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Activation of Apoptosis by Cytoplasmic Microinjection of Cytochrome c
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Tumour cytochrome P450 and drug activation

L H Patterson1, G I Murray

  • 1Department of Pharmaceutical and Biological Chemistry, The School of Pharmacy, University of London, 9-39 Brunswick Square, London, WC1N 1AX, UK. medchem@ulsop.ac.uk

Current Pharmaceutical Design
|June 8, 2002
PubMed

Insights

Drug-metabolizing cytochrome P450s (CYPs) are found in many cancers, with specific profiles varying by tumor type. Overexpressed CYPs, particularly CYP1B1, offer potential for targeted prodrug activation in cancer therapy.

Area of Science:

  • Pharmacology
  • Oncology
  • Biochemistry

Background:

  • Drug-metabolizing cytochrome P450s (CYPs) are expressed across various human cancers.
  • Distinct CYP profiles exist for individual tumor types, detectable via activity, protein, and mRNA levels.
  • Certain CYPs, notably CYP1B1, are overexpressed in lung, breast, liver, gastrointestinal, prostate, and bladder cancers.

Purpose of the Study:

  • To investigate the role of tumor-specific cytochrome P450 expression in cancer.
  • To explore the potential of leveraging tumor CYP activity for prodrug activation strategies.
  • To highlight existing and novel prodrugs that rely on CYP-mediated activation for anti-tumor effects.

Main Methods:

  • Analysis of CYP expression profiles in different human cancer types.
  • Detection of CYP activity, immunoreactive protein, and mRNA.
  • Retrospective identification of known prodrugs as CYP substrates.
  • Evaluation of novel prodrug designs dependent on tumor CYP activation.

Main Results:

  • Selected CYPs, especially CYP1B1, are significantly overexpressed in multiple tumor types.
  • Several clinically used prodrugs (e.g., cyclophosphamide, Tegafur, flutamide) are CYP substrates, suggesting underestimated tumor CYP activation.
  • New agents designed for selective CYP activation in tumors are being developed, such as 2-(4-aminophenyl)benzothiazoles in CYP1A1 inducible tumors.
  • Bioreductive prodrugs like AQ4N are activated in hypoxic tumor regions via CYP3A.

Conclusions:

  • Tumor-specific CYP expression presents a significant opportunity for targeted cancer prodrug therapy.
  • Exploiting CYP overexpression and activity can enhance the efficacy and selectivity of anti-cancer agents.
  • Future drug development should focus on prodrugs designed for selective activation by tumor-associated CYPs.

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