Exhaled HPV infection in lung cancer: role of MA at 3p.

BACKGROUND AND AIMS: Lung cancer has recently been associated with human papilloma virus (HPV) infection. The most important event associated with HPV infection in cancer foresees HPV DNA integration into the host genome. Sites of integration such as the fragile site FRA3B adjacent to the FHIT frequently undergo microsatellite alterations (MAs). In this study we aim to verify the role of MAs at 3p in non-small cell lung cancer (NSCLC) with HPV positivity and eventual correlation with sex, histotype, TNM stage and cigarette smoking. METHODS: We enrolled 26 NSCLC patients previously investigated for the presence of HPV in their airways (11 HPV+ and 15 HPV-). All subjects had allelotyping analysis of DNA from exhaled breath condensate (EBC), blood and bronchial brushing of microsatellite D3S1300 located in the chromosomal region 3p. RESULTS: For the first time we described the presence of MAs at 3p in EBC of NSCLC patients with HPV positivity. MAs in EBC corresponded to those in paired brushing. The number of patients with 3p MAs was higher in the group of NSCLC with HPV positivity than with HPV negativity. No relationship between the presence and type of MAs in EBC-brushing/DNA and sex, histotype or tumor stage was found. CONCLUSION: Our results suggested that MAs at 3p are present in caucasic NSLC HPV+ patients and might be involved in lung carcinogenesis. In consideration of the possible clinical usefulness of the analysis of MAS at 3p in the EBC of HPV+ patients in the non-invasive screening for lung cancer, these results merit further studies.