Epstein-Barr virus microRNAs and lung cancer

Exploring clinical implications and role of non-coding RNAs in lung carcinogenesis

Lung cancer is the utmost familiar category of cancer with greatest fatality rate worldwide and several regulatory mechanisms exercise cellular control on critical oncogenic trails implicated in lung associated carcinogenesis. The non-coding RNAs (ncRNAs) are shown to play a variety of regulatory roles, including stimulating cell proliferation, inhibiting programmed cell death, enhancing cancer cell metastatic ability and acquiring resistance to drugs. Furthermore, ncRNAs exhibit tissue-specific expression as well as great stability in bodily fluids. As a consequence, they are strong contenders for cancer based theragnostics. microRNA (miRNA) alters gene expression primarily by either degrading or interfering with the translation of targeted mRNA and long non-coding RNAs (lncRNAs) can influence gene expression by targeting transcriptional activators or repressors, RNA polymers and even DNA-duplex. lncRNAs are typically found to be dysregulated in lung cancer and hence targeting ncRNAs could be a viable strategy for developing potential therapies as well as for overcoming chemoresistance in lung cancer. The purpose of this review is to elucidate the role of ncRNAs, revisiting the recent studies in lung cancer.

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.

Pathogenic Role of Epstein-Barr Virus in Lung Cancers

Human oncogenic viruses account for at least 12% of total cancer cases worldwide. Epstein–Barr virus (EBV) is the first identified human oncogenic virus and it alone causes ~200,000 cancer cases and ~1.8% of total cancer-related death annually. Over the past 40 years, increasing lines of evidence have supported a causal link between EBV infection and a subgroup of lung cancers (LCs). In this article, we review the current understanding of the EBV-LC association and the etiological role of EBV in lung carcinogenesis. We also discuss the clinical impact of the knowledge gained from previous research, challenges, and future directions in this field. Given the high clinical relevance of EBV-LC association, there is an urgent need for further investigation on this topic.

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.

Non-Coding RNAs in Lung Tumor Initiation and Progression

Lung cancer is one of the deadliest forms of cancer affecting society today. Non-coding RNAs, such as microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), through the transcriptional, post-transcriptional, and epigenetic changes they impose, have been found to be dysregulated to affect lung cancer tumorigenesis and metastasis. This review will briefly summarize hallmarks involved in lung cancer initiation and progression. For initiation, these hallmarks include tumor initiating cells, immortalization, activation of oncogenes and inactivation of tumor suppressors. Hallmarks involved in lung cancer progression include metastasis and drug tolerance and resistance. The targeting of these hallmarks with non-coding RNAs can affect vital metabolic and cell signaling pathways, which as a result can potentially have a role in cancerous and pathological processes. By further understanding non-coding RNAs, researchers can work towards diagnoses and treatments to improve early detection and clinical response.

Detection of Epstein-Barr Virus in 130 Cases of Eyelid Sebaceous Gland Carcinoma Using In Situ Hybridization

Purpose

In this study, we aimed to investigate the presence of Epstein–Barr virus (EBV) in the eyelid sebaceous gland carcinoma (SGC) and its association with the clinicopathologic features.

Methods

One hundred and thirty paraffin-embedded SGC specimens were retrieved from the Clinical Pathology Department of Zhongshan Ophthalmic Center. Epstein–Barr virus-encoded RNA (EBER) was detected with in situ hybridization (ISH) using the Leica BOND system autostainer. The age and gender distributions of all patients were analyzed and compared with earlier reports. Pearson's χ² and Fisher's exact tests were used to determine the association between clinicopathological features such as age, gender, laterality eye, tumor basal dimension, degree of tumor differentiation, and EBER positivity. Likewise, the relationship between the grade and tumor basal dimension in EBER-positive SGC of the eyelid was analyzed.

Results

Thirty-four out of one hundred and thirty (26.2%) eyelid SGC specimens were positively stained for EBER. The age range of highest incidence was 46–75 years, and the female to male ratio was 1 : 0.9. No significant correlation was found between EBER-positivity and age (p = 0.5370), gender (p = 0.4758), and degree of tumor differentiation (p = 0.7787). However, EBV positivity was strongly correlated with the right eye (p = 0.0287), the tumor basal dimension (p = 0.0001). EBV positivity grade presented statistically associated with tumor size (p = 0.0329).

Conclusion

We conclude that ISH is a sensitive method to identify EBV in SGC of the eyelid. A possible causal association of EBV in SGC patients is suggested by high frequency of EBER-ISH positivity and its association with the clinicopathologic features.

Detection of Epstein-Barr Virus Infection in Non-Small Cell Lung Cancer

Previous investigations proposed a link between the Epstein-Barr virus (EBV) and lung cancer (LC), but the results are highly controversial largely due to the insufficient sample size and the inherent limitation of the traditional viral screening methods such as PCR. Unlike PCR, current next-generation sequencing (NGS) utilizes an unbiased method for the global assessment of all exogenous agents within a cancer sample with high sensitivity and specificity. In our current study, we aim to resolve this long-standing controversy by utilizing our unbiased NGS-based informatics approaches in conjunction with traditional molecular methods to investigate the role of EBV in a total of 1127 LC. In situ hybridization analysis of 110 LC and 10 normal lung samples detected EBV transcripts in 3 LC samples. Comprehensive virome analyses of RNA sequencing (RNA-seq) data sets from 1017 LC and 110 paired adjacent normal lung specimens revealed EBV transcripts in three lung squamous cell carcinoma and one lung adenocarcinoma samples. In the sample with the highest EBV coverage, transcripts from the BamHI A region accounted for the majority of EBV reads. Expression of EBNA-1, LMP-1 and LMP-2 was observed. A number of viral circular RNA candidates were also detected. Thus, we for the first time revealed a type II latency-like viral transcriptome in the setting of LC in vivo. The high-level expression of viral BamHI A transcripts in LC suggests a functional role of these transcripts, likely as long non-coding RNA. Analyses of cellular gene expression and stained tissue sections indicated an increased immune cell infiltration in the sample expressing high levels of EBV transcripts compared to samples expressing low EBV transcripts. Increased level of immune checkpoint blockade factors was also detected in the sample with higher levels of EBV transcripts, indicating an induced immune tolerance. Lastly, inhibition of immune pathways and activation of oncogenic pathways were detected in the sample with high EBV transcripts compared to the EBV-low LC indicating the direct regulation of cancer pathways by EBV. Taken together, our data support the notion that EBV likely plays a pathological role in a subset of LC.

Effects of ebv-miR-BART7 on tumorigenicity, metastasis, and TRAIL sensitivity of non-small cell lung cancer

OBJECTIVE

To investigate how the Epstein-Barr virus (EBV) encoded microRNA BART7 (miR-BART7) affects tumorigenicity, metastasis, and TRAIL sensitivity of non-small cell lung cancer (NSCLC).

METHODS

Real time-polymerase chain reaction was performed to detect miR-BART7 expression in NSCLC cell lines. A549 and Calu-1 cells transfected with miR-BART7 inhibitors/mimics were used to do the in-vitro experiments, including 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, Annexin V-fluorescein isothiocyanate/PI, wound-healing, transwell, clonogenic assays, Western blot analysis, and anchorage-independent growth assay. Additionally, mice were used to inject A549 cells infected with miR-BART7 inhibitors to observe the tumorigenicity and metastasis of NSCLC.

RESULTS

TRAIL-resistant NSCLC cell lines (H460R, A549, Calu-1, and H1299) exhibited higher miR-BART7 rather than sensitive H460 and H292 cells. After transfected with miR-BART7 inhibitors, we observed an inhibition in proliferation, migration, invasion, and colony formation, but an enhancement in apoptosis as well as expressions of caspase-3 and caspase-8 in A549 and Calu-1 cells. Besides, TRAIL elevated the migration, invasion, and anchorage-independent growth of A549 cells, which was reversed by silencing DR4 and DR5 (siDRs). However, miR-BART7 inhibitors could reduce migration, invasion, and transformation potential of TRAIL treated A549 cells. Moreover, the expression of transforming growth factor-beta 1 (TGFβ1) could be decreased by miR-BART7 inhibitors with or without TRAIL treatment. Moreover, the tumor growth, epithelial-to-mesenchymal transition, and metastasis was suppressed and tumor-free survival was extended after injection of A549-miR-BART7 inhibitors.

CONCLUSION

Inhibition of miR-BART7 exerted inhibitory effects on cell proliferation, migration, invasion, and colony formation, consequently facilitating cell apoptosis and raising TRAIL sensitivity, providing a new therapeutic target in NSCLC.

Lung cancer in lung transplantation: incidence and outcome

Introduction

Malignancies are one of the causes of mortality after lung transplantation. However, little is known about lung cancer outcome after lung transplantation.

Methods

We performed a retrospective search of the lung transplantation database at our institution to identify patients diagnosed with lung cancer after lung transplantation.

Results

Out of 633 lung transplant patients, lung cancer was detected in 23 of them (3.63%). The most common causes for transplantation were idiopathic pulmonary fibrosis (47.8%) and emphysema (43.4%). A total of 18 patients were diagnosed during follow-up, 12 cases in the native lung (52.2%) and 6 cases in the donor lung (26.1%). The diagnosis was evidenced in the explanted lung in five patients (21.7%). The median of time from transplantation to cancer diagnosis was 39.7 months (24.356.6). Lung cancer was the cause of death in 16 patients. Survival rate at1year from diagnosis of lung cancer was 45.64% (95% CI 0.2431 to 0.6473).

Conclusions

Lung transplant recipients constitute a high-risk group for developing lung cancer. Among our patients, lung cancer was predominantly diagnosed in the native lung and at an advanced stage. The primary tumour was the main cause of death in most of these patients.

Prevalence of human papillomavirus, Epstein-Barr virus, and cytomegalovirus in fine needle aspirates from lung carcinoma: A case-control study with review of literature

BACKGROUND

Oncogenic viruses have recently been allied with lung carcinoma, however, the causal association has not been established till date. The study was conducted to determine the prevalence of high-risk Human papillomavirus (HPV; subtypes 16, 18, 31, 33 and 45), Epstein-Barr virus (EBV) and cytomegalovirus (CMV) in lung carcinoma using polymerase chain reaction (PCR) on fine needle aspirates.

METHODS

Fine needle aspirates of patients with lung carcinoma were included as cases. The control samples included normal lung tissue, collected at the time of medico legal autopsies. DNA was extracted from samples of both cases and controls and analysed by PCR for the presence of HPV, EBV and CMV.

RESULTS

A total of 5/73 (6.8%) cases demonstrated the presence of HPV. Of these, 3 were positive for HPV-16 and one each for HPV-18 and HPV-45. A significant association of HPV with squamous cell carcinoma (SCC) (P = 0.01) was observed. Two cases were positive for EBV; however, the difference was not statistically significant for EBV (P = 0.5) as well as CMV. None of the controls were positive for HPV, EBV or CMV.

CONCLUSION

We conclude that fine needle aspirates can serve as reliable sample for PCR based detection of viruses. A significantly higher prevalence of HPV in lung cancer and a significant association with SCC was observed, thereby, indicating a positive link between HPV and etiopathogenesis of lung carcinoma. Diagn. Cytopathol. 2016;44:987-993. © 2016 Wiley Periodicals, Inc.

Cancer co-occurrence patterns in Parkinson's disease and multiple sclerosis-Do they mirror immune system imbalances?

BACKGROUND

To examine the site-specific cancer mortality among deaths registered with Parkinson's disease (PD) and multiple sclerosis (MS). We focused on the patterns related to the most frequent cancers.

METHODS

We analyzed Swiss mortality data over a 39-year period (1969-2007), using a statistical approach applicable to unique daabases, i.e. when no linkage with morbidity databases or disease registries is possible. It was based on a case-control design with bootstrapping to derive standardized mortality ratios (SMR). The cases were defined by the cancer-PD or cancer-MS co-registrations, whereas the controls were drawn from the remaining records with cancer deaths (matching criteria: sex, age, language region of Switzerland, subperiods 1969-1981, 1982-1994, 1995-2007).

RESULTS

For PD we found lower SMRs in lung and liver cancer and higher SMRs in melanoma/skin cancer, and in cancers of breast and prostate. As for MS, the SMR in lung cancer was lower than expected, whereas SMRs in colorectal, breast and bladder cancer were higher.

CONCLUSIONS

A common pattern of associations can be observed in PD and MS, with a lower risk of lung cancer and higher risk of breast cancer than expected. Thus, PD and MS resemble other conditions with similar (schizophrenia) or reversed patterns (rheumatoid arthritis, immunosuppression after organ transplantation).

Discriminating between Terminal- and Non-Terminal Respiratory Unit-Type Lung Adenocarcinoma Based on MicroRNA Profiles

Lung adenocarcinomas can be classified into terminal respiratory unit (TRU) and non-TRU types. We previously reported that non-TRU-type adenocarcinoma has unique clinical and morphological features as compared to the TRU type. Here we investigated whether micro (mi)RNA expression profiles can be used to distinguish between these two subtypes of lung adenocarcinoma. The expression of 1205 human and 144 human viral miRNAs was analyzed in TRU- and non-TRU-type lung adenocarcinoma samples (n = 4 each) by microarray. Results were validated by quantitative real-time (qRT-)PCR and in situ hybridization. A comparison of miRNA profiles revealed 29 miRNAs that were differentially expressed between TRU- and non-TRU adenocarcinoma types. Specifically, hsa-miR-494 and ebv-miR-BART19 were up regulated by > 5-fold, whereas hsa-miR-551b was down regulated by > 5-fold in the non-TRU relative to the TRU type. The miRNA signature was confirmed by qRT-PCR analysis using an independent set of paired adenocarcinoma (non-TRU-type, n = 21 and TRU-type, n = 12) and normal tissue samples. Non-TRU samples showed increased expression of miR-494 (p = 0.033) and ebv-miR-BART19 (p = 0.001) as compared to TRU-type samples. Both miRNAs were weakly expressed in the TRU type but strongly expressed in the non-TRU type. Neither subtype showed miR-551b expression. TRU- and non-TRU-type adenocarcinomas have distinct miRNA expression profiles, suggesting that tumorigenesis in lung adenocarcinoma occur via different pathways.

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

INTRODUCTION

Today, an increasing interest is being addressed to the viral etiology of lung tumors. As a consequence, research efforts are currently being directed to the identification of the new viruses involved in lung carcinogenesis toward which the screening programs could be directed.

OBJECTIVES

The aim of this study was to investigate the airways colonization by the Epstein-Barr virus (EBV) and Citomegalovirus (CMV) in patients affected by lung cancer using, as a respiratory non-invasive sample, the exhaled breath condensate (EBC).

METHODS

About 70 lung-cancer patients and 40 controls were enrolled. All subjects underwent bronchial brushing and EBC collection. EBV-DNA and CMV-DNA were evaluated in both samples by real-time PCR assay.

RESULTS

They were able to detect EBV and CMV in the EBC. An increase of the EBV positivity in non-small cell lung cancer (NSCLC) patients compared with controls and of the CMV in advanced stages of lung cancer were observed. The association of the positivity of the cytology and the CMV test (in EBC or brushing) slightly increased the sensitivity of malignant diagnosis.

CONCLUSION

EBV and CMV resulted detectable in the EBC. In consideration of the potential involvement of these viruses in lung cancer, which was confirmed in this study, future studies in this direction were supported.

Non-Small Cell Lung Cancer in a Very Young Woman: A Case Report and Critical Review of the Literature

BACKGROUND

Lung cancer in young patients is quite uncommon; clinical presentation and outcome in this population compared to the older group are not yet well defined and data about this setting are mostly single-institutional retrospective analyses.

CASE REPORT

We report here a case of a very young woman with diagnosis of early-stage lung adenocarcinoma harboring EML4-ALK rearrangement; she underwent radical surgery and adjuvant chemotherapy according to the pathologic stage. Potential risk factors for lung cancer in our patient are discussed and clinico-pathologic features and outcomes of lung cancer in the young population compared to the elderly are reviewed through discussing studies with sample sizes larger than 100 patients.

CONCLUSIONS

A wide clinical overview should be performed when lung cancer is diagnosed in a young patient. Large-population studies are required to define the molecular signature and clinical behavior of lung cancer in young patients.

Subpathway Analysis based on Signaling-Pathway Impact Analysis of Signaling Pathway

Pathway analysis is a common approach to gain insight from biological experiments. Signaling-pathway impact analysis (SPIA) is one such method and combines both the classical enrichment analysis and the actual perturbation on a given pathway. Because this method focuses on a single pathway, its resolution generally is not very high because the differentially expressed genes may be enriched in a local region of the pathway. In the present work, to identify cancer-related pathways, we incorporated a recent subpathway analysis method into the SPIA method to form the “sub-SPIA method.” The original subpathway analysis uses the k-clique structure to define a subpathway. However, it is not sufficiently flexible to capture subpathways with complex structure and usually results in many overlapping subpathways. We therefore propose using the minimal-spanning-tree structure to find a subpathway. We apply this approach to colorectal cancer and lung cancer datasets, and our results show that sub-SPIA can identify many significant pathways associated with each specific cancer that other methods miss. Based on the entire pathway network in the Kyoto Encyclopedia of Genes and Genomes, we find that the pathways identified by sub-SPIA not only have the largest average degree, but also are more closely connected than those identified by other methods. This result suggests that the abnormality signal propagating through them might be responsible for the specific cancer or disease.

Tracheal ulcer due to Epstein-Barr virus-positive diffuse large B-cell lymphoma of the elderly

A 74-year-old man was referred to our hospital because of a tracheal stenosis circumscribed with soft tissue density and a left pulmonary nodule. Open biopsy of a right submandibular lymph node revealed diffuse large B-cell lymphoma, and the malignant cells were positive for Epstein-Barr virus gene products. Bronchofiberscopy revealed a tracheal necrotizing ulcer. After chemotherapy, the tracheal ulcer resolved. To our knowledge, this is the first report of a case of Epstein-Barr virus-positive diffuse large B-cell lymphoma of the elderly with a tracheal ulcer.

Tripeptide feG prevents and ameliorates acute pancreatitis-associated acute lung injury in a rodent model

BACKGROUND

The synthetic tripeptide feG (D-Phe-D-Glu-Gly) is a novel pharmacologic agent that decreases neutrophil recruitment, infiltration, and activation in various animal models of inflammatory disease. We aimed to investigate the effect of feG as both a preventive treatment when administered before acute lung injury and as a therapeutic treatment administered following initiation of acute lung injury.

METHODS

Lung injury was assessed following prophylactic or therapeutic intratracheal feG administration in a “two-hit” rodent model of acute pancreatitis plus intratracheal lipopolysaccharide.

RESULTS

Following both prophylactic and therapeutic feG administration, there were significant improvements in arterial blood oxygenation and respiratory mechanics and decreased lung edema, BAL protein concentration, histologic tissue injury scores, BAL cell infiltration, and lung myeloperoxidase activity. Most indices of lung damage were reduced to baseline control values.

CONCLUSIONS

feG reduced leukocyte infiltration, ameliorated the severity of inflammatory damage, and restored lung function when administered either prophylactically or therapeutically in a two-hit rat model of acute pancreatitis plus intratracheal lipopolysaccharide.

Primary lung cancer complicated by malignant lymphoma in two cases of epstein-barr virus infection

Background

Double cancer is defined as the co-existence of two pathologically distinct cancers. Double cancer consisting of a lung adenocarcinoma and a malignant lymphoma has seldom been reported in time synchronous cases or prior to cases of primary lung cancer, except in those after treatment for malignant lymphoma.

Case Presentation

Case 1 was a 71-year-old woman who was treated at our hospital for chronic hepatitis C, nontuberculous mycobacteria infection, and bronchiectasis. She was diagnosed with a stage IV lung adenocarcinoma (cT1bN2M1b) with a synchronous complicating diffuse large B-cell-type lymphoma. Case 2 was a 62-year-old man who had undergone resection of a stage IB lung adenocarcinoma (pT2aN0M0). Thirty months after the surgery, a diffuse large B-cell-type lymphoma was discovered. In both cases, high antiviral capsid antigen IgG antibody titers were observed.

Conclusion

Epstein-Barr virus may be associated with the incidence of multiple cancers given the pathological evidence from our two double cancer cases.