title: Selective inhibition of the tumor marker AKR1B10 by antiinflammatory N-phenylanthranilic acids and glycyrrhetic acid.
abstract: A human aldose reductase-like protein, AKR1B10 in the aldo-keto reductase (AKR) superfamily, was recently identified as a tumor marker of several types of cancer. Tolrestat, an aldose reductase inhibitor (ARI), is known to be the most potent inhibitor of the enzyme. In this study, we compared the inhibitory effects of other ARIs including flavonoids on AKR1B10 and aldose reductase to evaluate their specificity. However, ARIs showed lower inhibitory potency for AKR1B10 than for aldose reductase. In the search for potent and selective inhibitors of AKR1B10 from other drugs used clinically, we found that non-steroidal antiinflammatory N-phenylanthranilic acids, diclofenac and glycyrrhetic acid competitively inhibited AKR1B10, showing K(i) values of 0.35-2.9 microM and high selectivity to this enzyme (43-57 fold versus aldose reductase). Molecular docking studies of mefenamic acid and glycyrrhetic acid in the AKR1B10-nicotinamide adenine dinucleotide phosphate (NADP(+)) complex and site-directed mutagenesis of the putative binding residues suggest that the side chain of Val301 and a hydrogen-bonding network among residues Val301, Gln114 and Ser304 are important for determining the inhibitory potency and selectivity of the non-steroidal antiinflammatory drugs. Thus, the potent and selective inhibition may be related to the cancer chemopreventive roles of the drugs, and their structural features may facilitate the design of new anti-cancer agents targeting AKR1B10.
authors.affiliation: Laboratory of Biochemistry, Gifu Pharmaceutical University, Daigaku-Nishi, Gifu 501-1196, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Endo
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Matsunaga
authors.forename: Midori
authors.initials: M
authors.lastname: Soda
authors.forename: Kazuo
authors.initials: K
authors.lastname: Tajima
authors.forename: Hi-Tai
authors.initials: HT
authors.lastname: Zhao
authors.forename: Ossama
authors.initials: O
authors.lastname: El-Kabbani
authors.forename: Akira
authors.initials: A
authors.lastname: Hara
mesh_terms: D000449:Aldehyde Reductase / Q000037:antagonists & inhibitors*; D000074408:Aldo-Keto Reductases; D000596:Amino Acids / Q000737:chemistry; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000737:chemistry / Q000494:pharmacology*; D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000494:pharmacology*; D014408:Biomarkers, Tumor / Q000037:antagonists & inhibitors*; D004008:Diclofenac / Q000737:chemistry / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology; D054361:Fenamates / Q000737:chemistry / Q000494:pharmacology*; D005419:Flavonoids / Q000737:chemistry / Q000494:pharmacology; D006034:Glycyrrhetinic Acid / Q000737:chemistry / Q000494:pharmacology*; D006801:Humans; D008528:Mefenamic Acid / Q000737:chemistry / Q000494:pharmacology; D009154:Mutation; D009249:NADP / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D013379:Substrate Specificity
chemical_list: D000596:Amino Acids; D000894:Anti-Inflammatory Agents, Non-Steroidal; D000972:Antineoplastic Agents, Phytogenic; D014408:Biomarkers, Tumor; D004791:Enzyme Inhibitors; D054361:Fenamates; D005419:Flavonoids; D010936:Plant Extracts; D004008:Diclofenac; D008528:Mefenamic Acid; D009249:NADP; C120471:AKR1B10 protein, human; D000074408:Aldo-Keto Reductases; D000449:Aldehyde Reductase; D006034:Glycyrrhetinic Acid