scholarly journals Expression patterns and different subcellular localization of the growth factors HDGF (hepatoma-derived growth factor) and HRP-3 (HDGF-related protein-3) suggest functions in addition to their mitogenic activity

2004 ◽  
Vol 378 (1) ◽  
pp. 169-176 ◽  
Author(s):  
Mekky M. ABOUZIED ◽  
Stephan L. BAADER ◽  
Frank DIETZ ◽  
Joachim KAPPLER ◽  
Volkmar GIESELMANN ◽  
...  
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Subcellular Localization ◽  
Single Cells ◽  
Expression Patterns ◽  
Primary Cultures ◽  
Brain Slices ◽  
Adult Brain ◽  
Differentiated Cells ◽  
C Terminus

HDGF (hepatoma-derived growth factor) and the HRPs (HDGF-related proteins) comprise a family of six proteins which display high identity in their N-terminus, but differ at the C-terminus. Here we investigate the patterns of expression of HDGF and HRP-3, by generating antisera specifically recognizing each growth factor. Whereas HRP-3 protein is expressed only in brain, HDGF can be found in a broad range of tissues, with highest levels in brain, testis, lung and spleen. The expression of HDGF and HRP-3 was found to be regulated during brain development, with highest levels around birth, followed by a decline until postnatal day 9. Interestingly, expression of HRP-3 increases again in adult brain. In situ hybridization and immunohistochemistry of cerebellar, cerebral and hippocampal brain slices showed that expression of both growth factors is not limited to areas of high proliferative activity. Both mRNAs and proteins are expressed in neuronal as well as glial cells. Immunocytochemistry of cultured neocortical neurons revealed that HDGF and HRP-3 can be found in the nucleus as well as the cytoplasm. HDGF is restricted to the neuronal soma, whereas HRP-3 can also be found in neurites. Thus the expression of HDGF and HRP-3 in differentiated cells, post-mitotic neurons and primary cultures of rat neocortex points to functions in brain that might not be limited to proliferation. In addition, their simultaneous expression in the same cell and their different subcellular localization in cultured neurons suggest different functions of HDGF and HRP-3 within single cells.

Mechanisms of renal tubular cell hypertrophy: mitogen-induced suppression of proteolysis

1997 ◽  
Vol 273 (3) ◽  
pp. C843-C851 ◽  
Author(s):  
H. A. Franch ◽  
P. V. Curtis ◽  
W. E. Mitch
Keyword(s):  
Protein Synthesis ◽  
Growth Factors ◽  
Growth Factor ◽  
Protein Degradation ◽  
Transforming Growth Factor ◽  
Primary Cultures ◽  
Renal Tubular Cell ◽  
Kidney Cells ◽  
Tgf Beta ◽  
Lysosomal Proteolysis

The combination of epidermal growth factor (EGF) plus transforming growth factor-beta 1 (TGF-beta 1) causes hypertrophy in renal epithelial cells. One mechanism contributing to hypertrophy is that EGF induces activation of the cell cycle and increases protein synthesis, whereas TGF-beta 1 prevents cell division, thereby converting hyperplasia to hypertrophy. To assess whether suppression of proteolysis is another mechanism causing hypertrophy induced by these growth factors, we measured protein degradation in primary cultures of proximal tubule cells and in cultured NRK-52E kidney cells. A concentration of 10(-8) M EGF alone or EGF plus 10(-10) M TGF-beta 1 decreased proteolysis by approximately 30%. TGF-beta 1 alone did not change protein degradation. Using inhibitors, we examined which proteolytic pathway is suppressed. Neither proteasome nor calpain inhibitors prevented the antiproteolytic response to EGF + TGF-beta 1. Inhibitors of lysosomal proteases eliminated the antiproteolytic response to EGF + TGF-beta 1, suggesting that these growth factors act to suppress lysosomal proteolysis. This antiproteolytic response was not caused by impaired EGF receptor signaling, since lysosomal inhibitors did not block EGF-induced protein synthesis. We conclude that suppression of lysosomal proteolysis contributes to growth factor-mediated hypertrophy of cultured kidney cells.

174 EPIDERMAL GROWTH FACTORS AND CALBINDIN-D9k GENE EXPRESSIONS DURING PREGANCY IN THE PORCINE UTERUS

2008 ◽  
Vol 20 (1) ◽  
pp. 167
Author(s):  
Y.-J. Kim ◽  
E.-M. Jung ◽  
G.-S. Lee ◽  
S.-H. Hyun ◽  
E.-B. Jeung
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Transforming Growth Factor ◽  
Expression Patterns ◽  
Negative Control ◽  
Heparin Binding ◽  
Gene Expressions ◽  
Calbindin D9k ◽  
Genes Encoding ◽  
Epidermal Growth

To stably maintain pregnancy, several genes are expressed in the uterus. In particular, the endometrial expression of genes encoding growth factors appears to play a key role in maternal–fetal communication. Previous studies have characterized the endometrial expression kinetics of the genes encoding epidermal growth factor (EGF), its receptor (EGFR), transforming growth factor-alpha (TGF-α), amphiregulin (Areg), heparin-binding (Hb) EGF, and calbindin-D9k (CaBP-9k) in the pig during implantation. Here, we further characterized the expression patterns of these molecules during the entire porcine pregnancy. Porcine (n = 3 per PD) were collected at pregnancy days (PD) 12, 15, 30, 60, 90, and 110 and subjected to semi-quantitative RT-PCR. The data were analyzed with a nonparametric one-way analysis of variance using the Kruskal-Wallis test, followed by Dunnett's test for multiple comparisons to the negative control. EGF and EGFR showed similar expression patterns, being highly expressed around implantation time and then disappearing. TGF-α and Areg expression levels rose steadily until they peaked at PD30, after which they gradually decreased to PD12 levels. The Areg mRNA expression pattern was confirmed by real-time PCR, and similar Areg protein expression patterns were observed. Immunohistochemical analysis of PD60 uteri revealed Areg in the glandular and luminal epithelial cells. Hb-EGF was steadily expressed throughout the entire pregnancy while CaBP-9k was expressed strongly on PD12, and then declined sharply in PD15 before recovering slightly for the remainder of the pregnancy. Thus, the EGF family may play a key role during implantation in pigs. In addition, CaBP-9k may help maintain uterine quiescence during pregnancy by sequestering cytoplasmic Ca2+.

Keratinocyte growth factor increases mRNAs for SP-A and SP-B in adult rat alveolar type II cells in culture

1995 ◽  
Vol 269 (3) ◽  
pp. L344-L350 ◽  
Author(s):  
K. Sugahara ◽  
J. S. Rubin ◽  
R. J. Mason ◽  
E. L. Aronsen ◽  
J. M. Shannon
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Keratinocyte Growth Factor ◽  
Primary Cultures ◽  
Surfactant Proteins ◽  
Alveolar Type ◽  
Type Ii Cells ◽  
Type Ii ◽  
Alveolar Type Ii Cells ◽  
Adult Rat

The production of pulmonary surfactant, a complex of phospholipids and lung-specific surfactant proteins, is a primary function of alveolar type II cells. Although previous studies have demonstrated a role for cell-extracellular matrix interactions and normal cell shape in the maintenance of differentiated function in primary cultures of adult rat type II cells, a positive role for growth factors in surfactant protein gene expression in isolated normal adult type II cells has not been reported. In the present study, we have examined the effects of a panel of hormones, growth factors, and cytokines on the expression of mRNAs for surfactant proteins A, B, and C (SP-A, SP-B, and SP-C). Our results show that keratinocyte growth factor (KGF) induced a two- to threefold increase in steady-state levels of mRNAs for SP-A and SP-B, but had no effect on or decreased SP-C mRNA. The increase in SP-A mRNA was accompanied by an increase in SP-A protein. The effects of KGF were both dose and time dependent, and they could be neutralized by a monoclonal antibody against KGF. The effects of KGF were mimicked by acidic fibroblast growth factor, which will bind the KGF receptor. We conclude that KGF can support differentiation of alveolar type II cells as well as act as a mitogen, thus suggesting an important role for KGF in maintenance of the alveolar epithelium.

scholarly journals Effects of growth factors on hormonal stimulation of amino acid transport in primary cultures of rat hepatocytes

1983 ◽  
Vol 210 (2) ◽  
pp. 361-366 ◽  
Author(s):  
P Auberger ◽  
M Samson ◽  
A Le Cam
Keyword(s):  
Growth Factors ◽  
Amino Acid ◽  
Growth Factor ◽  
Cyclic Amp ◽  
Primary Cultures ◽  
Rat Hepatocytes ◽  
Acid Transport ◽  
Hormonal Stimulation ◽  
Hormonal Effect ◽  
Stimulation Of

In primary cultures of rat hepatocytes, epidermal growth factor (EGF), platelet-derived growth factor (PDGF) and foetal-calf serum (FCS) prevented the stimulation of amino acid transport by glucagon (cyclic AMP-dependent) and by catecholamines (cyclic AMP-independent), but not by insulin. The insulin effect, as well as the effect of other hormones, were totally inhibited by thrombin through a mechanism independent of its proteolytic activity. The inhibitory effect of growth factors, not found in freshly isolated hepatocytes, was expressed very early in culture (4h). Induction of tyrosine aminotransferase by glucagon or dexamethasone, which, like stimulation of transport, represents a late hormonal effect, was not affected by EGF, PDGF or FCS, but was inhibited by thrombin. In contrast, none of the rapid changes in protein phosphorylation caused by hormones was altered by growth factors. Thus the inhibition by growth factors of hormonal stimulation of transport presumably involves late step(s) in the cascade of events implicated in this hormonal effect.

Role of superoxide in apoptosis induced by growth factor withdrawal

1998 ◽  
Vol 275 (5) ◽  
pp. F691-F702 ◽  
Author(s):  
Wilfred Lieberthal ◽  
Veronica Triaca ◽  
Jason S. Koh ◽  
Patrick J. Pagano ◽  
Jerrold S. Levine
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Oxidant Stress ◽  
Primary Cultures ◽  
High Dose ◽  
Caspase Activity ◽  
Apoptotic Pathway ◽  
Signaling Mechanism ◽  
Growth Factor Deprivation

We have examined the role of reactive oxygen species (ROS) in apoptosis induced by growth factor deprivation in primary cultures of mouse proximal tubular (MPT) cells. When confluent monolayers of MPT cells are deprived of all growth factors, the cells die by apoptosis over a 10- and 14-day period. Both epidermal growth factor (EGF) and high-dose insulin directly inhibit apoptosis of MPT cells deprived of growth factors. Growth factor deprivation results in an increase in the cellular levels of superoxide anion while apoptosis of MPT cells induced by growth factor withdrawal is inhibited by a number of antioxidants and scavengers of ROS. Growth factor deprivation also results in activation of caspase activity, which is inhibited by EGF and high-dose insulin as well as by the ROS scavengers and antioxidants that inhibit apoptosis. The cell-permeant caspase inhibitor, z-Val-Ala-Asp-CH2F (zVAD-fmk), prevents the increase in caspase activity and markedly inhibits apoptosis induced by growth factor deprivation. However, zVAD-fmk had no effect on the increased levels of superoxide associated with growth factor deprivation. Thus we provide novel evidence that ROS play an important role in mediating apoptosis associated with growth factor deprivation. ROS appear to act upstream of caspases in the apoptotic pathway. We hypothesize that oxidant stress, induced by growth factor withdrawal, represents a signaling mechanism for the default pathway of apoptosis.

scholarly journals Adult hippocampal neural stem and progenitor cells regulate the neurogenic niche by secreting VEGF

2015 ◽  
Vol 112 (13) ◽  
pp. 4128-4133 ◽  
Author(s):  
Elizabeth D. Kirby ◽  
Akela A. Kuwahara ◽  
Reanna L. Messer ◽  
Tony Wyss-Coray
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Progenitor Cells ◽  
Adult Brain ◽  
Secretory Cells ◽  
Neurogenic Niche ◽  
Stem And Progenitor Cells ◽  
Essential Growth ◽  
Essential Growth Factor

The adult hippocampus hosts a population of neural stem and progenitor cells (NSPCs) that proliferates throughout the mammalian life span. To date, the new neurons derived from NSPCs have been the primary measure of their functional relevance. However, recent studies show that undifferentiated cells may shape their environment through secreted growth factors. Whether endogenous adult NSPCs secrete functionally relevant growth factors remains unclear. We show that adult hippocampal NSPCs secrete surprisingly large quantities of the essential growth factor VEGF in vitro and in vivo. This self-derived VEGF is functionally relevant for maintaining the neurogenic niche as inducible, NSPC-specific loss of VEGF results in impaired stem cell maintenance despite the presence of VEGF produced from other niche cell types. These findings reveal adult hippocampal NSPCs as an unanticipated source of an essential growth factor and imply an exciting functional role for adult brain NSPCs as secretory cells.

scholarly journals Role of the Different Mitogen-Activated Protein Kinase Subfamilies in the Stimulation of Dog and Human Thyroid Epithelial Cell Proliferation by Cyclic Adenosine 5′-Monophosphate and Growth Factors

Endocrinology ◽  
2003 ◽  
Vol 144 (4) ◽  
pp. 1341-1349 ◽  
Author(s):  
Fabrice Vandeput ◽  
Sandrine Perpete ◽  
Katia Coulonval ◽  
Françoise Lamy ◽  
Jacques E. Dumont
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Protein Kinase ◽  
Epidermal Growth Factor ◽  
Dna Synthesis ◽  
P38 Mapk ◽  
Primary Cultures ◽  
Human Thyroid ◽  
Epidermal Growth

Abstract We have investigated the role of the different classes of MAPKs, i.e. ERKs, c-Jun N-terminal kinases (JNKs), and p38 MAPK in the proliferation of dog and human thyroid epithelial cells (thyrocytes) in primary cultures. In these cells, TSH, acting through cAMP, epidermal growth factor, hepatocyte growth factor (HGF), and phorbol 12-myristate 13-acetate induce DNA synthesis. With the exception of HGF, all of these factors require the presence of insulin for mitogenic effects to be expressed. We found that TSH and forskolin are without effect on the phosphorylation and activity of the different classes of MAPKs. In contrast, all the cAMP-independent growth factors, whereas without effect on the phosphorylation and activity of JNKs and p38 MAPK, stimulated the ERKs. This effect was strong and sustained in response to HGF, epidermal growth factor and 12-myristate 13-acetate but weak and transient in response to insulin. Moreover, whereas in stimulated cells DNA synthesis was inhibited by PD 098059, an inhibitor of MAPK kinase 1 and consequently of ERKs, it was not modified by SB 203580, an inhibitor of p38 MAPK. Taken together, these data 1) exclude a role of JNKs and p38 MAPK in the proliferation of dog and human thyrocytes; 2) suggest that the mitogenic action of the cAMP-independent agents requires a strong and sustained activation of both ERKs and phosphatidylinositol 3-kinase/protein kinase B as realized by HGF alone or by the other agents together with insulin; and 3) show that TSH and cAMP do not activate ERKs but that the weak activation of ERKs by insulin is nevertheless necessary for DNA synthesis to occur.

scholarly journals EGF Induces Migration Independent of EMT or Invasion in A549 Lung Adenocarcinoma Cells

2021 ◽  
Vol 9 ◽  
Author(s):  
Karin Schelch ◽  
Lisa Vogel ◽  
Anja Schneller ◽  
Jelena Brankovic ◽  
Thomas Mohr ◽  
...  
Keyword(s):  
Cell Migration ◽  
Growth Factors ◽  
Growth Factor ◽  
Lung Adenocarcinoma ◽  
Expression Patterns ◽  
Migration And Invasion ◽  
Adenocarcinoma Cells ◽  
Lung Adenocarcinoma Cells ◽  
Related Proteins ◽  
A549 Lung

Tumors and the tumor microenvironment produce multiple growth factors that influence cancer cell behavior via various signal transduction pathways. Growth factors, like transforming growth factor β (TGFβ) and epidermal growth factor (EGF), have been shown to induce proliferation, migration, and invasion in different cell models. Both factors are frequently overexpressed in cancer and will often act in combination. Although both factors are being used as rational targets in clinical oncology, the similarities and differences of their contributions to cancer cell migration and invasion are not fully understood. Here we compared the impact of treating A549 lung adenocarcinoma cells with TGFβ, EGF, and both in combination by applying videomicroscopy, functional assays, immunoblotting, real-time PCR, and proteomics. Treatment with both factors stimulated A549 migration to a similar extent, but with different kinetics. The combination had an additive effect. EGF-induced migration depended on activation of the mitogen-activated protein kinase (MAPK) pathway. However, this pathway was dispensable for TGFβ-induced migration, despite a strong activation of this pathway by TGFβ. Proteome analysis (data are available via ProteomeXchange with identifier PXD023024) revealed an overlap in expression patterns of migration-related proteins and associated gene ontology (GO) terms by TGFβ and EGF. Further, only TGFβ induced the expression of epithelial to mesenchymal transition (EMT)-related proteins like matrix metalloproteinase 2 (MMP2). EGF, in contrast, made no major contribution to EMT marker expression on either the protein or the transcript level. In line with these expression patterns, TGFβ treatment significantly increased the invasive capacity of A549 cells, while EGF treatment did not. Moreover, the addition of EGF failed to enhance TGFβ-induced invasion. Overall, these data suggest that TGFβ and EGF can partly compensate for each other for stimulation of cell migration, but abrogation of TGFβ signaling may be more suitable to suppress cell invasion.

Paracrine control of gastric epithelial cell growth in culture by transforming growth factor-alpha

1993 ◽  
Vol 264 (2) ◽  
pp. G390-G396 ◽  
Author(s):  
M. C. Chen ◽  
A. T. Lee ◽  
W. E. Karnes ◽  
D. Avedian ◽  
M. Martin ◽  
...  
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Cell Growth ◽  
Transforming Growth Factor ◽  
Cultured Cells ◽  
Thymidine Incorporation ◽  
Primary Cultures ◽  
Transforming Growth Factor Alpha ◽  
Mucosal Cell ◽  
Factor Alpha

Studying primary cultures of replicating canine oxyntic mucosal cells, we found evidence for modulation of cell growth by endogenous factors. [3H]thymidine incorporation into DNA was rapid with cells cultured in medium free of serum or added growth factors, and growth rates of these cultures were markedly dependent on plating density, indicating mitogenic control by soluble endogenous growth factors. Data indicated that endogenous transforming growth factor-alpha (TGF-alpha) exerted mitogenic control under the following conditions. 1) TGF-alpha was detected in the cultured cells by radioimmunoassay and immunohistochemistry. 2) TGF-alpha-like immunoreactivity and receptor reactivity were present in the medium in concentrations sufficient to exert mitogenic control. 3) Receptors for TGF-alpha and epidermal growth factor (EGF) were present in the cultures. 4) Immunoabsorption by a TGF-alpha-specific antisera reduced [3H]thymidine incorporation. TGF-alpha was localized to parietal cells by immunohistochemistry and cell separation. In contrast, combined [3H]thymidine autoradiography and immunohistochemistry with anti-TGF-alpha did not detect TGF-alpha in dividing cells. We conclude that parietal cell TGF-alpha exerts paracrine control of mucosal cell growth in vitro, and we speculate that this is an important paracrine mechanism in vivo.

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