Cell lines

RAW264.7 cells

Preparation Method

DOT1L enzyme inhibition enhances OC fusion and resorption ability a RAW264.7 cells pretreated with DMSO or the indicated concentrations of DOT1L inhibitors (EPZ5676 and EPZ004777) and stimulated with RANKL for 60 h. OCs were fixed and stained for TRAP.

Reaction Conditions

1 and 10 μM; 5 days

Applications

Treatment with DOT1L inhibitors (EPZ5676 and EPZ004777) increased the proportion and number of large OCs, which was approximately twice that observed in the control group. Furthermore, no significant difference was observed between the effects of treatment at 1 and 10 μM of the DOT1L inhibitors.

Animal models

BALB/c-nu mice

Preparation Method

1 × 106 HCT116 cells were subcutaneously injected in the left flank of the BALB/c-nu mice. After tumor pumped, the mice were randomly divided into two groups. One group was treated with PBS with 10% DMSO, while the other group was treated with EPZ004777 (100 mg/kg/day, diluted into PBS with 10% DMSO) for 16 days. At the termination of the experiment, tumors were removed and weighed.

Dosage form

100 mg/kg/day; i.p.

Applications

The results showed that the tumor volumes and weights of all EPZ004777-treated tumors in the nude mice were significantly smaller and lighter than the control groups, respectively.

EPZ004777, as a potent epigenetic modulators, can reverse TGF-β1 induced T regulatory cells and may be used to treat diverse immune disorders^[1].

In vitro, EPZ004777 has concentration-dependent inhibition of DOT1L enzyme activity with an IC₅₀of 400 ± 100 pM. In vitro experiment it shown that in MV4-11 cells incubated with 3 μM EPZ004777, a concentration sufficient for maximal cellular DOT1L inhibition. After treatment with 1 day, there is a apparently modest reduction in H3K79me2 levels, but full depletion took 4–5 days. In vitro efficacy test it exhibited that treatment with 3 μM EPZ004777 caused a concentration-dependent decrease of both transcripts in each cell line with IC₅₀s of approximately 700 nM.^[2]In vitro, treatment with 30 μM and 50 μM EPZ004777 obviously decreased cell viability of SW480 cells in a dose-dependent manner. Also 30 μM, 50 μM, and 70 μM EPZ004777 treatment in a dose-dependent manner inhibited the cell viability of HCT116 cells.^[3]In vitro, EPZ004777 could also inhibit the proliferation and induce the differentiation of YBT-5 cells^[4].

In vivo, nude mice bearing MV4-11 xenograft tumors loaded with a 50 mg/ml solution of EPZ004777, H3K79me2 levels were markedly decreased in tumors from mice treated with EPZ004777 compared to untreated controls.^[2]In vivo experiment it demonstated that treatment with 10 and 50 mg/kg EPZ004777 via subconjunctival injection could alleviate corneal injury and opacity.^[5].

References:
[1]Premkumar K, Shankar BS. Identification of EPZ004777 and FG2216 as inhibitors of TGF-β1 induced Treg cells by screening a library of epigenetic compounds. Life Sci. 2022 Jul 15;301:120643.
[2]Daigle SR, et al. Selective killing of mixed lineage leukemia cells by a potent small-molecule DOT1L inhibitor. Cancer Cell. 2011 Jul 12;20(1):53-65.
[3]Yang L, et al. Silencing or inhibition of H3K79 methyltransferase DOT1L induces cell cycle arrest by epigenetically modulating c-Myc expression in colorectal cancer. Clin Epigenetics. 2019 Dec 30;11(1):199.
[4]Wang Z, et al. Establishment and characterization of a DOT1L inhibitor-sensitive human acute monocytic leukemia cell line YBT-5 with a novel KMT2A-MLLT3 fusion. Hematol Oncol. 2019 Dec;37(5):617-625.
[5]Wan S, et al. Dot1l Aggravates Keratitis Induced by Herpes Simplex Virus Type 1 in Mice via p38 MAPK-Mediated Oxidative Stress. Oxid Med Cell Longev. 2021 Feb 15;2021:6612689.