Fw: Researchers Wipe Out Cancer in Mice ~ AP

[Guest guest]

From: " ilena rose " <ilena@...>

Sent: Wednesday, September 05, 2001 10:09 PM

Subject: Researchers Wipe Out Cancer in Mice ~ AP

> ~~~ Thanks Kathi Pureheart ~~~

>

> Scientists have wiped out tumors in mice using a common virus that

> apparently tricks cancer cells into self-destructing.

>

> It is too early to know if the approach might work in humans. Many

> treatments that look promising in mice prove disappointing when they are

> tested on people.

>

> However, the research sheds light on something scientists have noticed

> for years: Some viruses harm cancer cells but leave normal, healthy

cells

> unscathed.

>

> The research involves a virus that is believed to be harmless to humans,

> and a gene called p53 that normally suppresses tumors. In most cancer

> patients, the p53 gene is defective. The virus apparently zeroes in on

> that flaw.

>

> Beard, a professor of virology at the Swiss Institute for

> Experimental Cancer Research in Epalinges, said his team found that the

> explanation involves an unusual hairpin-like portion of the virus' DNA.

>

> When a cancer cell encounters the virus, it apparently interprets the

> hairpin structure as damage to its own DNA. The cell tries to rid itself

> of the damage and ends up self-destructing.

>

> As part of their research, the Swiss team injected human colon cancer

> cells into a group of laboratory mice, followed by the virus two days

> later. Only two of the 12 rodents later formed tumors.

>

> In mice with existing colon cancer tumors, injections of the virus

> eliminated tumors in six of the 10 rodents.

>

> The findings were reported in Thursday's issue of the journal Nature.

>

> Beard said his team hopes to pinpoint the precise feature on the hairpin

> structure that sends cancer cells to their death. If they can do that, he

> said, it may be possible to specially engineer the virus or even develop

a

> drug mimicking its effects.

>

> The virus tested is one of six known adeno-associated viruses, a group

of

> viruses that are among the smallest that exist. Some of those viruses

have

> been used many times by scientists for gene therapy, in which a virus

> delivers a healthy copy of a gene to a patient. Such experiments have

had

> mixed results.

>

> Cancer researcher Arnold J. Levine, co-discoverer of the p53 gene in

1979

> and president of Rockefeller University in New York, said the Swiss

team's

> approach is a long way off from ever being tried in humans.

>

> He said scientists pursuing therapies using viruses to target the p53

> defect, including gene therapy, all face the same problem: how to

> efficiently deliver the therapy to every cancer cell in the body.

>

> Associated Press © iSyndicate

>

>

>

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