Journal: Cell Reports Medicine

Article Title: Augment proteasome inhibitor efficacy activates CD8 + T cell-mediated antitumor immunity in breast cancer

doi: 10.1016/j.xcrm.2025.102211

Figure Lengend Snippet: TM and AMD3100 treatment reduced PSMB5 levels by inhibiting STAT3 signaling (A) Schematic of the proteasome activity reporter utilized. (B–D) Treatment with TM or AMD3100 decreased (B) proteasome activity and (C and D) PSMB5 protein levels in cancer cells. (E) Inducible knockdown of PSMB5 sensitized human breast cancer cell line MDA-MB-231 to BTZ treatment; n = 3. (F) High PSMB5 protein level was observed in cancer cells with low sensitivity to BTZ analyzed via DepMap database. (G) Prediction of transcription factors (TFs) that can regulate PSMB5 expression using 5 different algorithms. The overlapped 20 TFs were summarized. (H) Positive expression correlation of STAT3 and PSMB5 in cancer cells was analyzed at DepMap database. (I) Treatment with TM or AMD3100 gradually decreased the phosphorylation level of STAT3 in cancer cells. (J) Knockdown of STAT3 decreased phosphorylated STAT3 and PSMB5 protein levels. (K and L) (K) Inducible knockout or (L) pharmaceutical inhibition of STAT3 sensitized cancer cells to BTZ treatment; n = 3. (M) Inhibition of STAT3 by Stattic decreased proteasome activity in cancer cells; n = 3. (N and O) Activation of STAT3 by EGF increased (N) PSMB5 protein levels and (O) proteasome activity in cancer cells; n = 5. (P) EGF treatment rescued the decrease of PSMB5 protein levels induced by TM or AMD3100. (Q) Low STAT3 levels are associated with better survival in multiple myeloma patients treated with BTZ. (R) Working model showing that TM or AMD3100 treatment reduced PSMB5 protein levels through inhibiting STAT3 phosphorylation. See also . Data are presented as the means ± SDs. Statistical significance was analyzed by Student’s t test or one-way ANOVA with Bonferroni test. ∗ p < 0.05; ∗∗∗ p < 0.001; ∗∗∗∗ p < 0.0001.

Article Snippet: PSMB5 , Cell Signaling Technology , Cat#: 12919; RRID: AB_2798061.

Techniques: Activity Assay, Knockdown, Expressing, Phospho-proteomics, Knock-Out, Inhibition, Activation Assay

Journal: Cell Reports Medicine

Article Title: Augment proteasome inhibitor efficacy activates CD8 + T cell-mediated antitumor immunity in breast cancer

doi: 10.1016/j.xcrm.2025.102211

Figure Lengend Snippet: AMPKα serves as an upstream inhibitory signal for STAT3 (A) Top downregulated pathways induced by TM or AMD3100 treatment as analyzed by GSEA. (B and C) TM or AMD3100 treatment (B) decreased intracellular ATP levels ( n = 6) and (C) induced AMPKα phosphorylation to activate AMPKα signaling. (D) High level of phosphorylated AMPKα at Thr172 indicated high sensitivity to BTZ in cancer cells analyzed via DepMap database. (E and F) (E) AMPKα activation by metformin decreased, while (F) its inhibition by Comp C increased proteasome activity in cancer cells; n = 3. (G and H) Manipulating the activation status of AMPKα affected the sensitivity of cancer cells to BTZ treatment; n = 3. (I) Inhibition of AMPKα by Comp C rescued the decrease in PSMB5 protein levels induced by TM or AMD3100. (J) Activation of AMPKα by metformin decreased STAT3 phosphorylation and PSMB5 protein levels. (K and L) (K) A high PRKAA1/2 level and (L) a low STAT3/PRKAA1 or STAT3/PRKAA2 ratio are associated with improved post-progression survival in multiple myeloma patients treated with BTZ. (M) Working model showing that TM or AMD3100 treatment reduced PSMB5 protein levels by affecting the AMPKα/STAT3 axis. See also . Data are presented as the means ± SDs. Statistical significance was analyzed by Student’s t test or one-way ANOVA with Bonferroni test. ∗ p < 0.05; ∗∗∗ p < 0.001; ∗∗∗∗ p < 0.0001.

Article Snippet: PSMB5 , Cell Signaling Technology , Cat#: 12919; RRID: AB_2798061.

Techniques: Phospho-proteomics, Activation Assay, Inhibition, Activity Assay

Journal: Viruses

Article Title: HBV Infection Drives PSMB5-Dependent Proteasomal Activation in Humanized Mice and HBV-Associated HCC

doi: 10.3390/v17111454

Figure Lengend Snippet: HBV infection enhances PSMB5 expression in liver-humanized mice. ( A ) 10-year survival analysis of low (bottom 75% of TPM) and high (top 25% of TPM) PSMA1 expressing HCC patients using GEPIA: a web server for cancer and normal gene expression profiling and interactive analyses . HBV infection increases PSMB5 gene expression levels of liver humanized mice livers. ( B ) Schematic overview of HBV infection in uPA-NOG liver-humanized mice. ( C ) Human albumin levels in mouse serum, 8 weeks post-transplantation ( D ) H&E staining of mouse liver tissue. ( E ) Anti-human mitochondria staining indicating engrafted human hepatocytes after 12 weeks of infection. ( F ) Relative mRNA expression of 26S proteasome subunits in livers of HBV-infected vs. non-infected mice ( n = 4/group). TPM: Transcripts per million. Scale bar: 100 μm.

Article Snippet: The plasmid targeting the human PSMB5 gene (#117073) and the LentiCRISPRv2 plasmid with blasticidin selection (#83480) were obtained from Addgene (Watertown, MA, USA).

Techniques: Infection, Expressing, Gene Expression, Transplantation Assay, Staining

Journal: Viruses

Article Title: HBV Infection Drives PSMB5-Dependent Proteasomal Activation in Humanized Mice and HBV-Associated HCC

doi: 10.3390/v17111454

Figure Lengend Snippet: Functional consequences of PSMB5 knockout in human THP-1 cells. ( A ) Ten-year survival analysis of low (bottom 75% of TPM) and high (top 25% of TPM) PSMB5 expressing HCC patients using GEPIA: a web server for cancer and normal gene expression profiling and interactive analyses . ( B ) PSMB5KO cells accumulate ubiquitinated proteins due to decreased protein degradation. Western blot analysis showing accumulation of ubiquitinated proteins in PSMB5-deficient (KO) THP-1 cells compared with wild-type (WT) controls on day 7. ( C ) Flow cytometric analysis of MHC I surface expression in WT and PSMB5KO THP-1cells at days 7 and day 14 post-transduction. ( D ) Relative mRNA expression levels of antigen-processing pathway genes in WT ( n = 3) and PSMB5-KO ( n = 3) THP-1 cells. WT: wild-type control; KO: PSMB5 knockout. * p < 0.05.

Article Snippet: The plasmid targeting the human PSMB5 gene (#117073) and the LentiCRISPRv2 plasmid with blasticidin selection (#83480) were obtained from Addgene (Watertown, MA, USA).

Techniques: Functional Assay, Knock-Out, Expressing, Gene Expression, Western Blot, Transduction, Control

Journal: Viruses

Article Title: HBV Infection Drives PSMB5-Dependent Proteasomal Activation in Humanized Mice and HBV-Associated HCC

doi: 10.3390/v17111454

Figure Lengend Snippet: Elevated β5 subunit expression and proteasome activity in HBV-infected human tissues. ( A ) Differential expression of PSMB5 gene in tumor and corresponding normal tissue from patients with HCC using GEPIA . HBV infected patients have higher levels of β5 protein expression and proteasome activity levels. Liver and serum samples of HBV, HCC and HBV-induced HCC patients were collected; ( B ) proteasome subunit β5 protein expression and ( C ) proteasome activity were analyzed with ELISA methods. * p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001.

Article Snippet: The plasmid targeting the human PSMB5 gene (#117073) and the LentiCRISPRv2 plasmid with blasticidin selection (#83480) were obtained from Addgene (Watertown, MA, USA).

Techniques: Expressing, Activity Assay, Infection, Quantitative Proteomics, Enzyme-linked Immunosorbent Assay

Journal: iScience

Article Title: Ubiquitination and degradation of CD47 enhances macrophage phagocytosis of hemolytic erythrocytes

doi: 10.1016/j.isci.2025.114499

Figure Lengend Snippet: Changes in the major protein components of the proteasome during hemolysis (A) Western blot analysis of proteasomal subunits (PSME1/2, PSMB5/6/7) expression in control and hemolysis groups. (B and C) Quantification of proteasomal subunits (PSME1/2, PSMB5/6/7) expression in the RBC membrane (B) and cytoplasm (C) ( n = 3). (D) Representative immunofluorescence images of proteasomal subunits (PSME1/2, PSMB5/6/7) of hemolytic RBCs ( n = 6). Scale bars = 10 μm. (E) Schematic illustration of the animal model of immune hemolysis. (F and G) Immunofluorescence of proteasomal subunits (PSME1/2, PSMB5/6/7) in hemolytic mouse RBCs (F) and AIHA patient RBCs (G) ( n = 6). Scale bars = 10 μm. (H–J) Statistical analysis of caspase-like activity (H), trypsin-like activity (I), and chymotrypsin-like activity (J) of the membrane proteins after hemolysis ( n = 6). Data were analyzed by Student’s t test (two groups) or one-way ANOVA with Tukey’s test (multiple groups) and are expressed as mean ± SEM. ∗ p < 0.05, ∗∗∗ p < 0.001, ns = no significance.

Article Snippet: The primary antibodies utilized in this procedure were CD47 (Santa Cruz Biotechnology, Cat# sc-12730), MARCH1 (HUABIO Biotechnology, Cat# ER63906), PSME1 (Abcam, Cat# ab186832), PSME2 (Abcam, Cat# ab183727), PSMB5 (BOSTER, Cat# A03418-1), PSMB6 (ABclonal Technology, Cat# A4053), PSMB7 (BOSTER, Cat# A08095-1), and UBQLN1 (Proteintech Group, Cat# 22126-1-AP).

Techniques: Western Blot, Expressing, Control, Membrane, Immunofluorescence, Animal Model, Activity Assay