Persistent inhibition of FLIP(L) expression by lentiviral small hairpin RNA delivery restores death-receptor-induced apoptosis in neuroblastoma cells.
Neuroblastoma represents the most common and deadly solid tumour of childhood, which disparate biological and clinical behaviour can be explained by differential regulation of apoptosis. To understand mechanisms underlying death resistance in neuroblastoma cells, we developed small hairpin of RNA produced by lentiviral vectors as tools to selectively interfere with FLIP(L), a major negative regulator of death receptor-induced apoptosis. Such tools revealed highly efficient in interfering with FLIP(L) expression and function as they almost completely repressed endogenous and/or exogenously overexpressed FLIP(L) protein and fully reversed FLIP(L)-mediated TRAIL resistance. Moreover, interference with endogenous FLIP(L) and FLIP(S) significantly restored FasL sensitivity in SH-EP neuroblastoma cell line. These results reveal the ability of lentivirus-mediated shRNAs to specifically and persistently interfere with FLIP expression and support involvement of FLIP in the regulation of death receptor-mediated apoptosis in neuroblastoma cells. Combining such tools with other therapeutic modalities may improve treatment of resistant tumours such as neuroblastoma.
Flahaut
M
M
Paediatric Oncology Research, Paediatric Department, University Hospital CHUV, CH-1011, Lausanne.
Mühlethaler-Mottet
A
A
Auderset
K
K
Bourloud
K Balmas
KB
Meier
R
R
Popovic
M Beck
MB
Joseph
J M
JM
Gross
N
N
D017209:Apoptosis / Q000235:genetics*; D051017:Apoptosis Regulatory Proteins / Q000494:pharmacology*; D053446:CASP8 and FADD-Like Apoptosis Regulating Protein; D002460:Cell Line; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D005822:Genetic Vectors; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000037:antagonists & inhibitors*; D016086:Lentivirus / Q000235:genetics; D008562:Membrane Glycoproteins / Q000494:pharmacology*; D008957:Models, Genetic; D009447:Neuroblastoma / Q000473:pathology*; D034741:RNA, Small Interfering / Q000378:metabolism* / Q000494:pharmacology; D053221:TNF-Related Apoptosis-Inducing Ligand; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
D051017:Apoptosis Regulatory Proteins; D053446:CASP8 and FADD-Like Apoptosis Regulating Protein; C506386:CFLAR protein, human; D047908:Intracellular Signaling Peptides and Proteins; D008562:Membrane Glycoproteins; D034741:RNA, Small Interfering; D053221:TNF-Related Apoptosis-Inducing Ligand; C505653:TNFSF10 protein, human; D014409:Tumor Necrosis Factor-alpha