Tobacco carcinogen-induced 3p14.2 alterations in exfoliated cells collected from the oral cavity of smokers

Oral cancer is usually diagnosed late in the development of the disease when prognosis is poor. This study explored the feasibility of using Fluorescence in situ hybridization (FISH) analysis of exfoliated cells collected from smokers, non-smokers and oral squamous cell carcinoma (OSCC) patients to identify infrequent, but critical alterations to tissue that might predict cancer risk. We focused on the Fragile Histidine Triad (FHIT) locus located on 3p14.2 as it is commonly altered early in the development of the disease. Five signal patterns observed in the tumor margins were not found in samples from non-smokers; of these patterns, 3 were found in smokers. In addition, 16.5% of smokers showed an elevated number of cells with alterations to the FHlT locus. In conclusion, the data showed that FHlT alterations are present in exfoliated cells of smokers, and specific patterns and frequencies of such alterations could be used in screening smokers to identify early changes associated with cancer risk.