FIGURE 7.

Inhibition of mTOR increases the levels of cleaved caspase-3 in STAT1- and KPNA1-dependent fashion. A, A549 cells were incubated without or with LPS/IFN-β (5 μg/ml/250 units/ml) in the absence or presence of 50 ng/ml rapamycin (Rap) or 20 μm staurosporine for 24 h before generation of whole cell lysates and detection of the indicated proteins by Western blot analysis. Band densitometry for cleaved caspase-3 is shown for each lane (lower panel). B, A549 cell were transfected with scrambled control (Scr) or anti-KPNA1 (KPNA1) siRNA 48 h before the addition of vehicle or rapamycin in the absence or presence of LPS/IFN-β for 24 h and Western blot analysis. C, untransfected 2fTGH or U3A cells were exposed to vehicle or 50 ng/ml rapamycin for 24 h before Western blot analysis. D, U3A cells were transfected with mammalian expression plasmids for wild-type (WT) STAT1 or that containing the Y701F or L407A mutations 24 h before the addition of vehicle or 50 ng/ml rapamycin for 24 h and Western blot analysis. For B and C, mean band densitometry (± S.E.) for cleaved caspase-3 is shown in the lower panels and represents three or four individual experiments. *, p < 0.05 versus control; †, p < 0.05 versus LPS/IFN-β alone; ns, not significant by Student's t test.