Researchers from the University of Texas MD Anderson Cancer Center found that cancer markers are richly expressed from the gene in the area adjacent to tumors in patients with non-small cell lung cancer (NSCLC). They also discovered a new role of a cancer-promoting gene in the lungs and airways of smokers with lung cancer. The study was published online in the Journal of the National Cancer Institute.
“We believe this study has a “double whammy” application,” said Humam Kadara, Ph.D., assistant professor, Translational Molecular Pathology at MD Anderson and lead author of the study. “These cancer-associated changes that distinguish the airways of smokers with lung cancer and healthy smokers may help us diagnose lung cancer earlier and develop more effective strategies for treatment.”
NSCLC is a major form of lung cancer, accounting for almost 90% of the cases. According to the estimation by the ACS, more than 224,000 men and women are diagnosed with lung cancer each year and more than 159,000 people die of the disease.
In the study, 20 patients with NSCLC in stage I to III — 5 of whom were non-smokers and 15 who were smokers — received various genetic tests to examine their lung tumors, unaffected lung tissues, and normal-appearing tissues in airways located varying distances from the tumors.
Researchers found a common feature among lung cancer patients: 1,661 genes are differently expressed between tumors and airways compared with normal lung tissue. They also found that 422 genes and key cancer-associated signaling pathways were expressed more intensely in airway tissues as being closer to the tumor. In addition, higher levels of LAPT4B which is expressed in liver, lung, breast, ovarian and gastric cancers were detected in airway tissues closer to the tumor. LAPT4B overexpression could lead to resistance to chemotherapy against cancers.
“This is the first time the role of this gene in lung cancer has been studied,” said Kadara. “It was highly over-expressed in adjacent normal cells, indicating the possibility of future detection and treatment strategies.”