Cells lining the mouth reflect the molecular damage that smoking does to the lining of the lungs, researchers at The University of Texas Anderson Cancer Center report on Sunday at the annual meeting of the American Association for Cancer Research.
Examining oral tissue lining the mouth to gauge cancer-inducing molecular alterations in the lungs could spare patients and those at risk of lung cancer from more invasive, uncomfortable procedures used now, said the research team.
"We are talking about just a brushing inside of the cheek to get the same information we would from lung brushings obtained through bronchoscopy," said the study presenter Manisha Bhutani.
The team examined the oral and lung lining tissue -- called the epithelium -- in 125 chronic smokers enrolled in the study.
The status of two crucial tumor-suppressing genes was analyzed. The genes, p16 and FHIT, are known to be damaged or silenced very early in the process of cancer development.
Study participants gave both an oral and lung sample initially and then another at three months. The researchers tracked whether either p16, FHIT or both had been silenced. Their baseline tissue comparison showed the percentages of the silenced or damaged genes were similar in mouth and oral tissue.
"Our study provides the first systematic evidence that accessible tissue, the oral epithelium, can be used to monitor molecular events in less accessible tissue," Bhutani said. "This provides a convenient biomonitoring method to provide insight into the molecular events that take place in the lungs of chronic smokers."
One follow-up area of study is to find additional biomarkers in oral tissue. Their study opens the door to enhancing the ability to predict who has higher probability of getting tobacco-related cancers, "not only lung cancer, but pancreatic, bladder and head-and-neck cancers, which also are associated with tobacco use," said the research team.
(Agencies via Xinhua News Agency April 14, 2008)