The hydrolyzed products of iridoid glycoside with ß-glucosidase treatment exert anti-proliferative effects through suppression of STAT3 activation and STAT3-regulated gene products in several human cancer cells.
Pharm Biol
; 50(1): 8-17, 2012 Jan.
Article
en En
| MEDLINE
| ID: mdl-22149883
ABSTRACT
CONTEXT Iridoids belong to a group of monoterpene compounds with cyclopentane ring and found as mostly the glycoside forms in nature. They act primarily as the defense substances and found in various medicinal plants. OBJECTIVE:
Although many iridoids exhibit anti-inflammatory and anticancer activities, their molecular targets/pathways are not fully understood. Here, the antiproliferative effect of the hydrolyzed-iridoid product (H-iridoid) form through the STAT3 signaling pathways on tumor cells was investigated. MATERIALS ANDMETHODS:
H-iridoids were obtained from five iridoid glycosides with ß-glucosidase treatment. The effects of several H-iridoids on cell viability and cell proliferation in tumor cells were measured by the MTT assay. The phosphorylation levels of STAT3, its regulatory molecules, and apoptosis by H-geniposide treatment in DU145 cells were investigated by immunoblots and flow cytometry.RESULTS:
No single iridoid glycoside exerted any cytotoxicity in the tumor cells, whereas H-iridoids had significant cytotoxic, antiproliferative, and STAT3 inhibitory effects and revealed different potencies depending on their chemical structures. Among the H-iridoids tested, H-geniposide inhibited constitutive STAT3 activation through inhibiting upstream JAK1 and c-Src. Consistent with STAT3 inactivation, H-geniposide downregulated the expressions of Bcl-2, Bcl-xL, survivin, and cyclin D1; this correlated with the accumulation of cells in the sub-G1 phase of the cell cycle and the induction of apoptosis. DISCUSSION ANDCONCLUSIONS:
Our results indicate that the hydrolysis of the glycosidic bond from iridoid glycoside is required for exhibiting cytotoxicity in tumor cells. H-geniposide is the most potent agent and a novel blocker of STAT3 activation in DU145 cells.
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Banco de datos:
MEDLINE
Asunto principal:
Regulación Neoplásica de la Expresión Génica
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Factor de Transcripción STAT3
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Glicósidos Iridoides
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Neoplasias
Límite:
Humans
Idioma:
En
Año:
2012
Tipo del documento:
Article