Human sterol 14α-demethylase as a target for anticancer chemotherapy: towards structure-aided drug design.
Rapidly multiplying cancer cells synthesize greater amounts of cholesterol to build their membranes. Cholesterol-lowering drugs (statins) are currently in clinical trials for anticancer chemotherapy. However, given at higher doses, statins cause serious side effects by inhibiting the formation of other biologically important molecules derived from mevalonate. Sterol 14α-demethylase (CYP51), which acts 10 steps downstream, is potentially a more specific drug target because this portion of the pathway is fully committed to cholesterol production. However, screening a variety of commercial and experimental inhibitors of microbial CYP51 orthologs revealed that most of them (including all clinical antifungals) weakly inhibit human CYP51 activity, even if they display high apparent spectral binding affinity. Only one relatively potent compound, (R)-N-(1-(3,4'-difluorobiphenyl-4-yl)-2-(1H-imidazol-1-yl)ethyl)-4-(5-phenyl-1,3,4-oxadiazol-2-yl)benzamide (VFV), was identified. VFV has been further tested in cellular experiments and found to decrease proliferation of different cancer cell types. The crystal structures of human CYP51-VFV complexes (2.0 and 2.5 Å) both display a 2:1 inhibitor/enzyme stoichiometry, provide molecular insights regarding a broader substrate profile, faster catalysis, and weaker susceptibility of human CYP51 to inhibition, and outline directions for the development of more potent inhibitors.
Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232.
Tatiana Y
TY
Hargrove
Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232.
Laura
L
Friggeri
Synchrotron Research Center, Life Science Collaborative Access Team, Northwestern University, Argonne, IL.
Zdzislaw
Z
Wawrzak
Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232.
Suneethi
S
Sivakumaran
Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232.
Eugenia M
EM
Yazlovitskaya
Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232.
Scott W
SW
Hiebert
Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232.
F Peter
FP
Guengerich
Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232.
Michael R
MR
Waterman
Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232 galina.i.lepesheva@vanderbilt.edu.
Galina I
GI
Lepesheva
D058888:14-alpha Demethylase Inhibitors / Q000737:chemistry*; D000935:Antifungal Agents; D000970:Antineoplastic Agents / Q000737:chemistry*; D000981:Antiprotozoal Agents / Q000737:chemistry; D020134:Catalytic Domain; D045744:Cell Line, Tumor; D002775:Cholestadienols / Q000737:chemistry; D018360:Crystallography, X-Ray; D015195:Drug Design; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D006860:Hydrogen Bonding; D007810:Lanosterol / Q000737:chemistry; D008958:Models, Molecular; D011485:Protein Binding; D000072756:Protein Conformation, alpha-Helical; D058886:Sterol 14-Demethylase / Q000737:chemistry*
D058888:14-alpha Demethylase Inhibitors; D000935:Antifungal Agents; D000970:Antineoplastic Agents; D000981:Antiprotozoal Agents; C548418:CYP51A1 protein, human; D002775:Cholestadienols; D007810:Lanosterol; C008693:obtusifoliol; D058886:Sterol 14-Demethylase
X-ray crystallography; cancer; cholesterol; cholesterol/biosynthesis; drug therapy/hypolipidemic drugs; cytochrome P450; enzymology/enzyme mechanisms; inhibition; membranes