Skip to main content
padlock icon - secure page this page is secure

Bioactivation of Quinones by DT-diaphorase, Molecular, Biochemical, and Chemical Studies

Buy Article:

$46.00 + tax (Refund Policy)

Abstract

Because of the elevated DT-diaphorase (DTD) activity in certain tumors such as human nonsmall cell lung cancer (NCSLC), DTD is a potential target on which to base the development of new antitumor compounds. Mitomycin C is the most effective single agent used for the therapy of NSCLC and is metabolized and bioactivated by DTD. Mitomycin C is a poor substrate for DTD, however, and its metabolism is pH-dependent. We have therefore focused on identifying more efficient substrates for DTD. We have developed a metabolic and cytotoxicity screen that identifies compounds which are efficiently bioactivated by DTD. This screen utilizes both aerobic and hypoxic conditions and cell lines with both elevated and deficient DTD activity as an index of selectivity. Using the screen described above, we have identified [3-hydroxy-5-aziridinyl-1-methyl-2-(1H-indole-4,7-indione)-prop-β-en-α-ol] (E09), 2,5-diaziridinyl-1,4-benzoquinone (MeDZQ), and streptonigrin as compounds that are most efficiently bioactivated by DTD and exert selective cytotoxicity. Although certain tumors such as NSCLC have elevated DTD activity, we have characterized a point mutation at position 609 in the DTD cDNA, which codes for a proline to serine change in the protein and leads to a loss of enzyme activity. We have characterized this mutation in both BE human colon carcinoma cells and HS96 human NSCLC cells. This mutation and resulting lack of DTD activity complicates the use of agents designed to target DTD in tumors. An enzyme-directed approach to chemotherapy utilizing DTD as a target is still a viable strategy, however, providing that pretreatment biopsies can be obtained and screened for DTD activity.
No References
No Citations
No Supplementary Data
No Article Media
No Metrics

Keywords: DT-diaphorase; antitumor quinones; drug development; gene expression; mitomycin C; mutation

Document Type: Commentary

Publication date: January 1, 1994

More about this publication?
  • Formerly: Oncology Research Incorporating Anti-Cancer Drug Design
    Oncology Research Featuring Preclinical and Clincal Cancer Therapeutics publishes research of the highest quality that contributes to an understanding of cancer in areas of molecular biology, cell biology, biochemistry, biophysics, genetics, biology, endocrinology, and immunology, as well as studies on the mechanism of action of carcinogens and therapeutic agents, reports dealing with cancer prevention and epidemiology, and clinical trials delineating effective new therapeutic regimens.

    From Volume 23, Oncology Research Featuring Preclinical and Clinical Cancer Therapeutics is Open Access under the terms of the Creative Commons CC BY-NC-ND license.

  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed content
  • Free trial content
Cookie Policy
X
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more