Fig 3.

Multiple genes distinguish imatinib responsive from secondary imatinib-resistant chronic myelogenous leukemia (CML). The contribution of the 21 test genes to accurately distinguishing ABL1 KD-unmutated secondary resistant CML-CP/AP from imatinib responsive baseline CML-CP/AP samples was determined by LDA. The prediction accuracies were estimated using randomly chosen test and training sets in 500 three-fold cross-validations are shown in (A) for training sets and in (B) for test set. The median accuracy of a model for discriminating imatinib response from secondary imatinib resistance improves by inclusion of up to 11 genes. The symbols in this Figure are as in Figures 2B and 2C. (C) The frequency of particular genes identified in these increasing gene model are shown on a bar plot, with overall frequency in all models represented by color (red to white). Prostaglandin-endoperoxide synthase (PTGS1) is not identified commonly in the models as a discriminator of secondary imatinib resistance.