CYP3A4, CYP2C9 and CYP2B6 expression and ifosfamide turnover in breast cancer tissue microsomes.

Article Details

Citation

Schmidt R, Baumann F, Knupfer H, Brauckhoff M, Horn LC, Schonfelder M, Kohler U, Preiss R

CYP3A4, CYP2C9 and CYP2B6 expression and ifosfamide turnover in breast cancer tissue microsomes.

Br J Cancer. 2004 Feb 23;90(4):911-6. doi: 10.1038/sj.bjc.6601492.

PubMed ID
14970873 [ View in PubMed
]
Abstract

Ifosfamide is a prodrug that requires bioactivation by cytochrome P450 for antitumour activity. Up to now, little is known, to what extent in addition to the liver the ifosfamide metabolism may occur intratumorally. For this purpose, we investigated the expression of CYP3A4, CYP2C9 and CYP2B6 in breast cancer tissue using Western Blotting. Ifosfamide turnover was determined by detection of metabolites of the ifosfamide 4-hydroxylation and N-dechloroethylation in tumour microsomal incubations using HPLC/UV and LC/MS. The results demonstrate that all mammary tumours (n=11) reveal CYP3A4 expression; contents varied from 0.5 to 63 pmol mg(protein)(-1). CYP2C9 (n=9) was present in all tested breast tumour samples, too, while CYP2B6 (n=10) protein could not be detected. All measured breast cancer microsomes (n=4) showed an ifosfamide N-dechloroethylation capacity in the range from 0.04 to 0.21 pmol min(-1) mg(protein)(-1), while metabolites of the 4-hydroxylation could not be determined. In conclusion, the detected presence of CYP3A4 and CYP2C9 in breast tumours offers the possibility of intratumoral turnover of ifosfamide. For the first time in the literature, we could demonstrate a turnover of ifosfamide by microsomal preparations from human breast cancer tissue. A calculated modulation of intratumoral ifosfamide turnover could considerably influence its therapeutic efficiency.

DrugBank Data that Cites this Article

Drug Enzymes
DrugEnzymeKindOrganismPharmacological ActionActions
IfosfamideCytochrome P450 2C9ProteinHumans
Unknown
Substrate
Details
Drug Interactions
DrugsInteraction
Ifosfamide
Thalidomide
The metabolism of Ifosfamide can be increased when combined with Thalidomide.
Ifosfamide
Clozapine
The metabolism of Ifosfamide can be increased when combined with Clozapine.
Ifosfamide
Chlorpromazine
The metabolism of Ifosfamide can be increased when combined with Chlorpromazine.
Ifosfamide
Amprenavir
The metabolism of Ifosfamide can be increased when combined with Amprenavir.
Ifosfamide
Lorlatinib
The metabolism of Ifosfamide can be increased when combined with Lorlatinib.