Fig 2: Increased TRIM21 expression is associated with PTMA expression in human bladder cancer. A-H, Two serial sections of tissue microarrays containing 60 bladder tumors and 22 non-cancerous tissues were immunostained with TRIM21 (A-D) and PTMA (E-H). Normal adjacent mucosa (A and E, scale bar = 100 µm, ×320), positive TRIM21 expression (B, scale bar = 100 µm, ×320; C, scale bar = 100 µm, ×200), nuclear PTMA expression (F, scale bar = 100 µm, ×320), cytoplasmic PTMA expression (G, scale bar = 100 µm, ×200) and negative TRIM21 or PTMA expression (D and H, scale bar = 100 µm, ×200). I, Distribution of TRIM21 expression according to the PTMA expression pattern. J, The correlation between TRIM21 and PTMA expression in terms of integrated optical density (IOD) in human bladder cancer. PTMA, prothymosin-a; TRIM21, tripartite motif-containing protein 21

Fig 3: PTMA binds and orchestrates with TRIM21 to regulate Nrf2 expression through p62/Keap1 signaling. A, Immunoprecipitation study for the interaction between endogenous TRIM21 and PTMA. Total protein lysate from BFTC905 cells was immunoprecipitated either with PTMA or IgG (as a control), then immunoblotted with TRIM21. B, Western blotting for TRIM21, PTMA, and Nrf2 in several bladder cancer cells. Numeric in red indicates the ratio of protein of interest-to-ß-actin. C-F, Western blotting for TRIM21 and Nrf2 expression while knocking down or overexpression of the PTMA gene in the indicated cells. G, Western blotting for heme oxygenase-1 (HMOX1) and superoxide dismutase-2 (SOD2) expression in J82 cells with ectopic expression of WTPTMA and ? NLSPTMA. IgG, immunoglobulin G; Keap1, Kelch-like ECH-associated protein 1; Nrf2, nuclear factor erythroid 2-related factor 2; PTMA, prothymosin-a; TRIM21, tripartite motif-containing protein 21