scholarly journals Expression and biosynthetic variation of the epidermal growth factor receptor in human hepatocellular carcinoma-derived cell lines.

1988 ◽  
Vol 8 (1) ◽  
pp. 25-34 ◽  
Author(s):  
C R Carlin ◽  
D Simon ◽  
J Mattison ◽  
B B Knowles
Keyword(s):  
Hepatocellular Carcinoma ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Cell Line ◽  
Cell Lines ◽  
Gene Amplification ◽  
Egf Receptor ◽  
Hepatoma Cell ◽  
Receptor Gene ◽  
Epidermal Growth

Expression of the epidermal growth factor (EGF) was analyzed in six human hepatocellular carcinoma-derived and one human hepatoblastoma-derived cell line, each of which retained the differentiated phenotype and functions of the parenchymal hepatocyte. The level of receptor expression of each hepatoma cell line was similar to that of the normal human fibroblast, approximately 10(5) molecules per cell. However, NPLC/PRF/5, a subline of the PLC/PRF/5 cell line obtained following reestablishment of a xenograft tumor in vitro, was found to express 4 x 10(6) high-affinity EGF receptor molecules per cell. Proliferation of the NPLC/PRF/5 cell line was inhibited in the presence of nanomolar quantities of ligand. Receptor overexpression was found to result from EGF receptor gene amplification without apparent rearrangement of the EGF receptor coding sequences. Although cell-specific variability in posttranslational processing of EGF receptor N-linked oligosaccharides in the hepatoma cell lines was found, no difference between the receptors in PLC/PRF/5 and NPLC/PRF/5 was observed and no aberrant receptor-related species were detected. EGF receptor gene amplification in the NPLC/PRF/5 cell line is probably a reflection of genome instability and selection of variants with augmented growth potential in limiting concentrations of EGF in vivo. When viewed in this light, EGF receptor overexpression could represent a manifestation of tumor progression in the EGF-responsive hepatocyte.

Expression and biosynthetic variation of the epidermal growth factor receptor in human hepatocellular carcinoma-derived cell lines

1988 ◽  
Vol 8 (1) ◽  
pp. 25-34
Author(s):  
C R Carlin ◽  
D Simon ◽  
J Mattison ◽  
B B Knowles
Keyword(s):  
Hepatocellular Carcinoma ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Cell Line ◽  
Cell Lines ◽  
Gene Amplification ◽  
Egf Receptor ◽  
Hepatoma Cell ◽  
Receptor Gene ◽  
Epidermal Growth

Expression of the epidermal growth factor (EGF) was analyzed in six human hepatocellular carcinoma-derived and one human hepatoblastoma-derived cell line, each of which retained the differentiated phenotype and functions of the parenchymal hepatocyte. The level of receptor expression of each hepatoma cell line was similar to that of the normal human fibroblast, approximately 10(5) molecules per cell. However, NPLC/PRF/5, a subline of the PLC/PRF/5 cell line obtained following reestablishment of a xenograft tumor in vitro, was found to express 4 x 10(6) high-affinity EGF receptor molecules per cell. Proliferation of the NPLC/PRF/5 cell line was inhibited in the presence of nanomolar quantities of ligand. Receptor overexpression was found to result from EGF receptor gene amplification without apparent rearrangement of the EGF receptor coding sequences. Although cell-specific variability in posttranslational processing of EGF receptor N-linked oligosaccharides in the hepatoma cell lines was found, no difference between the receptors in PLC/PRF/5 and NPLC/PRF/5 was observed and no aberrant receptor-related species were detected. EGF receptor gene amplification in the NPLC/PRF/5 cell line is probably a reflection of genome instability and selection of variants with augmented growth potential in limiting concentrations of EGF in vivo. When viewed in this light, EGF receptor overexpression could represent a manifestation of tumor progression in the EGF-responsive hepatocyte.

scholarly journals Epidermal growth factor-induced proliferation of collecting duct cells from Oak Ridge polycystic kidney mice involves activation of Na+/H+ exchanger

2014 ◽  
Vol 307 (6) ◽  
pp. C554-C560 ◽  
Author(s):  
Sonya D. Coaxum ◽  
Mary G. Blanton ◽  
Alisha Joyner ◽  
Tanjina Akter ◽  
P. Darwin Bell ◽  
...  
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Cell Line ◽  
Cell Lines ◽  
Egf Receptor ◽  
Collecting Duct ◽  
Polycystic Kidney ◽  
Oak Ridge ◽  
Erk Phosphorylation ◽  
Epidermal Growth

Epidermal growth factor (EGF) is linked to the pathogenesis of polycystic kidney disease (PKD). We explored signaling pathways activated by EGF in orpk cilia (−) collecting duct cell line derived from a mouse model of PKD (hypomorph of the Tg737/ Ift88 gene) with severely stunted cilia, and in a control orpk cilia (+) cell line with normal cilia. RT-PCR demonstrated mRNAs for EGF receptor subunits ErbB1, ErbB2, ErbB3, ErbB4, and mRNAs for Na+/H+ exchangers (NHE), NHE-1, NHE-2, NHE-3, NHE-4, and NHE-5 in both cell lines. EGF stimulated proton efflux in both cell lines. This effect was significantly attenuated by MIA, 5-( n-methyl- N-isobutyl) amiloride, a selective inhibitor of NHE-1 and NHE-2, and orpk cilia (−) cells were more sensitive to MIA than control cells ( P < 0.01). EGF significantly induced extracellular signal-regulated kinase (ERK) phosphorylation in both cilia (+) and cilia (−) cells (63.3 and 123.6%, respectively), but the effect was more pronounced in orpk cilia (−) cells ( P < 0.01). MIA significantly attenuated EGF-induced ERK phosphorylation only in orpk cilia (−) cells ( P < 0.01). EGF increased proliferation of orpk cilia (+) cells and orpk cilia (−) cells, respectively, and MIA at 1–5 μM attenuated EGF-induced proliferation in orpk cilia (−) cells without affecting proliferation of orpk cilia (+) cells. EGF-induced proliferation of both cell lines was significantly decreased by the EGFR tyrosine kinase inhibitor AG1478 and MEK inhibitor PD98059. These results suggest that EGF exerts mitogenic effects in the orpk cilia (−) cells via activation of growth-associated amiloride-sensitive NHEs and ERK.

scholarly journals Epidermal growth factor receptor gene-amplified MDA-468 breast cancer cell line and its nonamplified variants.

1987 ◽  
Vol 7 (1) ◽  
pp. 251-257 ◽  
Author(s):  
J Filmus ◽  
J M Trent ◽  
M N Pollak ◽  
R N Buick
Keyword(s):  
Breast Cancer ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Cell Line ◽  
Breast Cancer Cell Line ◽  
Egf Receptor ◽  
Receptor Gene ◽  
Cancer Cell Line ◽  
Egf Receptors ◽  
Epidermal Growth

We have recently reported (J. Filmus, M. N. Pollak, R. Cailleau, and R. N. Buick, Biochem. Biophys. Res. Commun. 128:898-905, 1985) that MDA-468, a human breast cancer cell line with a high number of epidermal growth factor (EGF) receptors, has an amplified EGF receptor gene and is growth inhibited in vitro pharmacological doses of EGF. We have derived several MDA-468 clonal variants which are resistant to EGF-induced growth inhibition. These clones had a number of EGF receptors, similar to normal human fibroblasts, and had lost the EGF receptor gene amplification. Karyotype analysis showed that MDA-468 cells had an abnormally banded region (ABR) in chromosome 7p which was not present in the variants. It was shown by in situ hybridization that the amplified EGF receptor sequences were located in that chromosome, 7pABR. Five of the six variants studied were able to generate tumors in nude mice, but their growth rate was significantly lower than that of tumors derived from the parental cell line. The variant that was unable to produce tumors was found to be uniquely dependent on EGF for growth in soft agar.

scholarly journals Epidermal growth factor receptor gene-amplified MDA-468 breast cancer cell line and its nonamplified variants

1987 ◽  
Vol 7 (1) ◽  
pp. 251-257
Author(s):  
J Filmus ◽  
J M Trent ◽  
M N Pollak ◽  
R N Buick
Keyword(s):  
Breast Cancer ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Cell Line ◽  
Breast Cancer Cell Line ◽  
Egf Receptor ◽  
Receptor Gene ◽  
Cancer Cell Line ◽  
Egf Receptors ◽  
Epidermal Growth

We have recently reported (J. Filmus, M. N. Pollak, R. Cailleau, and R. N. Buick, Biochem. Biophys. Res. Commun. 128:898-905, 1985) that MDA-468, a human breast cancer cell line with a high number of epidermal growth factor (EGF) receptors, has an amplified EGF receptor gene and is growth inhibited in vitro pharmacological doses of EGF. We have derived several MDA-468 clonal variants which are resistant to EGF-induced growth inhibition. These clones had a number of EGF receptors, similar to normal human fibroblasts, and had lost the EGF receptor gene amplification. Karyotype analysis showed that MDA-468 cells had an abnormally banded region (ABR) in chromosome 7p which was not present in the variants. It was shown by in situ hybridization that the amplified EGF receptor sequences were located in that chromosome, 7pABR. Five of the six variants studied were able to generate tumors in nude mice, but their growth rate was significantly lower than that of tumors derived from the parental cell line. The variant that was unable to produce tumors was found to be uniquely dependent on EGF for growth in soft agar.

Modulation of epidermal growth factor receptor proto-oncogene transcription by a promoter site sensitive to S1 nuclease

1988 ◽  
Vol 8 (10) ◽  
pp. 4174-4184
Author(s):  
A C Johnson ◽  
Y Jinno ◽  
G T Merlino
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Egf Receptor ◽  
Receptor Gene ◽  
Gene Promoter ◽  
Direct Repeat ◽  
S1 Nuclease ◽  
Epidermal Growth ◽  
Specific Factors

The epidermal growth factor (EGF) receptor is the functional target of the mitogen EGF and the cellular homolog of the avian erythroblastosis virus erbB oncogene product. Regulation of expression of the proto-oncogene encoding the EGF receptor can be elucidated by studying the structure and function of the gene promoter outside the confines of the cell. Previously, we reported the isolation of the human EGF receptor gene promoter. The promoter is highly GC rich, contains no TATA or CAAT box, and has multiple transcription start sites. An S1 nuclease-sensitive site has now been found 80 to 110 base pairs (bp) upstream from the major in vivo transcription initiation site. Two sets of direct repeat sequences were found in this area; both conform to the motif TCCTCCTCC. When deletion mutations were made in this region of the promoter by using either Bal 31 exonuclease or S1 nuclease, we found that in vivo activity dropped three- to fivefold, on the basis of transient-transfection analysis. Examination of nuclear protein binding to normal and mutated promoter DNAs by gel retardation analysis and DNase I footprinting revealed that two specific factors bind to the direct repeat region but cannot bind to the S1 nuclease-mutated promoter. One of the specific factors is the transcription factor Sp1. The results suggest that these nuclear trans-acting factors interact with the S1 nuclease-sensitive region of the EGF receptor gene promoter and either directly or indirectly stimulate transcription.

scholarly journals Membrane-anchored Heparin-binding Epidermal Growth Factor-like Growth Factor Acts as a Tumor Survival Factor in a Hepatoma Cell Line

1997 ◽  
Vol 272 (22) ◽  
pp. 14349-14355 ◽  
Author(s):  
Eiji Miyoshi ◽  
Shigeki Higashiyama ◽  
Takatoshi Nakagawa ◽  
Norio Hayashi ◽  
Naoyuki Taniguchi
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Cell Line ◽  
Hepatoma Cell ◽  
Hepatoma Cell Line ◽  
Heparin Binding ◽  
Survival Factor ◽  
Tumor Survival ◽  
Epidermal Growth
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