Mitochondrial DNA alteration in obstructive sleep apnea.

BACKGROUND: Obstructive Sleep Apnea (OSAS) is a disease associated with the increase of cardiovascular risk and it is characterized by repeated episodes of Intermittent Hypoxia (IH) which inducing oxidative stress and systemic inflammation. Mitochondria are cell organelles involved in the respiratory that have their own DNA (MtDNA). The aim of this study was to investigate if the increase of oxidative stress in OSAS patients can induce also MtDNA alterations. METHODS: 46 OSAS patients (age 59.27 ± 11.38; BMI 30.84 ± 3.64; AHI 36.63 ± 24.18) were compared with 36 control subjects (age 54.42 ± 6.63; BMI 29.06 ± 4.7; AHI 3.8 ± 1.10). In blood cells Content of MtDNA and nuclear DNA (nDNA) was measured in OSAS patients by Real Time PCR. The ratio between MtDNA/nDNA was then calculated. Presence of oxidative stress was evaluated by levels of Reactive Oxygen Metabolites (ROMs), measured by diacron reactive oxygen metabolite test (d-ROM test). RESULTS: MtDNA/nDNA was higher in patients with OSAS than in the control group (150.94 ± 49.14 vs 128.96 ± 45.8; p = 0.04), the levels of ROMs were also higher in OSAS subjects (329.71 ± 70.17 vs 226 ± 36.76; p = 0.04) and they were positively correlated with MtDNA/nDNA (R = 0.5, p < 0.01). CONCLUSIONS: In OSAS patients there is a Mitochondrial DNA damage induced by the increase of oxidative stress. Intermittent hypoxia seems to be the main mechanism which leads to this process.

Aspergillus spp. colonization in exhaled breath condensate of lung cancer patients from Puglia Region of Italy.

BACKGROUND: Airways of lung cancer patients are often colonized by fungi. Some of these colonizing fungi, under particular conditions, produce cancerogenic mycotoxins. Given the recent interest in the infective origin of lung cancer, with this preliminary study we aim to give our small contribution to this field of research by analysing the fungal microbiome of the exhaled breath condensate of lung cancer patients from Puglia, a region of Italy. METHODS: We enrolled 43 lung cancer patients and 21 healthy subjects that underwent exhaled breath condensate and bronchial brushing collection. The fungal incidence and nature of sample collected were analysed by using a selected media for Aspergillus species. RESULTS: For the first time we were able to analyse the fungal microbioma of the exhaled breath condensate. 27.9% of lung cancer patients showed a presence of Aspergillus niger, or A. ochraceus or Penicillium ssp. while none of the healthy subjects did so. CONCLUSION: The results confirmed the high percentage of fungal colonization of the airways of lung cancer patients from Puglia, suggesting the need to conduct further analyses in this field in order to evaluate the exact pathogenetic role of these fungi in lung cancer as well as to propose efficient, empirical therapy.

The hsp 16 gene of the probiotic Lactobacillus acidophilus is differently regulated by salt, high temperature and acidic stresses, as revealed by reverse transcription quantitative PCR (qRT-PCR) analysis.

Small heat shock proteins (sHsps) are ubiquitous conserved chaperone-like proteins involved in cellular proteins protection under stressful conditions. In this study, a reverse transcription quantitative PCR (RT-qPCR) procedure was developed and used to quantify the transcript level of a small heat shock gene (shs) in the probiotic bacterium Lactobacillus acidophilus NCFM, under stress conditions such as heat (45 °C and 53 °C), bile (0.3% w/v), hyperosmosis (1 M and 2.5 M NaCl), and low pH value (pH 4). The shs gene of L. acidophilus NCFM was induced by salt, high temperature and acidic stress, while repression was observed upon bile stress. Analysis of the 5' noncoding region of the hsp16 gene reveals the presence of an inverted repeat (IR) sequence (TTAGCACTC-N9-GAGTGCTAA) homologue to the controlling IR of chaperone expression (CIRCE) elements found in the upstream regulatory region of Gram-positive heat shock operons, suggesting that the hsp16 gene of L. acidophilus might be transcriptionally controlled by HrcA. In addition, the alignment of several small heat shock proteins identified so far in lactic acid bacteria, reveals that the Hsp16 of L. acidophilus exhibits a strong evolutionary relationship with members of the Lactobacillus acidophilus group.

New panel of microsatellite alterations detectable in the EBC for lung cancer prognosis.

Our research group demonstrated, in a precedent study, the prognostic power of the 3p microsatellites alterations (MAs) detectable in exhaled breath condensate (EBC) in NSCLC patients. The analysis of genetic markers in the EBC might have precious clinical and economic consequences when inserted in diagnostic and follow up programs for lung cancer. The aim of this study was to evaluate the prognostic value of a new panel of MAs in the EBC of patients with NSCLC. We enrolled 45 NSCLC patients during a period of 36 months and the follow-up period was 156 weeks. We analyzed MAs for eight markers in EBC samples: D3S2338, D3S1266, D3S1300, D3S1304, D3S1289, D5S2094, D3S1313, and AFMa305ye1. Our study showed that the presence of more than 2 simultaneous MAs reduces outcome in NSCLC patients. The new panel of eight microsatellites markers proposed in EBC samples could have a potential clinical role in assessing survival in lung cancer patients.

BIM and mTOR expression levels predict outcome to erlotinib in EGFR-mutant non-small-cell lung cancer.

BIM is a proapoptotic protein that initiates apoptosis triggered by EGFR tyrosine kinase inhibitors (TKI). mTOR negatively regulates apoptosis and may influence response to EGFR TKI. We examined mRNA expression of BIM and MTOR in 57 patients with EGFR-mutant NSCLC from the EURTAC trial. Risk of mortality and disease progression was lower in patients with high BIM compared with low/intermediate BIM mRNA levels. Analysis of MTOR further divided patients with high BIM expression into two groups, with those having both high BIM and MTOR experiencing shorter overall and progression-free survival to erlotinib. Validation of our results was performed in an independent cohort of 19 patients with EGFR-mutant NSCLC treated with EGFR TKIs. In EGFR-mutant lung adenocarcinoma cell lines with high BIM expression, concomitant high mTOR expression increased IC50 of gefitinib for cell proliferation. We next sought to analyse the signalling pattern in cell lines with strong activation of mTOR and its substrate P-S6. We showed that mTOR and phosphodiesterase 4D (PDE4D) strongly correlate in resistant EGFR-mutant cancer cell lines. These data suggest that the combination of EGFR TKI with mTOR or PDE4 inhibitors could be adequate therapy for EGFR-mutant NSCLC patients with high pretreatment levels of BIM and mTOR.

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.