Chou CF, et al. - The effectiveness and mechanism of action of 9-cis UAB30 (UAB30) in the treatment of cutaneous T-cell lymphomas (CTCLs) were assessed, and compared with bexarotene. Early cell apoptosis and cell proliferation suppression were shown to be induced by UAB30 and bexarotene. Inhibition of the G1 to S cell cycle transition by rexinoids was mediated through down-regulation of SKP2 and/or 20S proteasome activity, thereby leading to increased p27kip1 protein stability. UAB30 is a potentially better alternative to bexarotene for treatment of CTCLs.