Figure 6. sNEDD4 upregulates Mcl-1 to overcome nutrient deficiency-induced apoptosis.
Stable cells were treated in the presence or absence of low-serum conditions (medium with 1% serum) for 48 h, followed by Annexin V-propidium iodide (PI) double staining, and the proportion of apoptotic cells determined via flow cytometry (A) Protein expression patterns of these cells were determined using Western blot (B) (C) P1 and sN1 cells were transiently transfected with control (shLacZ) or Mcl-1 shRNA (shMcl-1) for 48 h, cultured in low-serum conditions for a further 48 h, and Casp3 activation analyzed. (D) qRT-PCR was used to determine Mcl-1 mRNA levels of stable cells. (E) Mcl-1 protein stability was analyzed with the protein degradation assay. (F) Protein levels of sNEDD4, Mcl-1, and active Casp3 of xenograft tumors on the flanks of mice were determined. CHX, cycloheximide; *P < 0.05; **P < 0.01.