Apoptosis-induced by TRAIL AND TNF-alpha in human multiple myeloma cells is not blocked by BCL-2.
TRAIL, the ligand for the newly discovered DR-4 and DR-5 receptor is a member of the tumour necrosis factor (TNF) family of death signal tranduction proteins with a mechanism of cell death, similar to the Fas and Fas ligand (Fas-L) system. Here, we provide first time evidence that TRAIL and TNF-alpha are potent inducers of apoptosis in multiple myeloma (MM) cell lines and freshly isolated myeloma cells. TRAIL effectively induced extensive apoptosis in 8226 and ARP-1 MM cells in a time- and dose-dependent manner reaching 80% within 48 h of treatment with a dose of 160 ng/ml. Bcl-2 transfected 8226 and ARP-1 cells were equally sensitive to apoptosis by TRAIL. Apoptosis with TNFalpha, reached >60% within 48 h of treatment with a dose of 160 ng/ml. In addition to MM cell lines, freshly isolated, flow-sorted myeloma cells from 8 different MM patients expressing variable levels of bcl-2 were equally sensitive to both TRAIL and TNF-alpha. We have previously shown that anti-Fas-induced apoptosis is not blocked by endogenous or ectopic bcl-2 in MM cell lines. Here we extend our observation with Fas to include TNF-alpha and TRAIL to the apoptotic signals that are not be blocked by bcl-2, in MM cells.
Gazitt
Y
Y
Department of Medicine/Hematology, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, U S A.
Shaughnessy
P
P
Montgomery
W
W
D017209:Apoptosis / Q000187:drug effects*; D051017:Apoptosis Regulatory Proteins; D006801:Humans; D008024:Ligands; D008562:Membrane Glycoproteins / Q000378:metabolism* / Q000494:pharmacology; D009101:Multiple Myeloma / Q000378:metabolism / Q000473:pathology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis*; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand; D018124:Receptors, Tumor Necrosis Factor / Q000378:metabolism; D053221:TNF-Related Apoptosis-Inducing Ligand; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism* / Q000494:pharmacology
D051017:Apoptosis Regulatory Proteins; D008024:Ligands; D008562:Membrane Glycoproteins; D019253:Proto-Oncogene Proteins c-bcl-2; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand; D018124:Receptors, Tumor Necrosis Factor; D053221:TNF-Related Apoptosis-Inducing Ligand; C105190:TNFRSF10A protein, human; C505639:TNFRSF10B protein, human; C505653:TNFSF10 protein, human; D014409:Tumor Necrosis Factor-alpha