Cellular thermal shift assay (CETSA): CETSA assay was performed as described previously, with minor modifications. K562 cells were incubated with the indicated inhibitors (or DMSO) for 24h. Cells were harvested by centrifugation (400 x g for 5 min at RT) and washed three times with PBS. The pellets were dissolved in PBS and later equally divided into 200 µL-PCR tubes. Solutions were heated at the indicated temperature gradient for 3 min (T-Gradient Cycler, Biometra). Aliquots were then snap-freeze in liquid nitrogen and thawed at 25°C in a thermal cycler (GeneAMP PCR System2700, Applied Biosystems) three times, followed by centrifugation at 10000 x g for 20 min at 4°C. The supernatants were harvested and protein levels were measured by quantitative simple western immunoassay (JESS, BioTechne, MN, USA). Protein levels represented by the area under the curve of the electropherograms were normalized to the lowest temperature set as 0% degradation. ΔT m for compounds were determined by plotting normalized data using sigmoid dose curve and nonlinear regression (GraphPad Prism 8.0.2).