Figure 5: Relief of ERK-dependent feedback potentiates RTK signaling, which in turn activates RAC1 and cell migration.
A. MEFs expressing BRAFV600E (1ug/ml doxycycline 24h) were treated with Trametinib for 24h, and WCL was collected. WCLs were analyzed by an RTK array to profile phosphorylated RTKs. MEFs with empty vector was used as control.
B. YUMM 3.3 were treated with 10nm Trametinib for indicated times, and WCL was IB for indicated proteins.
C. YUMM 3.3 were pretreated with 1uM PDGF receptor inhibitor CP673451(CP) for 1 hour followed by DSMO or 10nM Trametinib (24h). WCL was collected and subjected to RAC1 PD assay or IB for indicated proteins.
D. Migration of YUMM 3.3 cells treated with DMSO, 10 nM Trametinib, and 1uM CP alone or in combination with Trametinib. Cell Index at 24 hours is normalized to DMSO control and plotted as a bar graph for all three PDGFR inhibitors used.
Vertical error bars on curve represents mean ± SEM (n=3).
Also, see SF5