Scientists studying brain-wasting diseases linked to mad cow have warned that a new class of cancer drugs have the potential to set off similar brain deterioration.

The new cancer-treatment compounds, known as proteasome inhibitors, block cell machinery used to digest unwanted proteins. But the researchers, led by Susan Lindquist, a professor at the Massachusetts Institute of Technology, said using such compounds in mice helped produce brain-wasting symptoms.

Drugs in the class include Velcade, which is being tested in patients by Millennium Pharmaceuticals, Cambridge, Mass., and the National Cancer Institute. David Schenkein, vice president for clinical oncology at Millennium Pharmaceuticals, said the findings weren't viewed as cause for concern because the drug isn't able to cross into the brain.

[Karl Note:  You can be certain that some adverse publicity on a drug under development by some drug company will be met with denials of applicability by the company. You can also be hopefully sure that a vigorous core of media journalists will sniff out these negative reports to keep the public informed -- the drug companies will certainly NOT publicize these reports -- but will hide them if they can.]

Millennium's is the only proteasome-inhibitor cancer drug to enter human tests, said John Wright, a senior clinical investigator at the National Cancer Institute. The federal cancer institute said it had 28 studies with the drug ongoing in different types of cancer.

After learning of the possible risk, the NCI held several meetings during the summer with experts in prion disease and from the Food and Drug Administration, said Louise Grochow, a senior manager at the National Cancer Institute. Dr. Grochow said the risk was deemed small, and that no significant changes would be made to the design of the studies. However, she added that the NCI would require more thorough neurological evaluation of patients. "So far, there is no evidence that the risk is being played out," said Dr. Grochow.

Proteasome inhibitors aren't the same as protease inhibitors, drugs that are used widely to treat HIV infection and AIDS.

Dr. Lindquist and co-workers found the proteasome effect while studying the molecular basis of prion diseases, which include mad cow and variants that affect humans and deer.

The diseases have been linked to misshapen prion proteins, which accumulate around nerve cells killed off by the condition. However, Dr. Lindquist reports Friday in the journal Science that normal prion proteins were able to cause nerve degeneration when they were present inside a cell's liquidy interior, or cytoplasm.

The proteins were able to accumulate after the scientists applied proteasome-blocking chemicals to the cells. The proteasome is the cellular machinery that normally digests proteins.

The cause of the brain disease has been a major scientific question, and Dr. Lindquist said her paper suggested a possible explanation, though conclusive proof was lacking. Jiyan Ma of Ohio State University, who carried out much of the work, said it could be that one form of the prion protein causes the symptoms, while another form lets it pass between animals. "We think the transmission and the toxicity are separate," said Dr. Ma.

Write to Antonio Regalado at antonio.regalado@wsj.com²

Updated October 18, 2002 12:48 a.m. EDT

Copyright 2002 Dow Jones & Company, Inc. All Rights Reserved Printing, distribution, and use of this material is governed by your Subscription agreement and Copyright laws. For information about subscribing go to http://www.wsj.com

SUBSCRIBE:  The Wednesday Letter is a free electronic monthly newsletter written and published by Karl Loren.  You can view more than 50 back issues of this publication by clicking here.  The Wednesday Letter subscription list is maintained on a secure server, no name is ever given or sold to anyone, and it is never used except for this Newsletter.  It is automatically published on the Tuesday night just before the first Wednesday of every month.  You can subscribe to this free monthly electronic letter by entering your eMail address and name below.  You will then automatically receive a request for confirmation, sent to whatever address you have entered.  If you do NOT receive this confirmation request, then you will not be subscribed.  There may have been an error with your address and you should resubmit.  The letter is never sent twice to the same address -- so you do not have to worry about a duplicate subscription.  When you receive this confirmation request you must reply to it, or your subscription will not become active.  No one can subscribe your name, and address, without you being notified, and if you get an unwanted notice of subscription you only need to DO NOTHING and the subscription will NOT be active.

REMOVAL:  You can remove yourself from the subscription list in several different ways.  Click here to read about this entire newsletter system.  Every edition of The Wednesday Letter is delivered to your address with YOUR name and address in view on the letter, with a link that allows you to remove THAT name from the subscription list.  If you try to send this removal message from an address different from the one you used to send in your original confirmation, then you will get a warning notice first, sent to the subscription address, asking you to confirm that you want to be removed from the list -- by replying to THAT request for confirmation, you will then be automatically removed.  Thus, no one else can unsubscribe you, from some other computer, without your knowledge.  But, if you send in the unsubscribe notice from the same machine used to receive the Letter, then the removal from the subscription list is automatic.

Personal Message:  When you send a personal message to Karl Loren, you will receive a personal reply as per his instructions.  Karl pledges that every personal message will get a personal answer. When you provide your mail address, we will send you free information including our free catalog and a cassette tape lecture by Karl Loren about heart disease, no charge, by mail, even if outside the US.  You can select particular information you would like to receive, along with the free cassette tape and catalog.

You can reach Vibrant Life in many ways, including by mail to Vibrant Life, 2808 N. Naomi St., Burbank, CA 91504.  Within the US and Canada, use the toll free number:  (800) 523-4521, the local number:  (818) 558-1799, the FAX:  (818) 558-7299, eMail to kimberly@oralchelation.com or any one of the hundreds of message forms throughout the 50 web sites.  Vibrant Life normally ships the same day we get an order.  There are message forms on each of the 100,000+ pages on this and other sites where you can communicate with Vibrant Life.  Check out our companion site, at:  http://www.oralchelation.net where Karl's 2000 page book is published.  Karl Loren is the author and webmaster for this BOOK, as well as for another web site about ORAL CHELATION.  His personal philosophical articles are at PHILOSOPHY. 

Copyright © May 20, 2008 6:24 AM by Karl Loren on behalf of Vibrant Life, ALL RIGHTS RESERVED.  Permission is granted for non-commercial downloading, copying, distribution or redistribution on two conditions:  One, that some form of copyright notice is included in every copy distributed or copied, showing the copyright belonging to Vibrant Life, Burbank, CA, at www.oralchelation.com . The second condition is that the material is not to be used for any purpose contrary to the purposes and objectives of this site.  This permission does not extend to materials on this site which are copyrighted by others.