Relation between ABL1 mRNA or BCR::ABL1 p190 transcript expression and ex vivo imatinib sensitivity. (A) Correlation between ABL1 mRNA expression and the AUC as determined in an ex vivo imatinib sensitivity assay plotted per (PDX–expanded) primary ALL sample. (B) Correlation between BCR::ABL1 p190 transcript expression and the AUC plotted per (PDX–expanded) primary ALL sample. Correlation was calculated using Spearman correlation; AUC values that exceeded the maximum value of 150 AU for imatinib were artificially adjusted to the 150 AU to classify it as nonresponsive.