RA414

RA414 is a small molecule covalent inhibitor of RPN13, a ubiquitin receptor on the 19S regulatory particle of the proteasome. It forms a covalent adduct with Cys88 of RPN13, disrupting its association with RPN2 and impairing proteasomal degradation and deubiquitinase (UCH37) activity. The resulting inhibition leads to a buildup of polyubiquitinated protein aggregates, induction of endoplasmic reticulum (ER) stress, oxidative stress, ATP depletion, and activation of apoptotic cell death. RA414 exhibits potent anti-tumor activity in preclinical models of ovarian cancer, both in syngeneic and xenograft mouse models, and demonstrates synergy with cisplatin. Its capacity to promote proteasome substrate accumulation, modulate DNA-damage response (via impaired ubiquitin-mediated repair), and induce cell death highlights its value as an investigational antineoplastic agent[1][3].