26S proteasome non-ATPase regulatory subunit 8 (PSMD8)

26S proteasome non-ATPase regulatory subunit 8 (PSMD8) is a component of the 19S regulatory particle, or "lid," of the 26S proteasome holoenzyme, which governs the selective ATP/ubiquitin-dependent degradation of most intracellular proteins in eukaryotic cells[1][3][4]. By controlling protein turnover, PSMD8 and the proteasome complex are integral to cellular processes including cell cycle regulation, DNA replication, antigen processing, energy metabolism, and protein quality control[2][3]. Elevated expression of PSMD8 has been observed in multiple tumors, particularly ovarian, testicular, glioma, and melanoma, and its expression correlates with poor prognosis and advanced disease stage in ovarian cancer[2]. PSMD8 is being explored as both a potential prognostic biomarker and a therapeutic target, though drugs target the proteasome complex broadly rather than PSMD8 specifically; inhibitors like bortezomib have established efficacy in malignancies such as multiple myeloma, leveraging the essential role of the proteasome in protein homeostasis[3]. Given its crucial, ubiquitous biological functions, broad inhibition of the proteasome is associated with marked safety concerns, chiefly neurotoxicity and immunosuppression[2][3].

Other names

26S proteasome regulatory subunit Rpn12S14Nin1pp31HIP6HYPFRpn12HEL-S-91nepididymis secretory sperm binding protein Li 91n

Inhibition of proteasome activity, leading to impaired protein degradation Induction of cell cycle arrest and apoptosis in rapidly proliferating cells