Fig. 3

JQ1 increases FBP1 protein level through disrupting the interaction between FBP1 and TRIM28. a, reciprocal co-immunoprecipitation of endogenous FBP1 and TRIM28 proteins in PANC-1 cells. b, western blot analysis of FBP1 proteins in PANC-1 whole-cell lysate pulled down by GST or GST-TRIM28 recombinant proteins. Schematic diagram depicting a set of GST-TRIM28 recombinant protein constructs. c and d, PANC-1 cells were transfected with indicated plasmids. After 24 h transfection, cells were treated with or without 2 μM of JQ1 for another 24 h. Western blot analysis of whole cell lysate and co-IP samples from PANC-1 cells. e-h, PANC-1 and SW1990 cells were infected with control or TRIM28-specific shRNAs. After 24 h, cells were treated with or without 2 μM of JQ1 for another 24 h. Cells were harvested for western blot analysis (e) and RT-qPCR (f) after 48 h transfection. The spent medium was collected for measurement of glucose consumption (g) and L-lactate production (h). Data are shown as means ± SD (n = 3). *, P < 0.05; n.s., not significant. i, PANC-1 cells were infected with control or TRIM28-specific shRNAs. After 24 h, cells were treated with or without 2 μM of JQ1 for another 24 h. Cells were harvested for western blot analysis. Cells were treated with or without 20 μM of MG132 for 8 h before harvested. j, Schematic diagram shows that JQ1 binds to the BOMO domain of TRIM28 and disrupts the interaction of FBP1 with TRIM28 to protect the FBP1 from degradation by TRIM28 in PDAC