Selective release of a cyclopamine glucuronide prodrug toward stem-like cancer cell inhibition in glioblastoma.
Mol Cancer Ther
; 13(9): 2159-69, 2014 Sep.
Article
em En
| MEDLINE
| ID: mdl-25053823
ABSTRACT
Recent data suggest that inhibition of the Hedgehog pathway could be a therapeutic target for glioblastoma. Alkaloid cyclopamine inhibits Hedgehog signaling, depleting stem-like cancer cells derived from glioblastoma. However, this compound is toxic for somatic stem cells, preventing its use for clinical applications. In this study, we tested a derivatization product of cyclopamine in the form of cyclopamine glucuronide prodrug (CGP-2). This compound was used in vitro and in vivo toward glioblastoma-initiating cells (GIC). Results obtained in vitro indicate that CGP-2 is active only in the presence of ß-glucuronidase, an enzyme detected in high levels in necrotic areas of glioblastomas. CGP-2 decreased proliferation and inhibited the self-renewal of all GIC lines tested. Hedgehog pathway blockade by 10 µmol/L of CGP-2 induced a 99% inhibition of clonogenicity on GICs, similar to cyclopamine treatment. Combination of CGP-2 with radiation decreased clonogenic survival in all GIC lines compared with CGP-2 alone. In a subcutaneous glioblastoma xenograft model, a two-week CGP-2 treatment prevented tumor growth with 75% inhibition at 8 weeks, and this inhibition was still significant after 14 weeks. Unlike cyclopamine, CGP-2 had no detectable toxic effects in intestinal crypts. Our study suggests that inhibition of the Hedgehog pathway with CGP-2 is more effective than conventional temozolomide adjuvant, with much lower concentrations, and seems to be an effective therapeutic strategy for targeting GICs.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Células-Tronco Neoplásicas
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Alcaloides de Veratrum
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Pró-Fármacos
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Glioblastoma
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Glucuronídeos
Limite:
Animals
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Female
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Humans
Idioma:
En
Revista:
Mol Cancer Ther
Ano de publicação:
2014
Tipo de documento:
Article