Table S3 from HDAC6 Inhibition Releases HR23B to Activate Proteasomes, Expand the Tumor Immunopeptidome and Amplify T-cell Antimyeloma Activity

Table S3. Target specificity of HDA6 inhibitors. Compounds were tested in 10-dose IC50 mode, in triplicate, with 3-fold serial dilution starting at 1 uM. The HDAC reference compound Trichostatin A (TSA) was tested in a 10-dose IC50 with 3-fold serial dilution starting at 10 uM. HDAC6 reference compound TMP269 was tested in a 10-dose IC50 with 3-fold serial dilution starting at 10 uM. HDAC10 reference compound Quinostat was tested in a 10-dose IC50 with 3-fold serial dilution starting at 10 uM. SIRT reference compound Nicotinamide was tested in a 10-dose IC50 with 3-fold serial dilution starting at 10 uM. SIRT reference compound Suramin was tested in a 10-dose IC50 with 3-fold serial dilution starting at 100 uM. Substrates used for HDAC 1, 2, 3, and 6 were fluorogenic peptide p53 (residues 379-382) RHKK(Ac)-AMC; HDAC 4, 5, 7, 9, 11 were fluorogenic HDAC classic 2a substrate trifluoroacetyl lysine; HDAC8 was fluorogenic peptide p53 residues 379-382 and NAD; HDAC10 was Ac- spermidine-AMC; SIRTs 1, 2, and 3- fluorogenic peptide p53 residues 379-382 and NAD; SIRT5- fluorogenic peptide Ac-Lys-succ and NAD. Curve fits were performed where enzyme activities at the highest compound concentration were <65%. No inhibition indicates that compound activity was negligible and could not be fit to an IC50 curve. IC50 value higher than 1.00E-06 M was estimated based on the best curve fitting available. Assays were determined in collaboration with Reaction Biology (Malvern, PA).