Figure 3. PTPN6 expression and response of CML cells to TKI.

KCL-22 Cells were subjected to CRISPR/Cas9 mediated knockout of the PTPN6 gene. Two individual single cell clones were analyzed for PTPN6 expression using western blot (A). K562 cells with low endogenous PTPN6 expression were stably transduced with either empty vector (EV), wild type PTPN6 (WT), or the catalytically inactive PTPN6-C453S (CS) mutant. Protein expression was analyzed by western blot (E). The engineered cells were analyzed for IC₅₀ of nilotinib (B, F), imatinib (C, G), and dasatinib (D, H). Each dot represents the IC₅₀ value determined in one independent experiment with quadruplicate technical replicas, black bars show the median of n = 3 independent experiments.