RARA and hyperlipidemia: These side effects arise because, much like 9-cis-RA, bexarotene (1) disrupts nonpermissive heterodimers—such as TR-RXR to incite hypothyroidism [35]—and concurrently stimulates permissive heterodimers—such as LXR-RXR to provoke hyperlipidemia [36,37] or cutaneous toxicity [38] via activating RAR at raised dose concentrations.