20-O-ß-d-glucopyranosyl-20(S)-protopanaxadiol, a metabolite of ginseng, inhibits colon cancer growth by targeting TRPC channel-mediated calcium influx.
J Nutr Biochem
; 24(6): 1096-104, 2013 Jun.
Article
en En
| MEDLINE
| ID: mdl-23318138
ABSTRACT
Abnormal regulation of Ca(2+) mediates tumorigenesis and Ca(2+) channels are reportedly deregulated in cancers, indicating that regulating Ca(2+) signaling in cancer cells is considered as a promising strategy to treat cancer. However, little is known regarding the mechanism by which Ca(2+) affects cancer cell death. Here, we show that 20-O-ß-d-glucopyranosyl-20(S)-protopanaxadiol (20-GPPD), a metabolite of ginseng saponin, causes apoptosis of colon cancer cells through the induction of cytoplasmic Ca(2+). 20-GPPD decreased cell viability, increased annexin V-positive early apoptosis and induced sub-G1 accumulation and nuclear condensation of CT-26 murine colon cancer cells. Although 20-GPPD-induced activation of AMP-activated protein kinase (AMPK) played a key role in the apoptotic death of CT-26 cells, LKB1, a well-known upstream kinase of AMPK, was not involved in this activation. To identify the upstream target of 20-GPPD for activating AMPK, we examined the effect of Ca(2+) on apoptosis of CT-26 cells. A calcium chelator recovered 20-GPPD-induced AMPK phosphorylation and CT-26 cell death. Confocal microscopy showed that 20-GPPD increased Ca(2+) entry into CT-26 cells, whereas a transient receptor potential canonical (TRPC) blocker suppressed Ca(2+) entry. When cells were treated with a TRPC blocker plus an endoplasmic reticulum (ER) calcium blocker, 20-GPPD-induced calcium influx was completely inhibited, suggesting that the ER calcium store, as well as TRPC, was involved. In vivo mouse CT-26 allografts showed that 20-GPPD significantly suppressed tumor growth, volume and weight in a dose-dependent manner. Collectively, 20-GPPD exerts potent anticarcinogenic effects on colon carcinogenesis by increasing Ca(2+) influx, mainly through TRPC channels, and by targeting AMPK.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Calcio
/
Neoplasias del Colon
/
Ginsenósidos
/
Canales Catiónicos TRPC
/
Panax
/
Antineoplásicos
Tipo de estudio:
Prognostic_studies
Límite:
Animals
Idioma:
En
Revista:
J Nutr Biochem
Asunto de la revista:
BIOQUIMICA
/
CIENCIAS DA NUTRICAO
Año:
2013
Tipo del documento:
Article