title: Acyl-CoA synthetase as a cancer survival factor: its inhibition enhances the efficacy of etoposide.
abstract: Lipid metabolism is often elevated in cancer cells and plays an important role in their growth and malignancy. Acyl-CoA synthetase (ACS), which converts long-chain fatty acids to acyl-CoA, is overexpressed in various types of cancer. However, the role of ACS in cancer remains unknown. Here, we found that ACS enzyme activity is required for cancer cell survival. Namely, the ACS inhibitor Triacsin c induced massive apoptosis in glioma cells while this cell death was completely suppressed by overexpression of ACSL5, the Triacsin c-resistant ACS isozyme, but not by overexpression of a catalytically inactive ACSL5 mutant. ACS inhibition by Triacsin c markedly potentiated the Bax-induced intrinsic apoptotic pathway by promoting cytochrome c release and subsequent caspase activation. These effects were abrogated by ACSL5 overexpression. Correspondingly, ACS inhibition synergistically potentiated the glioma cell death induced by etoposide, a well-known activator of apoptosis. Furthermore, in a nude mouse xenograft model, Triacsin c at a non-toxic dose enhanced the antitumor efficacy of a low-dose chemotherapy with etoposide. These results indicate that ACS is an apoptosis suppressor and that ACS inhibition could be a rational strategy to amplify the antitumor effect of etoposide.
authors.affiliation: Division of Molecular Biotherapy, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, Koto-ku, Tokyo, Japan.
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Mashima
authors.forename: Shigeo
authors.initials: S
authors.lastname: Sato
authors.forename: Sachiko
authors.initials: S
authors.lastname: Okabe
authors.forename: Satoshi
authors.initials: S
authors.lastname: Miyata
authors.forename: Masaaki
authors.initials: M
authors.lastname: Matsuura
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Sugimoto
authors.forename: Takashi
authors.initials: T
authors.lastname: Tsuruo
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Seimiya
mesh_terms: D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D001562:Benzimidazoles / Q000378:metabolism; D020169:Caspases / Q000032:analysis; D002384:Catalysis; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D003066:Coenzyme A Ligases / Q000037:antagonists & inhibitors*; D003574:Cytochrome c Group / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005047:Etoposide / Q000494:pharmacology*; D005455:Fluorescent Antibody Technique; D005456:Fluorescent Dyes / Q000378:metabolism; D005910:Glioma / Q000235:genetics / Q000473:pathology*; D006801:Humans; D007211:Indoles / Q000378:metabolism; D007279:Injections, Subcutaneous; D007527:Isoenzymes / Q000037:antagonists & inhibitors; D051379:Mice; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D013347:Subcellular Fractions; D013778:Tetrazolium Salts / Q000378:metabolism; D013844:Thiazoles / Q000378:metabolism; D014226:Triazenes / Q000494:pharmacology*; D047368:Tumor Burden; D023041:Xenograft Model Antitumor Assays; D000098859:Long-Chain-Fatty-Acid-CoA Ligase
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D001562:Benzimidazoles; D003574:Cytochrome c Group; D005456:Fluorescent Dyes; D007211:Indoles; D007527:Isoenzymes; D013778:Tetrazolium Salts; D013844:Thiazoles; D014226:Triazenes; C076615:cytochrome c''; C070380:3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium; C007293:DAPI; C034613:triacsin C; D005047:Etoposide; D020169:Caspases; D003066:Coenzyme A Ligases; D000098859:Long-Chain-Fatty-Acid-CoA Ligase; C017807:bisbenzimide ethoxide trihydrochloride