The growth-stimulatory effect of simian virus 40 T antigen requires the interaction of insulinlike growth factor 1 with its receptor

1992 ◽  
Vol 12 (11) ◽  
pp. 5069-5077
Author(s):  
P Porcu ◽  
A Ferber ◽  
Z Pietrzkowski ◽  
C T Roberts ◽  
M Adamo ◽  
...  
Keyword(s):  
Growth Factor ◽  
Simian Virus 40 ◽  
Simian Virus ◽  
T Antigen ◽  
Serum Free Medium ◽  
Free Medium ◽  
3T3 Cells ◽  
Sv40 T Antigen ◽  
Serum Free ◽  
Insulinlike Growth Factor

We have used a plasmid expressing a temperature-sensitive (ts) mutant of simian virus 40 (SV40) T antigen, stably transfected into 3T3 cells, to study the role of insulinlike growth factor 1 (IGF-1) and its receptor in T-antigen-mediated growth. While 3T3 cells do not grow in serum-free medium, in 1% serum, or with the sole addition of either platelet-derived growth factor (PDGF) or IGF-1, cells expressing the tsA T antigen (BALB 58 cells) grow at 34 degrees C in either PDGF or 1% serum but not in IGF-1. At the restrictive temperature (39.6 degrees C), these cells can only grow in 10% serum. We show that BALB 58 cells, at 34 degrees C, have a markedly increased expression of IGF-1 and IGF-1 mRNA and that their growth in 1% serum (at 34 degrees C) is inhibited by an antisense oligodeoxynucleotide to the IGF-1 receptor RNA. When this tsA plasmid is stably transfected into cells constitutively overexpressing the human IGF-1 receptor cDNA, the resulting cell lines show a constitutively phosphorylated IGF-1 receptor and grow in serum-free medium at 34 degrees C (but not at 39.6 degrees C). A functional SV40 T antigen also increases the expression of a plasmid in which the reporter luciferase gene is under the control of a rat IGF-1 promoter. We conclude (i) that the SV40 T antigen induces the expression of IGF-1 and IGF-1 mRNA, at least in part by a transcriptional mechanism, thus altering the growth factors requirements, and (ii) that, in BALB/c3t3 cells, the SV40 T antigen necessitates a functional IGF-1 receptor for its growth-stimulating effect in low serum (or PDGF).

scholarly journals The growth-stimulatory effect of simian virus 40 T antigen requires the interaction of insulinlike growth factor 1 with its receptor.

1992 ◽  
Vol 12 (11) ◽  
pp. 5069-5077 ◽  
Author(s):  
P Porcu ◽  
A Ferber ◽  
Z Pietrzkowski ◽  
C T Roberts ◽  
M Adamo ◽  
...  
Keyword(s):  
Growth Factor ◽  
Simian Virus 40 ◽  
Simian Virus ◽  
T Antigen ◽  
Serum Free Medium ◽  
Free Medium ◽  
3T3 Cells ◽  
Sv40 T Antigen ◽  
Serum Free ◽  
Insulinlike Growth Factor

We have used a plasmid expressing a temperature-sensitive (ts) mutant of simian virus 40 (SV40) T antigen, stably transfected into 3T3 cells, to study the role of insulinlike growth factor 1 (IGF-1) and its receptor in T-antigen-mediated growth. While 3T3 cells do not grow in serum-free medium, in 1% serum, or with the sole addition of either platelet-derived growth factor (PDGF) or IGF-1, cells expressing the tsA T antigen (BALB 58 cells) grow at 34 degrees C in either PDGF or 1% serum but not in IGF-1. At the restrictive temperature (39.6 degrees C), these cells can only grow in 10% serum. We show that BALB 58 cells, at 34 degrees C, have a markedly increased expression of IGF-1 and IGF-1 mRNA and that their growth in 1% serum (at 34 degrees C) is inhibited by an antisense oligodeoxynucleotide to the IGF-1 receptor RNA. When this tsA plasmid is stably transfected into cells constitutively overexpressing the human IGF-1 receptor cDNA, the resulting cell lines show a constitutively phosphorylated IGF-1 receptor and grow in serum-free medium at 34 degrees C (but not at 39.6 degrees C). A functional SV40 T antigen also increases the expression of a plasmid in which the reporter luciferase gene is under the control of a rat IGF-1 promoter. We conclude (i) that the SV40 T antigen induces the expression of IGF-1 and IGF-1 mRNA, at least in part by a transcriptional mechanism, thus altering the growth factors requirements, and (ii) that, in BALB/c3t3 cells, the SV40 T antigen necessitates a functional IGF-1 receptor for its growth-stimulating effect in low serum (or PDGF).

Roles of insulinlike growth factor 1 (IGF-1) and the IGF-1 receptor in epidermal growth factor-stimulated growth of 3T3 cells

1992 ◽  
Vol 12 (9) ◽  
pp. 3883-3889
Author(s):  
Z Pietrzkowski ◽  
C Sell ◽  
R Lammers ◽  
A Ullrich ◽  
R Baserga
Keyword(s):  
Growth Factor ◽  
Cell Growth ◽  
Epidermal Growth Factor ◽  
Platelet Derived Growth Factor ◽  
Serum Free Medium ◽  
Free Medium ◽  
3T3 Cells ◽  
Serum Free ◽  
Insulinlike Growth Factor ◽  
Epidermal Growth

BALB/c3T3 cells are exquisitely growth regulated and require platelet-derived growth factor, epidermal growth factor (EGF), and insulinlike growth factor 1 (IGF-1) for growth. When BALB/c3T3 cells are transfected with plasmids constitutively expressing both EGF and the human IGF-1 receptor mRNAs, the cells are capable of growing in serum-free medium without the addition of any exogenous growth factor. These cells, called p5 cells, can grow for prolonged periods in serum-free medium. BALB/c3T3 cells transfected with only the IGF-1 receptor expression plasmid (p6 cells) do not grow in serum-free medium but do grow if IGF-1 (or insulin in supraphysiological concentrations) is added. p6 cells also grow in response to EGF, confirming that the combination of EGF and an overexpressed IGF-1 receptor is sufficient for the growth of 3T3 cells. We have found that in EGF-stimulated p6 cells there is an increase in the expression of IGF-1 mRNA, that IGF-1 is secreted into the medium, and that the growth of p5 cells and EGF-stimulated p6 cells is inhibited by exposure to antisense oligodeoxynucleotides to IGF-1 receptor RNA. Finally, while cells constitutively expressing both EGF and EGF receptor RNAs grow, albeit modestly, in serum-free medium, their growth is also inhibited by an antisense oligodeoxynucleotide to IGF-1 receptor RNA. In contrast, in cells overexpressing the IGF-1 receptor, IGF-1-mediated cell growth occurs independently of the platelet-derived growth factor and EGF receptors (Z. Pietrzkowski, R. Lammers, G. Carpenter, A. M. Soderquist, M. Limardo, P. D. Phillips, A. Ullrich, and R. Baserga, Cell Growth Differ. 3:199-205, 1992, and this paper). These data indicate that an important role for EGF is participation in the activation of an autocrine loop based on the IGF-1-IGF-1 receptor interaction, which is obligatory for the proliferation of 3T3 cells.

scholarly journals Roles of insulinlike growth factor 1 (IGF-1) and the IGF-1 receptor in epidermal growth factor-stimulated growth of 3T3 cells.

1992 ◽  
Vol 12 (9) ◽  
pp. 3883-3889 ◽  
Author(s):  
Z Pietrzkowski ◽  
C Sell ◽  
R Lammers ◽  
A Ullrich ◽  
R Baserga
Keyword(s):  
Growth Factor ◽  
Cell Growth ◽  
Epidermal Growth Factor ◽  
Platelet Derived Growth Factor ◽  
Serum Free Medium ◽  
Free Medium ◽  
3T3 Cells ◽  
Serum Free ◽  
Insulinlike Growth Factor ◽  
Epidermal Growth

BALB/c3T3 cells are exquisitely growth regulated and require platelet-derived growth factor, epidermal growth factor (EGF), and insulinlike growth factor 1 (IGF-1) for growth. When BALB/c3T3 cells are transfected with plasmids constitutively expressing both EGF and the human IGF-1 receptor mRNAs, the cells are capable of growing in serum-free medium without the addition of any exogenous growth factor. These cells, called p5 cells, can grow for prolonged periods in serum-free medium. BALB/c3T3 cells transfected with only the IGF-1 receptor expression plasmid (p6 cells) do not grow in serum-free medium but do grow if IGF-1 (or insulin in supraphysiological concentrations) is added. p6 cells also grow in response to EGF, confirming that the combination of EGF and an overexpressed IGF-1 receptor is sufficient for the growth of 3T3 cells. We have found that in EGF-stimulated p6 cells there is an increase in the expression of IGF-1 mRNA, that IGF-1 is secreted into the medium, and that the growth of p5 cells and EGF-stimulated p6 cells is inhibited by exposure to antisense oligodeoxynucleotides to IGF-1 receptor RNA. Finally, while cells constitutively expressing both EGF and EGF receptor RNAs grow, albeit modestly, in serum-free medium, their growth is also inhibited by an antisense oligodeoxynucleotide to IGF-1 receptor RNA. In contrast, in cells overexpressing the IGF-1 receptor, IGF-1-mediated cell growth occurs independently of the platelet-derived growth factor and EGF receptors (Z. Pietrzkowski, R. Lammers, G. Carpenter, A. M. Soderquist, M. Limardo, P. D. Phillips, A. Ullrich, and R. Baserga, Cell Growth Differ. 3:199-205, 1992, and this paper). These data indicate that an important role for EGF is participation in the activation of an autocrine loop based on the IGF-1-IGF-1 receptor interaction, which is obligatory for the proliferation of 3T3 cells.

The K-fgf/hst oncogene induces transformation through an autocrine mechanism that requires extracellular stimulation of the mitogenic pathway

1991 ◽  
Vol 11 (2) ◽  
pp. 1138-1145
Author(s):  
D Talarico ◽  
C Basilico
Keyword(s):  
Growth Factor ◽  
Receptor Activation ◽  
Soft Agar ◽  
Serum Free Medium ◽  
Free Medium ◽  
3T3 Cells ◽  
Serum Free ◽  
Nih 3T3 ◽  
Autocrine Mechanism ◽  
Nih 3T3 Cells

The K-fgf/hst oncogene encodes a secreted growth factor of the fibroblast growth factor (FGF) family. The ability of K-fgf-transformed cells to grow in soft agar and in serum-free medium is inhibited by anti-K-FGF neutralizing antibodies, consistent with an autocrine mechanism of transformation. The transformed properties of clones that express high levels of K-FGF are, however, only partially affected. To better define the autocrine mechanism of transformation by K-fgf and to determine whether receptor activation could occur intracellularly, we constructed two mutants of the K-fgf cDNA. Deletion of the sequences encoding the signal peptide suppressed K-fgf ability to induce foci in NIH 3T3 cells. A few morphologically transformed colonies were observed in cotransfection experiments, and they were found to express high levels of cytoplasmic K-FGF. However, their ability to grow in serum-free medium and in soft agar was inhibited by anti-K-FGF antibodies. Addition of a sequence encoding the KDEL endoplasmic reticulum and Golgi retention signal to the K-fgf cDNA led to accumulation of the growth factor in intracellular compartments. The ability of the KDEL mutant to induce foci in NIH 3T3 cells was much lower than that of the wild-type cDNA, and also in this case the transformed phenotype was reverted by anti-K-FGF antibodies. These and other findings indicate that the transformed phenotype of cells expressing a nonsecretory K-FGF is due to the extracellular activation of the receptor by the small amounts of growth factor that these cells still release. Thus, transformation by K-fgf appears to be due to an autocrine growth mechanisms that requires activation of the mitogenic pathway at the cell surface.

scholarly journals Constitutively expressed c-myb abrogates the requirement for insulinlike growth factor 1 in 3T3 fibroblasts.

1991 ◽  
Vol 11 (2) ◽  
pp. 731-736 ◽  
Author(s):  
S Travali ◽  
K Reiss ◽  
A Ferber ◽  
S Petralia ◽  
W E Mercer ◽  
...  
Keyword(s):  
Growth Factor ◽  
Cell Types ◽  
Simian Virus ◽  
S Phase ◽  
Platelet Derived Growth Factor ◽  
Parent Cell ◽  
3T3 Cells ◽  
Serum Free ◽  
Platelet Poor Plasma ◽  
Insulinlike Growth Factor

The proto-oncogene c-myb, whose expression is usually limited to cells of the hematopoietic lineages, can be expressed in fibroblasts if placed under the control of a constitutive promoter, such as the simian virus SV40 early promoter. 3T3 cells carrying a constitutively expressed human c-myb were found to grow in 1% serum or in a serum-free, platelet-derived growth factor-supplemented medium, whereas the parent cell line, BALB/c 3T3, needed insulinlike growth factor 1 (IGF-1) in addition to platelet-derived growth factor for growth. myb-carrying cells, however, could not grow in platelet-poor plasma. In fibroblasts, therefore, a constitutively expressed c-myb can abrogate the requirement for platelet-poor plasma or IGF-1. When 3T3 cells constitutively expressed both c-myc and c-myb, they could grow in serum-free medium without added growth factors. The ability of c-myb to abrogate in fibroblasts the IGF-1 requirement seems to be due to its ability to induce overexpression of IGF-1, as indicated by an increase in steady-state levels of IGF-1 mRNA. These results have some important implications; for instance, they suggest a commonality of pathways for entry into S phase in different cell types and the possibility of a myb-like or myb-equivalent gene product of critical importance for entry of fibroblasts into S phase.

scholarly journals The K-fgf/hst oncogene induces transformation through an autocrine mechanism that requires extracellular stimulation of the mitogenic pathway.

1991 ◽  
Vol 11 (2) ◽  
pp. 1138-1145 ◽  
Author(s):  
D Talarico ◽  
C Basilico
Keyword(s):  
Growth Factor ◽  
Receptor Activation ◽  
Soft Agar ◽  
Serum Free Medium ◽  
Free Medium ◽  
3T3 Cells ◽  
Serum Free ◽  
Nih 3T3 ◽  
Autocrine Mechanism ◽  
Nih 3T3 Cells

The K-fgf/hst oncogene encodes a secreted growth factor of the fibroblast growth factor (FGF) family. The ability of K-fgf-transformed cells to grow in soft agar and in serum-free medium is inhibited by anti-K-FGF neutralizing antibodies, consistent with an autocrine mechanism of transformation. The transformed properties of clones that express high levels of K-FGF are, however, only partially affected. To better define the autocrine mechanism of transformation by K-fgf and to determine whether receptor activation could occur intracellularly, we constructed two mutants of the K-fgf cDNA. Deletion of the sequences encoding the signal peptide suppressed K-fgf ability to induce foci in NIH 3T3 cells. A few morphologically transformed colonies were observed in cotransfection experiments, and they were found to express high levels of cytoplasmic K-FGF. However, their ability to grow in serum-free medium and in soft agar was inhibited by anti-K-FGF antibodies. Addition of a sequence encoding the KDEL endoplasmic reticulum and Golgi retention signal to the K-fgf cDNA led to accumulation of the growth factor in intracellular compartments. The ability of the KDEL mutant to induce foci in NIH 3T3 cells was much lower than that of the wild-type cDNA, and also in this case the transformed phenotype was reverted by anti-K-FGF antibodies. These and other findings indicate that the transformed phenotype of cells expressing a nonsecretory K-FGF is due to the extracellular activation of the receptor by the small amounts of growth factor that these cells still release. Thus, transformation by K-fgf appears to be due to an autocrine growth mechanisms that requires activation of the mitogenic pathway at the cell surface.

A multicenter phase II study of pemetrexed (P), cisplatin (C), and bevacizumab (B) in patients (pts) with advanced malignant mesothelioma (MM)

2009 ◽  
Vol 27 (15_suppl) ◽  
pp. 7578-7578 ◽  
Author(s):  
J. Dowell ◽  
R. Taub ◽  
C. Lan ◽  
Y. Xie ◽  
F. Dunphy ◽  
...  
Keyword(s):  
Growth Factor ◽  
Phase Ii ◽  
Simian Virus 40 ◽  
Progression Free Survival ◽  
Simian Virus ◽  
T Antigen ◽  
Sv40 T Antigen ◽  
Anti Vegf ◽  
Correlative Studies ◽  
Multi Center Study

7578 Background: Vascular endothelial growth factor (VEGF) is a key growth factor for MM. In pre-clinical models, anti-VEGF antibodies inhibit MM proliferation. Standard chemotherapy for MM, pemetrexed + cisplatin, yields a response rate of 41%, progression-free survival (PFS) of 5.7 months (mo) and median overall survival (OS) of 12.1 mo. We added the anti-VEGF antibody B to PC in an ongoing phase II multi-center study in MM pts. Methods: Eligible pts have unresectable, histologically-confirmed MM, no prior chemotherapy, and PS 0–1. Pts receive C 75 mg/m2, P 500 mg/m2 and B 15 mg/kg Q21 days for 6 cycles, then B Q21 days until progression. CT scans are obtained Q 2 cycles. Primary endpoint: Progression-fere survival (PFS). Correlative studies include IHC for the VEGF/KDR complex and PCR for simian virus 40 (sv40) T antigen. Results: 43 pts enrolled at 4 centers from 3/06 to 12/08; currently, 34 are evaluable for PFS and 36 for toxicity. Pt characteristics: male 88%; median age 66 (range 24–81); histology: epithelial 62%, sarcomatoid 15%, biphasic 20%, unknown 3%; site of origin: pleural 85%, peritoneal 12%, tunica vaginalis 3%; PS 0 32%, PS 1 68%; thrombocytosis (>400) 32%. Cycles administered 229 (median 4, range 1–18). Grade 3/4 toxicity (%pts): neutropenia 8%; anemia 0%; thrombocytopenia 3%; thrombosis 11%; hypertension 8%; vomiting 8%; mucositis 6%; CVA 3%; proteinuria 0%; perforation 0%. Partial response: 41%, stable disease: 35%. Median PFS: 5.6 mo (95% CI: 4.1, 7.2). Median OS 11.5 mo (95% CI: 9.4, 24). Conclusions: These data suggest that the addition of B to PC does not improve PFS when compared with historical controls of PC in advanced MM pts. Correlative studies evaluating the VEGF/KDR complex and sv40 T antigen are pending. [Table: see text]

scholarly journals Effect of a null mutation of the insulin-like growth factor I receptor gene on growth and transformation of mouse embryo fibroblasts.

1994 ◽  
Vol 14 (6) ◽  
pp. 3604-3612 ◽  
Author(s):  
C Sell ◽  
G Dumenil ◽  
C Deveaud ◽  
M Miura ◽  
D Coppola ◽  
...  
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Soft Agar ◽  
T Antigen ◽  
Insulin Like Growth Factor ◽  
Serum Free Medium ◽  
Free Medium ◽  
Serum Free ◽  
Factor I ◽  
Growth Factor I

Fibroblast cell lines, designated R- and W cells, were generated, respectively, from mouse embryos homozygous for a targeted disruption of the Igf1r gene, encoding the type 1 insulin-like growth factor receptor, and from their wild-type littermates. W cells grow normally in serum-free medium supplemented with various combinations of purified growth factors, while pre- and postcrisis R- cells cannot grow, as they are arrested before entering the S phase. R- cells are able to grow in 10% serum, albeit more slowly than W cells, and with all phases of the cell cycle being elongated. An activated Ha-ras expressed from a stably transfected plasmid is unable to overcome the inability of R- cells to grow in serum-free medium supplemented with purified clones. Nevertheless, even in the presence of serum, R- cells stably transfected with Ha-ras, alone or in combination with simian virus 40 large T antigen, fail to form colonies in soft agar. Reintroduction into R- cells (or their derivatives) of a plasmid expressing the human insulin-like growth factor I receptor RNA and protein restores their ability to grow with purified growth factors or in soft agar. The signaling pathways participating in cell growth and transformation are discussed on the basis of these results.

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