Fig. 5. Inhibition of Mdm2 and mTOR prevents Met-triggered cell survival in vitro. (A) Death of primary hepatocytes was triggered by actinomycin D (ActD) plus TNF. Hgf-mediated cell survival was prevented by blocking Mdm2 function using the Mdm2 inhibitor Nutlin-3 or Mdm2 siRNA. The Hgf survival effects were also impaired by the mTOR inhibitor rapamycin (1 µM). (B) Quantitative analysis of cell death in primary embryonic hepatocyte cultures treated or not with actinomycin D plus TNF (AT), Hgf (H), actinomycin D plus TNF plus Hgf (ATH), Nutlin3, Mdm2 RNA interference and rapamycin. Data are representative of three independent experiments performed in duplicate. ^**P<0.001; Student's t-tests. (C) Western blot analysis showing that Mdm2 siRNA causes a reduction in Mdm2 protein levels in a concentration-dependent manner (50, 100 and 170 pmol). A non-silencing siRNA was used as control at concentration of 100 and 170 pmol. Control siRNA did not affect Mdm2 protein levels.