In:
Cancer Research, American Association for Cancer Research (AACR), Vol. 70, No. 8_Supplement ( 2010-04-15), p. 5382-5382
Abstract:
Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a member of the TNF family, which induces apoptosis in tumor cells while not in normal cells. TRAIL binds with two types of receptors which are apoptosis-inducing death receptors (TRAIL-R1 and TRAIL-R2) and non-apoptosis-inducing decoy receptors (TRAIL-R3 and TRAIL-R4). TRAIL has been considered as a promising agent for selective cancer therapy, although some cancer cells show resistance to apoptosis induction by this ligand. In this study, we examined whether combination treatment of chemotherapeutic drugs with TRAIL induces synergistic cell death in neuroblastoma cells. We showed that pre-treatment with sublethal concentrations of etoposide followed by exposure to TRAIL synergistically enhanced apoptotic cell death compared to treatment with etoposide or TRAIL alone in SK-N-MC cells (28 ± 2% versus 12 ± 3% or 2 ± 2% apoptotic cell death in 48 h), while not in IMR-32 cells (26 ± 4% versus 26 ± 7% or 0.5 ± 0.6% apoptotic cell death in 48 h). These synergistic cell death was inhibited by addition of fusion chimera protein (recombinant human TRAIL-R2: Fc), which can block TRAIL binding to TRAIL-R1 or TRAIL-R2. In addition, pre-treatment with sublethal concentrations of etoposide in SK-N-MC cells induced degradation of IκBα, resulting in NF-κB activation and up-regulation of TRAIL-R2 expression. The increase of TRAIL-R2 expression resulted in TRAIL-induced synergistic cell deaths, which were effectively inhibited by exposure to NF-κB inhibitor. Moreover, we showed that combination treatment significantly decreased the Mcl-1 expression and increased caspase-3 activation compared to treatment with etoposide or TRAIL alone. Our data suggest that pre-treated etoposide activates NF-κB by down-regulation of IκBα, and then NF-κB up-regulates TRAIL-R2 expression enhancing TRAIL-induced apoptosis in neuroblastoma cells. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5382.
Type of Medium:
Online Resource
ISSN:
0008-5472
,
1538-7445
DOI:
10.1158/1538-7445.AM10-5382
Language:
English
Publisher:
American Association for Cancer Research (AACR)
Publication Date:
2010
detail.hit.zdb_id:
2036785-5
detail.hit.zdb_id:
1432-1
detail.hit.zdb_id:
410466-3
Permalink