Local secretion of parathyroid hormone-related protein by an osteoblastic osteosarcoma (UMR 106-01) cell line results in growth inhibition.
Bone
; 31(5): 598-605, 2002 Nov.
Article
en En
| MEDLINE
| ID: mdl-12477574
ABSTRACT
Parathyroid hormone-related protein (PTHrP) has been implicated as being important in the growth of tumor cells responsive to the peptide. We utilized a rat osteoblastic osteosarcoma cell line, UMR 106-01, which has PTHrP receptors and a PTHrP-responsive adenylate cyclase/cAMP messenger system, to produce a modified cell line that overexpresses PTHrP. The human PTHrP cDNA sequence was transfected by electroporation into UMR 106-01 cells and the stable cell lines UMR-36 and UMR-34 were established. The modified cell line, UMR-36, had increased levels of PTHrP mRNA compared with control cell lines and secreted PTHrP into the culture medium at levels of 0.01-0.1 pmol/10(7) cells in 12 h. The secreted peptide was biologically active as indicated by its ability to activate adenylate cyclase. The number of UMR-36 cells following 9 days in culture was reduced by up to 80% compared with control lines, which was associated with decreased (3)H-thymidine incorporation into genomic DNA. Addition of 1000-fold excess of the PTHrP antagonist, PTHrP(7-34), to UMR-36 cells resulted in the escape of growth inhibition and increased rate of growth. In vivo, tumors derived from UMR-36 cells were smaller in size compared with tumors derived from control cells. In conclusion, increased autocrine secretion of, and responsiveness to, PTHrP results in inhibited growth kinetics of an osteoblast-like bone tumor cell line in vitro and in vivo.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Osteoblastos
/
Neoplasias Óseas
/
Osteosarcoma
/
Hormonas Peptídicas
/
Inhibidores de Crecimiento
Límite:
Animals
/
Female
/
Humans
Idioma:
En
Revista:
Bone
Asunto de la revista:
METABOLISMO
/
ORTOPEDIA
Año:
2002
Tipo del documento:
Article
País de afiliación:
Australia