Figure 4. PLX8394 prevents significant paradoxical ERK1/2 activation in WT BRAF melanomas.
A. Western blot analysis of WT/WT melanoma cell lines after treatment with DMSO, vemurafenib (1 μM), PLX8394 (0.5 μM) or trametinib (50 nM) for 48 hours. B. Quantitation of the normalized pERK1/2 signal from A. C. As in Fig 2B, except that two different WT/WT melanoma cells were used to form xenografts and were processed/treated in the ex vivo explant system. Western blot analysis of lysates prepared from explants treated with DMSO, vemurafenib or PLX8394 after 48 hours. Densitometry results of pERK1/2 to ERK2 are indicated. D. WT/WT patient sample explants (TJU-MEL-29) were treated as in A for 48 hours. Densitometry values are shown.