Glucocorticoid receptor (GR) antagonist activity, Progesterone receptor (PR) antagonist activity

T47D alkaline phosphatase assay: T47D human breast cancer cells are plated in 96-well tissue culture plates at 104 cells per well in assay medium [RPMI medium without phenol red containing 5% (v/v) charcoal-treated FBS and 1% (v/v) penicillin–streptomycin]. Two days later, the medium is decanted and Mifepristone or control is added at a final concentration of 0.1% (v/v) dimethylsulfoxide in fresh assay medium. Twenty-four hours later, an alkaline phosphatase assay is performed using a SEAP kit. The medium is decanted and the cells are fixed for 30 minutes at room temperature with 5% (v/v) formalin. The cells are washed once at room temperature with Hanks' buffered saline solution. Equal volumes (0.05 mL) of dilution buffer, assay buffer, and 1:20 substrate/enhancer mixture are then added. After 1-hour incubation in the dark at room temperature, the lysate is transferred to a white 96-well plate and luminescence is read using a LuminoSkan Ascen. A549 reporter assay: A549 human lung carcinoma cells are washed with OPTI-MEM I. The medium is removed and lipid–DNA complex solution (1.5 μg/mL of GRE-luciferase reporter DNA in 8.5 mL OPTI-MEM I plus 6 μL/mL DMRIE-C reagent in 8.5 mL OPTI-MEM I, combined, mixed and incubated at room temperature for 40 minutes) is overlayed onto the cells in a T160 flask. The cells are incubated for 16 hours at 37 ℃ in a CO2 incubator. The DNA-containing medium is removed and 30 mL of growth medium containing 5% (v/v) charcoal-treated fetal bovine serum is added. After 5-6 hours, the cells are seeded in 96-well plates and incubated overnight at 37 ℃. Mifepristone is then added to each well followed by dexamethasone as a corticoid challenge. The cells are incubated for 24 hours. Luciferase assay buffer is added to each well and the cells are incubated for 30 minutes at room temperature. Luciferase activity is measured in a DYNEX Microlite plate on a TopCount.

Cell lines

Sperm; ovarian cancer cell lines(SK-OV-3, Caov-3, IGROV-1, and OV2008 cells)

Preparation method

The solubility of this compound in DMSO is >10 mM. General tips for obtaining a higher concentration: Please warm the tube at 37℃ for 10 minutes and/or shake it in the ultrasonic bath for a while. Stock solution can be stored below -20℃ for several months.

Reacting condition

0.04, 0.4, 4 and 40 μM for 1 h; or 20 μM for 1-3 days

Applications

Mifepristone modulated human sperm functions and dose-dependently inhibited progesterone-induced acrosome reaction, hyperactivation and [Ca2+]i in human spermatozoa [2]. Moreover, mifepristone suppressed cell growth and decreased the expression of the S phase cyclin (cyclin A) and the M phase cyclin (cyclin B1) in various ovarian cancer cell lines [3].

Animal models

SK-OV-3 tumor xenografts model

Dosage form

0.5, 1.0 mg/d, s.c., for 40 days

Applications

Mifepristone (0.5, 1.0 mg/d) dose-dependently inhibited SK-OV-3 tumors growth in nude mice [3].

Other notes

Please test the solubility of all compounds indoor, and the actual solubility may slightly differ with the theoretical value. This is caused by an experimental system error and it is normal.

Mifepristone (RU486) is a potent antagonist of progesterone receptor, used as a contraceptive agent [1].

As a contraceptive agent, Mifepristone has been reported to reduce the size of uterine fibroids, and inhibit the growth of meningioma cells in vitro, in experimental animal models and in patients with inoperable meningiomas. As a non-contraceptive action, Mifepristone was been revealed to inhibit the proliferation of normal and malignant endometrial cells, breast cancer cells, prostate cancer cells and gastric adenocarcinoma cell lines. In addition, Mifepristone has been demonstrated to have progesterone-like effects and suppression ovarian cancer cell growth in a dose-dependent fashion with the IC50 values of 6.25μmol/l and 6.91μmol/l for SK-OV-3 and OV2008 cell lines, respectively [1].

References:
[1] Goyeneche AA1, Carón RW, Telleria CM. Mifepristone inhibits ovarian cancer cell growth in vitro and in vivo. Clin Cancer Res. 2007 Jun 1; 13(11):3370-9.