Figure 1.

Ranpirnase inhibits NF-κB nuclear translocation induced by TNF-α in mesothelioma (MM) cells. (A) Western blotting of nuclear extracts from PPM-Mill and REN cells, probed with NF-κB p65 and histone 1 antibodies. Cells were preincubated 72 hours with the indicated concentrations of ranpirnase (Onconase [ONC]) or with vehicle (-), followed by a treatment with 1 ng/mL TNF-α for 30 minutes (+). TNF-α induced NF-κB nuclear translocation in both cell types, but in cells pretreated with 20 µg/mL ranpirnase, nuclear translocation was significantly inhibited. The ratio between NF-κB p65 and histone 1 band intensities, measured by a densitometer, is shown in the lower bar graphs, generated by Image-J software. Asterisks (*) indicate P < 0.05 significance. (B) Immunofluorescence analysis with rabbit polyclonal NF-κB antibodies on PPM-Mill and REN cells. In cells treated with 1 ng/mL TNF-α, the nuclear localization of NF-κB was evident, while this was inhibited when cells were preincubated with 20 µg/mL ranpirnase (ONC). Secondary anti-rabbit antibodies were conjugated with Alexa Fluor 568 fluorochrome (red).