Figure 1. CDK4/6 and MEK inhibition in RAS^mut models elicits potent cell cycle inhibition.

A. Heat map representing the relative growth rate of HT1080 cells in response to MEK inhibitors from a drug library at a concentration of 100 nM. B. Live-cell imaging tracking HT1080 cell growth when treated with DMSO, CDK4/6i (Palbociclib, 100 nM), MEKi (Trametinib, 25 nM), or CDK4/6i and MEKi in combination at indicated concentrations for 96 h. C. BrdU incorporation was assessed in HT1080 cells treated with CDK4/6i (Palbociclib, 100 nM) or MEKi (Trametinib, 25 nM) alone, or in combination at indicated concentrations for 72 h. D. Heatmap illustrating relative BrdU incorporation after 72 h of treatment. Synergy was determined using the BLISS method. E. Live-cell imaging tracking MIA PaCa-2 cell growth when treated with DMSO, CDK4/6i (Palbociclib, 100 nM), MEKi (Trametinib, 12.5 nM), or CDK4/6i and MEKi in combination at indicated concentrations for 96 h. F. BrdU incorporation in MIA PaCa-2 cells treated with DMSO, CDK4/6i (Palbociclib, 100 nM), MEKi (Trametinib, 12.5 nM), or CDK4/6i and MEKi in combination for 72 h. G. Heatmap illustrating relative BrdU incorporation after 72 h of treatment. Synergy was determined using the BLISS method. H. qPCR analysis of E2F target genes (CCNA2 and EZH2) in HT1080 cells treated with DMSO, CDK4/6i (Palbociclib, 100 nM), MEKi (Trametinib, 25 nM), or CDK4/6i and MEKi in combination for 48 h. I. Immunoblot analysis of cell cycle proteins in HT1080 cells treated with DMSO, CDK4/6i (Palbociclib, 100 nM), MEKi (Trametinib, 25 nM), or CDK4/6i and MEKi in combination for 48 h. J. Representative propidium iodide-flow cytometry analysis of HT1080 cells treated with DMSO, CDK4/6i (Palbociclib, 100 nM), MEKi (Trametinib, 25 nM), or CDK4/6i and MEKi in combination for 48 h. Error bars represent standard deviation (SD) from triplicates. *p < 0.05, **p < 0.01, ***p < 0.001, as determined by one-way ANOVA with multiple comparisons.