Even healthy-looking smokers have early cell damage which destroys necessary genetic programming

July 16, 2013

Smokers who've received a clean bill of health from their doctor may believe cigarettes haven't harmed their lungs. However, researchers at Weill Cornell Medical College have found that even smokers who seem healthy have damaged airway cells, with characteristics similar to cells found in aggressive lung cancer.

The study, published today in the journal Stem Cell, compared that line the airway from healthy nonsmokers with those from smokers with no detectable lung disease. The smokers' cells showed early signs of impairment, similar to that found in lung cancer—providing evidence that smoking causes harm, even when there is no that anything is wrong.

"The study doesn't say these people have cancer, but that the cells are already starting to lose control and become disordered," says the study's senior investigator, Dr. Ronald G. Crystal, chairman and professor of at Weill Cornell Medical College. "The smoker thinks they are normal, and their doctor's exam is normal, but we know at the biologic level that all ' lungs are abnormal to some degree."

The researchers found that in the cells lining the airways of the smokers's lungs, genes had been turned on. These are genes that are normally expressed in developing embryos—soon after eggs are fertilized—before cells are programmed with their specific assignment. This gene is also "on" in the most aggressive, hard-to-treat lung cancers.

"We were surprised to see that the smokers were expressing these very primitive human embryonic stem cell genes," Dr. Crystal says. "These genes are not normally functioning in the healthy lung."

Healthy , like all of the body's cells, have very specific assignments. Although all of the body's cells contain the same genes, genes are only "turned on" for each cell's defined task. Therefore, healthy lung cells only express genes related to lung function, while express brain-specific genes. "Healthy cells are very tightly controlled. Normal cells have rules and only do certain things," says Dr. Crystal. "In cancer, that control is lost."

This loss of control allows cancerous cells to multiply without restraint and enables them to migrate to other organs because the genetic programming that keeps them on task is in disarray. The study found that smokers' cells were in the very early stages of losing this control.

"When you smoke a cigarette, some of the genetic programming of your lung cells is lost," says Dr. Crystal. "Your cells take on the appearance of a more primitive cell. It doesn't necessarily mean you will develop cancer, but that the soil is fertile to develop cancer."

In the study, 21 healthy were compared to 31 smokers who had no lung disease symptoms and had normal X-rays as well as normal chest examinations. All individuals were evaluated at Weill Cornell's Clinical and Translational Science Center and Department of Genetic Medicine Clinical Research Facility. By sending a thin tube called a bronchoscope and a fine brush into the lungs, investigators gently brushed the inside of the airways to collect cells from the airway's lining. Researchers examined these cells, called the airway epithelium, which come into contact with cigarette smoke and are where cancer begins, Dr. Crystal says.

Routine checkups can mislead smokers into thinking cigarettes aren't hurting their bodies. However, these results paint a different picture. "Physical examinations, tests and chest x-rays are not sensitive enough to pick up these very early changes," Dr. Crystal warns doctors and . "The take-home message is: Don't smoke. Smoking is bad and if you smoke, you're at risk."

Additional studies are needed to determine why exposure to smoke causes these changes, so that researchers can pinpoint particular areas for designing treatments. "This study gives us clues about how cells look on the way to developing lung cancer, which can help us develop therapies," Dr. Crystal says.

Beyond treatments, Dr. Crystal also hopes the research can lay the foundation for lung cancer prevention. Smoking is an addiction, he says, and despite high taxes and ads describing the dangers, 20 percent of the population continues to smoke. "Eventually, the goal is to develop therapies to protect the airways from cigarettes and other pollutants," Dr. Crystal says. "Understanding these very early events will give us clues and help us develop ways to protect the lungs."

Explore further: Precancer markers identified in airway epithelium cells of healthy smokers

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VendicarE
not rated yet Jul 16, 2013
Bullshit.

According to the Heritage Foundation, Smoking is a healthy lifestyle CHOICE that children should think carefully about.

What is freedom without choice?

Having more CHOICE can never be bad and hence it follows logically that the choice to smoke can never be bad so this scientific research is nothing but a scam and a fraud perpetrated by Luciferian Statists.
MrKool
not rated yet Jul 16, 2013
There is no proof smoking causes cancer. In my mind its the biggest hoax in history. Govt wants more control, less freedom of choice and higher taxes. Medical researchers need grants so they just report what the govt wants to hear otherwise their funding is cut off. Wake up! People have been dying for thousands of years without the help of cigarettes. Death is just part of the natural cycle of the planet!
langbaba
not rated yet Jul 17, 2013
BUT - smoking stinks! In more ways than one!
It IS bad for you. It IS bad for your kids! Anyone want to disagree on that???

Coffee is probably bad for you too but at least does not stink!

Morons that buy stuff from these companies! An now you blame governments for wanting to make money?

Hell! Why we are at it, let's sell drugs to whoever wants to buy them! It is a choice after-all ...

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