DOT1L Inhibitor, EPZ004777

A cell-permeable S-adenosylmethionine (AdoMet/SAM) structural derivative that potently inhibits DOT1L methyltransferase activity (IC₅₀ = 400 pM) in a SAM-competitive (K_i = 300 pM) manner via a 1:1 stoichiometric interaction (K_D = 250 pM), not only blocking DOT1L SAM-binding site with its deazaadenosine moiety, but also disrupting the overall structural integrity of the catalytic pocket with its tert-butylphenyl moiety, while inhibiting PRMT5 only at much higher concentrations (IC₅₀ = 521 nM or 25 µM, respectively, using free or MEP50-complexed PRMT5) and exhibiting little potency against CARM1, EHMT2, EZH1, EZH2, PRMT1, PRMT8, SETD7, or WHSC1 even at a high concentration of 50 µM. Although EPZ004777 effectively inhibits cellular H3K79 methylation regardless of MLL translocation status (IC_max ~3 µM post 4 d treatment in MV4-11, MOLM-13, and Jurkat cells with MLL-AF4, MLL-AF9, and no MLL rearrangement, respectively), the viability of MLL rearranged cells are more susceptible to EPZ004777 treatment (IC₅₀ = 0.62 to 6.74 µM in cultures with MLL-AF4, MLL-AF9, or MLL-ENL fusion; GI₅₀ =13.9 µM to no inhibition at 50 µM in cultures with no MLL rearrangement; by Guava ViaCount Assay/4000-0040 at the end of 14 to 18 treatment period; cells split with fresh media/inhibitor every 3-4 d) due to effective transcription blockage of MLL fusion target genes (IC₅₀ ~700 nM in reducing HOXA9 & MEIS1 mRNA levels in MV411 & MOLM-13 cultures). Despite poor pharmacokinetic properties, continuous EPZ004777 infusion via subcutaneously implanted osmotic pumps (100 mg/mL & 150 mg/mL to achieve steady state plasma drug conc of 0.64 & 0.84 µM, respectively) is reported to significantly extend the survival of NSG mice received MV4-11 cells via tail vein injection (100% death on d11 or d17 post 14 d vehicle or drug infusion period, respectively).

A cell-permeable, non-toxic, a near chemical derivative of S-adenosylmethionine (SAM) that competitively binds to the SAM-binding pocket of DOT1L and inhibits its activity in a reversible manner (IC₅₀ = 400 pM; K_i = 300 pM). Shown to inhibit the methylation of cellular H3K79 in MLL cells and block the expression of leukemogenic genes. Displays excellent selectivity over other histone methyltransferases PRMT5 (IC₅₀ = 521 nM), CARM1, EHMT2, EZH1, EZH2, PRMT1, PRMT8, SETD7 and WHSC1 (IC₅₀ >50 µM). Inhibits the proliferation of MV4-1, MOLM-13, KOPN-8 cells (IC₅₀ = 170, 720, and 620 nM, respectively) and suppresses the growth of MV4-11 xenografts in nude mice model (50 mg/ml, s.c. minipump infusion). Blocks the cell cycle at G0/G1 phase and induces apoptotic cell death by activating caspase 3/7. Also shown to accelerate reprogramming of somatic cells into induced pluripotent stem cells.

Please note that the molecular weight for this compound is batch-specific due to variable water content.

Cell permeable: yes

Primary Target
DOT1L

Reversible: yes

Packaged under inert gas

Following reconstitution, aliquot and freeze (-20°C). Stock solutions are stable for up to 3 months at -20°C.

Use only fresh DMSO for reconstitution.

Daigle, S.R., et al. 2013. Blood.122, 1017.
Yu, W., et al. 2012. Nat. Commun.3, 1288.
Daigle, S.R., et al. 2011. Cancer Cell.20, 53.

CALBIOCHEM is a registered trademark of Merck KGaA, Darmstadt, Germany

Toxicity: Standard Handling (A)