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Updated: Jul 6, 2026

Chemical Inactivation of the E3 Ubiquitin Ligase Cereblon by Pomalidomide-based Homo-PROTACs
Published on: May 15, 2019
Cationic polyrotaxanes effectively inhibit uptake via carnitine/organic cationic transporters without cytotoxicity
Hideto Utsunomiya1, Ryo Katoono, Nobuhiko Yui
1School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923-1292, Japan.
Abstract:
We examined the inhibitory effect of cationic polyrotaxanes, which consist of alpha-cyclodextrins threaded on a poly(ethylene glycol) (PEG) chain, on the activity of the intestinal carnitine/organic cation transporter, OCTN2, in OCTN2 gene-transfected HEK293/PDZK1 cells. The cationic polyrotaxanes effectively inhibited the OCTN2-mediated carnitine transport. Polyrotaxanes with a longer PEG chain exhibited a greater inhibitory effect, possibly owing to multivalent interactions with binding sites on OCTN2. These cationic polyrotaxanes were far less cytotoxic than conventional polycations, and are therefore interesting candidates as low-toxicity inhibitors of cation transport at cell surfaces.
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