JC polyomavirus in the aetiology and pathophysiology of glial tumours

Viral oncogenesis in tumours of the central nervous system: reality or random association? A retrospective study on archived material

Central nervous system (CNS) tumours have devastating effects and are recurrent, with dismal prognosis (gliomas) or life‐threatening by the compression effect (meningiomas). This disease's aetiology remains debatable. Over the last decade, the hypothesis that human viruses may be implicated in these tumours has been proposed. In this study, our aim is to examine the presence of 11 viruses in the most frequent CNS primary tumours. Using polymerase chain reaction (PCR), we assessed the viral presence in archived, paraffin‐embedded tumour tissues from 114 patients with glioma and meningioma and in the brain tissue from 40 controls lacking tumour pathology. We focused on candidate neuro‐oncogenic types (herpesviridae and polyomaviruses) and on human papillomavirus (HPV). HPV presence, for which involvement in these tumours was hardly investigated, was found to be associated with both tumour categories compared with controls (glioma, p = 0.032; meningioma, p = 0.032), whereas the presence of the neuro‐oncogenic viruses was found in a negligible number of both categories, suggesting a lack of association with the tumour presence. Moreover, our study reveals a positive correlation between HPV presence and glioma malignancy, and a negative correlation with meningioma grading. Our results suggest that the presence of HPV seems to be significantly associated with primary tumours of the CNS and its meninges.

Occupational livestock or animal dust exposure and offspring cancer risk in Denmark, 1968-2016

OBJECTIVE

To examine associations with occupational livestock or other animal dust exposure and offspring cancer risk.

METHODS

In this population-based case-control study of Danish children aged < 17 years old, 5078 childhood cancer cases diagnosed 1968-2016 were matched to cancer-free controls by birth year and sex (n = 123,228). Occupational livestock or animal dust exposure was identified using a job-exposure matrix. We employed multivariable conditional logistic regression models to estimate associations with offspring cancer for births 1968-2016 and 1989-2016, with the latter timeframe reflecting a period of presumed higher exposure due to changes in Danish farming practices. Sensitivity analyses considered place of birth (urban areas vs. rural areas and small towns).

RESULTS

For births 1968-2016, paternal exposure from offspring birth to cancer diagnosis was associated with central nervous system tumors (adjusted odds ratio [OR] = 1.30, 95% confidence interval [CI] 1.04-1.63) and germ cell tumors (OR = 1.82, 95% CI 1.05-3.27), while maternal pregnancy exposure was associated with astrocytoma (OR = 1.89, 95% CI 1.00-3.57). For births 1989-2016, paternal exposure from offspring birth to cancer diagnosis was negatively associated with acute lymphoid leukemia (OR = 0.58, 95% CI 0.33-1.00). For births in rural areas only, maternal exposure from offspring birth to cancer diagnosis was positively associated with acute myeloid leukemia (OR = 2.16, 95% CI 1.09-4.29).

CONCLUSIONS

This study suggests that paternal occupational animal exposure is associated with offspring germ cell tumors, and maternal pregnancy exposure with astrocytomas. Our results are mixed with respect to leukemia subtypes.

Human Polyomavirus JCPyV and Its Role in Progressive Multifocal Leukoencephalopathy and Oncogenesis

The human neurotropic virus JCPyV, a member of the Polyomaviridiae family, is the opportunistic infectious agent of Progressive Multifocal Leukoencephalopathy (PML), a fatal disease seen in severe immunosuppressive conditions and, during the last decade, in patients undergoing immunotherapy. JCPyV is a ubiquitous pathogen with up to 85% of the adult population word-wide exhibiting antibodies against it. Early experiments demonstrated that direct inoculation of JCPyV into the brain of different species resulted in the development of brain tumors and other neuroectodermal-derived neoplasias. Later, several reports showed the detection of viral sequences in medulloblastomas and glial tumors, as well as expression of the viral protein T-Antigen. Few oncogenic viruses, however, have caused so much controversy regarding their role in the pathogenesis of brain tumors, but the discovery of new Polyomaviruses that cause Merkel cell carcinomas in humans and brain tumors in racoons, in addition to the role of JCPyV in colon cancer and multiple mechanistic studies have shed much needed light on the role of JCPyV in cancer. The pathways affected by the viral protein T-Antigen include cell cycle regulators, like p53 and pRb, and transcription factors that activate pro-proliferative genes, like c-Myc. In addition, infection with JCPyV causes chromosomal damage and T-Antigen inhibits homologous recombination, and activates anti-apoptotic proteins, such as Survivin. Here we review the different aspects of the biology and physiopathology of JCPyV.

Relationship Among Viremia/Viral Infection, Alloimmunity, and Nutritional Parameters in the First Year After Pediatric Kidney Transplantation

The Immune Development in Pediatric Transplantation (IMPACT) study was conducted to evaluate relationships among alloimmunity, protective immunity, immune development, physical parameters, and clinical outcome in children undergoing kidney transplantation. We prospectively evaluated biopsy-proven acute rejection (BPAR), de novo donor-specific antibody (dnDSA) formation, viremia, viral infection, T cell immunophenotyping, and body mass index (BMI)/weight Z scores in the first year posttransplantation in 106 pediatric kidney transplant recipients. Outcomes were excellent with no deaths and 98% graft survival. Rejection and dnDSAs occurred in 24% and 22%, respectively. Pretransplant cytomegalovirus (CMV) and Epstein-Barr virus (EBV) serologies and subsequent viremia were unrelated to BPAR or dnDSA. Viremia occurred in 73% of children (EBV, 34%; CMV, 23%; BMK viremia, 23%; and JC virus, 21%). Memory lymphocyte phenotype at baseline was not predictive of alloimmune complications. Patients who developed viral infection had lower weight (-2.1) (p = 0.028) and BMI (-1.2) (p = 0.048) Z scores at transplantation. The weight difference persisted to 12 months compared with patients without infection (p = 0.038). These data indicate that there is a high prevalence of viral disease after pediatric kidney transplantation, and underweight status at transplantation appears to be a risk factor for subsequent viral infection. The occurrence of viremia/viral infection is not associated with alloimmune events.

Tracing Males From Different Continents by Genotyping JC Polyomavirus in DNA From Semen Samples

The human JC polyomavirus (JCPyV) is an ubiquitous viral agent infecting approximately 60% of humans. Recently, JCPyV sequences have been detected in semen samples. The aim of this investigation was to test whether semen JCPyV genotyping can be employed to trace the origin continent of males. Semen DNA samples (n = 170) from males of different Continents were investigated by PCR for the polymorphic JCPyV viral capsid protein 1 (VP1) sequences, followed by DNA sequencing. JCPyV sequences were detected with an overall prevalence of 27.6% (47/170). DNA sequencing revealed that European males carried JCPyV types 1A (71.4%), 4 (11.4%), 2B (2.9%), 2D1 (2.9%), and 3A (2.9%). Asians JCPyV type 2D1 (66.7%) and Africans JCPyV types 3A (33.3%) and 1A (33.3%). In 10.6% of males, two different JCPyV genotypes were detected, suggesting that the second JCPyV genotype was acquired in the destination country. This study indicates that the majority of semen samples found to be JCPyV-positive, were infected with the JCPyV genotype found in the geographic area of male origin. Therefore, semen JCPyV genotyping could be employed to trace the origin continent of males. Our findings could be applied to forensic investigations, in case of for instance sexual crimes. Indeed, JCPyV genotyping should enable investigators to make additional detailed profiling of the offender. J. Cell. Physiol. 232: 982-985, 2017. © 2016 Wiley Periodicals, Inc.

Review on the role of the human Polyomavirus JC in the development of tumors

Almost one fifth of human cancers worldwide are associated with infectious agents, either bacteria or viruses, and this makes the possible association between infections and tumors a relevant research issue. We focused our attention on the human Polyomavirus JC (JCPyV), that is a small, naked DNA virus, belonging to the Polyomaviridae family. It is the recognized etiological agent of the Progressive Multifocal Leukoencephalopathy (PML), a fatal demyelinating disease, occurring in immunosuppressed individuals.

JCPyV is able to induce cell transformation in vitro when infecting non-permissive cells, that do not support viral replication and JCPyV inoculation into small animal models and non human primates drives to tumor formation. The molecular mechanisms involved in JCPyV oncogenesis have been extensively studied: the main oncogenic viral protein is the large tumor antigen (T-Ag), that is able to bind, among other cellular factors, both Retinoblastoma protein (pRb) and p53 and to dysregulate the cell cycle, but also the early proteins small tumor antigen (t-Ag) and Agnoprotein appear to cooperate in the process of cell transformation.

Consequently, it is not surprising that JCPyV genomic sequences and protein expression have been detected in Central Nervous System (CNS) tumors and colon cancer and an association between this virus and several brain and non CNS-tumors has been proposed. However, the significances of these findings are under debate because there is still insufficient evidence of a casual association between JCPyV and solid cancer development.

In this paper we summarized and critically analyzed the published literature, in order to describe the current knowledge on the possible role of JCPyV in the development of human tumors.

Detection of Malawi polyomavirus sequences in secondary lymphoid tissues from Italian healthy children: a transient site of infection

Background

The novel Malawi polyomavirus (MWPyV) was initially detected in stool specimens from healthy children and children with gastrointestinal symptoms, mostly diarrhea, indicating that MWPyV might play a role in human gastroenteric diseases. Recently, MWPyV sequences were additionally identified in respiratory secretions from both healthy and acutely ill children suggesting that MWPyV may have a tropism for different human tissues. This study was designed to investigate the possible sites of latency/persistence for MWPyV in a cohort of healthy Italian children.

Methods

Specimens (n° 500) of tonsils, adenoids, blood, urines and feces, from 200 healthy and immunocompetent children (age range: 1–15 years) were tested for the amplification of the MWPyV LT antigen sequence by quantitative real-time PCR. Samples (n° 80) of blood and urines from 40 age-matched children with autoimmune diseases, were screened for comparison. Polyomaviruses JC/BK and Epstein-Barr Virus (EBV) were also tested as markers of infection in all samples using the same molecular technique.

Results

In our series of healthy children, MWPyV was detected only in the lymphoid tissues showing a prevalence of 6 % in tonsils and 1 % in adenoids, although with a low viral load. No JCPyV or BKPyV co-infection was found in MWPyV positive samples, while EBV showed a similar percentage of both in tonsils and adenoids (38 and 37 %).

Conversely, no MWPyV DNA was detected in stool from babies with gastroenteric syndrome. With regards to autoimmune children, neither MWPyV nor BKPyV were detected in blood, while JCPyV viremia was observed in 15 % (6/40) of children treated with Infliximab. Urinary BKPyV shedding was observed in 12.5 % (5/40) while JCPyV in 100 % of the samples.

Conclusions

The detection of MWPyV sequences in tonsils and adenoids of healthy children suggests that secondary lymphoid tissues can harbour MWPyV probably as transient sites of persistence rather than actual sites of latency.