Gene found that may predict lung cancer in smokers

WASHINGTON Wed Apr 7, 2010 6:34pm EDT

1 of 3. An undated handout image of cells obtained by airway brushing.

Credit: Reuters/Avrum Spira/Handout

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WASHINGTON (Reuters) - Researchers have identified a group of genes that are especially active in lung cancer patients -- even in healthy tissue -- and said they may be used to predict which smokers will eventually develop lung cancer.

And, they said, a natural supplement derived from food that is being tested to prevent lung cancer appears to halt the precancerous changes.

"Even in normal cells or premalignant cells prior to cancer development we see this pathway being turned on," said Andrea Bild of the University of Utah, who worked on the study published in the journal Science Translational Medicine.

The main gene is called PI3K and it affects a pathway of other genes, Bild, Avrum Spira of Boston University and colleagues reported. And it can be found in the windpipes of smokers, meaning they do not need more dangerous and uncomfortable lung tests.

"These cells are like a canary in the coal mine," Spira said in a telephone interview. "Even though lung cancer develops deep down in your lungs when you smoke, these cells can tell you whether you are on the way to developing lung cancer. It is sort of a window into the lung."

Cigarette smoke causes 90 percent of all cases of lung cancer, which kills 1.2 million people a year globally.

But only about 10 percent of smokers ever develop lung cancer, although they often die of other causes such as heart disease, stroke or emphysema.

Spira and Bild put together results from two ongoing trials of smokers.

"The patients walk in the door and they have something wrong with them -- we don't know what. Maybe they have lung cancer, maybe they have something else," Bild said in a telephone interview.

Lung cancer is so deadly precisely because it causes vague symptoms. Most patients are not diagnosed until it has spread and can no longer be treated.

ACTIVE GENES

The researchers used a brush to collect cells from the windpipes of the smokers. They put these on a gene chip or microarray to see which genes were active in the cells.

"We found this certain pathway, PI3K, was turned on in patients that had lung cancer as opposed to patients that had other problems," Bild said.

PI3K had long been suspected in lung cancer. But another experiment got the researchers more excited.

These were patients with precancerous lesions in their lungs called dysplasia. PI3K was also active in their lesions.

And the second group was taking the natural supplement, myo-inositol, to try to prevent lung cancer. In the patients whose lesions shrank after taking the supplement, PI3K also became less active, the researchers found.

"Together it gives us the story of the importance of this pathway," Bild added. "Whether it is going to save millions of people, who knows?"

Spira said he is working with Boston-based Allegro Diagnostics, which is halfway through a 60-patient clinical trial of the test.

The researchers have patented their findings through the universities but Bild said myo-inositol supplements are cheap and freely available.

Myo-inositol is also found in fruits, beans, grains and nuts, although Bild said the finding does not necessarily explain why people who eat more of these foods have a lower risk of cancer in general.

(Editing by John O'Callaghan)

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Comments (5)
teri1276 wrote:
And how can we know whether we have it. Are they developing any relevant test to be available to the public???

Apr 08, 2010 10:37am EDT  --  Report as abuse
Anonmucker wrote:
Great. More DNA sequences, more patents, more statistical probabilities, more drugs (recommended to be taken daily), more preemptive, invasive surgery – all while healthy and without any symptoms.

Apr 08, 2010 2:15pm EDT  --  Report as abuse
Carol2000 wrote:
What they’re testing for is actually a sign of virus infection.

The pivotal role of phosphatidylinositol 3-kinase–Akt signal transduction in virus survival. S Cooray. J Gen Virol 2004;85:1065-1076. A number of viruses including EBV, HPV, HBV and HCV have the ability to establish long-term infections in the host, either through the establishment of latent or chronic infections, which can ultimately lead to cellular transformation. It appears that the gene products of these viruses stimulate PI3K–Akt-mediated cell survival and thereby block apoptosis of the cells they infect. This contributes to both virus survival and oncogenic transformation (Fig. 2, Table 1). However, activation of this pathway is not only required for viral transformation but also for other stages of the virus life cycle. EBV BZLF1-mediated reactivation from latency, for example, requires the activation of PI3K and Akt. Productive polyomavirus infection requires the up-regulation of PI3K–Akt cell survival and cellular proliferation.”

http://vir.sgmjournals.org/cgi/content/full/85/5/1065

And among that list of viruses, HPV is implicated in at least a quarter of non-small cell lung cancers. The Surgeon General et al. are guilty of fraud for ignoring the role of HPV in order to falsely blame smoking and passive smoking.

http://www.smokershistory.com/hpvlungc.htm

See how mass media propaganda leaves out the most important facts!

Apr 08, 2010 5:46pm EDT  --  Report as abuse
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