THZ531

THZ531 is a covalent inhibitor of both CDK12 and CDK13 with IC50s of 158 nM and 69 nM, respectively.

Signaling Pathways >> Cell Cycle/DNA Damage >> CDK

Research Areas >> Cancer

CDK12:158 nM (IC50)

CDK13:69 nM (IC50)

The results from Kinase assays demonstrate that THZ531 potently inhibits CDK12 and CDK13 with IC50s of 158 nM and 69 nM, respectively; whereas inhibition of CDK7 and CDK9 is more than 50-fold weaker with IC50s of 8.5 and 10.5 µM, respectively. THZ531 treatment leads to a dramatic and irreversible decrease in Jurkat cell proliferation with an IC50 of 50 nM. FACS cell cycle analysis following treatment with escalating doses of THZ531 displays a dose and time-dependent increase in the number of cells exhibiting sub-G1 content. At 50 nM THZ531, no increase in the percentage of apoptotic cells is observed over DMSO control for the time course of the experiment. Higher doses of THZ531 leads to pronounced Annexin V signal with 30 to 40% annexin V-positively stained cells by 72 hrs. A dramatic reduction in elongating Pol II following THZ531 treatment is also observed[1].

Cells are treated with THZ531 or DMSO for 6 hrs. Following treatment cells are washed 2-fold with cold PBS and then lysed in the following lysis buffer: 50 mM Hepes pH 7.4, 150 mM NaCl, 1% Nonidet P40 substitute, 5 mM EDTA, 1 mM DTT, and protease/phosphatase cocktails. Following clearance, lysates are treated with bio-THZ1 or bio-TH531 for pulldown overnight at 4°C. Lysates are further incubated at room temperature for 3 hrs to increase the efficiency of covalent bond formation. Lysates are then incubated with streptavidin agarose for pulldown for an additional 2 to 3 hrs at 4°C[1].

Jurkat cells are plated in 96-well plates at 20,000 cells/well in fresh media and treated with THZ531 or DMSO at the indicated concentrations for 72 hours. HAP1 cells are seeded in 96-well plates at 12,000 cells/well in fresh media and 24 hours later are treated with THZ531 at the indicated concentrations for 72 hours. Anti-proliferative effect of THZ531 is assessed. To assess the effect of inhibitor washout on anti-proliferation of Jurkat cells, cells are treated with THZ531 or DMSO for 6 hrs. Inhibitor-containing medium is then removed and incubated with or without THZ531 for 66 hrs. Anti-proliferative effect of THZ531 is assessed. All proliferation assays are performed in biological triplicate. IC50s are determined using non-linear regression curve fit[1].

[1]. Zhang T, et al. Covalent targeting of remote cysteine residues to develop CDK12 and CDK13 inhibitors. Nat Chem Biol. 2016 Oct;12(10):876-84.

Abemaciclib(LY2835219) | Ribociclib (LEE011) | Dinaciclib (SCH727965) | THZ1 2HCl | Roscovitine (CYC202) | RO-3306 | Flavopiridol | NVP 2 | BAY-1143572 Racemate | CYC-065 | AZD5438 | BIO | Kenpaullone | SNS-032 (BMS-387032) | CDK9-IN-2