Figure 3

Crosstalk among DTX3L, ARTD8 and ARTD9 mediates chemo-resistance and survival in PC3 cells and is dependent on ADP-ribosylation. (A) Cell viability analyses of PC3-siMock, PC3-siDTX3L, PC3-siARTD8 and PC3-siARTD9 single knockdown cells were assessed by the trypan blue exclusion assay. Cells were treated as indicated with IFNγ and/or docetaxel (DT) and counted after 48 h, NT: not treated, CT: control treatment (solvent). Values represent the means of three independent experiments, and the error bars represent the SE. Statistical analysis was performed using the Student's t test. *P < 0.05, **P < 0.001 and ***P < 0.0001 (B) Cell viability analyses of PC3-siMock, PC3-siDTX3L/siARTD8, PC3-siDTX3L/siARTD9 or PC3-si ARTD9/siARTD8 double knockdown cells were assessed by the trypan blue exclusion assay. Cells were treated as indicated with IFNγ and/or docetaxel (DT) and counted after 48 h, NT: not treated, CT: control treatment (solvent). Values represent the means of three independent experiments, and the error bars represent the SE. Statistical analysis was performed using the Student's t test. *P < 0.05, **P < 0.001 and ***P < 0.0001. (C) Cell viability analyses of PC3-siMock, PC3-siDTX3L, PC3-siARTD8 and PC3-siARTD9 single knockdown cells treated in presence or absence of docetaxel (DT) (0.5 nM) with the ARTD1/2-specific inhibitors Olaparib (1 μM) and Veliparib (1 μM) or with the more ARTD7/8-specific inhibitors DPQ (7.5 μM) and TIQ-A (7.5 μM) were assessed by the trypan blue exclusion assay. Values represent the means of three independent experiments performed in triplicate, and the error bars represent the SE. Statistical analysis was performed using the Student's t test. *P < 0.05, **P < 0.001 and ***P < 0.0001.