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

Toxicity: Standard Handling (A)

Use only fresh DMSO for reconstitution.

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

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