title: Tumor necrosis factor-related apoptosis-inducing ligand and chemotherapy cooperate to induce apoptosis in mesothelioma cell lines.
abstract: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) can induce apoptosis in certain tumor cells. In addition, TRAIL and chemotherapy can act cooperatively, possibly as a result of chemotherapy-induced increases in expression of a TRAIL receptor, DR5. We used cell lines derived from a highly chemoresistant tumor, malignant mesothelioma, to learn whether TRAIL was effective alone or together with chemotherapy and whether cooperativity depended on increases in DR5 expression. TRAIL (codons 95-285) was expressed in a bacterial expression vector and purified by nickel affinity chromatography. TRAIL alone (25 to 500 ng/ml) had little effect on mesothelioma cells. TRAIL plus chemotherapy (doxorubicin, cis-platinum, etoposide, or gemcitabine) acted cooperatively to induce apoptosis in mesothelioma cells (M28, REN, VAMT, and MS-1). For example, in M28 cells treated for 18 h, apoptosis from TRAIL (100 ng/ml) plus doxorubicin (0.6 microg/ml; 71 +/- 11%) greatly exceeded that from TRAIL alone (21 +/- 8%) or from doxorubicin alone (6 +/- 2%) (means +/- standard deviation; P < 0.03). Mesothelioma cells treated with chemotherapy showed no change in DR5 protein by Western analysis or by immunocytochemistry. TRAIL plus chemotherapy was associated with an increase in mitochondrial cytochrome c release and mitochondrial depolarization. We conclude that TRAIL and chemotherapy act cooperatively to kill mesothelioma cell lines, not by increases in DR5 receptor but in association with mitochondrial amplification of apoptotic signals.
authors.affiliation: Lung Biology Center, San Francisco General Hospital, University of California-San Francisco, San Francisco, CA 94143, USA.
authors.forename: W
authors.initials: W
authors.lastname: Liu
authors.forename: E
authors.initials: E
authors.lastname: Bodle
authors.forename: J Y
authors.initials: JY
authors.lastname: Chen
authors.forename: M
authors.initials: M
authors.lastname: Gao
authors.forename: G D
authors.initials: GD
authors.lastname: Rosen
authors.forename: V C
authors.initials: VC
authors.lastname: Broaddus
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects* / Q000502:physiology*; D051017:Apoptosis Regulatory Proteins; D001483:Base Sequence; D002945:Cisplatin / Q000494:pharmacology; D003574:Cytochrome c Group / Q000378:metabolism; D017931:DNA Primers; D004317:Doxorubicin / Q000494:pharmacology; D006367:HeLa Cells; D006801:Humans; D007150:Immunohistochemistry; D008562:Membrane Glycoproteins / Q000502:physiology*; D008654:Mesothelioma / Q000201:enzymology / Q000473:pathology*; D008928:Mitochondria / Q000201:enzymology; 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 / Q000502:physiology*
chemical_list: D000970:Antineoplastic Agents; D051017:Apoptosis Regulatory Proteins; D003574:Cytochrome c Group; D017931:DNA Primers; D008562:Membrane Glycoproteins; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand; D018124:Receptors, Tumor Necrosis Factor; D053221:TNF-Related Apoptosis-Inducing Ligand; C505639:TNFRSF10B protein, human; C505653:TNFSF10 protein, human; D014409:Tumor Necrosis Factor-alpha; D004317:Doxorubicin; D002945:Cisplatin