Printer Friendly

Hitting enzymes to kill cancer cells.

Hitting enzymes to kill cancer cells

Going beyond treating the whole tumor, scientists are looking for fine-tuned drugs that attack the inner workings of cancer cells. Among the latest of these efforts is the inhibition of DNA topoisomerases -- enzymes needed to alter DNA's structure before synthesis of RNA and new DNA can occur. Scientists at the University of Florida in Gainesville are using a computer modeling system to make unique anti-enzyme drugs. And in doing so, they have resurrected a once-abandoned cancer treatment.

Speaking last week at the American Association for Cancer Research's annual meeting in New Orleans, Warren E. Ross said his group compared the structures of drugs already known to inhibit the enzyme topoisomerase II. Discovered within the last decade, the enzyme helps untangle DNA and may direct DNA arrangement in chromosomes (SN: 2/23/85, p.120). From these studies, Ross says, it became apparent the drugs bind first to DNA and then entrap the enzyme. The Florida researchers found that the higher the enzyme concentration, the more potent the drug, and that adding specific chemical groups onto a drug molecule enhances its inhibitory activity.

The researchers also found that a previously tested drug called camptothecin works by inhibiting topoisomerase I -- knowledge that has led to an improved version of the drug. Thus far, Ross says, the new camptothecin has worked well against leukemia and several solid tumors in mice, with "predictable and manageable" toxicities, and without the drug resistance so often developed by cancer cells.
COPYRIGHT 1988 Science Service, Inc.
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 1988, Gale Group. All rights reserved. Gale Group is a Thomson Corporation Company.

Article Details
Printer friendly Cite/link Email Feedback
Author:Edwards, D.D.
Publication:Science News
Date:Jun 4, 1988
Previous Article:Exposing lung cancer as a genetic disease.
Next Article:Flashbulb memories: the picture fades.

Related Articles
Resisting cancer chemotherapy; researchers are struggling to learn how cancer cells survive in the presences of lethal drugs. The aim is to prevent...
Why and wherefores of drug resistance.
Cancer cell's fountain of youth.
Missing enzyme incites cancer debate.
Enzyme erases DNA's molecular coating.
As time goes by, mutant mice face problems.
Infectious Notion.
Drug spares eggs from early death.
Compounds trigger tumor-cell suicide.
Activating cancer drug discovery.

Terms of use | Copyright © 2017 Farlex, Inc. | Feedback | For webmasters