CHEMBL5735446

ELISA (H3K27 Methylation) Assay: Representative compounds of the present invention were serially and separately diluted 3-fold in DMSO to obtain a total of eight or twelve concentrations. Then the compounds were added to G401 cell cultured in 384-well plate at 1:500 dilution to obtain the highest concentration of 20 μM. The cells were further cultured for 48 h before ELISA procedure.Histone extraction: Cells, in 384-well plate, were washed with PBS (10×PBS buffer (80 g NaCl (Sigma, S3014), 2 g KCl (Sigma, 60128), 14.4 g Na2HPO4 (Sigma, S5136), 2.4 g KH2PO4 (Sigma, P9791) to 1 L water, pH to 7.4) and lysed with the addition of lysis buffer (0.4N HCl; 45 μL per well). The plate was gently agitated at 4° C. for 30 min. The cell lysate was neutralized with neutralization buffer (0.5 M sodium phosphate dibasic, pH 12.5, 1 mM DTT; 36 μL per well). The plate was agitated to ensure the lysates were well mixed prior to the ELISA protocol.ELISA protocol: Cell lysates were transferred to the wells of a 384-well plate and the final volume was adjusted to 50 μL per well with PBS. The plate was sealed, centrifuged at 2,000 rpm for 2 min and incubated at 4° C. for about 16 h. The plate was washed with TBST buffer (1×TBS (10×TBS: 24.2 g Tris (Sigma, T6066), 80 g NaCl (Sigma, S3014) to 1 L of water and adjust pH to 7.6 with HCl) with 0.1% Tween-20). Blocking buffer (TBST, 5% BSA; 50 μL per well) was added and the plate was incubated for 1 h at rt. The blocking buffer was removed and primary antibody was added (30 μL per well). The following dilutions were performed with blocking buffer: for anti-H3K27me3 antibody (Cell Signaling Technology, #9733), dilution was 1:1000; for anti-H3K27me2 antibody (Cell Signaling Technology, #9288), dilution was 1:100; for anti-H3 antibody (Abcam, Cat #24834), dilution was 1:1000. The primary antibody was incubated in the plate at rt for 1 h. The wells were washed with TBST and incubated with secondary antibody for 1 h at rt. For secondary antibodies, the following dilutions were carried out with blocking buffer: anti-rabbit antibody (Jackson ImmunoResearch, #111-035-003), dilution was 1:2000; and anti-mouse antibody (Cell signaling technology, #7076), dilution was 1:1000. After 1 h of incubation at rt, the wells were washed with TBST. ECL substrate (Pierce, #34080) was added at 30 μL per well and the plates were centrifuged at 2,000 rpm for 2 min. The signal was read using a PerkinElmer Envision Reader. The H3K27 methylation readouts were normalized using H3 signal and then percentage inhibition was calculated against the samples treated with DMSO. The data were then fit to a dose response curve using the program Helios to get the IC50 values of the test compound.