SB, Here's another retinoid article on reversing lung damage from smoking (but retinoids were not mentioned):
Study: Smoking Permanently Raises Lung
Cancer Risk
By LEIGH HOPPER
c. 1997 Cox News Service
AUSTIN, Texas -- Austin resident Jim Spiller took up smoking as
an 11-year-old kid in Baton Rouge, La. He puffed his way through the
Navy during the Vietnam War, buying cigarettes for 10 cents a pack.
He quit at age 35 - a feat he says is one of his life's greatest
achievements - and took up exercise.
Now 51, the state employee considers himself to be in excellent
physical shape. But are his lungs?
A study at the University of Texas Southwestern Medical Center at
Dallas suggests smoking causes permanent, genetic damage in the
lungs, raising the risk of lung cancer forever, even in people who stop.
``We always knew smoking was bad, but we didn't realize quite how
bad it was and ... how long the damage persisted after smoking
stopped,'' said Dr. Adi Gazdar, a professor of pathology.
The good news is, the findings may pave the way for drugs, called
chemoprevention agents, that actually reverse lung tissue damage on
the molecular level.
Gazdar emphasized that the study shouldn't discourage anyone from
quitting. The smoker who quits lowers the risk simply by not adding
more damage to what's already there.
Gazdar and his colleagues studied lung tissue from 63 current
smokers, former smokers and nonsmokers. In both the current and
former smokers, they detected genetic changes commonly found in
lung cancer tumors in noncancerous lung tissue. Lung tissue from
lifetime nonsmokers showed no genetic alterations.
Results of the study, which appear this week in the Journal of the
National Cancer Institute, confirm similar findings this summer by the
University of Pittsburgh and University of Texas M.D. Anderson
Cancer Center in Houston.
Scientists have long believed that smokers who quit are at a higher risk
for lung cancer than people who have never smoked. In fact, more
than 50 percent of new lung cancers occur in former smokers.
Now scientists are beginning to understand why this might be so.
``My belief is, and this is only hypothesis, you need many, many
(molecular) changes to get lung cancer,'' Gazdar said. ``What we think
happens when you smoke is you get cumulative changes. When you
stop smoking, (the changes) don't go away but the new ones stop
accumulating at the same rate.''
The carcinogens in tobacco smoke alter the genes in the lungs. Over
time, the changes debilitate genes that suppress tumors and fight
cancer, said Dr. Waun Ki Hong, who is doing similar research at
M.D. Anderson. This type of genetic damage is not hereditary, he
said.
Because lung cancer symptoms are elusive, most cases are discovered
in the advanced stage when they are difficult to cure.
Gazdar said he hopes identifying genetic changes, or markers, will
enable researchers to tell which smokers and ex-smokers are at
greatest risk of developing lung cancer.
The markers will also help researchers tell if drugs that prevent or
reverse damage are working. UT Southwestern and M.D. Anderson
are currently testing chemopreventive agents in former smokers.
Spiller said he wants to know just how the changes he made by
quitting smoking have helped.
``I know how long I smoked. ... I know what I did to correct the
damage,'' he said. ``I'd be curious to know if it was effective.''
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(The Cox web site is at coxnews.com )
NYT-09-19-97 1017EDT< |
