Discovery of novel aromatase inhibitors using a homogeneous time-resolved fluorescence assay.

Abstract

AIM:

Aromatase is an important target for drugs to treat hormone-dependent diseases, including breast cancer. The aim of this study was to develop a homogeneous time-resolved fluorescence (HTRF) aromatase assay suitable for high-throughput screening (HTS).

METHODS:

A 384-well aromatase HTRF assay was established, and used to screen about 7000 compounds from a compound library. Anti-proliferation activity of the hit was evaluated using alamarBlue(R) assay in a hormone-dependent breast cancer cell line T47D. Molecular docking was conducted to elucidate the binding mode of the hit using the Discovery Studio program.

RESULTS:

The Z' value and signal to background (S/B) ratio were 0.74 and 5.4, respectively. Among the 7000 compounds, 4 hits (XHN22, XHN26, XHN27 and triptoquinone A) were found to inhibit aromatase with IC50 values of 1.60±0.07, 2.76±0.24, 0.81±0.08 and 45.8±11.3 μmol /L, respectively. The hits XHN22, XHN26 and XHN27 shared the same chemical scaffold of 4-imidazolyl quinoline. Moreover, the most potent hit XHN27 at 10 and 50 μmol/L inhibited the proliferation of T47D cells by 45.3% and 35.2%, respectively. The docking study revealed that XHN27 docked within the active site of aromatase and might form a hydrogen bond and had a π-cation interaction with amino acid residues of the protein.

CONCLUSION:

XHN27, an imidazolyl quinoline derivative of flavonoid, is a potent aromatase inhibitor with anti-proliferation activity against breast cancer in vitro. The established assay can be used in HTS for discovering novel aromatase inhibitor.

• Authors: Jin-zi Ji, Ke-jing Lao, Jie Hu, Tao Pang, Zhen-zhou Jiang, Hao-liang Yuan, Jing-shan Miao, Xin Chen, Shan-shan Ning, Hua Xiang, Yu-meng Guo, Ming Yan, Lu-yong Zhang
• Journal: Acta pharmacologica Sinica (Acta Pharmacol Sin) Vol. 35 Issue 8 Pg. 1082-92 (Aug 2014) ISSN: 1745-7254 [Electronic] United States
• PMID: 25047514 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Aromatase Inhibitors
• Flavonoids
• Quinolines
• Small Molecule Libraries
• Aromatase

Topics

• Aromatase (chemistry, metabolism)
• Aromatase Inhibitors (chemistry, pharmacology)
• Breast (drug effects, enzymology)
• Breast Neoplasms (drug therapy, enzymology)
• Cell Line, Tumor
• Cell Proliferation (drug effects)
• Drug Screening Assays, Antitumor (methods)
• Female
• Flavonoids (chemistry, pharmacology)
• High-Throughput Screening Assays (methods)
• Humans
• Molecular Docking Simulation
• Quinolines (chemistry, pharmacology)
• Small Molecule Libraries (chemistry, pharmacology)
• Spectrometry, Fluorescence (methods)