Sensitivity of Ewing's sarcoma to TRAIL-induced apoptosis.
Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is able to kill transformed cells. We have studied the expression and functionality of the TRAIL apoptotic pathway in Ewing's sarcoma. We demonstrate that tumors from patients with Ewing's sarcoma express receptors TRAIL-R1 and -R2. Using a panel of nine Ewing's sarcoma cell lines TRAIL could induce apoptosis in seven cell lines. Preincubation with interferon-gamma rendered the two resistant cell lines sensitive. TRAIL was the most potent inducer of apoptosis when compared to Fas ligand or TNF. TRAIL-mediated apoptosis could be inhibited by various caspase-inhibitors. No difference in the surface expression of TRAIL-receptors was observed between sensitive and resistant cell lines. Also, all cell lines had similar levels of expression of Flice-like inhibitory protein (FLIP) on immunoblot. However, the two resistant cell lines had only very low level expression of caspase 8 on RNA and protein level. In summary, we show that Ewing's sarcoma expresses receptors for TRAIL, and that cells are exquisitely sensitive to TRAIL-mediated apoptosis. These results may warrant clinical trials with TRAIL in Ewing's sarcoma once the safety of TRAIL for humans has been established.
Kontny
H U
HU
Children's Hospital of the Albert-Ludwigs-University, Freiburg, Germany.
Hämmerle
K
K
Klein
R
R
Shayan
P
P
Mackall
C L
CL
Niemeyer
C M
CM
D017209:Apoptosis / Q000187:drug effects*; D051017:Apoptosis Regulatory Proteins; D053446:CASP8 and FADD-Like Apoptosis Regulating Protein; D002352:Carrier Proteins / Q000235:genetics; D053181:Caspase 8; D053453:Caspase 9; D061945:Caspase Inhibitors; D020169:Caspases / Q000235:genetics / Q000378:metabolism; D003513:Cycloheximide / Q000494:pharmacology; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D004351:Drug Resistance; D005434:Flow Cytometry; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology; D047908:Intracellular Signaling Peptides and Proteins; D008562:Membrane Glycoproteins / Q000494:pharmacology*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D018124:Receptors, Tumor Necrosis Factor / Q000235:genetics / Q000378:metabolism; D012512:Sarcoma, Ewing / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D015398:Signal Transduction / Q000187:drug effects; D053221:TNF-Related Apoptosis-Inducing Ligand; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D019014:fas Receptor / Q000378:metabolism
D051017:Apoptosis Regulatory Proteins; D053446:CASP8 and FADD-Like Apoptosis Regulating Protein; C506386:CFLAR protein, human; D002352:Carrier Proteins; D061945:Caspase Inhibitors; D015853:Cysteine Proteinase Inhibitors; D047908:Intracellular Signaling Peptides and Proteins; D008562:Membrane Glycoproteins; D012333:RNA, Messenger; D018124:Receptors, Tumor Necrosis Factor; D053221:TNF-Related Apoptosis-Inducing Ligand; C505653:TNFSF10 protein, human; D014409:Tumor Necrosis Factor-alpha; D019014:fas Receptor; D007371:Interferon-gamma; D003513:Cycloheximide; C505530:CASP8 protein, human; C506433:CASP9 protein, human; D053181:Caspase 8; D053453:Caspase 9; D020169:Caspases