Fig. 5

Repression of the PKCε-EGFR-DNA-PK axis as main determinant of miR-205-mediated radiosensitization. (a) (Left panel) qRT-PCR showing PKCε mRNA amount in DU145 or PC-3 cells transfected with miR-205, in the presence or absence of miR-Mask, compared to control cells, normalized to GAPDH. Data are reported as relative quantity (RQ) ± SD with respect to Neg cells. (Right panel) Western blot analysis showing PKCε protein amount in DU145 and PC-3 cells upon miR-205-reconstitution in the presence or absence of miR-Mask. β-Actin was used as equal protein loading controls. Cropped images of selected proteins are shown. (b) Clonogenic cell survival of DU145 (upper panel) or PC-3 (lower panel) cells transfected with miR-205, miR-Mask or both. The surviving fractions are reported as mean ± SD values from 3 independent experiments. (c) Forty-eight h after transfection with Neg or siPKCε, DU145 cells were exposed to 4 Gy and 30 and 60 min later harvested for total protein collection or subcellular protein fractionation and western blot analysis. Results showing the total amount of PKCε and phospho-EGFR (upper panel) and of nuclear phospho-DNA-PK levels (lower panel) are reported. Vinculin and HDAC were used as control for total and nuclear fractions, respectively. Cropped images of selected proteins are shown. The level of significance was represented as *p < 0.05, **p < 0.01, ***p < 0.001, Student’s t-test