Supplementary Figure 4.

Inhibition of IKBKE leads to feedback activation of the RTKs/MAPK pathway. A, Amlexanox treatment at a concentration of 50 and 100 μM to L3.6pl cells for 24 h increased pERK1/2 expression and decreased pSTAT3 and pAKT expression compared to vehicle. B, IKBKE inhibitor (CYT387) treatment at a concentration of 1 and 4 μM for 24 h led to increased pERK1/2 expression in multiple PDAC cell lines compared to vehicle. C, L3.6pl cells treated with CYT387 (2 μM) showed prolonged activation of the BRaf-MEK-ERK pathway at a time-dependent manner. D, L3.6pl cells transfected with IKBKE siRNAs also demonstrated the increased pERK1/2 expression compared to control siRNA.