Fig. 2

Anti-EGFR SR PDX models can be generated with high efficiency. a Representative example of primary responses observed within the initial 21 days of treatment with anti-EGFR mAb (CET) in colon cancer PDX models. PDX model BoC56 with primary resistance due to KRAS G12C mutation, PDX BoC139 with primary resistance despite KRAS, NRAS, BRAS, and PIK3A wild type status, PDX BoC106 with stable disease, and PDX BoC18 with partial response and quadruple wild type status. b Representative growth pattern of PDX models with long-term CET treatment and initial treatment response to anti-EGFR therapy. Time to progression was defined by the mean growth curve crossing the PD borderline. Arrows indicate the time point progressive disease was observed. PD, progressive disease; PR, partial response; gray shades area, stable disease. Relative growth curves are derived from mean values ± SEM (error bars). *, each star represents a tumor that was taken out of the treatment cohort at the indicated time point. Please note that this can lead to marked changes in mean tumor volumes (see also Additional file 4: Table S3 for individual growth curves). c Summary of PDX models tested