title: Mechanisms of enhancement of TRAIL tumoricidal activity against human cancer cells of different origin by dipyridamole.
abstract: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has emerged as an attractive cytokine that selectively targets cancer cells, however its efficacy has been challenged by a number of resistance mechanisms. Therefore, the current study investigated the potential of dipyridamole to enhance TRAIL efficacy and the probable underlying mechanisms. Dipyridamole dramatically sensitized p53-mutant human cancer cell lines: SW480, MG63 and DU145, to the antitumor activity of TRAIL, as evidenced by enabling TRAIL to efficiently cleave initiator and executioner caspases. Although dipyridamole upregulated both DR4 and DR5 and increased their cell surface expression, RNA interference revealed a preferential dependence on DR5. Moreover, dipyridamole inhibited survivin expression and its important consequences were confirmed by small interfering RNA. Mechanistically, dipyridamole induced transcriptional shutdown of survivin expression accompanying G(1) arrest that was characterized by downregulation of D-type cyclins and cdk6. In addition, a transcriptional mechanism powered by CCAAT/enhancer-binding protein (C/EBP) homologous protein (CHOP) induction was responsible for DR5 upregulation by dipyridamole. Importantly, dipyridamole-induced enhancement of TRAIL efficacy and alterations of protein expression were independent of either protein kinase A or protein kinase G. In conclusion, findings of the present study described novel mechanisms of dipyridamole action and highlighted its promising use as a potential enhancer of TRAIL efficacy.
authors.affiliation: Department of Molecular-Targeting Cancer Prevention, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: A E
authors.initials: AE
authors.lastname: Goda
authors.forename: T
authors.initials: T
authors.lastname: Yoshida
authors.forename: M
authors.initials: M
authors.lastname: Horinaka
authors.forename: T
authors.initials: T
authors.lastname: Yasuda
authors.forename: T
authors.initials: T
authors.lastname: Shiraishi
authors.forename: M
authors.initials: M
authors.lastname: Wakada
authors.forename: T
authors.initials: T
authors.lastname: Sakai
mesh_terms: D017209:Apoptosis / Q000187:drug effects* / Q000502:physiology; D015152:Blotting, Northern; D001859:Bone Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D003110:Colonic Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D017868:Cyclic AMP-Dependent Protein Kinases / Q000235:genetics / Q000378:metabolism; D017869:Cyclic GMP-Dependent Protein Kinases / Q000235:genetics / Q000378:metabolism; D004176:Dipyridamole / Q000494:pharmacology*; D016193:G1 Phase / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D015151:Immunoblotting; D051034:Inhibitor of Apoptosis Proteins; D008156:Luciferases / Q000378:metabolism; D008297:Male; D008869:Microtubule-Associated Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D009154:Mutation / Q000235:genetics; D009363:Neoplasm Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D009369:Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology*; D012516:Osteosarcoma / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology*; D011471:Prostatic Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D034741:RNA, Small Interfering / Q000494:pharmacology; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D018124:Receptors, Tumor Necrosis Factor / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D000077022:Survivin; D053221:TNF-Related Apoptosis-Inducing Ligand / Q000378:metabolism*; D051742:Transcription Factor CHOP / Q000235:genetics / Q000378:metabolism; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism
chemical_list: C107489:BIRC5 protein, human; C497249:DDIT3 protein, human; D051034:Inhibitor of Apoptosis Proteins; D008869:Microtubule-Associated Proteins; D009363:Neoplasm Proteins; D010726:Phosphodiesterase Inhibitors; D034741:RNA, Small Interfering; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand; D018124:Receptors, Tumor Necrosis Factor; D000077022:Survivin; D053221:TNF-Related Apoptosis-Inducing Ligand; C105190:TNFRSF10A protein, human; C505653:TNFSF10 protein, human; D014409:Tumor Necrosis Factor-alpha; D016159:Tumor Suppressor Protein p53; D051742:Transcription Factor CHOP; D004176:Dipyridamole; D008156:Luciferases; D017868:Cyclic AMP-Dependent Protein Kinases; D017869:Cyclic GMP-Dependent Protein Kinases