Inhibition of growth and metastases of MDA-MB-435 human estrogen-independent breast cancers by an antagonist of growth hormone-releasing hormone.
Anticancer Drugs
; 12(9): 761-8, 2001 Oct.
Article
em En
| MEDLINE
| ID: mdl-11593058
ABSTRACT
Antagonists of growth hormone-releasing hormone (GH-RH) inhibit the growth of various cancers by mechanism(s) that include the suppression of the insulin-like growth factors (IGF)-I and/or -II. In this study, nude mice bearing orthotopic implants of MDA-MB-435 human estrogen-independent breast carcinoma received 39 days of therapy with GH-RH antagonist JV-1-36 (20 microg/day). The treatment significantly inhibited tumor growth by 71.1% (p<0.01) and nullified the metastatic potential of MDA-MB-435 cells. Four of eight control mice (50%) developed metastases in the lymph nodes and one (12.5%) in the lung, but none of the animals receiving JV-1-36 showed metastatic spread. GH-RH antagonist JV-1-36 inhibited the growth of MDA-MB-435 cells in vitro, while IGF-I stimulated it. However, mRNA for IGF-I or -II was not detected in MDA-MB-435 cells, indicating that the suppression of autocrine IGFs may not be involved in the antiproliferative mechanism. Using ligand competition assays with (125)I-labeled GH-RH antagonist JV-1-42, specific high-affinity binding sites for GH-RH were found on tumor membranes. Reverse transcription-polymerase chain reaction revealed the expression of mRNA for GH-RH receptor splice variant-1 in MDA-MB-435 tumors. Our results suggest that the antitumorigenic action of GH-RH antagonists on MDA-MB-435 breast cancer could be direct and mediated by tumoral GH-RH receptors.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Neoplasias da Mama
/
Hormônio Liberador de Hormônio do Crescimento
/
Antineoplásicos
Tipo de estudo:
Prognostic_studies
Limite:
Animals
/
Female
/
Humans
Idioma:
En
Revista:
Anticancer Drugs
Assunto da revista:
ANTINEOPLASICOS
Ano de publicação:
2001
Tipo de documento:
Article
País de afiliação:
Estados Unidos