FIGURE 7.

NOX1 knock-down in PTP1B^−/− hepatocytes recovers the apoptotic response to TGF-β and Smad2 phosphorylation, inhibiting p65 nuclear translocation. PTP1B^−/− cells were transfected with either an unspecific siRNA (Uns.) or NOX1 siRNA (NOX1) and then treated or not with TGF-β. A, real-time PCR of NOX1 at 12 h. B, cell death measured as percentage of apoptotic nuclei at 30 h (left) or caspase-3 activity at 16 h (right). C, percentage of p65-positive nuclei. D, percentage of phospho-Smad2-positive nuclei. E, Western blot of total lysates. β-Actin was used as loading control. Data represent the mean ± S.E. (error bars) of two experiments with duplicate or triplicate wells. Student's t test was calculated versus unspecific siRNA: *, p < 0.05; **, p < 0.01;***, p < 0.001).