Figure 5.

DSF/Cu increases K48-ubiquitinated protein accumulation and induces NPL4 aggregation. HGC-27 and SGC-7901 were exposed to Cu (0.2 μM), DSF (0.24 μM, 0.3 μM), and DSF + Cu (0.24 μM, 0.3 μM + 0.2 μM) for 24 h. (a–d) Expression levels of K48-ubiquitinated protein with NPL4.β-actin as the loading control. (e–h) DSF/Cu induces rapid cytoplasmic accumulation of K48-ubiquitinated proteins. NPL4 aggregation was visualized using immunofluorescence staining after pre-extraction. Scale bar: 10 µm. Data are expressed as mean ± standard of three independent experiments. *p < 0.05 vs. the DSF/Cu group.