Viral colonization in exhaled breath condensate of lung cancer patients: Possible role of EBV and CMV

Human Cytomegalovirus Oncoprotection across Diverse Populations, Tumor Histologies, and Age Groups: The Relevance for Prospective Vaccinal Therapy

The oncogenicity of the human cytomegalovirus (CMV) is currently being widely debated. Most recently, mounting clinical evidence suggests an anti-cancer effect via CMV-induced T cell-mediated tumor destruction. However, the data were mostly obtained from single-center studies and in vitro experiments. Broad geographic coverage is required to offer a global perspective. Our study examined the correlation between country-specific CMV seroprevalence (across 73 countries) and the age-standardized incidence rate (of 34 invasive tumors). The populations studied were stratified according to decadal age periods as the immunologic effects of CMV seropositivity may depend upon age at initial infection. The International Agency for Research on Cancer of the World Health Organization (IARC WHO) database was used. The multivariate linear regression analysis revealed a worldwide inverse correlation between CMV seroprevalence and the incidences of 62.8% tumors. Notably, this inverse link persists for all cancers combined (Spearman's ρ = -0.732, p < 0.001; β = -0.482, p < 0.001, adjusted R2 = 0.737). An antithetical and significant correlation was also observed in particular age groups for the vast majority of tumors. Our results corroborate the conclusions of previous studies and indicate that this oncopreventive phenomenon holds true on a global scale. It applies to a wide spectrum of cancer histologies, additionally supporting the idea of a common underlying mechanism-CMV-stimulated T cell tumor targeting. Although these results further advance the notion of CMV-based therapies, in-depth investigation of host-virus interactions is still warranted.

Detection technologies of volatile organic compounds in the breath for cancer diagnoses

Although there are new approaches in both cancer treatment and diagnosis, overall mortality is a major concern. New technologies have attempted to look at breath volatile organic compounds (VOCs) detection to diagnose cancer. Gas Chromatography and Mass Spectrometry (GC - MS) have remained the gold standard of VOC analysis for decades, but it has limitations in differentiating VOCs between cancer subtypes. To increase efficacy and accuracy, new methods to analyze these breath VOCs have been introduced, such as Solid Phase Microextraction/Gas Chromatography-Mass Spectrometry (SPME/GC-MS), Selected Ion Flow Tube - Mass Spectrometry (SIFT-MS), Proton Transfer Reaction - Mass Spectrometry (PRT-MS), Ion Mobility Spectrometry (IMS), and Colorimetric Sensors. This article highlights new technologies that have been studied and applied in the detection and quantification of breath VOCs for possible cancer diagnoses.

Association of Epstein-Barr virus (EBV) with lung cancer: meta-analysis

Objective

Epstein-Barr virus (EBV) is a virus that is ubiquitous in humans. To investigate the association between EBV infection and lung cancer risk to reveal whether it is involved in the development and development of lung cancer. Although there has been discussion of EBV and lung cancer in the past. Through this study, we hope to deepen our understanding of the causes of lung cancer and provide new clues and targets for the prevention, early diagnosis and treatment of lung cancer. This study is also beneficial to the development of medical science and public health. First of all, the research results are expected to be incorporated into lung cancer prevention and treatment strategies and policies, so as to provide better treatment decisions for lung cancer patients and improve the survival rate and quality of life of patients. At the same time, communicating the research results to the public can help raise awareness of lung cancer risk factors. By encouraging healthy lifestyles and screening measures, the public can reduce their risk of lung cancer. In addition, this study also provides an important foundation for subsequent academic research and scientific exploration. It provides valuable information and inspiration for in-depth understanding of lung cancer and other related fields. Overall, this study makes an important contribution to both medical science and public health.

Method

By September 26, 2022, an online database was used to conduct a literature search in English. Random effects models were employed to estimate the prevalence of EBV with 95% confidence intervals (CIs). Additionally, the pooled odds ratio (OR) and 95%CI were calculated from case-control studies to determine the association between EBV and lung cancer.

Results

In this study of 886 patients with lung cancer, the overall prevalence of EBV infection was found to be 44.36% (95%CI: 4.08-16.9). Fourteen studies were included in the analysis, all of which used a case-control design and involved comparisons of tumors with adjacent or non-adjacent normal and non-cancerous controls. There was a significant difference in the prevalence of EBV infection in lung cancer tissues between China and other regions, with an odds ratio (OR) of 9.36 (95% confidence interval: 4.00-21.94, P<0.001, I²=73.5%). This suggests that the association between EBV infection and lung cancer cases is stronger in China than in other regions. Additionally, the prevalence of EBV infection varied across different pathological types of lung cancer, with rates of 81.08% for pulmonary lymphoepithelioma-like carcinoma (LELC),this a rare subtype of non-small cell lung cancer (NSCLC).34.78% for non-small cell lung cancer, and 21.17% for small cell lung cancer. The statistical analysis indicated that EBV infection was most significantly associated with cancer risk in LELC, while non-small cell lung cancer was more strongly associated with EBV than small cell lung cancer.

Conclusion

The study found that EBV infection increases the risk of lung cancer by more than four times, and this risk is associated with the pathological type, lymphatic infiltration, and degree of differentiation of the lung cancer, particularly in the rare subtype of pulmonary lymphoepithelioma in non-small cell lung cancer(NSCLC). Additionally, there are racial and regional differences in the correlation between EBV-infected lung cancer, with the Asian population showing greater susceptibility. The study used normal or abnormal tissue adjacent to the tumor as a control, which is considered a more accurate method for determining the relationship between EBV infection and lung cancer.

Infection with human cytomegalovirus, Epstein-Barr virus, and high-risk types 16 and 18 of human papillomavirus in EGFR-mutated lung adenocarcinoma

AIM

To assess the frequency of human cytomegalovirus (HCMV), Epstein-Barr virus (EBV), and high-risk types of human papillomavirus (HPV16 and HPV18) infections in lung adenocarcinoma samples.

METHODS

Lung adenocarcinoma cytological smears and their DNA isolates were obtained from patients hospitalized at the Department for Lung Diseases Jordanovac, Zagreb, in 2016 and 2017. Overall, 67 lung adenocarcinoma samples were examined: 34 with epidermal growth factor receptor gene (EGFR) mutations and 33 without EGFR mutations. The EGFR mutation status and virus presence were assessed with a polymerase chain reaction, and random samples were additionally tested for EBV with Sanger sequencing. HCMV, EBV, HPV16, and HPV18 infections were evaluated in relation to EGFR mutation, smoking status, and sex. A meta-analysis of available data about HPV infection in non-small cell lung cancer was performed.

RESULTS

More frequent HCMV, EBV, HPV16, and HPV18 infections were observed in lung adenocarcinoma samples with EGFR mutations than in samples without these mutations. Coinfection of the investigated viruses was observed only in lung adenocarcinoma samples with mutated EGFR. In the group with EGFR mutations, smoking was significantly associated with HPV16 infection. The meta-analysis showed that non-small cell lung cancer patients with EGFR mutations had a higher odds of HPV infection.

CONCLUSION

HCMV, EBV, and high-risk HPV infections are more frequent in EGFR-mutated lung adenocarcinomas, which indicates a possible viral impact on the etiology of this lung cancer subtype.

Epstein–Barr Virus Infection in Lung Cancer: Insights and Perspectives

Lung cancer (LC) is the leading cause of cancer death worldwide. Tobacco smoke is the most frequent risk factor etiologically associated with LC, although exposures to other environmental factors such as arsenic, radon or asbestos are also involved. Additionally, the involvement of some viral infections such as high-risk human papillomaviruses (HR-HPVs), Merkel cell polyomavirus (MCPyV), Jaagsiekte Sheep Retrovirus (JSRV), John Cunningham Virus (JCV), and Epstein–Barr virus (EBV) has been suggested in LC, though an etiological relationship has not yet been established. EBV is a ubiquitous gamma herpesvirus causing persistent infections and some lymphoid and epithelial tumors. Since EBV is heterogeneously detected in LCs from different parts of the world, in this review we address the epidemiological and experimental evidence of a potential role of EBV. Considering this evidence, we propose mechanisms potentially involved in EBV-associated lung carcinogenesis. Additional studies are warranted to dissect the role of EBV in this very frequent malignancy.

Association of COVID-19 and other viral infections with interstitial lung diseases, pulmonary fibrosis, and pulmonary hypertension: A narrative review

Background

Interstitial lung diseases (ILDs) include a broad range of diffuse parenchymal lung disorders and are characterized by diffuse parenchymal lung abnormalities leading to irreversible fibrosis. ILDs are correlated with the occurrence of pulmonary fibrosis (PF), which generally also results in pulmonary hypertension (PH). Interferons, secreted in larger amounts during viral infections, are an important possible risk factor contributing to this outcome.

Aims

In this narrative review, the role of 10 different viral infections on the generation/development of ILDs and their outcomes are described in detail. The aim of this review is to determine the probable risk that COVID-19 and other viral infections pose in the post-infection development of ILDs, PF, and PH.

Methods

Searches in PubMed (Medline), Google Scholar, Web of Science (ISI, Researcher ID, Publons), ResearchGate, Scopus, and secondary sources yielded 134 studies. After exclusion criteria, 92 studies containing the terms “Coronavirus” (COVID-19), “Interstitial Lung Diseases,” “Pulmonary Fibrosis,” “Pulmonary Hypertension” and “viral infections” were selected for inclusion. Selected articles were read with a focus on the roles of the 10 commonly studied viral infections on generation/intensification of ILDs and classified according to their dominant effect on the respiratory system, with a focus on each infection’s effects on parenchyma of the lungs and generation and/or intensification of ILDs.

Results

This review found that ILDs, PF, and PH can occur after a COVID-19 viral infection. Similar results are also seen in post-infection cases of other viral infections, including Epstein–Barr virus, Cytomegalovirus, Human herpesvirus-8, adenovirus, Hepatitis C, Torque-Teno (Transfusion-Transmitted) Virus, Human Immunodeficiency Virus, Severe Acute Respiratory Syndrome, and Middle East Respiratory Syndrome.

Conclusion

Results of current studies show probable possibility for generation and/or intensification of ILDs in COVID-19 infected patients like other studied viruses. Studies on determination of the actual prevalence of ILD, PF and PH in post-COVID-19 infected patients, follow-up studies on the prevention of ILDs in recovered COVID-19 patients, and meta-analyzed studies on pulmonary outcomes of pandemic corona viruses are strongly recommended as topics for future studies.

Particle sizes of infectious aerosols: implications for infection control

The global pandemic of COVID-19 has been associated with infections and deaths among health-care workers. This Viewpoint of infectious aerosols is intended to inform appropriate infection control measures to protect health-care workers. Studies of cough aerosols and of exhaled breath from patients with various respiratory infections have shown striking similarities in aerosol size distributions, with a predominance of pathogens in small particles (<5 μm). These are immediately respirable, suggesting the need for personal respiratory protection (respirators) for individuals in close proximity to patients with potentially virulent pathogens. There is no evidence that some pathogens are carried only in large droplets. Surgical masks might offer some respiratory protection from inhalation of infectious aerosols, but not as much as respirators. However, surgical masks worn by patients reduce exposures to infectious aerosols to health-care workers and other individuals. The variability of infectious aerosol production, with some so-called super-emitters producing much higher amounts of infectious aerosol than most, might help to explain the epidemiology of super-spreading. Airborne infection control measures are indicated for potentially lethal respiratory pathogens such as severe acute respiratory syndrome coronavirus 2.

Exhaled Breath Condensate: A Non-Invasive Source for Tracking of Genetic and Epigenetic Alterations in Lung Diseases

Lung diseases have been recognized as an extensive cause of morbidity and mortality in the worldwide. The high degree of clinical heterogeneity and nonspecific initial symptoms of lung diseases contribute to a delayed diagnosis. So, the molecular and genomic profiling play a pivotal role in promoting the pulmonary diseases. Exhaled breath condensate (EBC) as a novel and potential method for sampling the respiratory epithelial lining fluid is to assess the inflammatory and oxidative stress biomarkers, drugs and genetic alterations in the pathophysiologic processes of lung diseases. The recent studies on the analysis of EBC from both a genetic and epigenetic point of view were searched from database and reviewed. This review provides an overview of the current findings in the tracking of genomic and epigenetic alterations which are potentially effective in better management of cancer detection. In addition, respiratory microbiota DNA using EBC samples in association with pulmonary disease especially lung cancer were investigated. Various studies have concluded that EBC has a great potential for analysis of nuclear and mitochondrial DNA alterations as well as epigenetic modifications and identification of respiratory microbiome. Next-generation sequencing (NGS) based genomic profiling of EBC samples is recommended as a promising approach to establish personalized based prevention, diagnosis, treatment and post-treatment follow-ups for patients with lung diseases especially lung cancer.

Epidermal Growth Factor in Exhaled Breath Condensate as Diagnostic Method for Non-Small Cell Lung Cancer

OBJECTIVE

Lung cancer is one of the most common malignant tumors in humans. Finding a highly sensitive and specific marker is very important. This study investigated the clinical significance of epidermal growth factor in exhaled breath condensate and serum of patients with non-small cell lung cancer.

METHODS

From October 17, 2013, to June 5, 2017, exhaled breath condensate and blood samples from 155 patients with non-small cell lung cancer, 63 patients with benign pulmonary nodules, and 115 healthy controls were collected using a breath condenser. Each sample was analyzed by enzyme-linked immunosorbent assay.

RESULTS

Epidermal growth factor level in the exhaled breath condensate from the non-small cell lung cancer group (197.86 ± 60.67 pg/mL) was higher than that in the healthy group (124.75 ± 36.09 pg/mL), P < .05. Epidermal growth factor level in the exhaled breath condensate of the smoking group (208.85 ± 40.94 pg/mL) was higher than that of the nonsmoking group (185.52 ± 36.88 pg/mL), P < .05. Epidermal growth factor level in the exhaled breath condensate in phases III and IV of non-small cell lung cancer group (212.17 ± 35.41 pg/mL) was higher than that in phases I and II (173.91 ± 38.08 pg/mL), P < .05. Epidermal growth factor level in the exhaled breath condensate of the death group (241.05 ± 27.19 pg/mL) was higher than that of the survival group (188.75 ± 37.07 pg/mL), P < .05. The epidermal growth factor exhaled breath condensate levels were positively correlated with the serum epidermal growth factor levels with a correlation coefficient of 0.495 (P < .05). The sensitivity and specificity of epidermal growth factor exhaled breath condensate test were 80.0% and 89.6%, respectively.

CONCLUSION

The detection of epidermal growth factor level in exhaled breath condensate exhibits is important in the diagnosis, disease monitoring, and prognosis of non-small cell lung cancer.

Breath analysis for respiratory infections

One of the most logical applications of modern breath analysis techniques is to provide information on respiratory infections. Ongoing work in various types of pulmonary infections has begun to denote candidate breath biomarkers of bacterial, viral, and fungal lung infections. Groundbreaking studies have been performed in naturally occurring cases with humans and with animal models of the disease. This has been coupled with cell culture work to understand the nature of the origins of breath biomarkers generated from the pathogen itself as it proliferates. Much work remains to be done, and the published studies described in this chapter are helping to set a foundation for this research area.

Exhaled breath condensate biomarkers for lung cancer

Lung cancer is the main cause of cancer incidence and mortality worldwide and the identification of clinically useful biomarkers for lung cancer detection at both early and metastatic stage is a pressing medical need. Although many improvements have been made in the treatment and in the early screening of this cancer, most diagnosis are made at a late stage, when a lot of genetic and epigenetic changes have occurred. A promising source of biomarkers reflective of the pathogenesis of lung cancer is exhaled breath condensate (EBC), a biological fluid and a natural matrix of the respiratory tract. Molecules such as DNAs, RNAs, proteins, metabolites and volatile compounds are present in EBC, and their presence/absence or their variation in concentrations can be used as biomarkers. The aims of this review are to briefly describe exhaled breath composition, firstly, and then to document some of the EBC candidate biomarkers for lung cancer by dividing them according to their origin (genome, transcriptome, epigenome, metabolome, proteome and microbiota) in order to demonstrate the potential use of EBC as a helpful tool in cancer diagnostics, molecular profiling, therapy monitoring and screening of high risk individuals.