Nasal swabs may be a noninvasive alternative for detecting lung cancer in former and current smokers, according to a new study.“Given that bronchial and nasal epithelial gene expression are similarly altered by cigarette smoke exposure, we sought to determine if cancer-associated gene expression might also be detectable in the more readily accessible nasal epithelium,” the researchers wrote.In their study, researchers collected nasal epithelial brushings from 375 participants from the AEGIS-1 clinical trial and 130 participants from the AEGIS-2 clinical trial. The AEGIS studies included current and former smokers undergoing diagnostic evaluation for pulmonary lesions that may be cancerous. Researchers used microarrays for gene expression profiling, and compared both bronchial and nasal epithelium.
Researchers identified 535 genes related to lung cancer in the nasal epithelium of patients diagnosed with lung cancer that were not found in patients with benign lesions after 1 year of follow-up. In addition, comparisons with bronchial gene expression data from AEGIS -1 patients showed statistically significant consistent cancer-associated gene expression alterations between the two airway sites.
In addition, the differentially expressed genes found in the nose were enriched with genes associated with the regulation of apoptosis and immune system. “A nasal lung cancer classifier derived in the AEGIS-1 cohort that combined clinical factors (age, smoking status, time since quit, mass size) and nasal gene expression (30 genes) had statistically significantly higher area under the curve (0.81; 95% confidence interval [CI] = 0.74 to 0.89, P = .01) and sensitivity (0.91; 95% CI = 0.81 to 0.97, P = .03) than a clinical-factor only model in independent samples from the AEGIS-2 cohort,” the researchers wrote. Overall, their results suggest that lung cancer-associated injury in the lungs related to smoking extends to the nasal epithelial cells, indicating that nasal swabs may be a potential alternative for lung biopsies.
AEGIS Study Team. Shared gene expression alterations in nasal and bronchial epithelium for lung cancer detection [published online February 27, 2017]]. J Natl Cancer Inst. doi:https://doi.org/10.1093/jnci/djw327.