Interleukin 4 down-regulates expression of c-kit and autocrine stem cell factor in human colorectal carcinoma cells.
Cell Growth Differ
; 6(9): 1111-8, 1995 Sep.
Article
en En
| MEDLINE
| ID: mdl-8519688
ABSTRACT
Stem cell factor (SCF) is a cytokine which plays an important role in the development of precursor cells. We have investigated the expression of SCF and its receptor, the c-kit proto-oncogene, in human colorectal carcinoma cell lines. Using reverse transcription-PCR, we confirmed the expression of c-kit in two lines (LS174T and LS1034) and of SCF in 9 of 11 cell lines tested. In a Northern blot, a single transcript of 6.6 kb was detected for SCF mRNA. In addition, two lines (LS174T and HT29) synthesized SCF protein, as detected by Western blot analysis. SCF stimulated proliferation and colony formation of LS174T in a dose-dependent manner up to 160%. A half-maximal effect was obtained with about 5.5 ng/ml of SCF under both growth conditions. LS174T cells expressed the M(r) 145,000 c-kit protein on the cell surface and a neutralizing anti-c-kit mAb inhibited colony formation of LS174T by 40%. Interleukin 4 (IL-4) completely inhibited SCF-induced proliferation of LS174T cells. Interestingly, IL-4 induced an almost complete down-regulation of both c-kit and SCF expression in LS174T. Our findings suggest that in LS174T cells, an SCF-mediated autocrine loop is functional and that IL-4 down-regulates the expression of both the receptor and the ligand of this circuit.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Proto-Oncogenes
/
Neoplasias Colorrectales
/
Regulación Neoplásica de la Expresión Génica
/
Interleucina-4
/
Factor de Células Madre
Límite:
Humans
Idioma:
En
Revista:
Cell Growth Differ
Asunto de la revista:
BIOLOGIA MOLECULAR
Año:
1995
Tipo del documento:
Article
País de afiliación:
Suiza