Researchers Discover Why Mutant Gene Causes Colon Cancer

[Guest guest]

[interesting ... I wonder if supplementation of retinoic acid would

prevent colon cancer in people at risk?]

 

Source: University Of Utah Health Sciences Center

2004-09-10

URL: http://www.sciencedaily.com/releases/2004/09/040910075443.htm

--

 

Researchers Discover Why Mutant Gene Causes Colon Cancer

Mutations in the adenomatous polyposis coli (APC) tumor suppressor gene

have been found to cause 85 percent of colon cancers. Now researchers at

the University of Utah's Huntsman Cancer Institute know why. In a paper

published on-line Sept. 9 in the Journal of Biological Chemistry, they

explain that APC controls the conversion of dietary vitamin A into

retinoic acid. If this process is impaired, colon cancer can result.

 

" For a long time, scientists believed they knew what the APC gene did –

that it regulated cell growth and division – but now we know we've been

missing a big piece of the picture, " reports David Jones, Ph.D.,

principal investigator of the study and leader of HCI's Colon Cancer

Scientific Program. " What we didn't know was that it converts vitamin A

into retinoic acid, which is vital for normal colon cell development. "

 

Jones' lab had recently demonstrated that lack of retinoic acid, induced

by mutating the APC gene, led to cancerous tumors in human colon cell

lines. The new study blocked APC function in zebrafish and demonstrated

that when the APC gene was blocked, the fish embryos lacked normal

intestinal lining cells. When the embryos were treated with retinoic

acid, normal cell development was restored. Because zebrafish and humans

share many genes, including the APC gene, researchers often use the

little black-and-white striped fish as models to study various aspects

of human development.

 

" Implications of this study are far reaching, " Jones says. " We have long

suspected that vitamin A was helpful in preventing certain cancers,

including colon cancer. With this new understanding, it may be possible

to bypass a non-functioning APC gene by introducing retinoids as a form

of chemoprevention, and thus control the undifferentiated and

uncontrolled growth of colon cells that results in colon cancer. "

 

Several years ago, University of Utah researchers identified the APC

gene, as well as an inherited colon cancer predisposition known as

familial adenomatous polyposis (FAP) that occurs in people who have APC

mutations. In this inherited syndrome, hundreds to thousands of

pre-cancerous growths called adenomatous polyps form in the colon,

usually beginning before a person is 16 years old. The lifetime risk for

people with this inherited mutation is 100 percent. Scientists have

since determined that an acquired mutation of the APC gene is also found

in 85 percent of sporadic colon cancer. Colon cancer is the number two

cancer killer in the United States.

 

 

Jones is an associate professor in the Department of Oncological

Sciences at the University of Utah School of Medicine. HCI researchers

Lincoln Nadauld, M.D., Ph.D.; Imelda Sandoval; Stephanie Chidester; and

H. Joseph Yost, Ph.D., were contributors to the study, which was funded

by grants from the American Cancer Society and the National Cancer

Institute.

 

Huntsman Cancer Institute's mission is to understand cancer from its

beginnings, to use that knowledge in the creation and improvement of

cancer treatments, to relieve the suffering of cancer patients, and to

provide education about cancer risk, prevention, and care.

 

 

--

 

This story has been adapted from a news release issued by University Of

Utah Health Sciences Center.

[Guest guest]

It's troubling that we didn't get a definitive statement about this question

from the researchers. How can it be interpreted to mean anything but that

we should supplement with retinoic acid? Can't it be taken for granted that

we're deficient in nutritional factors that defend against this deadly

cancer, especially considering its high incidence? We need to talk to the

most celebrated figures in alternative medicine about this study, and hear

what they have to say about supplementing with retinoic acid.

JP

 

-

" David Elfstrom " <listbox

 

Friday, September 10, 2004 12:31 PM

Researchers Discover Why Mutant Gene

Causes Colon Cancer

 

 

[interesting ... I wonder if supplementation of retinoic acid would

prevent colon cancer in people at risk?]

 

Source: University Of Utah Health Sciences Center

2004-09-10

URL: http://www.sciencedaily.com/releases/2004/09/040910075443.htm

----------

----

 

Researchers Discover Why Mutant Gene Causes Colon Cancer

Mutations in the adenomatous polyposis coli (APC) tumor suppressor gene

have been found to cause 85 percent of colon cancers. Now researchers at

the University of Utah's Huntsman Cancer Institute know why. In a paper

published on-line Sept. 9 in the Journal of Biological Chemistry, they

explain that APC controls the conversion of dietary vitamin A into

retinoic acid. If this process is impaired, colon cancer can result.

 

" For a long time, scientists believed they knew what the APC gene did –

that it regulated cell growth and division – but now we know we've been

missing a big piece of the picture, " reports David Jones, Ph.D.,

principal investigator of the study and leader of HCI's Colon Cancer

Scientific Program. " What we didn't know was that it converts vitamin A

into retinoic acid, which is vital for normal colon cell development. "

 

Jones' lab had recently demonstrated that lack of retinoic acid, induced

by mutating the APC gene, led to cancerous tumors in human colon cell

lines. The new study blocked APC function in zebrafish and demonstrated

that when the APC gene was blocked, the fish embryos lacked normal

intestinal lining cells. When the embryos were treated with retinoic

acid, normal cell development was restored. Because zebrafish and humans

share many genes, including the APC gene, researchers often use the

little black-and-white striped fish as models to study various aspects

of human development.

 

" Implications of this study are far reaching, " Jones says. " We have long

suspected that vitamin A was helpful in preventing certain cancers,

including colon cancer. With this new understanding, it may be possible

to bypass a non-functioning APC gene by introducing retinoids as a form

of chemoprevention, and thus control the undifferentiated and

uncontrolled growth of colon cells that results in colon cancer. "

 

Several years ago, University of Utah researchers identified the APC

gene, as well as an inherited colon cancer predisposition known as

familial adenomatous polyposis (FAP) that occurs in people who have APC

mutations. In this inherited syndrome, hundreds to thousands of

pre-cancerous growths called adenomatous polyps form in the colon,

usually beginning before a person is 16 years old. The lifetime risk for

people with this inherited mutation is 100 percent. Scientists have

since determined that an acquired mutation of the APC gene is also found

in 85 percent of sporadic colon cancer. Colon cancer is the number two

cancer killer in the United States.

 

 

Jones is an associate professor in the Department of Oncological

Sciences at the University of Utah School of Medicine. HCI researchers

Lincoln Nadauld, M.D., Ph.D.; Imelda Sandoval; Stephanie Chidester; and

H. Joseph Yost, Ph.D., were contributors to the study, which was funded

by grants from the American Cancer Society and the National Cancer

Institute.

 

Huntsman Cancer Institute's mission is to understand cancer from its

beginnings, to use that knowledge in the creation and improvement of

cancer treatments, to relieve the suffering of cancer patients, and to

provide education about cancer risk, prevention, and care.

 

 

----------

----

 

This story has been adapted from a news release issued by University Of

Utah Health Sciences Center.

[Guest guest]

Question:

What *behavior * made the gene mutate in the first place....? What family

behaviors kept the *damaged* gene reoccurring? Such as chemicals/ foods,

radiation, etc. What stole the vitamin A from the territory? NG

 

-

" David Elfstrom " <listbox

 

Friday, September 10, 2004 3:31 PM

Researchers Discover Why Mutant Gene

Causes Colon Cancer

 

 

[interesting ... I wonder if supplementation of retinoic acid would

prevent colon cancer in people at risk?]

 

Source: University Of Utah Health Sciences Center

2004-09-10

URL: http://www.sciencedaily.com/releases/2004/09/040910075443.htm

----------

----

 

Researchers Discover Why Mutant Gene Causes Colon Cancer

Mutations in the adenomatous polyposis coli (APC) tumor suppressor gene

have been found to cause 85 percent of colon cancers. Now researchers at

the University of Utah's Huntsman Cancer Institute know why. In a paper

published on-line Sept. 9 in the Journal of Biological Chemistry, they

explain that APC controls the conversion of dietary vitamin A into

retinoic acid. If this process is impaired, colon cancer can result.