Investigation of BK virus, Epstein-Barr virus and human papillomavirus sequences in postoperative thyroid gland specimens. Int J Biol Markers. 2015;30:e104-e110. [PMID: 25262702 DOI: 10.5301/jbm.5000115]

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.

The Potential Role of Virus Infection in the Progression of Thyroid Cancer

Multiple factors have engaged in the progression of thyroid cancer (TC). Recent studies have shown that viral infection can be a critical factor in the pathogenesis of TC. Viruses, such as Epstein-Barr virus (EBV), hepatitis C virus (HCV), human immunodeficiency virus (HIV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), may play an essential role in the occurrence, development, and even prognosis in TC. This review mainly explored the potential role of viral infection in the progress of TC. The possible mechanisms could be recognizing the host cell, binding to the receptors, affecting oncogenes levels, releasing viral products to shape a beneficial environment, interacting with immune cells to induce immune evasion, and altering the pituitary-thyroid axis. Thus, comprehensive knowledge may provide insights into finding molecular targets for diagnosing and treating virus-related TC.

Association of thyroid cancer with human papillomavirus infections

While Human Papillomavirus (HPV) particles have been detected in a small proportion of benign thyroid nodules or thyroid cancer cases, a role of HPV in these thyroid conditions has not been established. This study aims to investigate the association of HPV infection with thyroid cancer (TC) using a nationwide population-based study. We retrieved data for this case-control study from Taiwan's Longitudinal Health Insurance Database 2010. The study sample included 3062 patients with TC and 9186 propensity-scored matched controls. We employed multivariate logistic regression models to quantitatively evaluate the association of TC with HPV infections after taking age, sex, monthly income, geographic location and urbanization level of the patient's residence, diabetes, hypertension, and hyperlipidemia into considerations. Chi-squared test revealed that there was a significant difference in the prevalence of prior HPV infections between patients with TC and controls (15.3% vs. 7.6%, p < 0.001). The adjusted odds ratio of prior HPV infections for patients with TC was 2.199 (95% CI = 1.939-2.492) relative to controls. The adjusted ORs of prior HPV infections for patients with TC was similar for males and females. Our research suggests a significant link between HPV infection and the development of TC.

BK polyomavirus in Iranian patients with papillary thyroid cancer: Is it a major future challenge?

BK polyomavirus (BKPyV) is a well-known cause of nephropathy in renal transplant recipients. It has recently received much attention from researchers as a major predisposing factor for various cancers. This study aimed to investigate how BKPyV affected the advancement of papillary thyroid carcinoma (PTC). A total of 1057 samples were tested for BKPyV DNA and RNA, comprising 645 paraffin-embedded PTC biopsy samples (PEBS), 412 fresh biopsy samples (FBS), and 1057 adjacent noncancerous samples. The BKPyV DNA was found in 511 (48.3%) of the specimens, including 347 (84.2%) FBS and 164 (25.4%) PEBS. The mean BKPyV copy number was significantly lower in patients with PEBS (0.5 × 10-4  ± 0.1 × 10-4  copies/cell) than in FBS (1.3 × 10-1  ± 0.2 × 10-1  copies/cell) and non-PTC normal samples (0.3 × 10-5  ± 0.04 × 10-5  copies/cell). The PEBS had lower LT-Ag RNA expression than FBS, and no VP1 gene transcript expression was detected. In conclusion, although our findings indicated the presence of BKPyV in some Iranian PTC patients, more research is needed to corroborate these findings.

Traces of JC polyomavirus in papillary thyroid cancer: a comprehensive study in Iran

BACKGROUND

JC polyomavirus (JCPyV) is known to induce solid tumors such as astrocytomas, glioblastomas, and neuroblastomas in experimental animals, and recent studies have shown that the virus may be correlated with carcinogenesis. This study aimed to evaluate the impact of JCPyV on the progression of papillary thyroid cancer (PTC).

METHODS

A total of 1057 samples, including 645 paraffin-embedded PTC biopsy samples (PEBS) and 412 fresh biopsy samples (FBS), and 1057 adjacent non-cancerous samples were evaluated for the presence of JCPyV DNA and RNA.

RESULTS

We observed that 10.8% (114/1057) samples, including 17.5% (72/412) FBS and 6.5% (42/645) PEBS were positive for the JCPyV DNA. Among the JCPyV-positive samples, the mean JCPyV copy number was lower in patients with PEBS (0.3 × 10-4 ± 0.1 × 10-4 copies/cell) compared to FBS (1.8 × 10-1 ± 0.4 × 10-1 copies/cell) and non-PTC normal samples (0.2 × 10-5 ± 0.01 × 10-5 copies/cell), with a statistically significant difference (P < 0.001). The LT-Ag RNA expression was lower in PEBS than in FBS, while no VP1 gene transcript expression was found.

CONCLUSIONS

Although our results confirmed the presence of JCPyV in some Iranian patients with PTC, more research is needed to verify these results.

Comparative Proteomic Profiling of Ectosomes Derived from Thyroid Carcinoma and Normal Thyroid Cells Uncovers Multiple Proteins with Functional Implications in Cancer

Proteins carried by tumor-derived ectosomes play an important role in cancer progression, and are considered promising diagnostic markers. In the present study, a shotgun nanoLC–MS/MS proteomic approach was applied to profile and compare the protein content of ectosomes released in vitro by normal human thyroid follicular epithelial Nthy-ori 3-1 cells and human anaplastic thyroid carcinoma (TC) 8305C cells. Additionally, the pro-migratory and pro-proliferative effects of Nthy-ori 3-1- and 8305C-derived ectosomes exerted on the recipient cells were assessed in wound closure and Alamar Blue assays. A total of 919 proteins were identified in all replicates of 8305C-derived ectosomes, while Nthy-ori 3-1-derived ectosomes contained a significantly lower number of 420 identified proteins. Qualitative analysis revealed 568 proteins present uniquely in 8305C-derived ectosomes, suggesting their applicability in TC diagnosis and management. In addition, 8305C-derived ectosomes were able to increase the proliferation and motility rates of the recipient cells, likely due to the ectosomal transfer of the identified cancer-promoting molecules. Our description of ectosome protein content and its related functions provides the first insight into the role of ectosomes in TC development and progression. The results also indicate the applicability of some of these ectosomal proteins for further investigation regarding their potential as circulating TC biomarkers.

Evidencing the presence of merkel cell polyomavirus in papillary thyroid cancer

Merkel cell polyomavirus (MCPyV) infects most people asymptomatically, but recent reports indicate that the virus may be related to carcinogenesis. This study aimed to evaluate the impact of MCPyV on the development of papillary thyroid cancer (PTC). Totally, 1057 samples, including 412 fresh biopsy samples (FBS) and 645 paraffin-embedded PTC biopsy samples (PEBS), and 1057 adjacent non-cancerous samples were assessed for the presence of MCPyV DNA and RNA. MCPyV DNA was positive in 215 (20.3%) of samples, including 126 (30.6%) in FBS and 89 (13.8%) in PEBS. In MCPyV-positive samples, the mean MCPyV copy number was higher in the patients with FBS (2.3 × 10-1 ± 0.5 × 10-1 copies/cell) compared to PEBS (0.7 × 10-4 ± 0.1 × 10-4 copies/cell) and adjacent non-PTC normal samples (0.3 × 10-5 ± 0.02 × 10-5 copies/cell), indicating a statistically significant difference (P < 0.001). The LT-Ag RNA expression was higher in FBS compared to PEBS, while VP1 gene transcript was not detected in any samples. Although our findings showed the presence of MCPyV in a subset of PTC Iranian patients, further research is required to confirm these findings.

Molecular Identification of Human Papillomavirus DNA in Thyroid Neoplasms: Association or Serendipity?

Background: Human papillomavirus (HPV) is recognized as the most important cofactor in the etiology of cancers of the cervix, esophagus, larynx, and nasopharynx. Experimental evidence suggests that HPV could have an oncogenic influence on thyroid follicular cells; however, to the best of our knowledge, there is no record of its role in human thyroid gland neoplasms.

Objective: The purpose of this study is to describe the frequency and the types of HPV present in neoplastic thyroid tissue by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

Methods: Over 157 samples were analyzed of paraffin-embedded tissue from malignant and benign thyroid tumors. All the paraffin blocks were selected consecutively from the Pathology Tissue Bank archive of the Western Medical Center. The molecular detection and typing were performed at the Molecular Microbiology Laboratory of the Biomedical Research Center, Mexican Institute of Social Security.

Results: The frequency of HPV findings was 2.5% (four cases). HPV-6 was found in two cases of thyroid hyperplasia (2.5%), and HPV-33 in two cases of papillary cancer (4.6%).

Conclusion: The presence of HPV is not frequent in thyroid neoplasms, at least in the studied population. Due to the low prevalence of this virus in our sample, it is not possible to reach conclusions. Further research is needed.

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.

Viral infections and risk of thyroid cancer: A systematic review and empirical bayesian meta-analysis

OBJECTIVE

The associations between viruses and the cancer have been conducted in several studies while there has been no systematic review and meta-analysis about the association between viral infections and thyroid cancer (TC). Therefore, we investigated the association between viral infection and TC risk.

METHODS

Systematic search was done from 1994 to 2019 in Web of sciences (ISI), PubMed, and Scopus databases. Pooled logarithm of odds ratio (OR) and their corresponding 95 % confidence interval (CI) and pooled prevalence of viral infections were calculated to find the association between the viral infections and TC risk and overall prevalence of the viral infections in TC.

RESULTS

Twenty-three of 852 original articles were selected and included in the study. According to the results of the random effect meta-analysis, the pooled prevalence of viral infections in the TC patients was 37 % (95 % C. I = 22 %-55 %). In addition, there was a significant association between viral infections (log (OR) = 1.51, 95 % credible interval = 0.68-2.39) and TC risk. The highest associations were observed between TC risk and Simian Vacuolating Virus 40 (SV40) and B19 infections, respectively. The lowest non-significant association was found between TC risk and Poliovirus type 1 infection. The significantly heterogeneity was observed between included studies (Q test: p-value<0.001; I² = 73.82 %; τ² = 1.08, 95 % Cr. I = 0.47-1.94).

CONCLUSIONS

Results clearly demonstrated the potential pathogenetic association between viral infections and increased risk of TC.

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.

Investigation on the association between thyroid tumorigeneses and herpesviruses

Herpesviruses have been associated with various human malignancies and with thyroid autoimmunity. Aiming to investigate the presence of these viruses in thyroid nodules, we analyzed serum and thyroid tissue from 183 patients (83 benign and 100 malignant thyroid nodules). We also obtained 104 normal thyroid tissues extracted from the contralateral lobe of these patients. We used ELISA to screen the serology of all patients and a real-time quantitative PCR to analyze thyroid tissue viral load in antibody-positive patients. In addition, the presence of herpesviruses was tested by histological analysis in 20 EBV-positive tissues using the expression of LMP-1 by immunohistochemistry (IHC) and EBER by in situ hybridization (ISH). There was no evidence of HSV-2 or CMV DNA, but we found EBV DNA sequences in 29 (16%) thyroid tissue samples. We also found 7 positive EBV cases out of 104 normal tissues. Viral load was higher in tumors than in their respective normal tissues (p = 0.0002). ISH analysis revealed EBER expression in 11 out of 20 (52%) EBV-positive tissues, mostly in malignant cases (8/11, 73%). The presence of high EBV copy numbers in thyroid tumors and the expression of EBER only in malignant cases suggest an association between EBV and thyroid malignancies. However, we did not find any association between the presence of EBV and/or its viral load and any clinical or pathological tumor feature. Further studies aiming to clarify the mechanisms of EBV infection in thyroid cells are necessary to support a possible role in the development of thyroid cancer.

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.

The role of human parvovirus B19 and hepatitis C virus in the development of thyroid disorders

The presence of viruses in the thyroid has been shown, but whether they are implicated in thyroid diseases or are only spectators is under investigation. The most important candidate viruses for autoimmune thyroid disorders (AITD) are hepatitis C virus (HCV) and human parvovirus B19 (or Erythrovirus B19 or EVB19). Retrospective and prospective case-control studies conducted on pathology slides showed (by PCR, in situ hybridization or immunohistochemistry) EVB19 was present in thyroid tissues of patients with autoimmune thyroiditis (AT), Graves' disease and thyroid cancer. Though AITD can be associated with acute EVB19 infection, it is not clear whether EVB19 could have a pathogenetic role in autoimmune thyroid diseases pathophysiology. Many studies have shown that frequently, patients with HCV chronic infection (CHC) show elevated serum anti-thyroperoxidase (TPOAb) and/or anti-thyroglobulin autoantibodies levels, ultrasonographic signs of chronic AT, and subclinical hypothyroidism. In patients with HCV-associated mixed cryoglobulinemia (MC + HCV), AITD were more prevalent with respect to controls, and also vs HCV patients without cryoglobulinemia. Papillary thyroid cancer was more prevalent in MC + HCV or CHC patients than in controls, especially in patients with AT. Recently it has been shown an elevated incidence of new cases of AT and thyroid dysfunction in MC patients. These results suggest an attentive monitoring of thyroid function and nodules in HCV patients with risk factors (female gender, a borderline high initial thyrotropin, TPOAb positivity, a hypoechoic and small thyroid) for the development of thyroid disorders.

The Epstein-Barr virus EBNA2 protein induces a subset of NOTCH target genes in thyroid cancer cell lines but fails to suppress proliferation

BACKGROUND

Epstein-Barr virus is associated with lymphoid and epithelial malignancies and has been reported to infect thyroid cells. The Epstein-Barr virus protein, EBNA2, regulates viral and cellular promoters by binding to RBP-jκ. Similarly, NOTCH1, a tumor suppressor protein in thyroid epithelial cells, competes with EBNA2 for binding to overlapping sites on RBP-jκ. EBNA2 activates a subset of NOTCH-responsive genes in lymphocytes and myocytes; however, the effect of EBNA2 expression on NOTCH targets in epithelial cells is unknown. Here we have explored whether EBNA2 activates NOTCH1 targets in thyroid cancer lines and examined its effect on cellular proliferation.

METHODS

Two human thyroid cancer lines, follicular FTC-236 and anaplastic HTh7, were transfected with EBNA2, NOTCH1, or control vectors. Notch targets were measured using quantitative reverse transcriptase polymerase chain reaction. Cellular proliferation was measured by MTT analysis.

RESULTS

EBNA2 activated only a subset of NOTCH1 targets. Expression of HES1 and HEY1 were increased 10-fold in FTC-236 and HTh7 cells, respectively, but the majority of NOTCH1 targets examined were not affected. In contrast to NOTCH1, EBNA2 did not suppress proliferation.

CONCLUSION

EBNA2 does not activate most Notch1-responsive genes or suppress proliferation in human thyroid cancer cells. Instead, EBNA2 may compete with NOTCH1 for limiting amounts of RBP-jκ in epithelial cells and inhibit certain aspects of NOTCH1 signaling.

BK nephropathy in the native kidneys of patients with organ transplants: Clinical spectrum of BK infection

Nephropathy secondary to BK virus, a member of the Papoviridae family of viruses, has been recognized for some time as an important cause of allograft dysfunction in renal transplant recipients. In recent times, BK nephropathy (BKN) of the native kidneys has being increasingly recognized as a cause of chronic kidney disease in patients with solid organ transplants, bone marrow transplants and in patients with other clinical entities associated with immunosuppression. In such patients renal dysfunction is often attributed to other factors including nephrotoxicity of medications used to prevent rejection of the transplanted organs. Renal biopsy is required for the diagnosis of BKN. Quantitation of the BK viral load in blood and urine are surrogate diagnostic methods. The treatment of BKN is based on reduction of the immunosuppressive medications. Several compounds have shown antiviral activity, but have not consistently shown to have beneficial effects in BKN. In addition to BKN, BK viral infection can cause severe urinary bladder cystitis, ureteritis and urinary tract obstruction as well as manifestations in other organ systems including the central nervous system, the respiratory system, the gastrointestinal system and the hematopoietic system. BK viral infection has also been implicated in tumorigenesis. The spectrum of clinical manifestations from BK infection and infection from other members of the Papoviridae family is widening. Prevention and treatment of BK infection and infections from other Papovaviruses are subjects of intense research.

Herpes and polyoma family viruses in thyroid cancer

Thyroid cancer is considered the most common malignancy that affects the endocrine system. Generally, thyroid cancer derives from follicular epithelial cells, and thyroid cancer is divided into well-differentiated papillary (80% of cases) and follicular (15% of cases) carcinoma. Follicular thyroid cancer is further divided into the conventional and oncocytic (Hürthle cell) type, poorly differentiated carcinoma and anaplastic carcinoma. Both poorly differentiated and anaplastic carcinoma can arise either de novo, or secondarily from papillary and follicular thyroid cancer. The incidence of thyroid cancer has significantly increased for both males and females of all ages, particularly for females between 55–64 years of age, from 1999 through 2008. The increased rates refer to tumors of all stages, though they were mostly noted in localized disease. Recently, viruses have been implicated in the direct regulation of epithelial-mesenchymal transition (EMT) and the development of metastases. More specifically, Epstein-Barr virus (EBV) proteins may potentially lead to the development of metastasis through the regulation of the metastasis suppressor, Nm23, and the control of Twist expression. The significant enhancement of the metastatic potential, through the induction of angiogenesis and changes to the tumor microenvironment, subsequent to viral infection, has been documented, while EMT also contributes to cancer cell permissiveness to viruses. A number of viruses have been identified to be associated with carcinogenesis, and these include lymphotropic herpesviruses, namely EBV and Kaposi's sarcoma-associated herpesvirus [KSHV, also known as human herpesvirus type 8 (HHV8)]; two hepatitis viruses, hepatitis B virus (HBV) and hepatitis C virus (HCV); human papillomaviruses (HPVs); human T cell lymphoma virus (HTLV); and a new polyomavirus, Merkel cell polyomavirus identified in 2008. In this review, we examined the association between thyroid cancer and two oncogenic virus families, the herpes and polyoma family viruses, and we discuss their potential role as causative agents in thyroid carcinogenesis.