title: Pre-clinical assessment of A-674563 as an anti-melanoma agent.
abstract: The present study aims to investigate the anti-melanoma activity by an Akt1 specific inhibitor A-674563. We showed that A-674563 was anti-proliferative and cytotoxic when added to human melanoma cells (A375, WM-115 and SK-Mel-2 lines). A-674563 induced caspase-dependent apoptotic death of human melanoma cells, and its cytotoxicity was inhibited with pre-treatment of caspase inhibitors. Further, A-674563 treatment blocked Akt and its downstream S6 Kinase 1 (S6K1) activation in A375 melanoma cells. Significantly, restoring Akt-S6K1 activation via introduction of constitutively-active Akt1 (ca-Akt1) only partially attenuated A-674563's cytotoxicity against A375 cells. Further, A-674563 induced pro-apoptotic ceramide production in A375 cells. Significantly, sphingosine-1-phosphate (S1P) inhibited A-674563-induced ceramide production and subsequent A375 cell apoptosis. On the other hand, co-treatment with the glucosylceramide synthase (GCS) inhibitor PDMP or the cell permeable short-chain ceramide (C6) potentiated A-674563's cytotoxicity against A375 cells. In vivo, A-674563 oral gavage inhibited A375 xenograft growth in severe combined immunodeficiency (scid) mice. Akt inactivation, caspase-3 activation and ceramide production were also observed in A-674563-treated A375 xenografts. Together, these results suggest that A-674563 exerts potent anti-melanoma activity, involving Akt-dependent and Akt-independent mechanisms.
authors.affiliation: Skin & Cosmetic Research Department, Shanghai Skin Disease Hospital, Shanghai, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zou
authors.affiliation: Skin & Cosmetic Research Department, Shanghai Skin Disease Hospital, Shanghai, China.
authors.forename: Guobiao
authors.initials: G
authors.lastname: Fan
authors.affiliation: Skin & Cosmetic Research Department, Shanghai Skin Disease Hospital, Shanghai, China. Electronic address: wangxuemeidr@yeah.net.
authors.forename: Xuemin
authors.initials: X
authors.lastname: Wang
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology* / Q000627:therapeutic use; D017209:Apoptosis / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D004354:Drug Screening Assays, Antitumor; D004789:Enzyme Activation; D006801:Humans; D007191:Indazoles / Q000494:pharmacology* / Q000627:therapeutic use; D008545:Melanoma / Q000188:drug therapy*; D051379:Mice; D016513:Mice, SCID; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D011725:Pyridines / Q000494:pharmacology* / Q000627:therapeutic use; D023041:Xenograft Model Antitumor Assays
chemical_list: C000619514:A-674563; D000970:Antineoplastic Agents; D015853:Cysteine Proteinase Inhibitors; D007191:Indazoles; D011725:Pyridines; D051057:Proto-Oncogene Proteins c-akt
keywords: A-674563; Akt; Apoptosis; Ceramide; Melanoma