The protooncogene c-myb increases the expression of insulin-like growth factor 1 and insulin-like growth factor 1 receptor messenger RNAs by a transcriptional mechanism.
Cancer Res
; 51(21): 5997-6000, 1991 Nov 01.
Article
em En
| MEDLINE
| ID: mdl-1657376
ABSTRACT
The protooncogene c-myb is the cellular equivalent of the viral transforming oncogene v-myb. When human c-myb is constitutively expressed in Balb/c3T3 cells it abrogates their absolute requirement for insulin-like growth factor 1 (IGF-1). We show now, in two different cell lines, that the constitutive expression of the protooncogene c-myb causes an increase in both IGF-1 and IGF = 1 receptor mRNA levels. This increase in mRNA levels is due, at least in part, to an increase in the rate of transcription since, by run-on assay, cells carrying the human c-myb cDNA show a 3-fold increase in transcriptional rates in comparison to the control parent cell lines. The increased expression of IGF-1 receptor mRNA also results in an increased number of IGF-1 binding sites per cell. Although some oncogenes have been described that are homologous to growth factors, or growth factor receptors, c-myb seems to represent a novel way of oncogene action inasmuch as it increases the expression of both a growth factor receptor and its ligand, thus establishing a quasi-autocrine mechanism which modifies the growth factor requirements of the cell and its growth regulation.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oncogenes
/
Transcrição Gênica
/
Proto-Oncogenes
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RNA Mensageiro
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Fator de Crescimento Insulin-Like I
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Transfecção
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Regulação Neoplásica da Expressão Gênica
/
Receptores de Superfície Celular
Limite:
Animals
/
Humans
Idioma:
En
Revista:
Cancer Res
Ano de publicação:
1991
Tipo de documento:
Article