PSMD2 regulates breast cancer cell proliferation and cell cycle progression by modulating p21 and p27 proteasomal degradation

• Published in: Cancer letters Vol. 430; pp. 109 - 122
• Main Authors: Li, Yunhai, Huang, Jing, Zeng, Beilei, Yang, Dejuan, Sun, Jiazheng, Yin, Xuedong, Lu, Mengqi, Qiu, Zhu, Peng, Weiyan, Xiang, Tingxiu, Li, Hongzhong, Ren, Guosheng
• Format: Journal Article
• Language: English
• Published: Ireland Elsevier B.V 28.08.2018; Elsevier Limited
• Subjects: Apoptosis; Biotechnology; Breast cancer; Cell cycle; Cell growth; Cell proliferation; Conflicts of interest; Cyclin-dependent kinase inhibitor p21; Enzymes; G1 phase; Gene expression; Gene set enrichment analysis; Genomes; Immunoglobulins; Investigations; Lymphatic system; Metastasis; Multivariate analysis; p21; p27; Penicillin; Proteasomes; Proteins; PSMD2; Signal transduction; siRNA; Software; Therapeutic applications; Ubiquitin; Ubiquitin-proteasome system; Xenografts; United States > US; BC; RT; IHC; E2s; HR; WB; PSMD2; Cell cycle; UPS; RT-qPCR; RFS; PBS; PCs; DUBs; E3s; OS; CI; E1s; GSEA; GST; Breast cancer; siRNA; Ub; p21; TCGA; GEO; p27; DMFS; Ubiquitin-proteasome system; RP
• ISSN: 0304-3835; 1872-7980
• DOI: 10.1016/j.canlet.2018.05.018

Alterations in the ubiquitin-proteasome system (UPS) and UPS-associated proteins have been implicated in the development of many human malignancies. In this study, we investigated the expression profiles of 797 UPS-related genes using HiSeq data from The Cancer Genome Atlas and identified that PSMD2 was markedly upregulated in breast cancer. High PSMD2 expression was significantly correlated with poor prognosis. Gene set enrichment analysis revealed that transcriptome signatures involving proliferation, cell cycle, and apoptosis were critically enriched in specimens with elevated PSMD2. Consistently, PSMD2 knockdown inhibited cell proliferation and arrested cell cycle at G0/G1 phase in vitro, as well as suppressed tumor growth in vivo. Rescue assays demonstrated that the cell cycle arrest caused by silencing PSMD2 partially resulted from increased p21 and/or p27. Mechanically, PSMD2 physically interacted with p21 and p27 and mediated their ubiquitin-proteasome degradation with the cooperation of USP14. Notably, intratumor injection of therapeutic PSMD2 small interfering RNA effectively delayed xenograft tumor growth accompanied by p21 and p27 upregulation. These data provide novel insight into the role of PSMD2 in breast cancer and suggest that PSMD2 may be a potential therapeutic target. •PSMD2 is significantly upregulated in breast cancer.•High PSMD2 expression is associated with poor prognosis in breast cancer patients.•PSMD2 knockdown inhibits cell proliferation and arrests cell cycle progression at G0/G1 phase partially via p21 and/or p27.•PSMD2 physically interacts with p21 and p27 and mediates the ubiquitin-proteasome degradation of them with USP14 cooperation.•Intratumoral injection of therapeutic PSMD2-siRNA inhibits xenograft tumor growth.