TOK-001

In vitro assay of CYP17

The in vitro CYP17 inhibitory activity of Galeterone was evaluated using rapid acetic acid releasing assay, utilizing intact P450c17-expressing E. coli as the enzyme source. It involved the use of [21-3H]-17α-hydroxypregnenolone as the substrate, and CYP17 activity was measured by the amount of tritiated acetic acid formed during the cleavage of the C-21 side chain of the substrate. IC50 value was obtained directly from plots relating percentage inhibition versus inhibitor concentration over appropriate ranges.

Cell lines

LNCaP 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 °C for 10 minutes and/or shake it in the ultrasonic bath for a while. Stock solution can be stored below - 20 °C for several months.

Reacting condition

1 ~ 15 μM; 24 hrs

Applications

Compared with all Galeterone analogues, Galeterone was still the most effective compound in vitro, down-regulating > 95% AR at the concentration of 15 μM.

Animal models

Male SCID mice bearing LAPC-4 tumors

Dosage form

0.15 mmol/kg; s.c.; b.i.d., for 31 days

Applications

Galeterone effectively inhibited the average volume of LAPC-4 tumors in SCID mice by more than 80%. After 31 days of Galeterone treatment, the final tumor weight was also significantly reduced by more than 50%.

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.

References:

[1]. Handratta VD, Vasaitis TS, Njar VC, Gediya LK, Kataria R, Chopra P, Newman D Jr, Farquhar R, Guo Z, Qiu Y, Brodie AM. Novel C-17-heteroaryl steroidal CYP17 inhibitors/antiandrogens: synthesis, in vitro biological activity, pharmacokinetics, and antitumor activity in the LAPC4 human prostate cancer xenograft model. J Med Chem. 2005 Apr 21;48(8):2972-84.

[2]. Bruno R D, Vasaitis T S, Gediya L. K, et al. Synthesis and biological evaluations of putative metabolically stable analogs of VN/124-1 (TOK-001): Head to head anti-tumor efficacy evaluation of VN/124-1 (TOK-001) and abiraterone in LAPC-4 human prostate cancer xenograft model. Steroids, 2011,76: 1268-1279.