RA190

RA190, a bis-benzylidine piperidon, inhibits proteasome function by covalently binding to cysteine 88 of ubiquitin receptor RPN13. IC50 & Target: IC50: 0.15 μM (HeLa cell) In Vitro: RA190 covalently binds to cysteine 88 of ubiquitin receptor RPN13 in the 19S regulatory particle and inhibits proteasome function, triggering rapid accumulation of polyubiquitinated proteins. Multiple myeloma (MM) lines, even those resistant to bortezomib, are sensitive to RA190 via endoplasmic reticulum stress-related apoptosis. RA190 stabilizes targets of human papillomavirus (HPV) E6 oncoprotein, and preferentially kills HPV-transformed cells^[1]. In Vivo: RA190 distributes to plasma and major organs excepting brain, and inhibits proteasome function in skin and muscle. RA190 administration profoundly reduces growth of multiple myeloma and ovarian cancer xenografts, and oral RA190 treatment retards HPV16⁺ syngeneic mouse tumor growth, without impacting spontaneous HPV-specific CD8⁺ T cell responses^[1].