Arsenic for cancer?

[Guest guest]

Main stream news story. Sounds like more chemo desperation. However,

using low-levels might have a different effect, as did the lead in

ancient Egyptian cosmetics . . .

Arsenic Shows Promise as Cancer Treatment

By _ son-_

(http://www.aolhealth.com/bloggers/catherine-donaldson-evans) Jul 16th

2010 11:32AM

Arsenic usually makes an appearance in murder-mystery poisonings or

fights

against household pests like rats. But in a twist of irony, it may

actually help _cancer_

(http://www.aolhealth.com/condition-center/cancer) patients live.

A form of the poison known as arsenic trioxide, which is already used to

treat a certain _type of leukemia_

(http://www.aolhealth.com/conditions/types-of-leukemia) , is now showing

promise for several other _cancers_

(http://www.aolhealth.com/condition-center/cancer) , according to

researchers at

Stanford University in California.

The scientists learned that combining arsenic with some _medications_

(http://www.aolhealth.com/drugs) may help doctors fight the cancers

formed when a crucial cascade of cells known as the _Hedgehog pathway_

(http://www.cancer.gov/ncicancerbulletin/090809/page6) isn't functioning

properly.

" Arsenic might be especially effective for treating some types of

cancers

in combination with other _drugs_ (http://www.aolhealth.com/drugs) that

act at different levels of the Hedgehog pathway, " said lead author

Philip

Beachy, a professor of developmental biology at Stanford's School of

Medicine.

The paper by Beachy; a postdoctural researcher in his lab, Jynho Kim;

and

their colleagues appears in the July 12 online edition of the

_Proceedings

of the National Academy of Sciences_ (http://www.pnas.org/) .

" Many pharmaceutical companies are developing anticancer _drugs_

(http://www.aolhealth.com/drugs) to inhibit the Hedgehog pathway, "

Beachy wrote.

" However, these compounds target a component of the pathway that can be

mutated with patients then becoming resistant to the therapy. Arsenic

blocks a

different step of the cascade. "

In contrast, when acting as a poison, larger amounts of arsenic smother

a

cell's energy production.

The _Food and Drug Administration_ (http://www.fda.org/) already has

approved arsenic trioxide for use in humans. It's been an effective

component

of promyelocytic _leukemia_

(http://www.aolhealth.com/conditions/leukemia) treatment for about a

decade.

Beachy and his colleagues studied how arsenic trioxide worked in human

and

mouse cells and in laboratory mice with a type of _brain tumor_

(http://www.aolhealth.com/conditions/brain-tumor) called a

medulloblastoma that is

known to be reliant on Hedgehog cell signaling.

Their findings showed that fairly low levels of the toxin, similar to

the

amount approved for use in people suffering from promyelocytic

_leukemia_

(http://www.aolhealth.com/conditions/leukemia) , slowed or stopped tumor

growth in mice.

Administering a combined treatment of arsenic trioxide with a Hedgehog

inhibitor derived from plants called cyclopamine had an even greater

effect.

Drugs that mimic what cyclopamine can do are currently in development.

Dr. Stan Gerson, the director of the University Hospitals Ireland Cancer

Center in Cleveland, called the findings " intriguing " but said human

trials

need to be done before it is known whether arsenic trioxide truly is an

effective cancer-fighting agent in people.

" Whether on a therapeutic scale it can provide enough selective toxicity

is very unclear, " Gerson told AOL Health. " The caution is that the

pre-clinical studies just may not be that predictive of the clinical

outcome. "

More on Cancer:

_U.S. Cancer Rates Dropping, Study Finds_

(http://www.aolhealth.com/2010/07/08/u-s-cancer-death-rates-drop/)