Fig. 6
HSP70 inhibition increases the nuclear accumulation of mutant Blimp-1 proteins to suppress the proliferation of lymphoma cells. A co-IP assay was performed to evaluate the association of endogenous Blimp-1 mutants with PML, Hrd1 and HSP70 in SUDHL-2 (a) and RJ-Lym1 (b) lymphoma cells as indicated. SUDHL-2 or RJ-Lym1 cells were transfected with si-Hrd1 (c) or si-HSP70 (d) in parallel with those treated with MG132. Blimp-1 levels were measured by western blotting. e SUDHL-2 cells or RJ-Lym1 cells were treated with MG132 (1 μM) or VER155008 (30 μM) for 24 h, and Blimp-1 levels were measured by western blotting. f SUDHL-2 cells or RJ-Lym1 cells were treated with MG132 (1 μM) or VER155008 (30 μM) for 24 h, stained with a Blimp-1 antibody (red) and DAPI (blue), and then observed under a confocal microscope. Scale bar: 5 μm. g The plasma cell differentiation of SUDHL-2 cells or RJ-Lym1 cells was assessed by flow cytometry after treatment with MG132 or VER155008 for 48 or 24 h. The location in the cell cycle (h) or survival (i) of SUDHL-2 cells and RJ-Lym1 cells was assessed by flow cytometry after treatment with MG132 or VER155008 for 48 or 24 h. j SUDHL-2 cells stably transfected with control shRNA or with Blimp-1 shRNA were further treated with VER155008 for 48 h. The cell differentiation, survival, and location in the cell cycle were assessed by flow cytometry. Data are represented as mean ± SD. ***P < 0.01, *P < 0.05
