Figure 6. Cell signaling analysis in BRAF mutant tumors treated with dabrafenib, trametinib, and palbociclib identify pRb-Ser780 as biomarker.

(A) Ten mice were dosed, as previously described, with the indicated treatments and protein lysates were extracted from snap frozen tumors collected at the end of the study. Immunoblotting using the antibodies indicated were repeated in triplicates using all mice, representative blots are shown (N = 3). (B) pRb-Ser780 relative intensities were normalized to beta actin rather than total pRb due to variability within total pRb protein levels ± standard deviation. Statistical analysis is compared between no treatment and treated samples using a 2-sample t-test. The data used for this analysis were the raw mean values. (C) Representative images and (D) statistical analyses for DTP salvage therapy.