Abstract
Cytochrome P450 2J2 (CYP2J2) epoxygenase converts arachidonic acid to four regioisomeric epoxyeicosatrienoic acids (EETs) that exert multiple biological effects in the cardiovascular system and in various human solid cancers. However, it is unknown whether this enzyme is expressed or plays any role in malignant hematological diseases. In this study, we found strong and highly selective CYP2J2 expression in five human-derived malignant hematological cell lines and in leukemia cells from peripheral blood and bone marrow in 36 of 42 patients (86%) with malignant hematologic diseases. Furthermore, increased levels of EETs were detected in urine and blood samples from these patients. Addition of exogenous EET or CYP2J2 overexpression in cultured human-derived malignant hematologic cell lines markedly accelerated proliferation and attenuated apoptosis. Addition of the selective CYP2J2 inhibitor compound 26 (C26; 1-[4-(vinyl) phenyl]-4-[4-(diphenyl-hydroxymethyl)-piperidinyl]-butanone hydrochloride) inhibited cell proliferation and increased apoptosis, an effect that was significantly reversed by EET. CYP2J2 overexpression and exogenous EET activated AMP-activated protein kinase, c-Jun NH2-terminal kinase, and phosphatidylinositol 3-kinase/Akt signaling pathways, and increased epidermal growth factor receptor phosphorylation levels. CYP2J2 overexpression also enhanced malignant xenograft growth, which was efficiently inhibited by oral administration of C26 in Tie2-CYP2J2 transgenic mice and in severe combined immunodeficiency (SCID) xenograft mice. Together, these results suggest that CYP2J2 plays a key role in the pathogenesis of human hematologic malignant diseases. Selective inhibition of CYP2J2 may be a promising therapeutic strategy for these conditions.
Footnotes
This work was supported by the China Natural Science Foundation Committee [Grants 30540087, 30430320]; the 973 Program [Grants 2007CB512004, 2002CB513107]; and the International Project. This work was also supported, in part, by the Intramural Research Program of the National Institutes of Health, National Institute of Environmental Health Sciences [Grant Z01-ES025034].
Article, publication date, and citation information can be found at http://jpet.aspetjournals.org.
doi:10.1124/jpet.110.174805.
↵ The online version of this article (available at http://jpet.aspetjournals.org) contains supplemental material.
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ABBREVIATIONS:
- P450
- cytochrome P450
- EET
- epoxyeicosatrienoic acid
- eNOS
- endothelial nitric-oxide synthase
- RT-PCR
- reverse transcriptase-polymerase chain reaction
- SP600125
- anthra[1–9-cd]pyrazol-6(2H)-one
- MTT
- 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide
- EGFR
- epidermal growth factor receptor
- PI3K
- phosphatidylinositol 3-kinase
- GAPDH
- glyceraldehyde-3-phosphate dehydrogenase
- AMPK
- AMP-activated kinase
- JNK
- c-Jun NH2-terminal kinase
- PD98059
- 2′-amino-3′-methoxyflavone
- LY294002
- 2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one
- AG-1478
- 4-(3′-chloroanilino)-6,7-dimethoxy-quinazoline
- GW9662
- 2-chloro-5-nitrobenzanilide
- WBC
- white blood cell
- 14,15-DHET
- 14,15-dihydroxyeicosatrienoic acid
- C26
- compound 26 [1-[4-(vinyl) phenyl]-4-[4-(diphenyl-hydroxymethyl)-piperidinyl]-butanone hydrochloride]
- DHET
- dihydroxyeicosatrienoic acid
- ELISA
- enzyme-linked immunosorbent assay
- siRNA
- small interfering RNA
- DMSO
- dimethyl sulfoxide
- FITC
- fluorescein isothiocyanate
- PCNA
- proliferating cell nuclear antigen
- TUNEL
- terminal deoxynucleotidyl transferase dUTP nick-end labeling
- PKC
- protein kinase C
- PPAR
- peroxisome proliferator-activated receptor
- SCID
- severe combined immunodeficiency
- BrdU
- 5-bromo-2′-deoxyuridine.
- Received September 7, 2010.
- Accepted October 27, 2010.
- U.S. Government work not protected by U.S. copyright
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