Identification of human reductases that activate the dinitrobenzamide mustard prodrug PR-104A:: A role for NADPH:cytochrome P450 oxidoreductase under hypoxia

被引：70

作者：

Guise, Chris P. ^{[1
]}

Wang, Anderson T. ^{[1
]}

Theil, Anke ^{[1
]}

Bridewell, David J. ^{[1
]}

Wilson, William R. ^{[1
]}

Patterson, Adam V. ^{[1
]}

机构：

[1] Univ Auckland, Auckland Canc Society Res Ctr, Auckland 92019, New Zealand

来源：

BIOCHEMICAL PHARMACOLOGY | 2007年 / 74卷 / 06期

关键词：

oxidoreductase; reductive; metabolism; prodrug; hypoxia; cancer;

D O I：

10.1016/j.bcp.2007.06.014

中图分类号：

R9 [药学];

学科分类号：

1007 ;

摘要：

Hypoxia is a common trait found in many solid tumours and thus represents a therapeutic target with considerable potential. PR-104, a hypoxia-activated prodrug currently in clinical trial, is a water-soluble phosphate ester which is converted in vivo to the corresponding alcohol, PR-104A. This 3,5-dinitrobenzamide-2-nitrogen mustard is activated by reduction to the corresponding 5-hydroxylamine (PR-104H) and 5-amine (PR-104M) in hypoxic cells. The clinical effectiveness of PR-104 will depend in part on the expression of reductases within tumours that can effect this reduction. Here, we evaluate the roles of NADPH:cytochrome P450 oxidoreductase (CYPOR; E.C.1.6.2.4) and NAD(P)H:quinone oxidoreductase (NQ01; E.C.1.6.99.2) as candidate PR-104A reductases. A weak correlation was observed between NQ01 activity and aerobic cytotoxicity in a panel of eight tumour cell lines. However, overexpression of human NQ01 did not increase cytotoxicity of PR-104A or the formation of PR-104H/M, showing that PR-104A is not a substrate for NQ01. Overexpression of human CYPOR did, however, increase the hypoxic cytotoxicity of PR-104A, and its metabolism to PR-104H and PR-104M, demonstrating it to be a PR-104A reductase. To assess the contribution of CYPOR to overall activation of PR-104A in hypoxic SiHa cells, a combination of siRNA transfection and antisense expression were used to suppress CYPOR protein by 91% ( +/- 3%), a phenotype which conferred 45% ( +/- 7%) decrease in cytotoxic potency of PR-104A. Regression analysis of all CYPOR depletion data was found to correlate with cytoprotection and metabolism (p < 0.001). Residual PR-104A reductase activity could be inhibited by the flavoprotein inhibitor diphenyhodonium. We conclude that CYPOR is an important PR-104A reductase, but that other flavoenzymes also contribute to its activation in hypoxic SiHa cells. (C) 2007 Elsevier Inc. All rights reserved.

引用

页码：810 / 820

页数：11

共 59 条

[41]

Ross D, 2004, METHOD ENZYMOL, V382, P115

[42] The relative importance of NADPH:: Cytochrome c (P450) reductase for determining the sensitivity of human tumour cells to the indolequinone EO9 and related analogues lacking functionality at the C-2 and C-3 positions [J].

Saunders, MP ;

Jaffar, M ;

Patterson, AV ;

Nolan, J ;

Naylor, MA ;

Phillips, RM ;

Harris, AL ;

Stratford, IJ .

BIOCHEMICAL PHARMACOLOGY, 2000, 59 (08) :993-996

[43] Establishment of an isogenic human colon tumor model for NQO1 gene expression:: Application to investigate the role of DT-diaphorase in bioreductive drug activation in vitro and in vivo [J].

Sharp, SY ;

Kelland, LR ;

Valenti, MR ;

Brunton, LA ;

Hobbs, S ;

Workman, P .

MOLECULAR PHARMACOLOGY, 2000, 58 (05) :1146-1155

[44]

Siim BG, 1997, ONCOL RES, V9, P357

[45] NEW COLORIMETRIC CYTOTOXICITY ASSAY FOR ANTICANCER-DRUG SCREENING [J].

SKEHAN, P ;

STORENG, R ;

SCUDIERO, D ;

MONKS, A ;

MCMAHON, J ;

VISTICA, D ;

WARREN, JT ;

BOKESCH, H ;

KENNEY, S ;

BOYD, MR .

JOURNAL OF THE NATIONAL CANCER INSTITUTE, 1990, 82 (13) :1107-1112

[46] Aerobic Nitroreduction by Flavoproteins: Enzyme Structure, Mechanisms and Role in Cancer Chemotherapy [J].

Skelly, Jane V. ;

Knox, Richard J. ;

Jenkins, Terence C. .

MINI-REVIEWS IN MEDICINAL CHEMISTRY, 2001, 1 (03) :293-306

[47] PATTERNS OF DISCRIMINATION IN ASSESSMENTS OF THE DEATH-PENALTY - THE CASE OF LOUISIANA [J].

SMITH, MD .

JOURNAL OF CRIMINAL JUSTICE, 1987, 15 (04) :279-286

[48]

Stratford IJ, 1998, ANTI-CANCER DRUG DES, V13, P519

[49] The hypoxic tumour microenvironment and metastatic progression [J].

Subarsky, P ;

Hill, RP .

CLINICAL & EXPERIMENTAL METASTASIS, 2003, 20 (03) :237-250

[50] INHIBITION OF CYTOCHROME-P(450) REDUCTASE BY THE DIPHENYLIODONIUM CATION - KINETIC-ANALYSIS AND COVALENT MODIFICATIONS [J].

TEW, DG .

BIOCHEMISTRY, 1993, 32 (38) :10209-10215

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