To assess cellular target engagement of KMI169, Cellular Thermal Shift Assays (CETSA)24 were performed in human castration-resistant prostate cancer cell lines PC-3M and LNCaP-abl, which revealed strong stabilization of endogenous KMT9 (ΔTm = 9.8 K and 8.3 K, respectively) compared to KMI169Ctrl (ΔTm = 1.0 K) or DMSO (Fig. 4a, b and Supplementary Fig. 5a, b). Here, HEMK2 is linked to prostate cancer.