Human Papillomavirus in Non-Small Cell Lung Carcinoma: Assessing Virus Presence in Tumor and Normal Tissues and Its Clinical Relevance.

The significance of the role of human papillomavirus (HPV) in the development of lung cancer remains an open question. The data from the literature do not provide conclusive evidence of HPV being involved in the pathogenesis of lung cancer. The aim of this work was to detect the presence of HPV infections with a high carcinogenic risk in patients with non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: the study involved 274 patients with stage IIA-IIIB non-small cell lung cancer. We analyzed normal and tumor tissues as well as blood from each patient. DNA was extracted from patients' specimens, and HPV detection and genotyping was carried out using commercially available kits by PCR. RESULTS: HPV was detected in 12.7% of the patients (35/274 of all cases). We detected nine different types of human papillomavirus in the patients, namely, types 16, 18, 31, 35, 45, 51, 52, 56, and 59. The HPV-positive samples had a clinically insignificant viral load and were predominantly integrated. The relationship between the presence of HPV and its virological parameters and the clinical and pathological parameters of the patients was established. A metastatic-free survival analysis showed that all patients with HPV in the tumor tissue had a higher 5-year survival rate (94%) compared with the HPV-negative patients (78%). The result was not statistically significant (p = 0.08). CONCLUSIONS: data showing a 12.7% human papillomavirus representation among patients with non-small cell lung cancer were obtained. The presence/absence of a viral component in patients with lung cancer was a clinically significant parameter. HPV types 16, 18, and 56, which are the most oncogenic, were most often detected.

Long interspersed nuclear element-1 methylation status in the circulating DNA from blood of patients with malignant and chronic inflammatory lung diseases.

Along with other malignant diseases, lung cancer arises from the precancerous lung tissue state. Aberrant DNA methylation (hypermethylation of certain genes and hypomethylation of retrotransposons) is known as one of the driving forces of malignant cell transformation. Epigenetic changes were shown to be detectable in DNA, circulating in the blood (cirDNA) of cancer patients, indicating the possibility to use them as cancer markers. The current study is the first to compare the Long interspersed nuclear element-1 (LINE-1) methylation level in the blood from lung cancer patients before treatment versus different control groups as healthy subjects, patients with bronchitis and patients with chronic obstructive pulmonary disease (COPD). The concentration of LINE-1 methylated fragments, region 1 (LINE-1 methylated, LINE-1-met) was estimated by quantitative methyl-specific PCR. The total concentration of the circulating LINE-1 copies was measured by qPCR specific for LINE-1 region 2, which was selected due to its CpG methylation-independent sequence (LINE-1-Ind). Both LINE-1 methylation level and LINE-1 methylation index (LINE-1-met/LINE-1-Ind ratio) was decreased in lung cancer patients compared with the joint control group (healthy subjects + patients with bronchitis + COPD patients) (Mann-Whitney U-test, P = 0.016). We also found that the tendency of LINE-1 methylation index decreases in the cirDNA from lung cancer patients versus COPD patients (Mann-Whitney U-test, P = 0.07). Our data indicate that the quantitative analysis of the LINE-1 methylation level in the cirDNA is valuable for discrimination of lung cancer patients from patients with chronic inflammatory lung diseases.

Non-Invasive Diagnosis of Malignancies Based on the Analysis of Markers in Exhaled Air.

Novel non-invasive methods for the diagnosis of malignancies should be effective for early diagnosis, reproducible, inexpensive, and independent from the human factor. Our aim was to establish the applicability of the non-invasive method, based on the analysis of air exhaled by patients who are at different stages of oropharyngeal, larynx and lung cancer. The diagnostic device includes semiconductor sensors capable of measuring the concentrations of gas components in exhaled air, with the high sensitivity of 1 ppm. The neural network uses signals from these sensors to perform classification and identify cancer patients. Prior to the diagnostic procedure of the non-invasive method, we clarified the extent and stage of the tumor according to current international standards and recommendations for the diagnosis of malignancies. The statistical dataset for neural network training and method validation included samples from 121 patients with the most common tumor localizations (lungs, oropharyngeal region and larynx). The largest number of cases (21 patients) were lung cancer, while the number of patients with oropharyngeal or laryngeal cancer varied from 1 to 9, depending on tumor localization (oropharyngeal, tongue, oral cavity, larynx and mucosa of the lower jaw). In the case of lung cancer, the parameters of the diagnostic device are determined as follows: sensitivity-95.24%, specificity-76.19%. For oropharyngeal cancer and laryngeal cancer, these parameters were 67.74% and 87.1%, respectively. This non-invasive method could lead to relevant medicinal findings and provide an opportunity for clinical utility and patient benefit upon early diagnosis of malignancies.