Fig. 2

Functional assessment of L792F/H EGFR mutations and sensitivity to osimertinib. Functional evaluation of the L792F/H mutations was performed using an in vitro assay which uses high-content microscopy to assess activation of oncogenic signaling pathways represented by the nuclear-to cytoplasmic ratio (NCR) of signaling pathway reporters. Activity was assessed for the MAP Kinase pathway (ERK2-reporter) and JAK-STAT pathway (STAT3-reporter). a Baseline functional activity of EGFR mutations compared to wild-type EGFR. Values are average NCR for each condition, *p < 0.05 (students T test) with bracket indicating that the difference in activation between WT EGFR and each of the four mutations is significant. Presented is a representative experiment of 3 repeats. b, c Sensitivity to osimertinib was measured in escalating nMol concentrations. Values are the mean percentage (%) activation of ΔNCR (MTtx − WTut)/(MTut − WTut) normalized for each condition. 100% is the over-activation due to MT construct activity and 0% represent wild-type untreated activity at baseline. Means represented calculated from 7 independent repeats (Additional file 1: Figures S2, S3). MT mutant construct. WT wild-type construct, tx drug treated, ut untreated. d Total area under the curve (AUC) calculations for the MAP kinase pathway calculated using Graph Pad Prism. Also presented is the ratio of the AUC calculation of the tested EGFR L792 mutations and C797S-positive control versus T790M-negative control