagen fibrils. These histopathologic changes induced by the transforming growth factor β1 and platelet-derived growth factor B gene are partly akin to those changes seen in lung tissues from patients with pulmonary fibrosis and markedly contrast with the changes induced by overexpression of the IL-6 and IL-6 receptor genes that mimics lymphocytic interstitial pneumonia.

Potential role of fibroblast growth factor in enhancement of fracture healing.

PubMed

Radomsky, M L; Thompson, A Y; Spiro, R C; Poser, J W

1998-10-01

Fibroblast growth factors are present in significant amounts in bone and several studies have suggested that they may be involved in normal fracture healing. It is well established that fibroblast growth factors have mitogenic and angiogenic activity on mesoderm and neuroectoderm derived cells. Of particular interest as a member of the fibroblast growth factor family, basic fibroblast growth factor stimulates mitogenesis, chemotaxis, differentiation, and angiogenesis. It also plays an important role in the development of vascular, nervous, and skeletal systems, promotes the maintenance and survival of certain tissues, and stimulates wound healing and tissue repair. Animal studies have shown that the direct injection of fibroblast growth factor into fresh fractures stimulates callus formation, which provides mechanical stability to the fracture, accelerates healing, and restores competence. The matrix used to present the fibroblast growth factor at the fracture site plays a critical role in the effectiveness of the treatment. The evaluation of injectable basic fibroblast growth factor in a sodium hyaluronate gel for its effectiveness in stimulating fracture healing is described. When applied directly into a freshly created fracture in the rabbit fibula, a single injection of the basic fibroblast growth factor and hyaluronan results in the stimulation of callus formation, increased bone formation, and earlier restoration of mechanical strength at the fracture site. The hyaluronan gel serves as a reservoir that sequesters the basic fibroblast growth factor at the injection site for the length of time necessary to create an environment conducive to fracture healing. It is concluded that basic fibroblast growth factor and sodium hyaluronate act synergistically to accelerate fracture healing and that the combination is suitable for clinical evaluation as a therapy in fracture treatment.

Insulin-like signaling (IIS) responses to temperature, genetic background, and growth variation in garter snakes with divergent life histories.

PubMed

Reding, Dawn M; Addis, Elizabeth A; Palacios, Maria G; Schwartz, Tonia S; Bronikowski, Anne M

2016-07-01

The insulin/insulin-like signaling pathway (IIS) has been shown to mediate life history trade-offs in mammalian model organisms, but the function of this pathway in wild and non-mammalian organisms is understudied. Populations of western terrestrial garter snakes (Thamnophis elegans) around Eagle Lake, California, have evolved variation in growth and maturation rates, mortality senescence rates, and annual reproductive output that partition into two ecotypes: "fast-living" and "slow-living". Thus, genes associated with the IIS network are good candidates for investigating the mechanisms underlying ecological divergence in this system. We reared neonates from each ecotype for 1.5years under two thermal treatments. We then used qPCR to compare mRNA expression levels in three tissue types (brain, liver, skeletal muscle) for four genes (igf1, igf2, igf1r, igf2r), and we used radioimmunoassay to measure plasma IGF-1 and IGF-2 protein levels. Our results show that, in contrast to most mammalian model systems, igf2 mRNA and protein levels exceed those of igf1 and suggest an important role for igf2 in postnatal growth in reptiles. Thermal rearing treatment and recent growth had greater impacts on IGF levels than genetic background (i.e., ecotype), and the two ecotypes responded similarly. This suggests that observed ecotypic differences in field measures of IGFs may more strongly reflect plastic responses in different environments than evolutionary divergence. Future analyses of additional components of the IIS pathway and sequence divergence between the ecotypes will further illuminate how environmental and genetic factors influence the endocrine system and its role in mediating life history trade-offs. Copyright © 2016 Elsevier Inc. All rights reserved.

Neural Stem Cell Differentiation Using Microfluidic Device-Generated Growth Factor Gradient.

PubMed

Kim, Ji Hyeon; Sim, Jiyeon; Kim, Hyun-Jung

2018-04-11

Neural stem cells (NSCs) have the ability to self-renew and differentiate into multiple nervous system cell types. During embryonic development, the concentrations of soluble biological molecules have a critical role in controlling cell proliferation, migration, differentiation and apoptosis. In an effort to find optimal culture conditions for the generation of desired cell types in vitro , we used a microfluidic chip-generated growth factor gradient system. In the current study, NSCs in the microfluidic device remained healthy during the entire period of cell culture, and proliferated and differentiated in response to the concentration gradient of growth factors (epithermal growth factor and basic fibroblast growth factor). We also showed that overexpression of ASCL1 in NSCs increased neuronal differentiation depending on the concentration gradient of growth factors generated in the microfluidic gradient chip. The microfluidic system allowed us to study concentration-dependent effects of growth factors within a single device, while a traditional system requires multiple independent cultures using fixed growth factor concentrations. Our study suggests that the microfluidic gradient-generating chip is a powerful tool for determining the optimal culture conditions.

Growth factors and myometrium: biological effects in uterine fibroid and possible clinical implications

PubMed Central

Ciarmela, Pasquapina; Islam, Md. Soriful; Reis, Fernando M.; Gray, Peter C.; Bloise, Enrrico; Petraglia, Felice; Vale, Wylie; Castellucci, Mario

2011-01-01

BACKGROUND Growth factors are proteins secreted by a number of cell types that are capable of modulating cellular growth, proliferation and cellular differentiation. It is well accepted that uterine cellular events such as proliferation and differentiation are regulated by sex steroids and their actions in target tissues are mediated by local production of growth factors acting through paracrine and/or autocrine mechanisms. Myometrial mass is ultimately modified in pregnancy as well as in tumour conditions such as leiomyoma and leiomyosarcoma. Leiomyomas, also known as fibroids, are benign tumours of the uterus, considered to be one of the most frequent causes of infertility in reproductive years in women. METHODS For this review, we searched the database MEDLINE and Google Scholar for articles with content related to growth factors acting on myometrium; the findings are hereby reviewed and discussed. RESULTS Different growth factors such as epidermal growth factor (EGF), transforming growth factor-α (TGF-α), heparin-binding EGF (HB-EGF), acidic fibroblast growth factor (aFGF), basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), insulin-like growth factor (IGF), platelet-derived growth factor (PDGF) and TGF-β perform actions in myometrium and in leiomyomas. In addition to these growth factors, activin and myostatin have been recently identified in myometrium and leiomyoma. CONCLUSIONS Growth factors play an important role in the mechanisms involved in myometrial patho-physiology. PMID:21788281

The Effect of Desulfation of Chondroitin Sulfate on Interactions with Positively Charged Growth Factors and Upregulation of Cartilaginous Markers in Encapsulated MSCs

PubMed Central

Lim, Jeremy J.; Temenoff, Johnna S.

2013-01-01

Sulfated glycosaminoglycans (GAGs) are known to interact electrostatically with positively charged growth factors to modulate signaling. Therefore, regulating the degree of sulfation of GAGs may be a promising approach to tailor biomaterial carriers for controlled growth factor delivery and release. For this study, chondroitin sulfate (CS) was first desulfated to form chondroitin, and resulting crosslinked CS and chondroitin hydrogels were examined in vitro for release of positively charged model protein (histone) and for their effect on cartilaginous differentiation of encapsulated human mesenchymal stem cells (MSCs). Desulfation significantly increased the release of histone from chondroitin hydrogels (30.6±2.3 ìg released over 8 days, compared to natively sulfated CS with 20.2±0.8 ìg), suggesting that sulfation alone plays a significant role in modulating protein interactions with GAG hydrogels. MSCs in chondroitin hydrogels significantly upregulated gene expression of collagen II and aggrecan by day 21 in chondrogenic medium (115±100 and 23.1±7.9 fold upregulation of collagen II and aggrecan, respectively), compared to CS and PEG-based swelling controls, indicating that desulfation may actually enhance the response of MSCs to soluble chondrogenic cues, such as TGF-â1. Thus, desulfated chondroitin materials present a promising biomaterial tool to further investigate electrostatic GAG/growth factor interactions, especially for repair of cartilaginous tissues. PMID:23570717

The effect of desulfation of chondroitin sulfate on interactions with positively charged growth factors and upregulation of cartilaginous markers in encapsulated MSCs.

PubMed

Lim, Jeremy J; Temenoff, Johnna S

2013-07-01

Sulfated glycosaminoglycans (GAGs) are known to interact electrostatically with positively charged growth factors to modulate signaling. Therefore, regulating the degree of sulfation of GAGs may be a promising approach to tailor biomaterial carriers for controlled growth factor delivery and release. For this study, chondroitin sulfate (CS) was first desulfated to form chondroitin, and resulting crosslinked CS and chondroitin hydrogels were examined in vitro for release of positively charged model protein (histone) and for their effect on cartilaginous differentiation of encapsulated human mesenchymal stem cells (MSCs). Desulfation significantly increased the release of histone from chondroitin hydrogels (30.6 ± 2.3 μg released over 8 days, compared to natively sulfated CS with 20.2 ± 0.8 μg), suggesting that sulfation alone plays a significant role in modulating protein interactions with GAG hydrogels. MSCs in chondroitin hydrogels significantly upregulated gene expression of collagen II and aggrecan by day 21 in chondrogenic medium (115 ± 100 and 23.1 ± 7.9 fold upregulation of collagen II and aggrecan, respectively), compared to CS hydrogels and PEG-based swelling controls, indicating that desulfation may actually enhance the response of MSCs to soluble chondrogenic cues, such as TGF-β1. Thus, desulfated chondroitin materials present a promising biomaterial tool to further investigate electrostatic GAG/growth factor interactions, especially for repair of cartilaginous tissues. Copyright © 2013 Elsevier Ltd. All rights reserved.

Increased expression of placental growth factor in high-grade endometrial carcinoma.

PubMed

Coenegrachts, Lieve; Schrauwen, Stefanie; Van Bree, Rita; Despierre, Evelyn; Luyten, Catherine; Jonckx, Bart; Stassen, Jean Marie; Vergote, Ignace; Amant, Frédéric

2013-02-01

Placental growth factor (PlGF), a homolog of vascular endothelial growth factor (VEGF), exerts pleiotropic functions in cancer by affecting tumor cells as well as endothelial and inflammatory cells. Moreover, PlGF expression correlates with tumor stage, recurrence, metastasis and patient outcome in different types of cancer. Recently, administration of anti-PlGF therapy reduced tumor growth and metastasis in preclinical tumor models. In the present study, we evaluated the diagnostic and prognostic value of systemic and local expression of PlGF in primary endometrial carcinomas. PlGF levels in tumor lysates (n=128) and serum (n=88) of patients with primary endometrial cancer were determined using ELISA. PlGF mRNA expression in endometrial carcinoma tissues was quantified by quantitative qRT-PCR. Results were compared to endometrial cancer stage and grade. Systemic PlGF levels were not altered in patients with endometrial cancer (FIGO stage I-II-III) as compared to healthy controls. Only in FIGO stage IV patients, serum PlGF levels were slightly increased. Local PlGF mRNA and protein expression in endometrial tumors progressively increased with tumor grade. In endometrioid carcinomas, PlGF mRNA expression was significantly increased in endometrioid grade 3 tumors as compared to normal endometrial tissue. PlGF protein expression was significantly increased in endometrioid grade 2 and 3 carcinomas and in serous carcinomas as compared to normal endometrial tissue. Our study showed that systemic/serum PlGF levels cannot be used as a diagnostic or prognostic marker in endometrial cancer. However, the increased local expression of PlGF, primarily in high-grade carcinomas, underscores the possibility for preclinical assessment of anti-PlGF therapy in endometrial cancer.

Chitosan conduits combined with nerve growth factor microspheres repair facial nerve defects

PubMed Central

Liu, Huawei; Wen, Weisheng; Hu, Min; Bi, Wenting; Chen, Lijie; Liu, Sanxia; Chen, Peng; Tan, Xinying

2013-01-01

Microspheres containing nerve growth factor for sustained release were prepared by a compound method, and implanted into chitosan conduits to repair 10-mm defects on the right buccal branches of the facial nerve in rabbits. In addition, chitosan conduits combined with nerve growth factor or normal saline, as well as autologous nerve, were used as controls. At 90 days post-surgery, the muscular atrophy on the right upper lip was more evident in the nerve growth factor and normal sa-line groups than in the nerve growth factor-microspheres and autologous nerve groups. physiological analysis revealed that the nerve conduction velocity and amplitude were significantly higher in the nerve growth factor-microspheres and autologous nerve groups than in the nerve growth factor and normal saline groups. Moreover, histological observation illustrated that the di-ameter, number, alignment and myelin sheath thickness of myelinated nerves derived from rabbits were higher in the nerve growth factor-microspheres and autologous nerve groups than in the nerve growth factor and normal saline groups. These findings indicate that chitosan nerve conduits bined with microspheres for sustained release of nerve growth factor can significantly improve facial nerve defect repair in rabbits. PMID:25206635

Fibroblast Growth Factor 2: An Epithelial Ductal Cell Growth Inhibitor That Drops Out in Breast Cancer

DTIC Science & Technology

2010-10-01

AD_________________ Award Number: W81XWH-08-1-0708 TITLE: Fibroblast Growth Factor 2: an...September 2009 – 14 September 2010 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Fibroblast Growth Factor 2: an Epithelial Ductal Cell Growth ...8 Appendices…………………………………………………………………………… 8 Supporting Data……………………………………………………………………... 8 Fibroblast Growth Factor -2: an

Suppression of glioblastoma angiogenicity and tumorigenicity by inhibition of endogenous expression of vascular endothelial growth factor.

PubMed Central

Cheng, S Y; Huang, H J; Nagane, M; Ji, X D; Wang, D; Shih, C C; Arap, W; Huang, C M; Cavenee, W K

1996-01-01

The development of new capillary networks from the normal microvasculature of the host appears to be required for growth of solid tumors. Tumor cells influence this process by producing both inhibitors and positive effectors of angiogenesis. Among the latter, the vascular endothelial growth factor (VEGF) has assumed prime candidacy as a major positive physiological effector. Here, we have directly tested this hypothesis in the brain tumor, glioblastoma multiforme, one of the most highly vascularized human cancers. We introduced an antisense VEGF expression construct into glioblastoma cells and found that (i) VEGF mRNA and protein levels were markedly reduced, (ii) the modified cells did not secrete sufficient factors so as to be chemoattractive for primary human microvascular endothelial cells, (iii) the modified cells were not able to sustain tumor growth in immunodeficient animals, and (iv) the density of in vivo blood vessel formation was reduced in direct relation to the reduction of VEGF secretion and tumor formation. Moreover, revertant cells that recovered the ability to secrete VEGF regained each of these tumorigenic properties. These results suggest that VEGF plays a major angiogenic role in glioblastoma. Images Fig. 1 Fig. 4 PMID:8710899

Crosstalk between insulin-like growth factor-1 and angiotensin-II in dopaminergic neurons and glial cells: role in neuroinflammation and aging.

PubMed

Rodriguez-Perez, Ana I; Borrajo, Ana; Diaz-Ruiz, Carmen; Garrido-Gil, Pablo; Labandeira-Garcia, Jose L

2016-05-24

The local renin-angiotensin system (RAS) and insulin-like growth factor 1 (IGF-1) have been involved in longevity, neurodegeneration and aging-related dopaminergic degeneration. However, it is not known whether IGF-1 and angiotensin-II (AII) activate each other. In the present study, AII, via type 1 (AT1) receptors, exacerbated neuroinflammation and dopaminergic cell death. AII, via AT1 receptors, also increased the levels of IGF-1 and IGF-1 receptors in microglial cells. IGF-1 inhibited RAS activity in dopaminergic neurons and glial cells, and also inhibited the AII-induced increase in markers of the M1 microglial phenotype. Consistent with this, IGF-1 decreased dopaminergic neuron death induced by the neurotoxin MPP+ both in the presence and in the absence of glia. Intraventricular administration of AII to young rats induced a significant increase in IGF-1 expression in the nigral region. However, aged rats showed decreased levels of IGF-1 relative to young controls, even though RAS activity is known to be enhanced in aged animals. The study findings show that IGF-1 and the local RAS interact to inhibit or activate neuroinflammation (i.e. transition from the M1 to the M2 phenotype), oxidative stress and dopaminergic degeneration. The findings also show that this mechanism is impaired in aged animals.

Crosstalk between insulin-like growth factor-1 and angiotensin-II in dopaminergic neurons and glial cells: role in neuroinflammation and aging

PubMed Central

Rodriguez-Perez, Ana I.; Borrajo, Ana; Diaz-Ruiz, Carmen; Garrido-Gil, Pablo; Labandeira-Garcia, Jose L.

2016-01-01

The local renin-angiotensin system (RAS) and insulin-like growth factor 1 (IGF-1) have been involved in longevity, neurodegeneration and aging-related dopaminergic degeneration. However, it is not known whether IGF-1 and angiotensin-II (AII) activate each other. In the present study, AII, via type 1 (AT1) receptors, exacerbated neuroinflammation and dopaminergic cell death. AII, via AT1 receptors, also increased the levels of IGF-1 and IGF-1 receptors in microglial cells. IGF-1 inhibited RAS activity in dopaminergic neurons and glial cells, and also inhibited the AII-induced increase in markers of the M1 microglial phenotype. Consistent with this, IGF-1 decreased dopaminergic neuron death induced by the neurotoxin MPP+ both in the presence and in the absence of glia. Intraventricular administration of AII to young rats induced a significant increase in IGF-1 expression in the nigral region. However, aged rats showed decreased levels of IGF-1 relative to young controls, even though RAS activity is known to be enhanced in aged animals. The study findings show that IGF-1 and the local RAS interact to inhibit or activate neuroinflammation (i.e. transition from the M1 to the M2 phenotype), oxidative stress and dopaminergic degeneration. The findings also show that this mechanism is impaired in aged animals. PMID:27167199

Production of insulin-like growth factor binding proteins by small-cell lung cancer cell lines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jaques, G.; Kiefer, P.; Rotsch, M.

1989-10-01

Conditioned serum-free media (CM) from small-cell lung cancer (SCLC) cell lines were examined for the presence of insulin-like growth-factor-binding proteins (IGF-BP). 6/9 SCLC cell lines secreted binding proteins with high affinity for IGFs. When ({sup 125}I)IGF-1 or ({sup 125}I)IGF-II was incubated with the CMs, complexes of tracer with proteins could be demonstrated by gel filtration, by precipitation with polyethylenglycol, and after adsorption of unbound tracer with activated charcoal. Analysis of binding data according to the method of Scatchard resulted in linear plots for IGF-I and IGF-II. Cross-linking of ({sup 125}I)IGF-I or ({sup 125}I)IGF-II to the CMs followed by sodium dodecylmore » sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) under nonreducing conditions revealed the presence of IGF-BPs with molecular masses in the range of 24-32 kDa. Northern blot hybridization with an IGF-BP cDNA probe encoding a low-molecular-weight IGF-BP from a human placenta cDNA library and Western blot analysis with a corresponding polyclonal antibody showed no expression of this gene. These data demonstrate that SCLC cell lines release IGF-BPs in culture supernatants, which differ from IGF-BPs detected in liver and placenta. These IGF-BPs might be important mediators in the autocrine/paracrine growth regulation of IGFs in SCLC.« less

Platelet-derived growth factor inhibits platelet activation in heparinized whole blood.

PubMed

Selheim, F; Holmsen, H; Vassbotn, F S

1999-08-15

We previously have demonstrated that human platelets have functionally active platelet-derived growth factor alpha-receptors. Studies with gel-filtered platelets showed that an autocrine inhibition pathway is transduced through this tyrosine kinase receptor during platelet activation. The physiological significance of this inhibitory effect of platelet-derived growth factor on gel-filtered platelets activation is, however, not known. In the present study, we investigated whether platelet-derived growth factor inhibits platelet activation under more physiological conditions in heparinized whole blood, which represents a more physiological condition than gel-filtered platelets. Using flow cytometric assays, we demonstrate here that platelet-derived growth factor inhibits thrombin-, thrombin receptor agonist peptide SFLLRN-, and collagen-induced platelet aggregation and shedding of platelet-derived microparticles from the platelet plasma membrane during platelet aggregation in stirred heparinized whole blood. The inhibitory effect of platelet-derived growth factor was dose dependent. However, under nonaggregating conditions (no stirring), we could not demonstrate any significant effect of platelet-derived growth factor on thrombin- and thrombin receptor agonist peptide-induced platelet surface expression of P-selectin. Our results demonstrate that platelet-derived growth factor appears to be a true antithrombotic agent only under aggregating conditions in heparinized whole blood.

Gelatin Methacrylate Microspheres for Growth Factor Controlled Release

PubMed Central

Nguyen, Anh H.; McKinney, Jay; Miller, Tobias; Bongiorno, Tom; McDevitt, Todd C.

2014-01-01

Gelatin has been commonly used as a delivery vehicle for various biomolecules for tissue engineering and regenerative medicine applications due to its simple fabrication methods, inherent electrostatic binding properties, and proteolytic degradability. Compared to traditional chemical cross-linking methods, such as the use of glutaraldehyde (GA), methacrylate modification of gelatin offers an alternative method to better control the extent of hydrogel cross-linking. Here we examined the physical properties and growth factor delivery of gelatin methacrylate (GMA) microparticles formulated with a wide range of different cross-linking densities (15–90%). Less methacrylated MPs had decreased elastic moduli and larger mesh sizes compared to GA MPs, with increasing methacrylation correlating to greater moduli and smaller mesh sizes. As expected, an inverse correlation between microparticle cross-linking density and degradation was observed, with the lowest cross-linked GMA MPs degrading at the fastest rate, comparable to GA MPs. Interestingly, GMA MPs at lower cross-linking densities could be loaded with up to a 10-fold higher relative amount of growth factor over conventional GA cross-linked MPs, despite an order of magnitude greater gelatin content of GA MPs. Moreover, a reduced GMA cross-linking density resulted in more complete release of bone morphogenic protein 4 (BMP4) and basic fibroblast growth factor (bFGF) and accelerated release rate with collagenase treatment. These studies demonstrate that GMA MPs provide a more flexible platform for growth factor delivery by enhancing the relative binding capacity and permitting proteolytic degradation tunability, thereby offering a more potent controlled release system for growth factor delivery. PMID:25463489

Quinones are growth factors for the human gut microbiota.

PubMed

Fenn, Kathrin; Strandwitz, Philip; Stewart, Eric J; Dimise, Eric; Rubin, Sarah; Gurubacharya, Shreya; Clardy, Jon; Lewis, Kim

2017-12-20

The human gut microbiome has been linked to numerous components of health and disease. However, approximately 25% of the bacterial species in the gut remain uncultured, which limits our ability to properly understand, and exploit, the human microbiome. Previously, we found that growing environmental bacteria in situ in a diffusion chamber enables growth of uncultured species, suggesting the existence of growth factors in the natural environment not found in traditional cultivation media. One source of growth factors proved to be neighboring bacteria, and by using co-culture, we isolated previously uncultured organisms from the marine environment and identified siderophores as a major class of bacterial growth factors. Here, we employ similar co-culture techniques to grow bacteria from the human gut microbiome and identify novel growth factors. By testing dependence of slow-growing colonies on faster-growing neighboring bacteria in a co-culture assay, eight taxonomically diverse pairs of bacteria were identified, in which an "induced" isolate formed a gradient of growth around a cultivatable "helper." This set included two novel species Faecalibacterium sp. KLE1255-belonging to the anti-inflammatory Faecalibacterium genus-and Sutterella sp. KLE1607. While multiple helper strains were identified, Escherichia coli was also capable of promoting growth of all induced isolates. Screening a knockout library of E. coli showed that a menaquinone biosynthesis pathway was required for growth induction of Faecalibacterium sp. KLE1255 and other induced isolates. Purified menaquinones induced growth of 7/8 of the isolated strains, quinone specificity profiles for individual bacteria were identified, and genome analysis suggests an incomplete menaquinone biosynthetic capability yet the presence of anaerobic terminal reductases in the induced strains, indicating an ability to respire anaerobically. Our data show that menaquinones are a major class of growth factors for bacteria

Growth factor-functionalized silk membranes support wound healing in vitro.

PubMed

Bienert, M; Hoss, M; Bartneck, M; Weinandy, S; Böbel, M; Jockenhövel, S; Knüchel, R; Pottbacker, K; Wöltje, M; Jahnen-Dechent, W; Neuss, S

2017-08-16

Chronic wounds represent a serious problem in daily medical routine requiring improved wound care. Silk of the domesticated silkworm (Bombyx mori) has been used to form a variety of biomaterials for medical applications. We genetically engineered B. mori to produce silk functionalized with growth factors to promote wound healing in vitro. In this study FGF-, EGF-, KGF-, PDGF- or VEGF-functionalized silk membranes were compared to native B. mori silk membranes without growth factors for their ability to support wound healing in vitro. All silk membranes were cytocompatible and supported macrophage secretion of neutrophil recruiting factor CXCL1 and monocyte chemoattractant protein 1 (MCP-1). VEGF-functionalized silk significantly outperformed other growth factor-functionalized silk membranes, but not native silk in angiogenesis assays. In addition, EGF- and VEGF-functionalized silk membranes slightly enhanced macrophage adhesion compared to silk without growth factors. In wound healing assays in vitro (reduction of wound lesion), dermal equivalents showed a higher wound healing capacity when covered with EGF-, FGF- or VEGF-functionalized silk membranes compared to native, KGF- or PDGF-functionalized silk membranes. Keratinocyte migration and growth is overstimulated by KGF- and VEGF-functionalized silk membranes. In conclusion, growth factor-functionalized silk membranes prepared from genetically engineered silk worm glands are promising wound dressings for future wound healing therapies.

Therapeutic modulation of growth factors and cytokines in regenerative medicine.

PubMed

Ioannidou, Effie

2006-01-01

Regeneration that takes place in the human body is limited throughout life. Therefore, when organs are irreparably damaged, they are usually replaced with an artificial device or donor organ. The term "regenerative medicine" covers the restoration or replacement of cells, tissues, and organs. Stem cells play a major role in regenerative medicine by providing the way to repopulate organs damaged by disease. Stem cells have the ability to self renew and to regenerate cells of diverse lineages within the tissue in which they reside. Stem cells could originate from embryos or adult tissues. Growth factors are proteins that may act locally or systemically to affect the growth of cells in several ways. Various cell activities, including division, are influenced by growth factors. Cytokines are a family of low-molecular-weight proteins that are produced by numerous cell types and are responsible for regulating the immune response, inflammation, tissue remodeling and cellular differentiation. Target cells of growth factors and cytokines are mesenchymal, epithelial and endothelial cells. These molecules frequently have overlapping activities and can act in an autocrine or paracrine fashion. A complex network of growth factors and cytokines guides cellular differentiation and regeneration in all organs and tissues. The aim of this paper is to review the role of growth factors and cytokines in different organs or systems and explore their therapeutic application in regenerative medicine. The role of stem cells combined with growth factors and cytokines in the regeneration of vascular and hematopoietic, neural, skeletal, pancreatic, periodontal, and mucosal tissue is reviewed. There is evidence that supports the use of growth factors and cytokines in the treatment of neurological diseases, diabetes, cardiovascular disease, periodontal disease, cancer and its complication, oral mucositis. After solving the ethical issues and establishing clear and reasonable regulations

Role of Insulinlike Growth Factor 1 in Fetal Development and in the Early Postnatal Life of Premature Infants

PubMed Central

Hellström, Ann; Ley, David; Hansen-Pupp, Ingrid; Hallberg, Boubou; Ramenghi, Luca A.; Löfqvist, Chatarina; Smith, Lois E. H.; Hård, Anna-Lena

2018-01-01

The neonatal period of very preterm infants is often characterized by a difficult adjustment to extrauterine life, with an inadequate nutrient supply and insufficient levels of growth factors, resulting in poor growth and a high morbidity rate. Long-term multisystem complications include cognitive, behavioral, and motor dysfunction as a result of brain damage as well as visual and hearing deficits and metabolic disorders that persist into adulthood. Insulinlike growth factor 1 (IGF-1) is a major regulator of fetal growth and development of most organs especially the central nervous system including the retina. Glucose metabolism in the developing brain is controlled by IGF-1 which also stimulates differentiation and prevents apoptosis. Serum concentrations of IGF-1 decrease to very low levels after very preterm birth and remain low for most of the perinatal development. Strong correlations have been found between low neonatal serum concentrations of IGF-1 and poor brain and retinal growth as well as poor general growth with multiorgan morbidities, such as intraventricular hemorrhage, retinopathy of prematurity, bronchopulmonary dysplasia, and necrotizing enterocolitis. Experimental and clinical studies indicate that early supplementation with IGF-1 can improve growth in catabolic states and reduce brain injury after hypoxic/ischemic events. A multicenter phase II study is currently underway to determine whether intravenous replacement of human recombinant IGF-1 up to normal intrauterine serum concentrations can improve growth and development and reduce prematurity-associated morbidities. PMID:27603537

[Effect of cryotherapy over the expression of vascular endothelial growth factor and pigment epithelium-derived factor].

PubMed

Toscano-Garibay, Julia Dolores; Quiroz-Mercado, Hugo; Espitia-Pinzón, Clara; Gil-Carrasco, Félix; Flores-Estrada, José Javier

2014-01-01

Cryotherapy is a no invasive technique that uses intense cold to freeze and destroy cancer tissues. There are no descriptions of its effects over the expression of vascular endothelial growth factor and pigment epithelium-derived factor. Experimental study in cryogenic spot were applied in the right sclera of twelve pigs for ten minutes. Other 3 pigs were used as normal controls. Animals were sacrificed at 7, 14 and 21 and the tissues of choriodes and retina were dissected in areas of approximately 1 cm2 surrounding cryogenic spots. Expression levels of vascular endothelial growth factor and pigment epithelium-derived factor were determined analyzed using polymerase chain reaction coupled to reverse-transcription. Vascular endothelial growth factor was significantly downregulated (24%, p< 0.05) seven days post-treatment meanwhile pigment epithelium-derived factor levels increased 44.8% (p< 0.05) as compared to normal controls (untreated). Both vascular endothelial growth factor and pigment epithelium-derived factor levels remain the same until day 14 but returned to basal expression at day 21. This work expose the relation of cryotherapy with the expression of two factors related to angiogenesis. RESULTS showed significant changes on the expression of vascular endothelial growth factor and pigment epithelium-derived factor illustrating that both proteins are regulated in response to cryogenic treatment in relatively short periods (21 days).

EGFR ligands drive multipotential stromal cells to produce multiple growth factors and cytokines via early growth response-1.

PubMed

Kerpedjieva, Svetoslava S; Kim, Duk Soo; Barbeau, Dominique J; Tamama, Kenichi

2012-09-01

Cell therapy with adult bone marrow multipotential stromal cells/mesenchymal stem cells (MSCs) presents a promising approach to promote wound healing and tissue regeneration. The strong paracrine capability of various growth factors and cytokines is a key mechanism of MSC-mediated wound healing and tissue regeneration, and the goal of this study is to understand the underlying mechanism that supports the strong paracrine machineries in MSCs. Microarray database analyses revealed that early growth response-1 (EGR1) is highly expressed in MSCs. Our previous studies showed that epidermal growth factor (EGF) treatment induces growth factor production in MSCs in vitro. Since EGF strongly upregulates EGR1, we hypothesized that EGF receptor (EGFR)-EGR1 signaling plays a pivotal role in MSC paracrine activity. EGF treatment upregulated the gene expression of growth factors and cytokines, including EGFR ligands in a protein kinase C (PKC)- and/or mitogen-activated protein kinase-extracellular-signal-regulated kinase-dependent manner, and it was reversed by shRNA against EGR1. PKC activator phorbol 12-myristate 13-acetate enhanced EGFR tyrosyl phosphorylation and upregulated the gene expression of growth factors and cytokines in a heparin-binding EGF-like growth factor (HBEGF) inhibitor CRM197 sensitive manner, indicating an involvement of autocrined HBEGF in the downstream of PKC signaling. Moreover, stimulation with growth factors and cytokines induced the expression of EGFR ligands, presumably via EGR1 upregulation. These data indicate EGR1 as a convergence point of multiple signaling pathways, which in turn augments the production of multiple growth factors and cytokines by enhancing the autocrine signaling with EGFR ligands.

Keratinocyte growth factor is a growth factor for mammary epithelium in vivo. The mammary epithelium of lactating rats is resistant to the proliferative action of keratinocyte growth factor.

PubMed Central

Ulich, T. R.; Yi, E. S.; Cardiff, R.; Yin, S.; Bikhazi, N.; Biltz, R.; Morris, C. F.; Pierce, G. F.

1994-01-01

Keratinocyte growth factor (KGF) is a member of the fibroblast growth factor (FGF) family. KGF is secreted by stromal cells and affects epithelial but not mesenchymal cell proliferation. KGF injected intravenously was found to cause dramatic proliferation of mammary epithelium in the mammary glands of rats. KGF causes ductal neogenesis and intraductal epithelial hyperplasia but not lobular differentiation in nulliparous female rats. KGF causes ductal and lobular epithelial hyperplasia in male rats. KGF causes proliferation of ductal and acinar cells in the mammary glands of pregnant rats. On the other hand, the ductal epithelium of lactating postpartum rats is resistant to the proliferative action of KGF. The mammary glands of lactating rats did not express less KGF receptor mRNA than the glands of pregnant rats, suggesting that the resistance of the ductal epithelium to KGF during lactation is not related to KGF receptor mRNA down-regulation. The mammary glands of both pregnant and postpartum lactating rats express KGF mRNA with more KGF present in the glands of lactating rats. In conclusion, the KGF and KGF receptor genes are expressed in rat mammary glands and recombinant KGF is a potent growth factor for mammary epithelium. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:8178937

The glial growth factors deficiency and synaptic destabilization hypothesis of schizophrenia.

PubMed

Moises, Hans W; Zoega, Tomas; Gottesman, Irving I

2002-07-03

A systems approach to understanding the etiology of schizophrenia requires a theory which is able to integrate genetic as well as neurodevelopmental factors. Based on a co-localization of loci approach and a large amount of circumstantial evidence, we here propose that a functional deficiency of glial growth factors and of growth factors produced by glial cells are among the distal causes in the genotype-to-phenotype chain leading to the development of schizophrenia. These factors include neuregulin, insulin-like growth factor I, insulin, epidermal growth factor, neurotrophic growth factors, erbB receptors, phosphatidylinositol-3 kinase, growth arrest specific genes, neuritin, tumor necrosis factor alpha, glutamate, NMDA and cholinergic receptors. A genetically and epigenetically determined low baseline of glial growth factor signaling and synaptic strength is expected to increase the vulnerability for additional reductions (e.g., by viruses such as HHV-6 and JC virus infecting glial cells). This should lead to a weakening of the positive feedback loop between the presynaptic neuron and its targets, and below a certain threshold to synaptic destabilization and schizophrenia. Supported by informed conjectures and empirical facts, the hypothesis makes an attractive case for a large number of further investigations. The hypothesis suggests glial cells as the locus of the genes-environment interactions in schizophrenia, with glial asthenia as an important factor for the genetic liability to the disorder, and an increase of prolactin and/or insulin as possible working mechanisms of traditional and atypical neuroleptic treatments.

Cloning of a cancer cell-producing hepatocyte growth factor, vascular endothelial growth factor, and interleukin-8 from gastric cancer cells.

PubMed

Iwai, Mineko; Matsuda, Masahiko; Iwai, Yoshiaki

2003-01-01

A cell colony (IM95m) that produces hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF), and interleukin-8 (IL-8) was cloned from gastric cancer cells (IM95 cell line). In culture medium, the highest levels of HGF, VEGF, and IL-8 were about 1.1, 0.9, and 0.17 ng/ml culture medium at 3 d from 10(5) cells. IM95m may be useful in elucidating the role of tumor cells in angiogenesis.

Impaired growth in Rabson-Mendenhall syndrome: lack of effect of growth hormone and insulin-like growth factor-I.

PubMed

Longo, N; Singh, R; Griffin, L D; Langley, S D; Parks, J S; Elsas, L J

1994-09-01

Mutations in the insulin receptor gene cause the severe insulin-resistant syndromes leprechaunism and Rabson-Mendenhall syndrome. There is no accepted therapy for these inherited conditions. Here we report the results of recombinant human GH (rhGH) and recombinant human insulin-like growth factor-I (rhIGF-I) treatment of a male patient, Atl-2, with Rabson-Mendenhall syndrome. The patient was small for gestational age, had premature dentition, absence of sc fat, acanthosis nigricans, fasting hypoglycemia and postprandial hyperglycemia, and extremely high concentrations of circulating insulin (up to 8500 microU/mL). Fibroblasts and lymphoblasts established from this patient had reduced insulin binding, which was 20-30% of the control value. Binding of epidermal growth factor, IGF-I, and GH to the patient's fibroblasts was normal. The growth of fibroblasts cultured from patient Atl-2 in vitro was intermediate between that of fibroblasts from patients with leprechaunism and control values. The patient's growth curve in vivo was far below the fifth percentile despite adequate nutrition. To stimulate growth, therapy with rhGH was initiated, the rationale being to stimulate hepatic IGF-I production and IGF-I receptor signaling, and bypass the inherited block in insulin receptor signaling. Therapy with rhGH (up to 0.5 mg/kg.week) did not improve growth and failed to increase the levels of circulating IGF-I and IGF-binding protein-3 over a 14-month period. As rhGH could not stimulate growth, rhIGF-I (up to 100 micrograms/kg.day) was given by daily sc injection. No increase in growth velocity was observed over a 14-month period. These results indicate that both GH and IGF-I fail to correct growth in a patient with severe inherited insulin resistance. The lack of efficacy of IGF-I treatment may be related to multiple factors, such as the poor metabolic state of the patient, the deficiency of serum carrier protein for IGF-I, an increased clearance of the growth factor, IGF

Arctigenin induced gallbladder cancer senescence through modulating epidermal growth factor receptor pathway.

PubMed

Zhang, Mingdi; Cai, Shizhong; Zuo, Bin; Gong, Wei; Tang, Zhaohui; Zhou, Di; Weng, Mingzhe; Qin, Yiyu; Wang, Shouhua; Liu, Jun; Ma, Fei; Quan, Zhiwei

2017-05-01

Gallbladder cancer has poor prognosis and limited therapeutic options. Arctigenin, a representative dibenzylbutyrolactone lignan, occurs in a variety of plants. However, the molecular mechanisms involved in the antitumor effect of arctigenin on gallbladder cancer have not been fully elucidated. The expression levels of epidermal growth factor receptor were examined in 100 matched pairs of gallbladder cancer tissues. A positive correlation between high epidermal growth factor receptor expression levels and poor prognosis was observed in gallbladder cancer tissues. Pharmacological inhibition or inhibition via RNA interference of epidermal growth factor receptor induced cellular senescence in gallbladder cancer cells. The antitumor effect of arctigenin on gallbladder cancer cells was primarily achieved by inducing cellular senescence. In gallbladder cancer cells treated with arctigenin, the expression level of epidermal growth factor receptor significantly decreased. The analysis of the activity of the kinases downstream of epidermal growth factor receptor revealed that the RAF-MEK-ERK signaling pathway was significantly inhibited. Furthermore, the cellular senescence induced by arctigenin could be reverted by pcDNA-epidermal growth factor receptor. Arctigenin also potently inhibited the growth of tumor xenografts, which was accompanied by the downregulation of epidermal growth factor receptor and induction of senescence. This study demonstrates arctigenin could induce cellular senescence in gallbladder cancer through the modulation of epidermal growth factor receptor pathway. These data identify epidermal growth factor receptor as a key regulator in arctigenin-induced gallbladder cancer senescence.

Endothelial monocyte activating polypeptide-II modulates endothelial cell responses by degrading hypoxia-inducible factor-1alpha through interaction with PSMA7, a component of the proteasome

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tandle, Anita T.; Calvani, Maura; Uranchimeg, Badarch

The majority of human tumors are angiogenesis dependent. Understanding the specific mechanisms that contribute to angiogenesis may offer the best approach to develop therapies to inhibit angiogenesis in cancer. Endothelial monocyte activating polypeptide-II (EMAP-II) is an anti-angiogenic cytokine with potent effects on endothelial cells (ECs). It inhibits EC proliferation and cord formation, and it suppresses primary and metastatic tumor growth in-vivo. However, very little is known about the molecular mechanisms behind the anti-angiogenic activity of EMAP-II. In the present study, we explored the molecular mechanism behind the anti-angiogenic activity exerted by this protein on ECs. Our results demonstrate that EMAP-IImore » binds to the cell surface {alpha}5{beta}1 integrin receptor. The cell surface binding of EMAP-II results in its internalization into the cytoplasmic compartment where it interacts with its cytoplasmic partner PSMA7, a component of the proteasome degradation pathway. This interaction increases hypoxia-inducible factor 1-alpha (HIF-1{alpha}) degradation under hypoxic conditions. The degradation results in the inhibition of HIF-1{alpha} mediated transcriptional activity as well as HIF-1{alpha} mediated angiogenic sprouting of ECs. HIF-1{alpha} plays a critical role in angiogenesis by activating a variety of angiogenic growth factors. Our results suggest that one of the major anti-angiogenic functions of EMAP-II is exerted through its inhibition of the HIF-1{alpha} activities.« less

Redox-regulated growth factor survival signaling.

PubMed

Woolley, John F; Corcoran, Aoife; Groeger, Gillian; Landry, William D; Cotter, Thomas G

2013-11-20

Once the thought of as unwanted byproducts of cellular respiration in eukaryotes, reactive oxygen species (ROS) have been shown to facilitate essential physiological roles. It is now understood that ROS are critical mediators of intracellular signaling. Control of signal transduction downstream of growth factor receptors by ROS is a complex process whose details are only recently coming to light. Indeed, recent evidence points to control of signal propagation by ROS at multiple levels in the typical cascade. Growth factor stimulation activates nicotinamide adenine dinucleotide phosphate (NADPH) oxidases (Noxs) at the membrane, producing superoxide in the extracellular matrix, which is catalyzed to the membrane-permeable hydrogen peroxide (H2O2) that mediates intracellular signaling events. The potential for H2O2, however, to disrupt cellular functions by damaging proteins and nucleic acids demands that its levels are kept in check by receptor-associated peroxiredoxins. This interplay of Nox and peroxiredoxin activity moderates levels of H2O2 sufficiently to modify signaling partners locally. Among the best studied of these partners are redox-controlled phosphatases that are inactivated by H2O2. Phosphatases regulate signal propagation downstream of receptors, and thus their inactivation allows a further level of control. Transmission of information further downstream to targets such as transcription factors, themselves regulated by ROS, completes this pathway. Thus, signal propagation or attenuation can be dictated by ROS at multiple points. Given the complex nature of these processes, we envisage the emerging trends in the field of redox signaling in the context of growth factor stimulation.

Endosomal receptor kinetics determine the stability of intracellular growth factor signalling complexes

PubMed Central

Tzafriri, A. Rami; Edelman, Elazer R.

2006-01-01

There is an emerging paradigm that growth factor signalling continues in the endosome and that cell response to a growth factor is defined by the integration of cell surface and endosomal events. As activated receptors in the endosome are exposed to a different set of binding partners, they probably elicit differential signals compared with when they are at the cell surface. As such, complete appreciation of growth factor signalling requires understanding of growth factor–receptor binding and trafficking kinetics both at the cell surface and in endosomes. Growth factor binding to surface receptors is well characterized, and endosomal binding is assumed to follow surface kinetics if one accounts for changes in pH. Yet, specific binding kinetics within the endosome has not been examined in detail. To parse the factors governing the binding state of endosomal receptors we analysed a whole-cell mathematical model of epidermal growth factor receptor trafficking and binding. We discovered that the stability of growth factor–receptor complexes within endosomes is governed by three primary independent factors: the endosomal dissociation constant, total endosomal volume and the number of endosomal receptors. These factors were combined into a single dimensionless parameter that determines the endosomal binding state of the growth factor–receptor complex and can distinguish different growth factors from each other and different cell states. Our findings indicate that growth factor binding within endosomal compartments cannot be appreciated solely on the basis of the pH-dependence of the dissociation constant and that the concentration of receptors in the endosomal compartment must also be considered. PMID:17117924

Sex differences in the enhanced responsiveness to acute angiotensin II in growth-restricted rats: role of fasudil, a Rho kinase inhibitor

PubMed Central

Ojeda, Norma B.; Royals, Thomas P.

2013-01-01

This study tested the hypothesis that Rho kinase contributes to the enhanced pressor response to acute angiotensin II in intact male growth-restricted and gonadectomized female growth-restricted rats. Mean arterial pressure (MAP) and renal function were determined in conscious animals pretreated with enalapril (250 mg/l in drinking water) for 1 wk to block the endogenous renin-angiotensin system and normalize blood pressure (baseline). Blood pressure and renal hemodynamics did not differ at baseline. Acute Ang II (100 ng·kg−1·min−1) induced a greater increase in MAP and renal vascular resistance and enhanced reduction in glomerular filtration rate in intact male growth-restricted rats compared with intact male controls (P < 0.05). Cotreatment with the Rho kinase inhibitor fasudil (33 μg·kg−1·min−1) significantly attenuated these hemodynamic changes (P < 0.05), but it did not abolish the differential increase in blood pressure above baseline, suggesting that the impact of intrauterine growth restriction on blood pressure in intact male growth-restricted rats is independent of Rho kinase. Gonadectomy in conjunction with fasudil returned blood pressure back to baseline in male growth-restricted rats, and yet glomerular filtration rate remained significantly reduced (P < 0.05). Thus, these data suggest a role for enhanced renal sensitivity to acute Ang II in the developmental programming of hypertension in male growth-restricted rats. However, inhibition of Rho kinase had no effect on the basal or enhanced increase in blood pressure induced by acute Ang II in the gonadectomized female growth-restricted rat. Therefore, these studies suggest that Rho kinase inhibition exerts a sex-specific effect on blood pressure sensitivity to acute Ang II in growth-restricted rats. PMID:23344570

Sex differences in the enhanced responsiveness to acute angiotensin II in growth-restricted rats: role of fasudil, a Rho kinase inhibitor.

PubMed

Ojeda, Norma B; Royals, Thomas P; Alexander, Barbara T

2013-04-01

This study tested the hypothesis that Rho kinase contributes to the enhanced pressor response to acute angiotensin II in intact male growth-restricted and gonadectomized female growth-restricted rats. Mean arterial pressure (MAP) and renal function were determined in conscious animals pretreated with enalapril (250 mg/l in drinking water) for 1 wk to block the endogenous renin-angiotensin system and normalize blood pressure (baseline). Blood pressure and renal hemodynamics did not differ at baseline. Acute Ang II (100 ng·kg(-1)·min(-1)) induced a greater increase in MAP and renal vascular resistance and enhanced reduction in glomerular filtration rate in intact male growth-restricted rats compared with intact male controls (P < 0.05). Cotreatment with the Rho kinase inhibitor fasudil (33 μg·kg(-1)·min(-1)) significantly attenuated these hemodynamic changes (P < 0.05), but it did not abolish the differential increase in blood pressure above baseline, suggesting that the impact of intrauterine growth restriction on blood pressure in intact male growth-restricted rats is independent of Rho kinase. Gonadectomy in conjunction with fasudil returned blood pressure back to baseline in male growth-restricted rats, and yet glomerular filtration rate remained significantly reduced (P < 0.05). Thus, these data suggest a role for enhanced renal sensitivity to acute Ang II in the developmental programming of hypertension in male growth-restricted rats. However, inhibition of Rho kinase had no effect on the basal or enhanced increase in blood pressure induced by acute Ang II in the gonadectomized female growth-restricted rat. Therefore, these studies suggest that Rho kinase inhibition exerts a sex-specific effect on blood pressure sensitivity to acute Ang II in growth-restricted rats.

EGFR Ligands Drive Multipotential Stromal Cells to Produce Multiple Growth Factors and Cytokines via Early Growth Response-1

PubMed Central

Kerpedjieva, Svetoslava S.; Kim, Duk Soo; Barbeau, Dominique J.

2012-01-01

Cell therapy with adult bone marrow multipotential stromal cells/mesenchymal stem cells (MSCs) presents a promising approach to promote wound healing and tissue regeneration. The strong paracrine capability of various growth factors and cytokines is a key mechanism of MSC-mediated wound healing and tissue regeneration, and the goal of this study is to understand the underlying mechanism that supports the strong paracrine machineries in MSCs. Microarray database analyses revealed that early growth response-1 (EGR1) is highly expressed in MSCs. Our previous studies showed that epidermal growth factor (EGF) treatment induces growth factor production in MSCs in vitro. Since EGF strongly upregulates EGR1, we hypothesized that EGF receptor (EGFR)–EGR1 signaling plays a pivotal role in MSC paracrine activity. EGF treatment upregulated the gene expression of growth factors and cytokines, including EGFR ligands in a protein kinase C (PKC)- and/or mitogen-activated protein kinase–extracellular-signal-regulated kinase-dependent manner, and it was reversed by shRNA against EGR1. PKC activator phorbol 12-myristate 13-acetate enhanced EGFR tyrosyl phosphorylation and upregulated the gene expression of growth factors and cytokines in a heparin-binding EGF-like growth factor (HBEGF) inhibitor CRM197 sensitive manner, indicating an involvement of autocrined HBEGF in the downstream of PKC signaling. Moreover, stimulation with growth factors and cytokines induced the expression of EGFR ligands, presumably via EGR1 upregulation. These data indicate EGR1 as a convergence point of multiple signaling pathways, which in turn augments the production of multiple growth factors and cytokines by enhancing the autocrine signaling with EGFR ligands. PMID:22316125

The glial growth factors deficiency and synaptic destabilization hypothesis of schizophrenia

PubMed Central

Moises, Hans W; Zoega, Tomas; Gottesman, Irving I

2002-01-01

Background A systems approach to understanding the etiology of schizophrenia requires a theory which is able to integrate genetic as well as neurodevelopmental factors. Presentation of the hypothesis Based on a co-localization of loci approach and a large amount of circumstantial evidence, we here propose that a functional deficiency of glial growth factors and of growth factors produced by glial cells are among the distal causes in the genotype-to-phenotype chain leading to the development of schizophrenia. These factors include neuregulin, insulin-like growth factor I, insulin, epidermal growth factor, neurotrophic growth factors, erbB receptors, phosphatidylinositol-3 kinase, growth arrest specific genes, neuritin, tumor necrosis factor alpha, glutamate, NMDA and cholinergic receptors. A genetically and epigenetically determined low baseline of glial growth factor signaling and synaptic strength is expected to increase the vulnerability for additional reductions (e.g., by viruses such as HHV-6 and JC virus infecting glial cells). This should lead to a weakening of the positive feedback loop between the presynaptic neuron and its targets, and below a certain threshold to synaptic destabilization and schizophrenia. Testing the hypothesis Supported by informed conjectures and empirical facts, the hypothesis makes an attractive case for a large number of further investigations. Implications of the hypothesis The hypothesis suggests glial cells as the locus of the genes-environment interactions in schizophrenia, with glial asthenia as an important factor for the genetic liability to the disorder, and an increase of prolactin and/or insulin as possible working mechanisms of traditional and atypical neuroleptic treatments. PMID:12095426

Oligomeric state regulated trafficking of human platelet-activating factor acetylhydrolase type-II.

PubMed

Monillas, Elizabeth S; Caplan, Jeffrey L; Thévenin, Anastasia F; Bahnson, Brian J

2015-05-01

The intracellular enzyme platelet-activating factor acetylhydrolase type-II (PAFAH-II) hydrolyzes platelet-activating factor and oxidatively fragmented phospholipids. PAFAH-II in its resting state is mainly cytoplasmic, and it responds to oxidative stress by becoming increasingly bound to endoplasmic reticulum and Golgi membranes. Numerous studies have indicated that this enzyme is essential for protecting cells from oxidative stress induced apoptosis. However, the regulatory mechanism of the oxidative stress response by PAFAH-II has not been fully resolved. Here, changes to the oligomeric state of human PAFAH-II were investigated as a potential regulatory mechanism toward enzyme trafficking. Native PAGE analysis in vitro and photon counting histogram within live cells showed that PAFAH-II is both monomeric and dimeric. A Gly-2-Ala site-directed mutation of PAFAH-II demonstrated that the N-terminal myristoyl group is required for homodimerization. Additionally, the distribution of oligomeric PAFAH-II is distinct within the cell; homodimers of PAFAH-II were localized to the cytoplasm while monomers were associated to the membranes of the endoplasmic reticulum and Golgi. We propose that the oligomeric state of PAFAH-II drives functional protein trafficking. PAFAH-II localization to the membrane is critical for substrate acquisition and effective oxidative stress protection. It is hypothesized that the balance between monomer and dimer serves as a regulatory mechanism of a PAFAH-II oxidative stress response. Copyright © 2015 Elsevier B.V. All rights reserved.

Increased expression of placental growth factor in high-grade endometrial carcinoma

PubMed Central

COENEGRACHTS, LIEVE; SCHRAUWEN, STEFANIE; VAN BREE, RITA; DESPIERRE, EVELYN; LUYTEN, CATHERINE; JONCKX, BART; STASSEN, JEAN MARIE; VERGOTE, IGNACE; AMANT, FRÉDÉRIC

2013-01-01

Placental growth factor (PlGF), a homolog of vascular endothelial growth factor (VEGF), exerts pleiotropic functions in cancer by affecting tumor cells as well as endothelial and inflammatory cells. Moreover, PlGF expression correlates with tumor stage, recurrence, metastasis and patient outcome in different types of cancer. Recently, administration of anti-PlGF therapy reduced tumor growth and metastasis in preclinical tumor models. In the present study, we evaluated the diagnostic and prognostic value of systemic and local expression of PlGF in primary endometrial carcinomas. PlGF levels in tumor lysates (n=128) and serum (n=88) of patients with primary endometrial cancer were determined using ELISA. PlGF mRNA expression in endometrial carcinoma tissues was quantified by quantitative qRT-PCR. Results were compared to endometrial cancer stage and grade. Systemic PlGF levels were not altered in patients with endometrial cancer (FIGO stage I-II-III) as compared to healthy controls. Only in FIGO stage IV patients, serum PlGF levels were slightly increased. Local PlGF mRNA and protein expression in endometrial tumors progressively increased with tumor grade. In endometrioid carcinomas, PlGF mRNA expression was significantly increased in endometrioid grade 3 tumors as compared to normal endometrial tissue. PlGF protein expression was significantly increased in endometrioid grade 2 and 3 carcinomas and in serous carcinomas as compared to normal endometrial tissue. Our study showed that systemic/serum PlGF levels cannot be used as a diagnostic or prognostic marker in endometrial cancer. However, the increased local expression of PlGF, primarily in high-grade carcinomas, underscores the possibility for preclinical assessment of anti-PlGF therapy in endometrial cancer. PMID:23232836

Growth-differentiation factor 15 and osteoprotegerin in acute myocardial infarction complicated by cardiogenic shock: a biomarker substudy of the IABP-SHOCK II-trial.

PubMed

Fuernau, Georg; Poenisch, Christian; Eitel, Ingo; de Waha, Suzanne; Desch, Steffen; Schuler, Gerhard; Adams, Volker; Werdan, Karl; Zeymer, Uwe; Thiele, Holger

2014-08-01

This study investigates the role of osteoprotegerin (OPG) and growth-differentiation factor 15 (GDF-15) as predictors of outcome in cardiogenic shock (CS) complicating acute myocardial infarction. The novel biomarkers OPG and GDF-15 have shown prognostic impact in various cardiovascular diseases including myocardial infarction. In acute myocardial infarction complicated by CS, the diagnostic and prognostic impact of these biomarkers has not been investigated yet. OPG and GDF-15 may have additional prognostic impact on early prognosis assessment, being potentially useful for decision-making in CS. In the randomized Intra-aortic Balloon Pump in cardiogenic Shock II (IABP-SHOCK II)-trial, 600 patients with CS complicating acute myocardial infarction undergoing early revascularization were assigned to therapy with or without IABP. Within a pre-defined substudy, blood samples were collected from 190 patients during PCI. GDF-15 and OPG serum levels were measured with standard enzyme-linked immunosorbent assay kits. Patients with GDF-15 and OPG levels greater than the median showed higher rates of death at 30 days by χ(2) testing (OPG, 51% vs. 32%, P = 0.01; GDF-15, 52% vs. 31%, P = 0.005) and log rank testing [GDF-15, hazard ratio (HR) 1.88, 95% confidence interval (CI) 1.21-2.94; P = 0.005; OPG, HR 1.74, 95% CI 1.11-2.71; P = 0.01]. Both markers were significantly predictive of 30-day mortality in univariable logistic regression analysis. In a multivariable logistic stepwise regression model, GDF-15, TIMI (Thrombolysis In Myocardial Infarction) flow grade <3 after PCI, age, LVEF, and serum lactate remained significant predictors of 30-day mortality. GDF-15 on admission is a significant independent predictor of short-term mortality in infarct-related CS. Trail registration: NCT00491036. © 2014 The Authors. European Journal of Heart Failure © 2014 European Society of Cardiology.

The Effects of Hematopoietic Growth Factors on Neurite Outgrowth

PubMed Central

Su, Ye; Cui, Lili; Piao, Chunshu; Li, Bin; Zhao, Li-Ru

2013-01-01

Stem cell factor (SCF) and granulocyte colony-stimulating factor (G-CSF) are initially discovered as the essential hematopoietic growth factors regulating bone marrow stem cell proliferation and differentiation, and SCF in combination with G-CSF (SCF+G-CSF) has synergistic effects on bone marrow stem cell mobilization. In this study we have determined the effect of SCF and G-CSF on neurite outgrowth in rat cortical neurons. Using molecular and cellular biology and live cell imaging approaches, we have revealed that receptors for SCF and G-CSF are expressed on the growth core of cortical neurons, and that SCF+G-CSF synergistically enhances neurite extension through PI3K/AKT and NFκB signaling pathways. Moreover, SCF+G-CSF induces much greater NFκB activation, NFκB transcriptional binding and brain-derived neurotrophic factor (BDNF) production than SCF or G-CSF alone. In addition, we have also observed that BDNF, the target gene of NFκB, is required for SCF+G-CSF-induced neurite outgrowth. These data suggest that SCF+G-CSF has synergistic effects to promote neurite growth. This study provides new insights into the contribution of hematopoietic growth factors in neuronal plasticity. PMID:24116056

Normal growth and development in the absence of hepatic insulin-like growth factor I

PubMed Central

Yakar, Shoshana; Liu, Jun-Li; Stannard, Bethel; Butler, Andrew; Accili, Domenici; Sauer, Brian; LeRoith, Derek

1999-01-01

The somatomedin hypothesis proposed that insulin-like growth factor I (IGF-I) was a hepatically derived circulating mediator of growth hormone and is a crucial factor for postnatal growth and development. To reassess this hypothesis, we have used the Cre/loxP recombination system to delete the igf1 gene exclusively in the liver. igf1 gene deletion in the liver abrogated expression of igf1 mRNA and caused a dramatic reduction in circulating IGF-I levels. However, growth as determined by body weight, body length, and femoral length did not differ from wild-type littermates. Although our model proves that hepatic IGF-I is indeed the major contributor to circulating IGF-I levels in mice it challenges the concept that circulating IGF-I is crucial for normal postnatal growth. Rather, our model provides direct evidence for the importance of the autocrine/paracrine role of IGF-I. PMID:10377413

Insulin-like growth factor 1 (IGF-1): a growth hormone

PubMed Central

Laron, Z

2001-01-01

Aim—To contribute to the debate about whether growth hormone (GH) and insulin-like growth factor 1 (IGF-1) act independently on the growth process. Methods—To describe growth in human and animal models of isolated IGF-1 deficiency (IGHD), such as in Laron syndrome (LS; primary IGF-1 deficiency and GH resistance) and IGF-1 gene or GH receptor gene knockout (KO) mice. Results—Since the description of LS in 1966, 51 patients were followed, many since infancy. Newborns with LS are shorter (42–47 cm) than healthy babies (49–52 cm), suggesting that IGF-1 has some influence on intrauterine growth. Newborn mice with IGF-1 gene KO are 30% smaller. The postnatal growth rate of patients with LS is very slow, the distance from the lowest normal centile increasing progressively. If untreated, the final height is 100–136 cm for female and 109–138 cm for male patients. They have acromicia, organomicria including the brain, heart, gonads, genitalia, and retardation of skeletal maturation. The availability of biosynthetic IGF-1 since 1988 has enabled it to be administered to children with LS. It accelerated linear growth rates to 8–9 cm in the first year of treatment, compared with 10–12 cm/year during GH treatment of IGHD. The growth rate in following years was 5–6.5 cm/year. Conclusion—IGF-1 is an important growth hormone, mediating the protein anabolic and linear growth promoting effect of pituitary GH. It has a GH independent growth stimulating effect, which with respect to cartilage cells is possibly optimised by the synergistic action with GH. PMID:11577173

Increased Melanoma Growth and Metastasis Spreading in Mice Overexpressing Placenta Growth Factor

PubMed Central

Marcellini, Marcella; De Luca, Naomi; Riccioni, Teresa; Ciucci, Alessandro; Orecchia, Angela; Lacal, Pedro Miguel; Ruffini, Federica; Pesce, Maurizio; Cianfarani, Francesca; Zambruno, Giovanna; Orlandi, Augusto; Failla, Cristina Maria

2006-01-01

Placenta growth factor (PlGF), a member of the vascular endothelial growth factor family, plays an important role in adult pathological angiogenesis. To further investigate PlGF functions in tumor growth and metastasis formation, we used transgenic mice overexpressing PlGF in the skin under the control of the keratin 14 promoter. These animals showed a hypervascularized phenotype of the skin and increased levels of circulating PlGF with respect to their wild-type littermates. Transgenic mice and controls were inoculated intradermally with B16-BL6 melanoma cells. The tumor growth rate was fivefold increased in transgenic animals compared to wild-type mice, in the presence of a similar percentage of tumor necrotic tissue. Tumor vessel area was increased in transgenic mice as compared to controls. Augmented mobilization of endothelial and hematopoietic stem cells from the bone marrow was observed in transgenic animals, possibly contributing to tumor vascularization. The number and size of pulmonary metastases were significantly higher in transgenic mice compared to wild-type littermates. Finally, PlGF promoted tumor cell invasion of the extracellular matrix and increased the activity of selected matrix metalloproteinases. These findings indicate that PlGF, in addition to enhancing tumor angiogenesis and favoring tumor growth, may directly influence melanoma dissemination. PMID:16877362

Autocrine expression of the epidermal growth factor receptor ligand heparin-binding EGF-like growth factor in cervical cancer.

PubMed

Schrevel, Marlies; Osse, E Michelle; Prins, Frans A; Trimbos, J Baptist M Z; Fleuren, Gert Jan; Gorter, Arko; Jordanova, Ekaterina S

2017-06-01

In cervical cancer, the epidermal growth factor receptor (EGFR) is overexpressed in 70-90% of the cases and has been associated with poor prognosis. EGFR-based therapy is currently being explored in cervical cancer. We investigated which EGFR ligand is primarily expressed in cervical cancer and which cell type functions as the major source of this ligand. We hypothesized that macrophages are the main source of EGFR ligands and that a paracrine loop between tumor cells and macrophages is responsible for ligand expression. mRNA expression analysis was performed on 32 cervical cancer cases to determine the expression of the EGFR ligands amphiregulin, β-cellulin, epidermal growth factor (EGF), epiregulin, heparin-binding EGF-like growth factor (HB‑EGF) and transforming growth factor α (TGFα). Subsequently, protein expression was determined immunohistochemically on 36 additional cases. To assess whether macrophages are the major source of EGFR ligands, immunohistochemical double staining was performed on four representative tissue slides. Expression of the chemokines granulocyte-macrophage colony-stimulating factor (GM-CSF) and C-C motif ligand 2 (CCL2) was determined by mRNA in situ hybridization. Of the known EGFR ligands, HB‑EGF had the highest mRNA expression and HB‑EGF and EGFR protein expression were highly correlated. Tumor specimens with high EGFR expression showed higher numbers of macrophages, and higher expression of GM-CSF and CCL2, but only a small subset (9%) of macrophages was found to be HB‑EGF-positive. Strikingly, 78% of cervical cancer specimens were found to express HB‑EGF. Standardized assessment of staining intensity, using spectral imaging analysis, showed that HB‑EGF expression was higher in the tumor compartment than in the stromal compartment. These results suggest that HB‑EGF is an important EGFR ligand in cervical cancer and that cervical cancer cells are the predominant source of HB‑EGF. Therefore, we propose an autocrine

Mitochondrial respiratory control is lost during growth factor deprivation.

PubMed

Gottlieb, Eyal; Armour, Sean M; Thompson, Craig B

2002-10-01

The ability of cells to maintain a bioenergetically favorable ATP/ADP ratio confers a tight balance between cellular events that consume ATP and the rate of ATP production. However, after growth factor withdrawal, the cellular ATP/ADP ratio declines. To investigate these changes, mitochondria from growth factor-deprived cells isolated before the onset of apoptosis were characterized in vitro. Mitochondria from growth factor-deprived cells have lost their ability to undergo matrix condensation in response to ADP, which is accompanied by a failure to perform ADP-coupled respiration. At the time of analysis, mitochondria from growth factor-deprived cells were not depleted of cytochrome c and cytochrome c-dependent respiration was unaffected, demonstrating that the inhibition of the respiratory rate is not due to loss of cytochrome c. Agents that disrupt the mitochondrial outer membrane, such as digitonin, or maintain outer membrane exchange of adenine nucleotide, such as Bcl-x(L), restored ADP-dependent control of mitochondrial respiration. Together, these data suggest that the regulation of mitochondrial outer membrane permeability contributes to respiratory control.

Mitochondrial respiratory control is lost during growth factor deprivation

PubMed Central

Gottlieb, Eyal; Armour, Sean M.; Thompson, Craig B.

2002-01-01

The ability of cells to maintain a bioenergetically favorable ATP/ADP ratio confers a tight balance between cellular events that consume ATP and the rate of ATP production. However, after growth factor withdrawal, the cellular ATP/ADP ratio declines. To investigate these changes, mitochondria from growth factor-deprived cells isolated before the onset of apoptosis were characterized in vitro. Mitochondria from growth factor-deprived cells have lost their ability to undergo matrix condensation in response to ADP, which is accompanied by a failure to perform ADP-coupled respiration. At the time of analysis, mitochondria from growth factor-deprived cells were not depleted of cytochrome c and cytochrome c-dependent respiration was unaffected, demonstrating that the inhibition of the respiratory rate is not due to loss of cytochrome c. Agents that disrupt the mitochondrial outer membrane, such as digitonin, or maintain outer membrane exchange of adenine nucleotide, such as Bcl-xL, restored ADP-dependent control of mitochondrial respiration. Together, these data suggest that the regulation of mitochondrial outer membrane permeability contributes to respiratory control. PMID:12228733

Surface stability and the selection rules of substrate orientation for optimal growth of epitaxial II-VI semiconductors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yin, Wan-Jian; Department of Physics & Astronomy, and Wright Center for Photovoltaics Innovation and Commercialization, The University of Toledo, Toledo, Ohio 43606; Yang, Ji-Hui

2015-10-05

The surface structures of ionic zinc-blende CdTe (001), (110), (111), and (211) surfaces are systematically studied by first-principles density functional calculations. Based on the surface structures and surface energies, we identify the detrimental twinning appearing in molecular beam epitaxy (MBE) growth of II-VI compounds as the (111) lamellar twin boundaries. To avoid the appearance of twinning in MBE growth, we propose the following selection rules for choosing optimal substrate orientations: (1) the surface should be nonpolar so that there is no large surface reconstructions that could act as a nucleation center and promote the formation of twins; (2) the surfacemore » structure should have low symmetry so that there are no multiple equivalent directions for growth. These straightforward rules, in consistent with experimental observations, provide guidelines for selecting proper substrates for high-quality MBE growth of II-VI compounds.« less

Powerful inhibition of in-vivo growth of experimental hepatic cancers by bombesin/gastrin-releasing peptide antagonist RC-3940-II.

PubMed

Szepeshazi, Karoly; Schally, Andrew V; Rick, Ferenc G; Block, Norman L; Vidaurre, Irving; Halmos, Gabor; Szalontay, Luca

2012-10-01

Hepatic carcinoma is a major health problem worldwide. Its incidence is increasing in Western countries and there is currently no effective systemic therapy against it. Targeted treatment modalities developed in the past few years have provided very limited success. Development of new treatment strategies is therefore essential. We investigated the effects of bombesin/gastrin-releasing peptide (BN/GRP) antagonist RC-3940-II on experimental human liver cancers in nude mice. SK-Hep-1 and Hep-G2 cancers transplanted subcutaneously into nude mice were treated daily with 10 or 20 µg of RC-3940-II. Tumor growth was monitored for 50-184 days in five experiments. Tumor gene expression was analyzed with PCR array and protein expression by immunoblotting. Characteristics of BN/GRP receptors in the tumors were analyzed by binding assays. Effects of RC-3940-II on cell proliferation were investigated in vitro. RC-3940-II inhibited the growth of SK-Hep-1 cancers in nude mice by 65-98%, with total regression in 9 of 36 tumors in three experiments. The BN/GRP antagonist inhibited the growth of Hep-G2 cancers as well by 73-82% in two experiments, being effective even on originally large tumors. Gene expression analysis showed an increase in several angiogenesis inhibitors and decrease in proangiogenic genes after RC-3940-II treatment. Receptor assays demonstrated high-affinity binding sites for BN/GRP in both tumor lines. BN/GRP antagonist RC-3940-II powerfully inhibits growth of SK-Hep-1 and Hep-G2 cancers in nude mice. Its effect may be linked to changes in expression of those cancer genes important in angiogenesis, invasion, and metastasis. RC-3940-II may be considered for further investigations in treatment of liver cancers.

E2F1 transcription factor and its impact on growth factor and cytokine signaling.

PubMed

Ertosun, Mustafa Gokhan; Hapil, Fatma Zehra; Osman Nidai, Ozes

2016-10-01

E2F1 is a transcription factor involved in cell cycle regulation and apoptosis. The transactivation capacity of E2F1 is regulated by pRb. In its hypophosphorylated form, pRb binds and inactivates DNA binding and transactivating functions of E2F1. The growth factor stimulation of cells leads to activation of CDKs (cyclin dependent kinases), which in turn phosphorylate Rb and hyperphosphorylated Rb is released from E2F1 or E2F1/DP complex, and free E2F1 can induce transcription of several genes involved in cell cycle entry, induction or inhibition of apoptosis. Thus, growth factors and cytokines generally utilize E2F1 to direct cells to either fate. Furthermore, E2F1 regulates expressions of various cytokines and growth factor receptors, establishing positive or negative feedback mechanisms. This review focuses on the relationship between E2F1 transcription factor and cytokines (IL-1, IL-2, IL-3, IL-6, TGF-beta, G-CSF, LIF), growth factors (EGF, KGF, VEGF, IGF, FGF, PDGF, HGF, NGF), and interferons (IFN-α, IFN-β and IFN-γ). Copyright © 2016 Elsevier Ltd. All rights reserved.

Natural Killer Cells Control Tumor Growth by Sensing a Growth Factor.

PubMed

Barrow, Alexander D; Edeling, Melissa A; Trifonov, Vladimir; Luo, Jingqin; Goyal, Piyush; Bohl, Benjamin; Bando, Jennifer K; Kim, Albert H; Walker, John; Andahazy, Mary; Bugatti, Mattia; Melocchi, Laura; Vermi, William; Fremont, Daved H; Cox, Sarah; Cella, Marina; Schmedt, Christian; Colonna, Marco

2018-01-25

Many tumors produce platelet-derived growth factor (PDGF)-DD, which promotes cellular proliferation, epithelial-mesenchymal transition, stromal reaction, and angiogenesis through autocrine and paracrine PDGFRβ signaling. By screening a secretome library, we found that the human immunoreceptor NKp44, encoded by NCR2 and expressed on natural killer (NK) cells and innate lymphoid cells, recognizes PDGF-DD. PDGF-DD engagement of NKp44 triggered NK cell secretion of interferon gamma (IFN)-γ and tumor necrosis factor alpha (TNF-α) that induced tumor cell growth arrest. A distinctive transcriptional signature of PDGF-DD-induced cytokines and the downregulation of tumor cell-cycle genes correlated with NCR2 expression and greater survival in glioblastoma. NKp44 expression in mouse NK cells controlled the dissemination of tumors expressing PDGF-DD more effectively than control mice, an effect enhanced by blockade of the inhibitory receptor CD96 or CpG-oligonucleotide treatment. Thus, while cancer cell production of PDGF-DD supports tumor growth and stromal reaction, it concomitantly activates innate immune responses to tumor expansion. Copyright © 2017 Elsevier Inc. All rights reserved.

Skeletal Effects of Growth Hormone and Insulin-like Growth Factor-I Therapy

PubMed Central

Lindsey, Richard C.; Mohan, Subburaman

2015-01-01

The growth hormone/insulin-like growth factor (GH/IGF) axis is critically important for the regulation of bone formation, and deficiencies in this system have been shown to contribute to the development of osteoporosis and other diseases of low bone mass. The GH/IGF axis is regulated by a complex set of hormonal and local factors which can act to regulate this system at the level of the ligands, receptors, IGF binding proteins (IGFBPs), or IGFBP proteases. A combination of in vitro studies, transgenic animal models, and clinical human investigations has provided ample evidence of the importance of the endocrine and local actions of both GH and IGF-I, the two major components of the GH/IGF axis, in skeletal growth and maintenance. GH- and IGF-based therapies provide a useful avenue of approach for the prevention and treatment of diseases such as osteoporosis. PMID:26408965

Stimulation of body weight increase and epiphyseal cartilage growth by insulin like growth factor

NASA Technical Reports Server (NTRS)

Ellis, S.

1981-01-01

The ability of insulin-like growth factor (IGF) to induce growth in hypophysectomized immature rats was tested by continuous infusion of the partially purified factor at daily doses of 6, 21, and 46 mU for an 8-day period. A dose-dependent growth of the proximal epiphyseal cartilage of the tibia and an associated stimulation of the primary spongiosa were produced by these amounts of IGF. The two highest doses of IGF also resulted in dose-dependent increases of body weight. Gel permeation of the sera at neutrality showed that the large-molecular-weight IGF binding protein was not induced by the infusion of IGF, whereas it ws generated in the sera of hypophysectomized rats that were infused with daily doses of 86 mU of human growth hormone.

Effects of methionine deficiencies on plasma levels of thyroid hormones, insulin-like growth factors-I and -II, liver and body weights, and feed intake in growing chickens.

PubMed

Carew, L B; McMurtry, J P; Alster, F A

2003-12-01

We showed previously that Met deficiency at 0.25% of the diet causes elevations in plasma triiodothyronine (T3) in broilers. In the present study, plasma levels of thyroid hormones as well as insulin-like growth factors (IGF)-I and -II were measured in chicks fed 3 deficient levels of total Met. Control (0.5%) and Met-deficient diets (0.4, 0.3, and 0.2%) were fed to male broilers from 8 to 22 d of age. Additional groups of control chicks were pair-fed with the Met-deficient ones. Chicks receiving 0.4% Met increased feed intake by 10% with no significant change in body weight. The more severe Met deficiencies of 0.3 and 0.2% caused graded reductions in feed intake and weight gain. However, corresponding pair-fed control chicks were significantly heavier. These changes suggest more marked alterations in metabolic processes with 0.3 and 0.2% Met than with 0.4% Met. Liver weights were heavier in chicks fed 0.3 and 0.2% Met but not 0.4%. Plasma T3 was higher in all deficient chicks compared with the free-fed control, which was significant only with 0.3% Met. However, with 0.3 and 0.2% Met, plasma T3 was significantly elevated compared to pair-fed controls. Plasma thyroxine (T4) was lower in all deficient groups, which was significant only with 0.2% Met, whereas no significant differences occurred between deficient chicks and their pair-fed controls. Plasma IGF-I levels were not significantly different, but they were consistently lower in deficient chicks and deserve further study. Plasma IGF-II was significantly less in chicks fed 0.2% Met compared to pair-fed controls suggesting that Met deficiency interferes with IGF-II metabolism. We concluded that a deficit of dietary Met altered plasma T3 and IGF-II levels, but the effect was dependent on the degree of deficiency.

Loss of insulin-like growth factor II imprinting is a hallmark associated with enhanced chemo/radiotherapy resistance in cancer stem cells.

PubMed

Zhao, Xin; Liu, Xiaoliang; Wang, Guanjun; Wen, Xue; Zhang, Xiaoying; Hoffman, Andrew R; Li, Wei; Hu, Ji-Fan; Cui, Jiuwei

2016-08-09

Insulin-like growth factor II (IGF2) is maternally imprinted in most tissues, but the epigenetic regulation of the gene in cancer stem cells (CSCs) has not been defined. To study the epigenetic mechanisms underlying self-renewal, we isolated CSCs and non-CSCs from colon cancer (HT29, HRT18, HCT116), hepatoma (Hep3B), breast cancer (MCF7) and prostate cancer (ASPC) cell lines. In HT29 and HRT18 cells that show loss of IGF2 imprinting (LOI), IGF2 was biallelically expressed in the isolated CSCs. Surprisingly, we also found loss of IGF2 imprinting in CSCs derived from cell lines HCT116 and ASPC that overall demonstrate maintenance of IGF2 imprinting. Using chromatin conformation capture (3C), we found that intrachromosomal looping between the IGF2 promoters and the imprinting control region (ICR) was abrogated in CSCs, in parallel with loss of IGF2 imprinting in these CSCs. Loss of imprinting led to increased IGF2 expression in CSCs, which have a higher rate of colony formation and greater resistance to chemotherapy and radiotherapy in vitro. These studies demonstrate that IGF2 LOI is a common feature in CSCs, even when the stem cells are derived from a cell line in which the general population of cells maintain IGF2 imprinting. This finding suggests that aberrant IGF2 imprinting may be an intrinsic epigenetic control mechanism that enhances stemness, self-renewal and chemo/radiotherapy resistance in cancer stem cells.

Combination of two insulin-like growth factor-I receptor inhibitory antibodies targeting distinct epitopes leads to an enhanced antitumor response.

PubMed

Dong, Jianying; Demarest, Stephen J; Sereno, Arlene; Tamraz, Susan; Langley, Emma; Doern, Adam; Snipas, Tracey; Perron, Keli; Joseph, Ingrid; Glaser, Scott M; Ho, Steffan N; Reff, Mitchell E; Hariharan, Kandasamy

2010-09-01

The insulin-like growth factor-I receptor (IGF-IR) is a cell surface receptor tyrosine kinase that mediates cell survival signaling and supports tumor progression in multiple tumor types. We identified a spectrum of inhibitory IGF-IR antibodies with diverse binding epitopes and ligand-blocking properties. By binding distinct inhibitory epitopes, two of these antibodies, BIIB4 and BIIB5, block both IGF-I and IGF-II binding to IGF-IR using competitive and allosteric mechanisms, respectively. Here, we explored the inhibitory effects of combining BIIB4 and BIIB5. In biochemical assays, the combination of BIIB4 and BIIB5 improved both the potency and extent of IGF-I and IGF-II blockade compared with either antibody alone. In tumor cells, the combination of BIIB4 and BIIB5 accelerated IGF-IR downregulation and more efficiently inhibited IGF-IR activation as well as downstream signaling, particularly AKT phosphorylation. In several carcinoma cell lines, the antibody combination more effectively inhibited ligand-driven cell growth than either BIIB4 or BIIB5 alone. Notably, the enhanced tumor growth-inhibitory activity of the BIIB4 and BIIB5 combination was much more pronounced at high ligand concentrations, where the individual antibodies exhibited substantially reduced activity. Compared with single antibodies, the BIIB4 and BIIB5 combination also significantly further enhanced the antitumor activity of the epidermal growth factor receptor inhibitor erlotinib and the mTOR inhibitor rapamycin. Moreover, in osteosarcoma and hepatocellular carcinoma xenograft models, the BIIB4 and BIIB5 combination significantly reduced tumor growth to a greater degree than each single antibody. Taken together, our results suggest that targeting multiple distinct inhibitory epitopes on IGF-IR may be a more effective strategy of affecting the IGF-IR pathway in cancer.

Ontogeny and nutritional programming of the hepatic growth hormone-insulin-like growth factor-prolactin axis in the sheep.

PubMed

Hyatt, Melanie A; Budge, Helen; Walker, David; Stephenson, Terence; Symonds, Michael E

2007-10-01

The liver is an important metabolic and endocrine organ in the fetus, but the extent to which its hormone receptor sensitivity is developmentally regulated in early life is not fully established. Therefore, we examined developmental changes in mRNA abundance for the GH receptor (GHR) and prolactin receptor (PRLR) plus IGF-I and -II and their receptors. Fetal and postnatal sheep were sampled at either 80 or 140 d gestation, 1 or 30 d, or 6 months of age. The effect of maternal nutrient restriction between early gestation to midgestation (i.e. 28-80 d gestation, the time of early liver growth) on gene expression was also examined in the fetus and juvenile offspring. Gene expression for the GHR, PRLR, and IGF-I receptor increased through gestation peaking at birth, whereas IGF-I was maximal near to term. In contrast, IGF-II mRNA decreased between midgestation and late gestation to increase after birth, whereas IGF-II receptor remained unchanged. A substantial decline in mRNA abundance for GHR, PRLR, and IGF-I receptor then occurred up to 6 months. Maternal nutrient restriction reduced GHR and IGF-II receptor mRNA abundance in the fetus, but caused a precocious increase in the PRLR. Gene expression for IGF-I and -II were increased in juvenile offspring born to nutrient-restricted mothers. In conclusion, there are marked differences in the ontogeny and nutritional programming of specific hormones and their receptors involved in hepatic growth and development in the fetus. These could contribute to changes in liver function during adult life.

Self-organized MBE growth of II VI epilayers on patterned GaSb substrates

NASA Astrophysics Data System (ADS)

Wissmann, H.; Tran Anh, T.; Rogaschewski, S.; von Ortenberg, M.

1999-05-01

We report on the self-organized MBE growth of II-VI epilayers on patterned and unpatterned GaSb substrates resulting in quantum wires and quantum wells, respectively. The HgSe : Fe quantum wires were grown on (0 0 1)GaSb substrates with a buffer of lattice-matched ZnTe 1- xSe x. Due to the anisotropic growth of HgSe on the A-oriented stripes roof-like overgrowth with a definite ridge was obtained. Additional Fe doping in the direct vicinity of the ridge results in a highly conductive quantum wire.

Growth factor delivery: How surface interactions modulate release in vitro and in vivo

PubMed Central

King, William J.; Krebsbach, Paul H.

2013-01-01

Biomaterial scaffolds have been extensively used to deliver growth factors to induce new bone formation. The pharmacokinetics of growth factor delivery has been a critical regulator of their clinical success. This review will focus on the surface interactions that control the non-covalent incorporation of growth factors into scaffolds and the mechanisms that control growth factor release from clinically relevant biomaterials. We will focus on the delivery of recombinant human bone morphogenetic protein-2 from materials currently used in the clinical practice, but also suggest how general mechanisms that control growth factor incorporation and release delineated with this growth factor could extend to other systems. A better understanding of the changing mechanisms that control growth factor release during the different stages of preclinical development could instruct the development of future scaffolds for currently untreatable injuries and diseases. PMID:22433783

Growth Hormone and Insulin-Like Growth Factor-1.

PubMed

Nicholls, Adam R; Holt, Richard I G

2016-01-01

Human growth hormone (GH) was first isolated from the human pituitary gland in 1945 and found to promote the growth of children with hypopituitarism. Since the formation of the World Anti-Doping Association, human GH has appeared on the list of forbidden substances. There is a significant amount of anecdotal evidence that human GH is misused by athletes to enhance performance, and there have been a number of high-profile cases of GH use in professional sport. GH secretagogues (GH-Ss), which increase GH secretion, and insulin-like growth factor (IGF-1), which mediates many of the effects of GH, are also misused, although there is less evidence for this. The effectiveness of GH, IGF-1, and GH-Ss as performance-enhancing drugs remains unclear. Evidence from studies of GH use in people with hypopituitarism show several desirable outcomes, including increased lean body mass, increased strength, and increased exercise capacity. These anabolic and metabolic properties, coupled with the difficulty in detecting them, make them attractive as agents of misuse. Studies in healthy young adults have also demonstrated a performance benefit with GH and IGF-1. © 2016 S. Karger AG, Basel.

Placental Growth Factor Administration Abolishes Placental Ischemia-Induced Hypertension.

PubMed

Spradley, Frank T; Tan, Adelene Y; Joo, Woo S; Daniels, Garrett; Kussie, Paul; Karumanchi, S Ananth; Granger, Joey P

2016-04-01

Preeclampsia is a pregnancy-specific disorder of new-onset hypertension. Unfortunately, the most effective treatment is early delivery of the fetus and placenta. Placental ischemia appears central to the pathogenesis of preeclampsia because placental ischemia/hypoxia induced in animals by reduced uterine perfusion pressure (RUPP) or in humans stimulates release of hypertensive placental factors into the maternal circulation. The anti-angiogenic factor soluble fms-like tyrosine kinase-1 (sFlt-1), which antagonizes and reduces bioavailable vascular endothelial growth factor and placental growth factor (PlGF), is elevated in RUPP rats and preeclampsia. Although PlGF and vascular endothelial growth factor are both natural ligands for sFlt-1, vascular endothelial growth factor also has high affinity to VEGFR2 (Flk-1) causing side effects like edema. PlGF is specific for sFlt-1. We tested the hypothesis that PlGF treatment reduces placental ischemia-induced hypertension by antagonizing sFlt-1 without adverse consequences to the mother or fetus. On gestational day 14, rats were randomized to 4 groups: normal pregnant or RUPP±infusion of recombinant human PlGF (180 μg/kg per day; AG31, a purified, recombinant human form of PlGF) for 5 days via intraperitoneal osmotic minipumps. On day 19, mean arterial blood pressure and plasma sFlt-1 were higher and glomerular filtration rate lower in RUPP than normal pregnant rats. Infusion of recombinant human PlGF abolished these changes seen with RUPP along with reducing oxidative stress. These data indicate that the increased sFlt-1 and reduced PlGF resulting from placental ischemia contribute to maternal hypertension. Our novel finding that recombinant human PlGF abolishes placental ischemia-induced hypertension, without major adverse consequences, suggests a strong therapeutic potential for this growth factor in preeclampsia. © 2016 American Heart Association, Inc.

Temporally controlled release of multiple growth factors from a self-assembling peptide hydrogel

NASA Astrophysics Data System (ADS)

Bruggeman, Kiara F.; Rodriguez, Alexandra L.; Parish, Clare L.; Williams, Richard J.; Nisbet, David R.

2016-09-01

Protein growth factors have demonstrated great potential for tissue repair, but their inherent instability and large size prevents meaningful presentation to biologically protected nervous tissue. Here, we create a nanofibrous network from a self-assembling peptide (SAP) hydrogel to carry and stabilize the growth factors. We significantly reduced growth factor degradation to increase their lifespan by over 40 times. To control the temporal release profile we covalently attached polysaccharide chitosan molecules to the growth factor to increase its interactions with the hydrogel nanofibers and achieved a 4 h delay, demonstrating the potential of this method to provide temporally controlled growth factor delivery. We also describe release rate based analysis to examine the growth factor delivery in more detail than standard cumulative release profiles allow and show that the chitosan attachment method provided a more consistent release profile with a 60% reduction in fluctuations. To prove the potential of this system as a complex growth factor delivery platform we demonstrate for the first time temporally distinct release of multiple growth factors from a single tissue specific SAP hydrogel: a significant goal in regenerative medicine.

Priming Dental Pulp Stem Cells With Fibroblast Growth Factor-2 Increases Angiogenesis of Implanted Tissue-Engineered Constructs Through Hepatocyte Growth Factor and Vascular Endothelial Growth Factor Secretion.

PubMed

Gorin, Caroline; Rochefort, Gael Y; Bascetin, Rumeyza; Ying, Hanru; Lesieur, Julie; Sadoine, Jérémy; Beckouche, Nathan; Berndt, Sarah; Novais, Anita; Lesage, Matthieu; Hosten, Benoit; Vercellino, Laetitia; Merlet, Pascal; Le-Denmat, Dominique; Marchiol, Carmen; Letourneur, Didier; Nicoletti, Antonino; Vital, Sibylle Opsahl; Poliard, Anne; Salmon, Benjamin; Muller, Laurent; Chaussain, Catherine; Germain, Stéphane

2016-03-01

Tissue engineering strategies based on implanting cellularized biomaterials are promising therapeutic approaches for the reconstruction of large tissue defects. A major hurdle for the reliable establishment of such therapeutic approaches is the lack of rapid blood perfusion of the tissue construct to provide oxygen and nutrients. Numerous sources of mesenchymal stem cells (MSCs) displaying angiogenic potential have been characterized in the past years, including the adult dental pulp. Establishment of efficient strategies for improving angiogenesis in tissue constructs is nevertheless still an important challenge. Hypoxia was proposed as a priming treatment owing to its capacity to enhance the angiogenic potential of stem cells through vascular endothelial growth factor (VEGF) release. The present study aimed to characterize additional key factors regulating the angiogenic capacity of such MSCs, namely, dental pulp stem cells derived from deciduous teeth (SHED). We identified fibroblast growth factor-2 (FGF-2) as a potent inducer of the release of VEGF and hepatocyte growth factor (HGF) by SHED. We found that FGF-2 limited hypoxia-induced downregulation of HGF release. Using three-dimensional culture models of angiogenesis, we demonstrated that VEGF and HGF were both responsible for the high angiogenic potential of SHED through direct targeting of endothelial cells. In addition, FGF-2 treatment increased the fraction of Stro-1+/CD146+ progenitor cells. We then applied in vitro FGF-2 priming to SHED before encapsulation in hydrogels and in vivo subcutaneous implantation. Our results showed that FGF-2 priming is more efficient than hypoxia at increasing SHED-induced vascularization compared with nonprimed controls. Altogether, these data demonstrate that FGF-2 priming enhances the angiogenic potential of SHED through the secretion of both HGF and VEGF. ©AlphaMed Press.

Activation of BAD by therapeutic inhibition of epidermal growth factor receptor and transactivation by insulin-like growth factor receptor.

PubMed

Gilmore, Andrew P; Valentijn, Anthony J; Wang, Pengbo; Ranger, Ann M; Bundred, Nigel; O'Hare, Michael J; Wakeling, Alan; Korsmeyer, Stanley J; Streuli, Charles H

2002-08-02

Novel cancer chemotherapeutics are required to induce apoptosis by activating pro-apoptotic proteins. Both epidermal growth factor (EGF) and insulin-like growth factor (IGF) provide potent survival stimuli in many epithelia, and activation of their receptors is commonly observed in solid human tumors. Here we demonstrate that blockade of the EGF receptor by a new drug in phase III clinical trails for cancer, ZD1839, potently induces apoptosis in mammary epithelial cell lines and primary cultures, as well as in a primary pleural effusion from a breast cancer patient. We identified the mechanism of apoptosis induction by ZD1839. We showed that it prevents cell survival by activating the pro-apoptotic protein BAD. Moreover, we demonstrate that IGF transactivates the EGF receptor and that ZD1839 blocks IGF-mediated phosphorylation of MAPK and BAD. Many cancer therapies kill tumor cells by inducing apoptosis as a consequence of targeting DNA; however, the threshold at which apoptosis can be triggered through DNA damage is often different from that in normal cells. Our results indicate that by targeting a growth factor-mediated survival signaling pathway, BAD phosphorylation can be manipulated therapeutically to induce apoptosis.

Extracellular growth factors and mitogens cooperate to drive mitochondrial biogenesis

PubMed Central

Echave, Pedro; Machado-da-Silva, Gisela; Arkell, Rebecca S.; Duchen, Michael R.; Jacobson, Jake; Mitter, Richard; Lloyd, Alison C.

2009-01-01

Summary Cells generate new organelles when stimulated by extracellular factors to grow and divide; however, little is known about how growth and mitogenic signalling pathways regulate organelle biogenesis. Using mitochondria as a model organelle, we have investigated this problem in primary Schwann cells, for which distinct factors act solely as mitogens (neuregulin) or as promoters of cell growth (insulin-like growth factor 1; IGF1). We find that neuregulin and IGF1 act synergistically to increase mitochondrial biogenesis and mitochondrial DNA replication, resulting in increased mitochondrial density in these cells. Moreover, constitutive oncogenic Ras signalling results in a further increase in mitochondrial density. This synergistic effect is seen at the global transcriptional level, requires both the ERK and phosphoinositide 3-kinase (PI3K) signalling pathways and is mediated by the transcription factor ERRα. Interestingly, the effect is independent of Akt-TOR signalling, a major regulator of cell growth in these cells. This separation of the pathways that drive mitochondrial biogenesis and cell growth provides a mechanism for the modulation of mitochondrial density according to the metabolic requirements of the cell. PMID:19920079

Nerve Growth Factor Expression Is Not Associated with Perineural Invasion in Extrahepatic Cholangiocarcinoma.

PubMed

Urabe, Kazuhide; Murakami, Yoshiaki; Kondo, Naru; Uemura, Kenichiro; Hashimoto, Yasushi; Nakagawa, Naoya; Sasaki, Hayato; Hiyama, Eiso; Takahashi, Shinya; Sueda, Taijiro

2016-03-01

Although the presence of perineural invasion has been recognized as a poor prognostic factor in extrahepatic cholangiocarcinoma, the molecular mechanisms of perineural invasion in extrahepatic cholangiocarcinoma remain unclear. Nerve growth factor has been reported to be a candidate predictive biomarker of perineural invasion in some cancers. To investigate the impact of intratumoral nerve growth factor expression in resected extrahepatic cholangiocarcinoma on survival. Intratumoral nerve growth factor expression was investigated immunohistochemically in 112 patients with resected extrahepatic cholangiocarcinoma. Associations between nerve growth factor expression and clinicopathological factors were statistically evaluated, and risk factors for poor survival were analyzed using univariate and multivariate analyses. High and low nerve growth factor expression was observed in 62 (55%) and 50 (45%) patients, respectively. For all 112 patients, no significant correlation was found between nerve growth factor expression and presence of perineural invasion (P = 0.942). Moreover, nerve growth factor expression was not associated with recurrence-free survival (P = 0.861) and overall survival (P = 0.973). In multivariate analysis, lymph node metastasis (P = 0.004) was identified as an independent risk factor for early recurrence and the presence of perineural invasion (P = 0.002) and lymph node metastasis (P < 0.001) was identified as independent risk factors for poor survival. Intratumoral nerve growth factor expression is not associated with perineural invasion or recurrence-free and overall survival in patients with resected extrahepatic cholangiocarcinoma.

Fibroblast growth factor-2-induced host stroma reaction during initial tumor growth promotes progression of mouse melanoma via vascular endothelial growth factor A-dependent neovascularization.

PubMed

Tsunoda, Satoshi; Nakamura, Toshiyuki; Sakurai, Hiroaki; Saiki, Ikuo

2007-04-01

Fibroblast growth factor (FGF)-2 has been considered to play a critical role in neovascularization in several tumors; however, its precise role in tumor progression is not fully understood. In the present study, we have characterized the role of FGF-2 in B16-BL6 mouse melanoma cells, focusing on effects during the initial phase of tumor growth. FGF-2 was injected at the tumor inoculation site of dorsal skin during the initial phase. FGF-2 induced marked tumor growth and lymph node metastasis. This was well correlated with an increase in neovascularization in the host stroma. FGF-2 also recruited inflammatory and mesenchymal cells in host stroma. Marked tumor growth, pulmonary metastasis and intensive neovascularization in tumor parenchyma were also observed after a single injection of FGF-2 into the footpad inoculation site. In contrast, repeated injections of FGF-2 at a site remote from the footpad tumor were ineffective in promoting tumor growth and metastasis. These promoting activities of FGF-2 were blocked by local injections of a glucocorticoid hormone, suggesting that host inflammatory responses induced by FGF-2 are associated with FGF-2-induced tumor progression. In addition, although FGF-2 did not promote cellular proliferation and vascular endothelial growth factor A (VEGFA) mRNA expression in B16-BL6 cells in vitro, FGF-2 induced VEGFA expression in host stroma rather than tumor tissue, and local injections of a neutralizing antibody against VEGFA inhibited these activities of FGF-2 in vivo. These results indicate that abundant FGF-2 during the initial phase of tumor growth induces VEGFA-dependent intensive neovascularization in host stroma, and supports marked tumor growth and metastasis.

Sequential growth factor application in bone marrow stromal cell ligament engineering.

PubMed

Moreau, Jodie E; Chen, Jingsong; Horan, Rebecca L; Kaplan, David L; Altman, Gregory H

2005-01-01

In vitro bone marrow stromal cell (BMSC) growth may be enhanced through culture medium supplementation, mimicking the biochemical environment in which cells optimally proliferate and differentiate. We hypothesize that the sequential administration of growth factors to first proliferate and then differentiate BMSCs cultured on silk fiber matrices will support the enhanced development of ligament tissue in vitro. Confluent second passage (P2) BMSCs obtained from purified bone marrow aspirates were seeded on RGD-modified silk matrices. Seeded matrices were divided into three groups for 5 days of static culture, with medium supplement of basic fibroblast growth factor (B) (1 ng/mL), epidermal growth factor (E; 1 ng/mL), or growth factor-free control (C). After day 5, medium supplementation was changed to transforming growth factor-beta1 (T; 5 ng/mL) or C for an additional 9 days of culture. Real-time RT-PCR, SEM, MTT, histology, and ELISA for collagen type I of all sample groups were performed. Results indicated that BT supported the greatest cell ingrowth after 14 days of culture in addition to the greatest cumulative collagen type I expression measured by ELISA. Sequential growth factor application promoted significant increases in collagen type I transcript expression from day 5 of culture to day 14, for five of six groups tested. All T-supplemented samples surpassed their respective control samples in both cell ingrowth and collagen deposition. All samples supported spindle-shaped, fibroblast cell morphology, aligning with the direction of silk fibers. These findings indicate significant in vitro ligament development after only 14 days of culture when using a sequential growth factor approach.

Mechanisms of Hepatocyte Growth Factor Activation in Cancer Tissues

PubMed Central

Kawaguchi, Makiko; Kataoka, Hiroaki

2014-01-01

Hepatocyte growth factor/scatter factor (HGF/SF) plays critical roles in cancer progression through its specific receptor, MET. HGF/SF is usually synthesized and secreted as an inactive proform (pro-HGF/SF) by stromal cells, such as fibroblasts. Several serine proteases are reported to convert pro-HGF/SF to mature HGF/SF and among these, HGF activator (HGFA) and matriptase are the most potent activators. Increased activities of both proteases have been observed in various cancers. HGFA is synthesized mainly by the liver and secreted as an inactive pro-form. In cancer tissues, pro-HGFA is likely activated by thrombin and/or human kallikrein 1-related peptidase (KLK)-4 and KLK-5. Matriptase is a type II transmembrane serine protease that is expressed by most epithelial cells and is also synthesized as an inactive zymogen. Matriptase activation is likely to be mediated by autoactivation or by other trypsin-like proteases. Recent studies revealed that matriptase autoactivation is promoted by an acidic environment. Given the mildly acidic extracellular environment of solid tumors, matriptase activation may, thus, be accelerated in the tumor microenvironment. HGFA and matriptase activities are regulated by HGFA inhibitor (HAI)-1 (HAI-1) and/or HAI-2 in the pericellular microenvironment. HAIs may have an important role in cancer cell biology by regulating HGF/SF-activating proteases. PMID:25268161

The serum levels of connective tissue growth factor in patients with systemic lupus erythematosus and lupus nephritis.

PubMed

Wang, F-M; Yu, F; Tan, Y; Liu, G; Zhao, M-H

2014-06-01

The expression of connective tissue growth factor mRNA in human kidneys may serve as an early marker for lupus nephritis progression. Therefore, we speculated that connective tissue growth factor may be involved in the pathogenesis of systemic lupus erythematosus and lupus nephritis. In this study, we set out to investigate the associations between serum connective tissue growth factor levels and clinicopathological features of patients with systemic lupus erythematosus and lupus nephritis. Serum samples from patients with non-renal systemic lupus erythematosus, renal biopsy-proven lupus nephritis and healthy control subjects were detected by enzyme-linked immunosorbent assay for serum connective tissue growth factor levels. The associations between connective tissue growth factor levels and clinicopathological features of the patients were further analysed. The levels of serum connective tissue growth factor in patients with non-renal systemic lupus erythematosus and lupus nephritis were both significantly higher than those in the normal control group (34.14 ± 12.17 ng/ml vs. 22.8 ± 3.0 ng/ml, p<0.001; 44.1 ± 46.8 ng/ml vs. 22.8 ± 3.0 ng/ml, p = 0.035, respectively). There was no significant difference of the serum connective tissue growth factor levels between non-renal systemic lupus erythematosus and lupus nephritis group (34.14 ± 12.17 ng/ml vs. 44.1 ± 46.8 ng/ml, p = 0.183). Serum connective tissue growth factor levels were significantly higher in lupus nephritis patients with the following clinical manifestations, including anaemia (51.3 ± 51.4 ng/ml vs. 23.4 ± 9.7 ng/ml, p<0.001) and acute renal failure (85.5 ± 75.0 ng/ml vs. 31.2 ± 21.8 ng/ml, p = 0.002). Serum connective tissue growth factor levels in class IV were significantly higher than that in class II, III and V (57.6 ± 57.5 ng/ml vs. 18.7 ± 6.4 ng/ml, p = 0.019; 57.6 ± 57.5 ng/ml vs. 25.2�

Metabolic effects of growth factors and polycyclic aromatic hydrocarbons on cultured human placental cells of early and late gestation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guyda, H.J.

1991-03-01

The metabolic effects of epidermal growth factor (EGF), insulin, insulin-like growth factor-I (IGF-I), and IGF-II were determined on human placental cells in monolayer culture obtained from early gestation (less than 20 weeks) and late gestation (38-42 weeks). Parameters studied were uptake of aminoisobutyric acid (AIB), uptake of 3-O-methylglucose and (3H)thymidine incorporation into cell protein. Since benzo(alpha)pyrene (BP) inhibits EGF binding and autophosphorylation in cultured human placental cells, particularly in early gestation, we also studied the effect of benzo(alpha)pyrene and other polycyclic aromatic hydrocarbons (PAHs) on EGF-mediated AIB uptake. The metabolic effects of EGF, insulin, and the IGFs in cultured humanmore » placental cells varied with gestational age and the growth factor studied. All three classes of growth factors stimulated AIB uptake in both early and late gestation at concentrations from 10-100 micrograms/L, well within a physiological range. However, insulin stimulation of AIB uptake was maximal at a high concentration in both early and late gestation cells, suggesting an action via type 1 IGF receptors rather than via insulin receptors. EGF stimulated 3-O-methylglucose uptake only in term placental cells. No significant stimulation of (3H)thymidine incorporation by any of the growth factors tested was seen with either early or late gestation cells. The effect of PAHs on AIB uptake by cultured placental cells was variable. BP alone stimulated AIB uptake by both very early and late gestation cells and enhanced EGF-stimulated AIB uptake. alpha-naphthoflavone alone inhibited AIB uptake at all gestational ages and inhibited EGF-stimulated AIB uptake. beta-Naphthoflavone and 3-methylcholanthrene minimally inhibited AIB uptake by early gestation cells and did not modify EGF-stimulated uptake at any gestational period.« less

Immunoassays for the measurement of IGF-II, IGFBP-2 and -3, and ICTP as indirect biomarkers of recombinant human growth hormone misuse in sport. Values in selected population of athletes.

PubMed

Abellan, Rosario; Ventura, Rosa; Palmi, Ilaria; di Carlo, Simonetta; Bacosi, Antonella; Bellver, Montse; Olive, Ramon; Pascual, Jose Antonio; Pacifici, Roberta; Segura, Jordi; Zuccaro, Piergiorgio; Pichini, Simona

2008-11-04

Insulin-like growth factor-II (IGF-II), insulin-like growth factor binding proteins (IGFBPs) -2 and -3 and C-terminal telopeptide of type I collagen (ICTP) have been proposed, among others, as indirect biomarkers of the recombinant human growth hormone misuse in sport. An extended intra- and inter-laboratory validation of commercially available immunoassays for biomarkers detection was performed. ELISA assays for total IGF-II, IGFBP-2 and IGFBP-3 (IGF-II/ELISA1: DSLabs, IGFBP-2/ELISA2: Biosource, and IGFBP-3/ELISA3: BioSource) and an EIA assay for ICTP (ICTP/EIA: Orion Diagnostica) were evaluated. The inter- and intra-laboratory precision values were acceptable for all evaluated assays (maximum imprecision of 30% and 66% were found only for the lowest quality control samples of IGF-II and IGFBP-3). Correct accuracy was obtained for all inter-laboratory immunoassays and for IGFBP-2 intra-laboratory immunoassay. The range of concentrations found in serum samples under investigation was always covered by the calibration curves of the studied immunoassays. However, 11% and 15% of the samples felt below the estimated LOQ for IGF-II and ICTP, respectively, in the zone where lower precision was obtained. Although the majority of evaluated assays showed an overall reliability not always suitable for antidoping control analysis, relatively high concordances between laboratory results were obtained for all assays. Evaluated immunoassays were used to measure serum concentrations of IGF-II, IGFBP-2 and -3 and ICTP in elite athletes of various sport disciplines at different moments of the training season; in recreational athletes at baseline conditions and finally in sedentary individuals. Serum IGF-II was statistically higher both in recreational and elite athletes compared to sedentary individuals. Elite athletes showed lower IGFBP-2 and higher IGFBP-3 concentration with respect to recreational athletes and sedentary people. Among elite athletes, serum IGFBP-3 (synchronized

Transcription factor EGR-1 suppresses the growth and transformation of human HT-1080 fibrosarcoma cells by induction of transforming growth factor beta 1.

PubMed Central

Liu, C; Adamson, E; Mercola, D

1996-01-01

The early growth response 1 (EGR-1) gene product is a transcription factor with role in differentiation and growth. We have previously shown that expression of exogenous EGR-1 in various human tumor cells unexpectedly and markedly reduces growth and tumorigenicity and, conversely, that suppression of endogenous Egr-1 expression by antisense RNA eliminates protein expression, enhances growth, and promotes phenotypic transformation. However, the mechanism of these effects remained unknown. The promoter of human transforming growth factor beta 1 (TGF-beta 1) contains two GC-rich EGR-1 binding sites. We show that expression of EGR-1 in human HT-1080 fibrosarcoma cells uses increased secretion of biologically active TGF-beta 1 in direct proportion (rPearson = 0.96) to the amount of EGR-1 expressed and addition of recombinant human TGF-beta 1 is strongly growth-suppressive for these cells. Addition of monoclonal anti-TGF-beta 1 antibodies to EGR-1-expressing HT-1080 cells completely reverses the growth inhibitory effects of EGR-1. Reporter constructs bearing the EGR-1 binding segment of the TGF-beta 1 promoter was activated 4- to 6-fold relative to a control reporter in either HT-1080 cells that stably expressed or parental cells cotransfected with an EGR-1 expression vector. Expression of delta EGR-1, a mutant that cannot interact with the corepressors, nerve growth factor-activated factor binding proteins NAB1 and NAB2, due to deletion of the repressor domain, exhibited enhanced transactivation of 2- to 3.5-fold over that of wild-type EGR-1 showing that the reporter construct reflected the appropriate in vivo regulatory context. The EGR-1-stimulated transactivation was inhibited by expression of the Wilms tumor suppressor, a known specific DNA-binding competitor. These results indicate that EGR-1 suppresses growth of human HT-1080 fibrosarcoma cells by induction of TGF-beta 1. Images Fig. 1 Fig. 5 PMID:8876223

Quantification of growth factor signaling and pathway cross talk by live-cell imaging

PubMed Central

Gross, Sean M.

2017-01-01

Peptide growth factors stimulate cellular responses through activation of their transmembrane receptors. Multiple intracellular signaling cascades are engaged following growth factor–receptor binding, leading to short- and long-term biological effects. Each receptor-activated signaling pathway does not act in isolation but rather interacts at different levels with other pathways to shape signaling networks that are distinctive for each growth factor. To gain insights into the specifics of growth factor-regulated interactions among different signaling cascades, we developed a HeLa cell line stably expressing fluorescent live-cell imaging reporters that are readouts for two major growth factor-stimulated pathways, Ras–Raf–Mek–ERK and phosphatidylinositol (PI) 3-kinase–Akt. Incubation of cells with epidermal growth factor (EGF) resulted in rapid, robust, and sustained ERK signaling but shorter-term activation of Akt. In contrast, hepatocyte growth factor induced sustained Akt signaling but weak and short-lived ERK activity, and insulin-like growth factor-I stimulated strong long-term Akt responses but negligible ERK signaling. To address potential interactions between signaling pathways, we employed specific small-molecule inhibitors. In cells incubated with EGF or platelet-derived growth factor-AA, Raf activation and the subsequent stimulation of ERK reduced Akt signaling, whereas Mek inhibition, which blocked ERK activation, enhanced Akt and turned transient effects into sustained responses. Our results reveal that individual growth factors initiate signaling cascades that vary markedly in strength and duration and demonstrate in living cells the dramatic effects of cross talk from Raf and Mek to PI 3-kinase and Akt. Our data further indicate how specific growth factors can encode distinct cellular behaviors by promoting complex interactions among signaling pathways. PMID:28100485

Effects of Growth Factors on Dental Stem/ProgenitorCells

PubMed Central

Kim, Sahng G.; Solomon, Charles; Zheng, Ying; Suzuki, Takahiro; Mo, Chen; Song, Songhee; Jiang, Nan; Cho, Shoko; Zhou, Jian; Mao, Jeremy J.

2014-01-01

Synopsis The primary goal of regenerative endodontics is to restore the vitality and functions of the dentin-pulp complex, as opposed to filing of the root canal with bioinert materials. Structural restoration is also important but is likely secondary to vitality and functions. Myriads growth factors regulate multiple cellular functions including migration, proliferation, differentiation and apoptosis of several cell types that are intimately involved in dentin-pulp regeneration: odontoblasts, interstitial fibroblasts, vascular-endothelial cells and sprouting nerve fibers. Recent work showing that growth factor delivery, without cell transplantation, can yield pulp-dentin like tissues in vivo provides one of the tangible pathways for regenerative endodontics. This review synthesizes our knowledge on a multitude of growth factors that are known or anticipated to be efficacious in dental pulp-dentin regeneration. PMID:22835538

Neuronal expression of fibroblast growth factor receptors in zebrafish.

PubMed

Rohs, Patricia; Ebert, Alicia M; Zuba, Ania; McFarlane, Sarah

2013-12-01

Fibroblast growth factor (FGF) signaling is important for a host of developmental processes such as proliferation, differentiation, tissue patterning, and morphogenesis. In vertebrates, FGFs signal through a family of four fibroblast growth factor receptors (FGFR 1-4), one of which is duplicated in zebrafish (FGFR1). Here we report the mRNA expression of the five known zebrafish fibroblast growth factor receptors at five developmental time points (24, 36, 48, 60, and 72h postfertilization), focusing on expression within the central nervous system. We show that the receptors have distinct and dynamic expression in the developing zebrafish brain, eye, inner ear, lateral line, and pharynx. In many cases, the expression patterns are similar to those of homologous FGFRs in mouse, chicken, amphibians, and other teleosts. Copyright © 2013 Elsevier B.V. All rights reserved.

Molecular targets for the therapy of cancer associated with metabolic syndrome (transcription and growth factors).

PubMed

Yunusova, Natalia V; Kondakova, Irina V; Kolomiets, Larisa A; Afanas'ev, Sergey G; Chernyshova, Alena L; Kudryavtsev, Igor V; Tsydenova, Anastasia A

2018-06-01

Metabolic syndrome (MS) is one of the leading risk factors for the development of cardiovascular diseases, type II diabetes mellitus and reproductive system diseases. Currently, not only cardiovascular disease and reproductive history risks related with MS are frequently discussed, but it has been also shown that MS is associated with increased risk of some common cancers (endometrial cancer, postmenopausal breast cancer, colorectal cancer, biliary tract cancers and liver cancer for men). Further studies are required to understand the mechanisms of the involvement of MS components in the pathogenesis of malignant neoplasms. Changes in the expression of transcription and growth factors in the peripheral tissues as well as in cancer tissues of patients with MS were revealed. Transcription factors (AMP-activated protein kinase-1, STAT3, sterol regulatory element-binding protein-1 and peroxisome proliferator-activated receptor-γ), leptin and adiponectin receptors seem to be the most promising molecular targets for the therapy of cancers associated with MS. © 2017 John Wiley & Sons Australia, Ltd.

Quantification of growth factor signaling and pathway cross talk by live-cell imaging.

PubMed

Gross, Sean M; Rotwein, Peter

2017-03-01

Peptide growth factors stimulate cellular responses through activation of their transmembrane receptors. Multiple intracellular signaling cascades are engaged following growth factor-receptor binding, leading to short- and long-term biological effects. Each receptor-activated signaling pathway does not act in isolation but rather interacts at different levels with other pathways to shape signaling networks that are distinctive for each growth factor. To gain insights into the specifics of growth factor-regulated interactions among different signaling cascades, we developed a HeLa cell line stably expressing fluorescent live-cell imaging reporters that are readouts for two major growth factor-stimulated pathways, Ras-Raf-Mek-ERK and phosphatidylinositol (PI) 3-kinase-Akt. Incubation of cells with epidermal growth factor (EGF) resulted in rapid, robust, and sustained ERK signaling but shorter-term activation of Akt. In contrast, hepatocyte growth factor induced sustained Akt signaling but weak and short-lived ERK activity, and insulin-like growth factor-I stimulated strong long-term Akt responses but negligible ERK signaling. To address potential interactions between signaling pathways, we employed specific small-molecule inhibitors. In cells incubated with EGF or platelet-derived growth factor-AA, Raf activation and the subsequent stimulation of ERK reduced Akt signaling, whereas Mek inhibition, which blocked ERK activation, enhanced Akt and turned transient effects into sustained responses. Our results reveal that individual growth factors initiate signaling cascades that vary markedly in strength and duration and demonstrate in living cells the dramatic effects of cross talk from Raf and Mek to PI 3-kinase and Akt. Our data further indicate how specific growth factors can encode distinct cellular behaviors by promoting complex interactions among signaling pathways. Copyright © 2017 the American Physiological Society.

Increased Serum Levels of Epidermal Growth Factor in Children with Autism

ERIC Educational Resources Information Center

Iseri, Elvan; Guney, Esra; Ceylan, Mehmet F.; Yucel, Aysegul; Aral, Arzu; Bodur, Sahin; Sener, Sahnur

2011-01-01

The etiology of autism is unclear, however autism is considered as a multifactorial disorder that is influenced by neurological, environmental, immunological and genetic factors. Growth factors, including epidermal growth factor (EGF), play an important role in the celluler proliferation and the differentiation of the central and peripheral…

Differential effects of caffeine on hair shaft elongation, matrix and outer root sheath keratinocyte proliferation, and transforming growth factor-β2/insulin-like growth factor-1-mediated regulation of the hair cycle in male and female human hair follicles in vitro.

PubMed

Fischer, T W; Herczeg-Lisztes, E; Funk, W; Zillikens, D; Bíró, T; Paus, R

2014-11-01

Caffeine reportedly counteracts the suppression of hair shaft production by testosterone in organ-cultured male human hair follicles (HFs). We aimed to investigate the impact of caffeine (i) on additional key hair growth parameters, (ii) on major hair growth regulatory factors and (iii) on male vs. female HFs in the presence of testosterone. Microdissected male and female human scalp HFs were treated in serum-free organ culture for 120 h with testosterone alone (0·5 μg mL(-1)) or in combination with caffeine (0·005-0·0005%). The following effects on hair shaft elongation were evaluated by quantitative (immuno)histomorphometry: HF cycling (anagen-catagen transition); hair matrix keratinocyte proliferation; expression of a key catagen inducer, transforming growth factor (TGF)-β2; and expression of the anagen-prolonging insulin-like growth factor (IGF)-1. Caffeine effects were further investigated in human outer root sheath keratinocytes (ORSKs). Caffeine enhanced hair shaft elongation, prolonged anagen duration and stimulated hair matrix keratinocyte proliferation. Female HFs showed higher sensitivity to caffeine than male HFs. Caffeine counteracted testosterone-enhanced TGF-β2 protein expression in male HFs. In female HFs, testosterone failed to induce TGF-β2 expression, while caffeine reduced it. In male and female HFs, caffeine enhanced IGF-1 protein expression. In ORSKs, caffeine stimulated cell proliferation, inhibited apoptosis/necrosis, and upregulated IGF-1 gene expression and protein secretion, while TGF-β2 protein secretion was downregulated. This study reveals new growth-promoting effects of caffeine on human hair follicles in subjects of both sexes at different levels (molecular, cellular and organ). © 2014 British Association of Dermatologists.

Growth factors in the anterior segment: role in tissue maintenance, wound healing and ocular pathology.

PubMed

Klenkler, Bettina; Sheardown, Heather

2004-11-01

A number of growth factors and their associated receptors, including epidermal growth factor, transforming growth factor-beta, keratinocyte growth factor, hepatocyte growth factor, fibroblast growth factor and platelet-derived growth factor have been detected in the anterior segment of the eye. On binding to cellular receptors, these factors activate signalling cascades, which regulate functions including mitosis, differentiation, motility and apoptosis. Production of growth factors by corneal cells and their presence in the tear fluid and aqueous humour is essential for maintenance and renewal of normal tissue in the anterior eye and the prevention of undesirable immune or angiogenic reactions. Growth factors also play a vital role in corneal wound healing, mediating the proliferation of epithelial and stromal tissue and affecting the remodelling of the extracellular matrix (ECM). These functions depend on a complex interplay between growth factors of different types, the ECM, and regulatory mechanisms of the affected cells. Imbalances may lead to deficient wound healing and various ocular pathologies, including edema, neovascularization and glaucoma. Growth factors may be targeted in therapeutic ophthalmic applications, through exogenous application or selective inhibition, and may be used to elicit specific cellular responses to ophthalmic materials. A thorough understanding of the mechanism and function of growth factors and their actions in the complex environment of the anterior eye is required for these purposes. Growth factors, their function and mechanisms of action as well as the interplay between different growth factors based on recent in vitro and in vivo studies are presented.

Epidermal growth factor increases cortisol production and type II 3 beta-hydroxysteroid dehydrogenase/Delta(5)-Delta(4)-isomerase expression in human adrenocortical carcinoma cells: evidence for a Stat5-dependent mechanism.

PubMed

Feltus, F Alex; Kovacs, William J; Nicholson, Wendell; Silva, Corrine M; Nagdas, Subir K; Ducharme, Nicole A; Melner, Michael H

2003-05-01

We tested the ability of epidermal growth factor (EGF) to regulate a key enzyme in the adrenal synthesis of glucocorticoids: human type II 3beta-hydroxysteroid dehydrogenase/Delta(5)-Delta(4)-isomerase (3 beta HSD). EGF treatment (25 ng/ml) of human adrenocortical carcinoma cells (H295R) resulted in a 5-fold increase in cortisol production and a corresponding 2-fold increase in 3 beta HSD mRNA. Experiments were performed to determine whether EGF is acting through a previously identified signal transducer and activator of transcription 5 (Stat5)-responsive element located from -110 to -118 in the human type II 3 beta HSD promoter. A Stat5 expression construct was cotransfected with a 3 beta HSD-chloramphenol acetyltransferase (CAT) reporter construct comprised of nucleotides -301-->+45 of the human type II 3 beta HSD promoter linked to the CAT reporter gene sequence. The addition of EGF at doses as low as 10 ng/ml resulted in an 11- to 15-fold increase in CAT activity. The introduction of 3-bp point mutations into critical nucleotides in the Stat5 response element obviated the EGF response. Either Stat5a or Stat5b isoforms induced CAT reporter expression upon treatment with EGF. These results demonstrate the ability of EGF to regulate the expression of a critical enzyme (3 beta HSD) in the production of cortisol and suggest a molecular mechanism by which this regulation occurs.

Colocalization of insulin-like growth factor-binding protein with insulin-like growth factor I.

PubMed

Kobayashi, S; Clemmons, D R; Venkatachalam, M A

1991-07-01

We report the localization of insulin-like growth factor I (IGF-I) and a 25-kDa form of insulin-like growth factor-binding protein (IGF-BP-1) in adult rat kidney. The antigens were localized using a rabbit anti-human IGF-I antibody, and a rabbit anti-human IGF-BP-1 antibody raised against human 25-kDa IGF-BP-1 purified from amniotic fluid. Immunohistochemistry by the avidin-biotin peroxidase conjugate technique showed that both peptides are located in the same nephron segments, in the same cell types. The most intense staining was in papillary collecting ducts. There was moderate staining also in cortical collecting ducts and medullary thick ascending limbs of Henle's loop. In collecting ducts the antigens were shown to be present in principal cells but not in intercalated cells. In distal convoluted tubules, cortical thick ascending limbs, and in structures presumptively identified as thin limbs of Henle's loops there was only modest staining. The macula densa, however, lacked immunoreactivity. Colocalization of IGF-I and IGF-BP-1 in the same cells supports the notion, derived from studies on cultured cells, that the actions of IGF-I may be modified by IGF-BPs that are present in the same location.

Postnatal Deletion of the Type II Transforming Growth Factor-β Receptor in Smooth Muscle Cells Causes Severe Aortopathy in Mice.