Galeterone

• CAT Number: I005114
• CAS Number: 851983-85-2
• Molecular Formula: C26H32N2O
• Molecular Weight: 388.55
• Purity: ≥95%
• Synonyms: (3S,8R,9S,10R,13S,14S)-17-(benzimidazol-1-yl)-10,13-dimethyl-2,3,4,7,8,9,11,12,14,15-decahydro-1H-cyclopenta[a]phenanthren-3-ol
• InChI: InChI=1S/C26H32N2O/c1-25-13-11-18(29)15-17(25)7-8-19-20-9-10-24(26(20,2)14-12-21(19)25)28-16-27-22-5-3-4-6-23(22)28/h3-7,10,16,18-21,29H,8-9,11-15H2,1-2H3/t18-,19-,20-,21-,25-,26-/m0/s1
• InChIKey: PAFKTGFSEFKSQG-PAASFTFBSA-N
• SMILES: CC12CCC(CC1=CCC3C2CCC4(C3CC=C4N5C=NC6=CC=CC=C65)C)O

Galeterone (TOK-001) is a multifunctional antiandrogen and CYP17 inhibitor (IC50=47 nM) in castration resistant prostate cancer (CRPC).
Galeterone (TOK-001) affords strong CYP17 lyase inhibition, with IC50 of 47 nM[1]. Galeterone (TOK-001) is both a CYP17A1 inhibitor and androgen receptor antagonist and the similarity of these binding modes is likely the reason for this dual mechanism of action.This CYP17A1 binds abiraterone and Galeterone (TOK-001) with absorbance decreases at 402 nm and increases at 424 nm, consistent with nitrogen binding to the heme iron (type II interaction) with Kd of <100 nM[2]. When LNCaP cells are cultured in medium supplemented with charcoal-stripped serum (CSS, T<1 nM) followed by treatment with increasing concentrations of Galeterone (TOK-001), the steady-state levels of AR protein are markedly decreased (up to 84%, 15 μM Galeterone (TOK-001)). In LAPC-4 cells, abiraterone alcohol reduced AR expression to a greater extent than Galeterone (TOK-001) at concentrations greater than or equal to 1 μM. When LNCaP cells are treated with 20 μM TOK-001 for 24 h, AR mRNA levels are reduced by 38%[3].
Mice inoculated with LAPC-4 tumors are treated subcutaneously with 0.15 mmol/kg of Galeterone (TOK-001) twice daily. Mice treated with TOK-001 have smaller average tumor volume on day 31 when compared to control (p= 0.0001). Galeterone (TOK-001) treatment also significantly reduces the growth rate of tumor growth compared to control (p<0.0001). Upon excision, final tumor weights are also significantly reduced in animals treated with Galeterone (TOK-001) compared to animals treated with control, and castration (p<0.05)[1].

Reference

[1]. Bruno RD, 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.Steroid
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[2]. DeVore NM, et al. Structures of cytochrome P450 17A1 with prostate cancer drugs abiraterone and TOK-001.Nature. 2012 Jan 22;482(7383):116-9.
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[3]. Soifer HS, et al. Direct regulation of androgen receptor activity by potent CYP17 inhibitors in prostate cancer cells.J Biol Chem. 2012 Feb 3;287(6):3777-87. Epub 2011 Dec 15.
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