TY - JOUR
T1 - Phosphatidylinositol 3-Kinase Inhibition Down-Regulates Survivin and Facilitates TRAIL-Mediated Apoptosis in Neuroblastomas
AU - Kim, Sunghoon
AU - Kang, Junghee
AU - Qiao, Jingbo
AU - Thomas, Robert P.
AU - Evers, B. Mark
AU - Chung, Dai H.
N1 - Funding Information:
Supported by grants RO1DK61470, RO1DK48498, PO1DK35608, and T32DK07639 from the National Institutes of Health and by an American Cancer Society Institutional Grant (#2002-01).
PY - 2004/4
Y1 - 2004/4
N2 - Background/Purpose: Recent findings have correlated neuroblastoma development with aberration of apoptosis. In particular, increased levels of survivin, a member of the inhibitor of apoptosis protein (IAP) family, have been associated with increased resistance to apoptosis in neuroblastomas. The purpose of this study was to determine whether the phosphatidylinositol 3-kinase (PI3K)/Akt pathway can alter the expression of survivin and facilitate tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis in neuroblastoma cells. Methods: Human neuroblastoma cells (SK-N-SH, BE[2]C, LAN-1 and IMR-32) were treated with LY294002 or wortmannin, inhibitors of PI3K, for 24 hours. Transient transfection of a dominant negative PI3K expression plasmid, pCGNN-Δp85, was performed to inhibit PI3K activation. Cells were treated with TRAIL, caspase-3, or pan-caspase inhibitors. RNase protection assay was performed to assess mRNA changes in IAP family members, including survivin. Western blot analysis was performed to measure changes in the levels of procaspases and survivin. Apoptosis was assessed by a DNA fragmentation ELISA assay. Results: The authors found that survivin and cIAP1 mRNA as well as protein expression were decreased after PI3K inhibition. Combination treatment with LY294002 and TRAIL increased apoptosis of SK-N-SH cells compared with TRAIL alone; these results were further corroborated by complete inhibition of apoptosis by caspase-3 or pan-caspase inhibitor. Conclusions: The authors report that PI3K pathway inhibition down-regulates survivin expression and enhances TRAIL-mediated apoptosis in neuroblastomas. PI3K pathway may play a crucial role in neuroblastoma cell survival; therefore, treatment with inhibitors of PI3K may provide potential novel therapeutic options.
AB - Background/Purpose: Recent findings have correlated neuroblastoma development with aberration of apoptosis. In particular, increased levels of survivin, a member of the inhibitor of apoptosis protein (IAP) family, have been associated with increased resistance to apoptosis in neuroblastomas. The purpose of this study was to determine whether the phosphatidylinositol 3-kinase (PI3K)/Akt pathway can alter the expression of survivin and facilitate tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis in neuroblastoma cells. Methods: Human neuroblastoma cells (SK-N-SH, BE[2]C, LAN-1 and IMR-32) were treated with LY294002 or wortmannin, inhibitors of PI3K, for 24 hours. Transient transfection of a dominant negative PI3K expression plasmid, pCGNN-Δp85, was performed to inhibit PI3K activation. Cells were treated with TRAIL, caspase-3, or pan-caspase inhibitors. RNase protection assay was performed to assess mRNA changes in IAP family members, including survivin. Western blot analysis was performed to measure changes in the levels of procaspases and survivin. Apoptosis was assessed by a DNA fragmentation ELISA assay. Results: The authors found that survivin and cIAP1 mRNA as well as protein expression were decreased after PI3K inhibition. Combination treatment with LY294002 and TRAIL increased apoptosis of SK-N-SH cells compared with TRAIL alone; these results were further corroborated by complete inhibition of apoptosis by caspase-3 or pan-caspase inhibitor. Conclusions: The authors report that PI3K pathway inhibition down-regulates survivin expression and enhances TRAIL-mediated apoptosis in neuroblastomas. PI3K pathway may play a crucial role in neuroblastoma cell survival; therefore, treatment with inhibitors of PI3K may provide potential novel therapeutic options.
KW - Neuroblastoma
KW - PI3K
KW - Survivin
KW - Tumor necrosis factor-related apoptosis-inducing ligand
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U2 - 10.1016/j.jpedsurg.2003.12.008
DO - 10.1016/j.jpedsurg.2003.12.008
M3 - Article
C2 - 15065019
AN - SCOPUS:16544395058
SN - 0022-3468
VL - 39
SP - 516
EP - 521
JO - Journal of Pediatric Surgery
JF - Journal of Pediatric Surgery
IS - 4
ER -