Herpes and polyoma family viruses in thyroid cancer

Demonstration of Epstein-Barr Virus by In Situ Hybridization in Papillary Thyroid Carcinomas Developing on Background of Hashimoto's Thyroiditis

AIM

This study aimed to demonstrate the role of Epstein-Barr Virus (EBV) in papillary thyroid carcinomas (PTC) developing on the background of Hashimoto's thyroiditis (HT).

METHODS

The presence of EBV in tumoral tissue, lymphocytes, and peritumoral normal thyroid tissue was investigated using the in situ hybridization method in paraffin blocks. The subtypes of PTC, tumor diameter, TNM stage, multifocality, invasion of thyroid capsule, perineural invasion, and muscular tissue invasion were identified and compared according to EBV involvement.

RESULTS

Eighty-one patients with HT diagnosis, with 93.8% (n=76) female and 6.2% (n=5) male, were included in the study. Papillary microcarcinoma was the pathological diagnosis in 24.2% (n=15) of the cases. EBV was identified in 58.06% (n=36) of the tumor cells nuclei, 58.06% (n=36) in the tumor cell cytoplasm, 16.12% (n=10) in tumor infiltrative lymphocytes, and 53.2% (n=33) in normal parenchymal follicle epithelial cells (NPFEC). In the T2 stage, the rate of EBV nuclear positivity in patients was significantly higher (p=0.034). The classic variant of papillary carcinoma was accompanied by a significantly higher rate of EBV-negative NPFEC (67.6%, p=0.049). In multifocal tumors, EBV positivity was found to be significantly higher in lymphocytes in the surrounding tissues (58.3%, p=0.034).

CONCLUSION

A significant increase in EBV positivity in the surrounding tissue lymphocytes was observed in multifocal PTC developing on a background of HT. This suggests a possible association between HT and EBV.

Role of stress in the pathogenesis of cancer (Review)

Stress is a state of disrupted homeostasis, triggered by intrinsic or extrinsic factors, the stressors, which are counteracted by various physiological and behavioural adaptive responses. Stress has been linked to cancer development and incidence for decades; however, epidemiological studies and clinical trials have yielded contradictory results. The present review discusses the effects of stress on cancer development and the various underlying mechanisms. Animal studies have revealed a clear link between stress and cancer progression, revealing molecular, cellular and endocrine processes that are implicated in these effects. Thus, stress hormones, their receptor systems and their intracellular molecular pathways mediate the effects of stress on cancer initiation, progression and the development of metastases. The mechanisms linking stress and cancer progression can either be indirect, mediated by changes in the cancer microenvironment or immune system dysregulation, or direct, through the binding of neuroendocrine stress‑related signalling molecules to cancer cell receptors. Stress affects numerous anti‑ and pro‑cancer immune system components, including host resistance to metastasis, tumour retention and/or immune suppression. Chronic psychological stress through the elevation of catecholamine levels may increase cancer cell death resistance. On the whole, stress is linked to cancer development and incidence, with psychological stressors playing a crucial role. Animal studies have revealed a better link than human ones, with stress‑related hormones influencing tumour development, migration, invasion and cell proliferation. Randomized controlled trials are required to further evaluate the long‑term cancer outcomes of stress and its management.

Investigation of Parvovirus B19, Cytomegalovirus, Herpes Simplex Virus Types 1 and 2, Human Papillomavirus Types 16 and 18 in Papillary Thyroid Carcinoma

Background & Objective

Viral infections are associated with the pathogenesis and progression of human malignancies. Several studies have suggested the role of viral infections in papillary thyroid carcinoma (PTC). However, the results are still conflicting, and the potential role of viruses in PTC tumorigenesis remains to be elucidated. In the present study, we aimed to investigate the presence of parvovirus B19, cytomegalovirus (CMV), herpes simplex virus types 1 and 2 (HSV-1/HSV-2), and human papillomavirus (HPV) types 16 and 18 in PTC.

Methods

In this cross-sectional study, paraffin-embedded tissue blocks of 40 patients with PTC were used. Tissue blocks were studied for the presence of the virus genome using real-time polymerase chain reaction (PCR).

Results

Of the 40 patients with PTC, there was 1 positive case of HPV (2.5%), while 6 cases were positive for parvovirus B19. HSV and CMV DNAs were not detected in any cases.

Conclusion

Correlations among HSV, CMV, and PTC are unexpected in our patient population. But parvovirus B19 and, to a lesser extent, HPV DNA genomes were detected in PTC using real-time PCR.

Epstein-Barr virus induces morphological and molecular changes in thyroid neoplastic cells

Although the evolution of differentiated thyroid cancer (DTC) is usually indolent, some tumors grow fast, metastasize, and may be fatal. Viruses have been associated with many human tumors, especially the Epstein-Barr virus (EBV), which shows a high viral load in DTC. In order to evaluate the ability of the virus to cause morphological and molecular changes in neoplastic thyroid cell lines TPC-1, BCPAP, and 8505C, a viral adaptation was performed for the analysis of EBV cytopathic effect (CPE), viral kinetics and gene expression analysis of oncogenes KRAS, NRAS, HRAS, and TP53. Comparison of inoculated cells with non-inoculated control cells showed that all tumor cell lines were permissive to the virus. The virus caused CPE in the TPC-1 and 8505C, but not in BCPAP cells. Viral kinetic was similar in both BCPAP and 8505C with a point of eclipse at 24 h post infection. TPC-1 cell line displayed a decreasing growth curve, with highest viral load right after inoculation, which decreased over time. There was hyperexpression of TP53 and NRAS in BCPAP cell (p = 0.012 and p = 0.0344, respectively). The 8505C cell line presented NRAS hyperexpression (p = 0.0255), but lower TP53 expression (p = 0.0274). We concluded that neoplastic thyroid cell lines are permissive to EBV that the virus presents different viral kinetic patterns in different cell lines and produces a CPE on both well-differentiated and undifferentiated thyroid cell lines. We also demonstrated that EBV interferes in oncogene expression in thyroid neoplastic cell lines, suggesting that these effects could be related to different tumor progression patterns.

Simultaneous Effects of Viral Factors of Human Papilloma Virus and Epstein-Barr Virus on Progression of Breast and Thyroid Cancers: Application of Structural Equation Modeling

This study aimed to assess effects of the sets of EBV and HPV expressed proteins simultaneously on the sets of cellular/inflammatory factors in breast and thyroid cancers using structural equation modeling. In this multi-center case-control study, according to the inclusion and exclusion criteria, 83 breast and 57 thyroid specimens were collected from the eligible patients. In addition, 31 and 18 histopathological evaluated normal breast and thyroid samples were also examined as age-matched healthy controls. In addition, ELISA and Real-time PCR were used to measure the expression level of viral and cellular/inflammatory genes and proteins. Structural equation modeling was used to test the causal associations between the sets of EBV and HPV expressed proteins with inflammatory factors in breast and thyroid cancers development. Breast cancer patients had a higher incidence of HPV-positively and EBV-positively than healthy controls (OR=1.66, 95%CI=0.79-3.47, P-value=0.177), (OR=3.18, 95%CI=1.52-6.63, P-value=0.002), respectively. In addition, thyroid cancer patients had a significantly higher incidence of EBV-positivity than healthy controls (OR=3.72, 95% CI=1.65-8.36, P-value=0.001). After fitting the SEM model, HPV proteins factor has significant direct and total effects on the cellular/inflammatory factors in breast cancer (direct effect: β=0.426, P-value=0.01; total effect: β=0.549, P-value<0.001). However, EBV proteins factor has most significant total effect on the cellular/inflammatory factors in breast cancer (total effect: β=0.804, P-value<0.001) than the cellular/inflammatory factors in thyroid cancer (total effect: β=0.789, P-value<0.001). For the first time, a significant association between EBV and HPV -genes, anoikis resistance and the development of breast and thyroid cancers demonstrated by using SEM, Simultaneously.

Human alpha and beta herpesviruses and cancer: passengers or foes?

Based on seroepidemiological studies, human herpes simplex virus types 1 and 2 (HSV-1, HSV-2) are put in relation with a number of cancer diseases; however, they do not appear to play a direct role, being only considered cofactors. Their ability to transform the cells in vitro could be demonstrated experimentally by removing their high lytic ability by a certain dose of UV radiation or by photoinactivation in the presence of photosensitizers, such as neutral red or methylene blue, or culturing under conditions suppressing their lytic activity. However, recent studies indicate that UV irradiated or photoinactivated HSV-1 and HSV-2, able to transform non-transformed cells, behave differently in transformed cells suppressing their transformed phenotype. Furthermore, both transforming and transformed phenotype suppressing activities are pertaining only to non-syncytial virus strains. There are some proposed mechanisms explaining their transforming activity. According to the "hit and run" mechanism, viral DNA induces only initiation of transformation by interacting with cellular DNA bringing about mutations and epigenetic changes and is no longer involved in other processes of neoplastic progression. According to the "hijacking" mechanism, virus products in infected cells may activate signalling pathways and thus induce uncontrolled proliferation. Such a product is e.g. a product of HSV-2 gene designated ICP10 that encodes an oncoprotein RR1PK that activates the Ras pathway. In two cases of cancer, in the case of serous ovarian carcinoma and in some prostate tumours, virus-encoded microRNAs (miRNAs) were detected as a possible cofactor in tumorigenesis. And, recently described herpes virus-associated growth factors with transforming and transformation repressing activity might be considered important factors playing a role in tumour formation. And finally, there is a number of evidence that HSV-2 may increase the risk of cervical cancer after infection with human papillomaviruses. A similar situation is with human cytomegalovirus; however, here, a novel mechanism named oncomodulation has been proposed. Oncomodulation means that HCMV infects tumour cells and modulates their malignant properties without having a direct effect on cell transformation.

Is Epstein-Barr Virus Infection Associated With Thyroid Tumorigenesis?-A Southern China Cohort Study

Background: Epstein-Barr virus (EBV) is associated with many epithelial malignancies. A few reports on the association between EBV and thyroid tumorigenesis have been investigated. However, the conclusion is highly contradictory. We aimed to explore the role of EBV in thyroid nodule development and its clinical significance in a cohort from southern China.

Method: We conducted a retrospective data abstraction study of patients who underwent thyroidectomy between December 2017 and June 2018. We retrospectively analyzed the clinicopathological parameters and EBV infection status (serological antibodies and in situ hybridization).

Result: The cohort comprised 384 patients with newly diagnosed thyroid diseases, including 261 papillary thyroid carcinomas, 87 nodular goiters, 21 follicular adenomas, 12 follicular thyroid carcinomas, and 3 medullary thyroid carcinomas. Forty-two (10.9%) patients were identified as being serological antibody positive. However, there was no association between the clinicopathological parameters and serological antibody positivity. Additionally, none of the patients showed EBER expression in thyroid normal/cancer cell nuclei in in situ hybridization.

Conclusion: In this study, no correlation between EBV and thyroid diseases was found in a cohort from southern China.

Disease Gene Prediction by Integrating PPI Networks, Clinical RNA-Seq Data and OMIM Data

Disease gene prediction is a challenging task that has a variety of applications such as early diagnosis and drug development. The existing machine learning methods suffer from the imbalanced sample issue because the number of known disease genes (positive samples) is much less than that of unknown genes which are typically considered to be negative samples. In addition, most methods have not utilized clinical data from patients with a specific disease to predict disease genes. In this study, we propose a disease gene prediction algorithm (called dgSeq) by combining protein-protein interaction (PPI) network, clinical RNA-Seq data, and Online Mendelian Inheritance in Man (OMIN) data. Our dgSeq constructs differential networks based on rewiring information calculated from clinical RNA-Seq data. To select balanced sets of non-disease genes (negative samples), a disease-gene network is also constructed from OMIM data. After features are extracted from the PPI networks and differential networks, the logistic regression classifiers are trained. Our dgSeq obtains AUC values of 0.88, 0.83, and 0.80 for identifying breast cancer genes, thyroid cancer genes, and Alzheimer's disease genes, respectively, which indicates its superiority to other three competing methods. Both gene set enrichment analysis and predicted results demonstrate that dgSeq can effectively predict new disease genes.

Epstein-Barr virus and thyroid cancer: The role of viral expressed proteins

BACKGROUND

Thyroid cancer is a common endocrine malignancy whose incidence has increased in recent years. Several internal and external risk factors are involved in the development of this cancer, such as infectious agents. Evidence supporting the role of viral infection as an etiology for the invasiveness of thyroid cancer is increasing. The aim of this study was to determine the presence of the Epstein-Barr virus (EBV) and the association between viral gene products and thyroid tumor development.

METHODS

Fifty-seven thyroid cancer specimens were collected from the same number of patients as well as 18 samples from healthy controls. The presence of the EBV genome and the genotyping was examined by polymerase chain reaction (PCR). Also, an enzyme-linked immunosorbent assay and real-time PCR were used to measure the expression levels of viral and cellular genes.

RESULTS

The EBV DNA was detected in 71.9% of the samples, and it was also found that the presence of the EBV was associated with increasing development of thyroid tumor.

CONCLUSION

Our results demonstrated that EBV infection may play a role in the development of thyroid tumor.

Evaluation of the presence of Epstein-Barr virus (EBV) in Iranian patients with thyroid papillary carcinoma

BACKGROUND AND PURPOSE

Papillary thyroid carcinoma (PTC) is the most common thyroid cancer. EBV is one of the most important viruses related to different types of malignancies. This study investigated the relationship between EBV and papillary thyroid carcinoma.

MATERIAL AND METHODS

In this study the presence of Epstein-Barr Nuclear Antigen 1 (EBNA1) gene in papillary thyroid carcinoma tissues were examined by nested-PCR method. Paraffin-embedded tissues (N=41) blocks of thyroid cancer were used. DNA was extracted from all samples and then samples were evaluated for the presence of EBV gene.

RESULTS

In 41 samples, EBNA1 was detected in 65.8% of patients with papillary thyroid carcinoma which was significantly higher in younger ages.

CONCLUSION

The significant presence of EBV genome in papillary thyroid carcinoma suggests that this virus may play a role in this cancer especially in younger ages. As a result, monitoring of patients with EBV latent infection for PTC can be very important.

Epigenetic Treatment of Persistent Viral Infections

Preclinical Research Approximately 2,500 years ago, Hippocrates used the word herpes as a medical term to describe lesions that appeared to creep or crawl on the skin, advocating heat as a possible treatment. During the last 50 years, pharmaceutical research has made great strides, and therapeutic options have expanded to include small molecule antiviral agents, protease inhibitors, preventive vaccines for a handful of the papillomaviruses, and even cures for hepatitis C virus infections. However, effective treatments for persistent and recurrent viral infections, particularly the highly prevalent herpesviruses, continue to represent a significant unmet medical need, affecting the majority of the world's population. Exploring the population diversity of the human microbiome and the effects its compositional variances have on the immune system, health, and disease are the subjects of intense investigational research and study. Among the collection of viruses, bacteria, fungi, and single-cell eukaryotes that comprise the human microbiome, the virome has been grossly understudied relative to the influence it exerts on human pathophysiology, much as mitochondria have until recently failed to receive the attention they deserve, given their critical biomedical importance. Fortunately, cellular epigenetic machinery offers a wealth of druggable targets for therapeutic intervention in numerous disease indications, including those outlined above. With advances in synthetic biology, engineering our body's commensal microorganisms to seek out and destroy pathogenic species is clearly on the horizon. This is especially the case given recent breakthroughs in genetic manipulation with tools such as the CRISPR/Cas (clustered regularly interspaced short palindromic repeats/CRISPR-associated) gene-editing platforms. Tying these concepts together with our previous work on the microbiome and neurodegenerative and neuropsychiatric diseases, we suggest that, because mammalian cells respond to a viral infection by triggering a cascade of antiviral innate immune responses governed substantially by the cell's mitochondria, small molecule carnitinoids represent a new class of therapeutics with potential widespread utility against many infectious insults. Drug Dev Res 78 : 24-36, 2017.   © 2016 Wiley Periodicals, Inc.