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Autocrine stimulation of growth of AR4-2J rat pancreatic tumour cells by gastrin.

The control of cell proliferation by gastrin has been investigated in a rat pancreatic tumour cell line, AR4-2J. Exogenous gastrin, 10(-12) to 10(-8) M, stimulated cell growth of thymidine-synchronised AR4-2J cells cultured over 48 h in serum-free medium. Cell lysates of AR4-2J cells contained an av...

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Autores principales: Blackmore, M., Hirst, B. H.
Formato: Texto
Lenguaje:English
Publicado: Nature Publishing Group 1992
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1977912/
https://www.ncbi.nlm.nih.gov/pubmed/1637673
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author Blackmore, M.
Hirst, B. H.
author_facet Blackmore, M.
Hirst, B. H.
author_sort Blackmore, M.
collection PubMed
description The control of cell proliferation by gastrin has been investigated in a rat pancreatic tumour cell line, AR4-2J. Exogenous gastrin, 10(-12) to 10(-8) M, stimulated cell growth of thymidine-synchronised AR4-2J cells cultured over 48 h in serum-free medium. Cell lysates of AR4-2J cells contained an average of 4.5 and 3.5 pg gastrin per 10(6) cells, when grown in serum-supplemented or serum-free media, respectively, as revealed by radioimmunoassay. In serum-free medium, AR4-2J secrete 34 ng 1(-1) 10(-6) cells of gastrin over 48 h. Addition of an anti-gastrin immunoglobulin preparation, but not control immunoglobulins, caused a maximum 52% reduction in cell growth. These data are consistent with an autocrine role for gastrin in the control of AR4-2J cell growth. These results were supported by studies with gastrin/CCK receptor antagonists. Six non-peptide gastrin/CCK receptor antagonists inhibited AR4-2J cell growth in a concentration-related manner. The concentration required for 50% inhibition (IC50) of cell growth by the amino acid-derived antagonists proglumide (3.5 x 10(-3) M), benzotript (1.8 x 10(-3) M), loxiglumide (1.1 x 10(-4) M) and lorglumide (6.7 x 10(-5) M) were of the same order and significantly correlated with their IC50 for inhibition of 125I-gastrin binding to AR4-2J cells. Inhibition of cell growth by these antagonists was partially reversed by the addition of exogenous gastrin. In contrast, the IC50 for inhibition of cell growth with two benzodiazepine-derived antagonists, the CCK-B receptor antagonist L-365,260 (4.6 x 10(-5) M) and the CCK-A receptor antagonist devazepide (1.7 x 10(-5) M) were two-three orders of magnitude greater than those required to inhibit gastrin binding (10(-8)-10(-7) M). The growth inhibitory effects of L-365,260 and devazepide were not reversed by exogenous gastrin suggesting these benzodiazepine-derived antagonists do not inhibit cell growth by interaction with gastrin receptors. The results are consistent with gastrin being an autocrine growth factor in AR4-2J cells, and that stimulation of cell growth is due to stimulation of the gastrin, rather than CCK-B, receptor sub-type. This study highlights that gastrin receptor antagonists warrant further investigation as agents to control growth of tumours, such as those from the gastrointestinal tract, which express gastrin receptors.
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spelling pubmed-19779122009-09-10 Autocrine stimulation of growth of AR4-2J rat pancreatic tumour cells by gastrin. Blackmore, M. Hirst, B. H. Br J Cancer Research Article The control of cell proliferation by gastrin has been investigated in a rat pancreatic tumour cell line, AR4-2J. Exogenous gastrin, 10(-12) to 10(-8) M, stimulated cell growth of thymidine-synchronised AR4-2J cells cultured over 48 h in serum-free medium. Cell lysates of AR4-2J cells contained an average of 4.5 and 3.5 pg gastrin per 10(6) cells, when grown in serum-supplemented or serum-free media, respectively, as revealed by radioimmunoassay. In serum-free medium, AR4-2J secrete 34 ng 1(-1) 10(-6) cells of gastrin over 48 h. Addition of an anti-gastrin immunoglobulin preparation, but not control immunoglobulins, caused a maximum 52% reduction in cell growth. These data are consistent with an autocrine role for gastrin in the control of AR4-2J cell growth. These results were supported by studies with gastrin/CCK receptor antagonists. Six non-peptide gastrin/CCK receptor antagonists inhibited AR4-2J cell growth in a concentration-related manner. The concentration required for 50% inhibition (IC50) of cell growth by the amino acid-derived antagonists proglumide (3.5 x 10(-3) M), benzotript (1.8 x 10(-3) M), loxiglumide (1.1 x 10(-4) M) and lorglumide (6.7 x 10(-5) M) were of the same order and significantly correlated with their IC50 for inhibition of 125I-gastrin binding to AR4-2J cells. Inhibition of cell growth by these antagonists was partially reversed by the addition of exogenous gastrin. In contrast, the IC50 for inhibition of cell growth with two benzodiazepine-derived antagonists, the CCK-B receptor antagonist L-365,260 (4.6 x 10(-5) M) and the CCK-A receptor antagonist devazepide (1.7 x 10(-5) M) were two-three orders of magnitude greater than those required to inhibit gastrin binding (10(-8)-10(-7) M). The growth inhibitory effects of L-365,260 and devazepide were not reversed by exogenous gastrin suggesting these benzodiazepine-derived antagonists do not inhibit cell growth by interaction with gastrin receptors. The results are consistent with gastrin being an autocrine growth factor in AR4-2J cells, and that stimulation of cell growth is due to stimulation of the gastrin, rather than CCK-B, receptor sub-type. This study highlights that gastrin receptor antagonists warrant further investigation as agents to control growth of tumours, such as those from the gastrointestinal tract, which express gastrin receptors. Nature Publishing Group 1992-07 /pmc/articles/PMC1977912/ /pubmed/1637673 Text en https://creativecommons.org/licenses/by/4.0/This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit https://creativecommons.org/licenses/by/4.0/.
spellingShingle Research Article
Blackmore, M.
Hirst, B. H.
Autocrine stimulation of growth of AR4-2J rat pancreatic tumour cells by gastrin.
title Autocrine stimulation of growth of AR4-2J rat pancreatic tumour cells by gastrin.
title_full Autocrine stimulation of growth of AR4-2J rat pancreatic tumour cells by gastrin.
title_fullStr Autocrine stimulation of growth of AR4-2J rat pancreatic tumour cells by gastrin.
title_full_unstemmed Autocrine stimulation of growth of AR4-2J rat pancreatic tumour cells by gastrin.
title_short Autocrine stimulation of growth of AR4-2J rat pancreatic tumour cells by gastrin.
title_sort autocrine stimulation of growth of ar4-2j rat pancreatic tumour cells by gastrin.
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1977912/
https://www.ncbi.nlm.nih.gov/pubmed/1637673
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