Animal experiment:

Mice: Mice are treated with either vehicle (0.5% hydroxymethylcellulose, 0.1% Tween80) or AZD5153 by oral gavage mini-pump infusion. For continuous administration of AZD5153, compound is solubilized in 20% v/v DMSO/60% v/v HP-B-CD in water, loaded into a mini pump and implanted subcutaneously in mice. Tumor fragments collected are snap frozen or fixed in 10% buffered formalin. Blood samples are collected from the same mice and stabilized in EDTA. Plasma concentrations are determined by liquid chromatography/tandem mass spectrometry method[1].

AZD5153 6-Hydroxy-2-naphthoic acid is the 6-Hydroxy-2-naphthoic acid of AZD5153. AZD5153 is a potent, selective, and orally available BET/BRD4 bromodomain inhibitor; disrupts BRD4 with an IC50 of 1.7 nM. IC50: 1.7 nM (BRD4)[1]

AZD5153 demonstrates a remarkable enhancement in potency for the displacement of full-length BRD4 relative to BD1, with IC50 values of 5.0 nM and 1.6 μM, respectively. AZD5153 potently disrupts BRD4 foci in U2OS cells with an IC50 value of 1.7 nM. AZD5153 efficiently down-regulates MYC protein levels across the cell line panel irrespective of their sensitivity to AZD5153[1].

Administration of AZD5153 leads to tumor stasis or regression in multiple xenograft models of acute myeloid leukemia, multiple myeloma, and diffuse large B-cell lymphoma. AZD5153 treatment markedly impacts transcriptional programs of MYC, E2F, and mTOR[1].

[1]. Rhyasen GW, et al. AZD5153: A Novel Bivalent BET Bromodomain Inhibitor Highly Active against Hematologic Malignancies. Mol Cancer Ther. 2016 Nov;15(11):2563-2574.