The association of Torque Teno viral load with CMV and BKV infection in pediatric and adolescent kidney transplant patients.

BACKGROUND: Long-term allograft and patient survival after kidney transplantation (KTX) depends on the balance between over- and under-immunosuppression (IS). High levels of IS predispose to opportunistic infections. Plasma load of Torque Teno Virus (TTV), a non-pathogenic highly prevalent Annellovirus, is associated with its hosts immune status, especially after solid organ transplantation. OBJECTIVES: To investigate the association of plasma TTV load and opportunistic viral infections after pediatric KTX. STUDY DESIGN: This retrospective study includes all pediatric KTX patients followed at the Medical University of Vienna 2014-2020. PCR for Cytomegalovirus (CMV), Epstein-Barr virus (EBV), BK virus (BKV), and TTV was performed every 4-8 weeks at routine follow-up visits. RESULTS: 71 pediatric KTX patients were followed with TTV measurements for a median of 2.7 years. TTV plasma load was associated with CMV DNAemia at the next visit with an OR of 2.37 (95 % CI 1.15-4.87; p = 0.03) after adjustment for time after KTX and recipient age. For a cut-off of 7.68 log10 c/mL TTV a sensitivity of 100 %, a specificity of 61 %, a NPV 100 %, and a PPV of 46 % to detect CMV DNAemia at the next visit was calculated. TTV plasma loads were also associated with BKV DNAuria and BKV DNAemia at the next visit, but not with EBV DNAemia. CONCLUSIONS: This is the first study to analyse associations between TTV plasma loads and opportunistic viral infections in pediatric KTX. We were able to present a TTV cut-off for the prediction of clinically relevant CMV DNAemia that might be useful in clinical care.

The mysterious anelloviruses: investigating its role in human diseases.

Anelloviruses (AVs) that infect the human population are members of the Anelloviridae family. They are widely distributed in human populations worldwide. Torque teno virus (TTV) was the first virus of this family to be identified and is estimated to be found in the serum of 80-90% of the human population. Sometime after the identification of TTV, Torque teno mini virus (TTMV) and Torque teno midi virus (TTMDV) were also identified and classified in this family. Since identifying these viruses, have been detected in various types of biological fluids of the human body, including blood and urine, as well as vital organs such as the liver and kidney. They can be transmitted from person to person through blood transfusions, fecal-oral contact, and possibly sexual intercourse. Recent studies on these newly introduced viruses show that although they are not directly related to human disease, they may be indirectly involved in initiating or exacerbating some human population-related diseases and viral infections. Among these diseases, we can mention various types of cancers, immune system diseases, viral infections, hepatitis, and AIDS. Also, they likely use the microRNAs (miRNAs) they encode to fulfill this cooperative role. Also, in recent years, the role of proliferation and their viral load, especially TTV, has been highlighted to indicate the immune system status of immunocompromised people or people who undergo organ transplants. Here, we review the possible role of these viruses in diseases that target humans and highlight them as important viruses that require further study. This review can provide new insights to researchers.

Obesity is associated with a higher Torque Teno viral load compared to leanness.

Introduction: Obesity affects a rising proportion of the population and is an important risk factor for unfavorable outcomes in viral disease including severe acute respiratory syndrome coronavirus 2- associated diseases. Torque Teno virus (TTV) is a ubiquitous and apathogenic virus which reflects the immune function of its host. The aim of this study was to investigate the association between obesity and TTV load - an indirect marker of compromised viral immune response. Methods: TTV was quantified by TTV R-GENE® PCR in a total of 89 participants of which 30 were lean (BMI <25 kg/m2) and 59 were obese (BMI >30 kg/m2). For 38 subjects, follow-up was available after bariatric surgery. Results: TTV load was higher in individuals with obesity (median 2.39, IQR: 1.69-3.33 vs. 1.88, IQR 1.08-2.43 log10 copies/mL; p = 0.027). Multivariable linear modeling revealed an independent association between TTV load and obesity. TTV was positively correlated with waist-to-hip ratio and inversely with 25OH vitamin D levels. Interleukin 6 and fasting insulin resistance were confounders of the association between TTV and obesity, while age was an effect modifier. TTV load increased by 87% (95% CI 2-243%) in the year following bariatric surgery. Discussion: A higher TTV load in obese individuals may reflect compromised immune function and thus might serve for risk stratification of unfavorable outcomes during infectious disease, including coronavirus disease 2019, in this population. Our data warrant further analysis of TTV-based risk assessment in obese individuals in the context of infectious disease-associated outcomes.

DETECTION OF TORQUE TENO VIRUS ANTIGEN AND ASSOCIATED RISK FACTORS AMONG HEMODIALYSIS PATIENTS.

OBJECTIVE: The aim: To determine the prevalence of TTV in patients undergoing hemodialysis and to evaluate the possible risk factors. PATIENTS AND METHODS: Materials and methods: This study was conducted in 93 patients, attending hemodialysis unit at AL-Imammain AL-Kadhimain Medical City Hospital for a period from November 2020 to March 2021. The demographic and clinical characteristics including age, sex, underling medical condition, hepatitis B and C status and laboratory tests such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline Phosphatase (ALP) and total serum bilirubin (TSB) were obtained from the record of the patients in hemodialysis unit in the hospital. Direct detection of TTV-Ag was done by enzyme linked immunosorbent assay (ELISA). RESULTS: Results: TTV-Ag was detected in 38 out of 93 (40.9%) hemodialysis patients. Demographic, clinical and risk factors i.e. sex, age, history of diabetes, history of hypertension, history of blood transfusion, number of blood transfusion, the hemodialysis duration, history of surgery and liver enzymes levels did not show significant relation (P>0.05). CONCLUSION: Conclusions: This study showed high prevalence of Torque Teno virus in hemodialysis patients, however, TTV did not play a role in liver injury among these patients.

Herpes DNAemia and TTV Viraemia in Intensive Care Unit Critically Ill Patients: A Single-Centre Prospective Longitudinal Study.

Introduction: We analysed blood DNAemia of TTV and four herpesviruses (CMV, EBV, HHV6, and HSV-1) in the REAnimation Low Immune Status Marker (REALISM) cohort of critically ill patients who had presented with either sepsis, burns, severe trauma, or major surgery. The aim was to identify common features related to virus and injury-associated pathologies and specific features linking one or several viruses to a particular pathological context. Methods: Overall and individual viral DNAemia were measured over a month using quantitative PCR assays from the 377 patients in the REALISM cohort. These patients were characterised by clinical outcomes [severity scores, mortality, Intensive Care Unit (ICU)-acquired infection (IAI)] and 48 parameters defining their host response after injury (cell populations, immune functional assays, and biomarkers). Association between viraemic event and clinical outcomes or immune markers was assessed using χ2-test or exact Fisher's test for qualitative variables and Wilcoxon test for continuous variables. Results: The cumulative incidence of viral DNAemia increased from below 4% at ICU admission to 35% for each herpesvirus during the first month. EBV, HSV1, HHV6, and CMV were detected in 18%, 12%, 10%, and 9% of patients, respectively. The incidence of high TTV viraemia (>10,000 copies/ml) increased from 11% to 15% during the same period. Herpesvirus viraemia was associated with severity at admission; CMV and HHV6 viraemia correlated with mortality during the first week and over the month. The presence of individual herpesvirus during the first month was significantly associated (p < 0.001) with the occurrence of IAI, whilst herpesvirus DNAemia coupled with high TTV viraemia during the very first week was associated with IAI. Herpesvirus viraemia was associated with a lasting exacerbated host immune response, with concurrent profound immune suppression and hyper inflammation, and delayed return to immune homeostasis. The percentage of patients presenting with herpesvirus DNAemia was significantly higher in sepsis than in all other groups. Primary infection in the hospital and high IL10 levels might favour EBV and CMV reactivation. Conclusion: In this cohort of ICU patients, phenotypic differences were observed between TTV and herpesviruses DNAemia. The higher prevalence of herpesvirus DNAemia in sepsis hints at further studies that may enable a better in vivo understanding of host determinants of herpesvirus viral reactivation. Furthermore, our data suggest that EBV and TTV may be useful as additional markers to predict clinical deterioration in ICU patients.

Molecular evidence for homologous strains of infectious spleen and kidney necrosis virus (ISKNV) genotype I infecting inland freshwater cultured Asian sea bass (Lates calcarifer) in Thailand.

Infectious spleen and kidney necrosis virus (ISKNV) is a fish-pathogenic virus belonging to the genus Megalocytivirus of the family Iridoviridae. In 2018, disease occurrences (40-50% cumulative mortality) associated with ISKNV infection were reported in grown-out Asian sea bass (Lates calcarifer) cultured in an inland freshwater system in Thailand. Clinical samples were collected from seven distinct farms located in the eastern and central regions of Thailand. The moribund fish showed various abnormal signs, including lethargy, pale gills, darkened body, and skin hemorrhage, while hypertrophied basophilic cells were observed microscopically in gill, liver, and kidney tissue. ISKNV infection was confirmed on six out of seven farms using virus-specific semi-nested PCR. The MCP and ATPase genes showed 100% sequence identity among the virus isolates, and the virus was found to belong to the ISKNV genotype I clade. Koch's postulates were later confirmed by challenge assay, and the mortality of the experimentally infected fish at 21 days post-challenge was 50-90%, depending on the challenge dose. The complete genome of two ISKNV isolates, namely KU1 and KU2, was recovered directly from the infected specimens using a shotgun metagenomics approach. The genome length of ISKNV KU1 and KU2 was 111,487 and 111,610 bp, respectively. In comparison to closely related ISKNV strains, KU1 and KU2 contained nine unique genes, including a caspase-recruitment-domain-containing protein that is potentially involved in inhibition of apoptosis. Collectively, this study indicated that inland cultured Asian sea bass are infected by homologous ISKNV strains. This indicates that ISKNV genotype I should be prioritized for future vaccine research.

Pigeon adenovirus and pigeon torque teno virus associated with acute multifocal hepatic necrosis in pigeons in Queensland, Australia.

In 2018, an outbreak resulting in deaths of 28 breeding pigeons was reported north of Brisbane, Australia. The affected birds had runny nasal discharge and poor body condition. Two birds were submitted to Biosecurity Sciences Laboratory, Brisbane, for investigation. A range of diagnostic tests excluded a number of known pathogens, and no virus was isolated in cell culture. Histopathological examination revealed severe acute multifocal necrosis in the liver with eosinophilic intranuclear inclusions in hepatocytes and Kupffer cells. High-throughput sequencing (HTS) revealed full-length sequences for pigeon adenovirus 1 (PiAd-A) and pigeon torque teno virus (PTTV). This report indicates concomitant PiAd-1and PTTV infections in Australian pigeons.

Estimates of Cancer Mortality Attributable to Carcinogenic Infections in Italy.

Several infectious agents are ascertained causes of cancer, but the burden of cancer mortality attributable to carcinogenic infections in Italy is still unknown. To tackle this issue, we calculated the rate and regional distribution of cancer deaths due to infections sustained by seven pathogens ranked as group 1 carcinogenic agents in humans by the International Agency for Research on Cancer. Population attributable fractions related to these agents were applied to annual statistics of cancer deaths coded according to the 10th International Classification of Diseases. The estimated burden of cancer mortality attributable to carcinogenic infections in Italy during the period 2011-2015 was 8.7% of all cancer deaths registered yearly, on average. Approximately 60% of deaths occurred in men, and almost the whole burden was due to four infectious agents (Helicobacter pylori, hepatitis C virus, high-risk human papillomavirus, and hepatitis B virus). The analysis of regional distribution showed a higher number of infection-related cancer deaths in the northern regions, where the estimates reached 30 (Liguria) and 28 (Friuli Venezia Giulia) deaths per 100,000 inhabitants in 2015. Since one-twelfth of cancer deaths were attributable to these modifiable risk factors, the implementation of appropriate prevention and treatment interventions may help to reduce the impact of these infections on cancer mortality.

Enteric Viruses Associated with Mid-growth Turkey Enteritis.

Since August 2014, the University of Minnesota Veterinary Diagnostic Laboratory has received cases of turkey enteritis that are clinically different from previously described cases of poult enteritis syndrome and light turkey syndrome. The birds develop dark green and extremely foul-smelling diarrhea starting at 8-10 wk of age, which may last up to 15-16 wk of age. The affected turkey flocks show poor uniformity, and feed conversion and market weights are reduced. Multiple-age farms are affected more often than the single-age farms. Morbidity varies from flock to flock and in some cases reaches 100%. At necropsy, undigested feed with increased mucus is observed in the intestines along with prominent mucosal congestion and/or hemorrhage. Microscopically, lymphocytic infiltrates expand the villi in duodenum and jejunum to form lymphoid follicles, which are often accompanied by heterophils. Next generation sequencing (Illumina Miseq) on a pool of feces from affected birds identified genetic sequences of viruses belonging to Astroviridae, Reoviridae, Picornaviridae, Picobirnaviridae, and Adenoviridae. On testing pools of fecal samples from apparently healthy (16 pools) and affected birds (30 pools), there was a higher viral load in the feces of affected birds. Picobirnavirus was detected only in the affected birds; 20 of 30 pools (66.7%) were positive. These results indicate that a high viral load of turkey picobirnavirus alone, or in association with novel picornaviruses, may be a cause of this new type of turkey enteritis.

Metatranscriptomic Analysis of Virus Diversity in Urban Wild Birds with Paretic Disease.

Wild birds are major natural reservoirs and potential dispersers of a variety of infectious diseases. As such, it is important to determine the diversity of viruses they carry and use this information to help understand the potential risks of spillover to humans, domestic animals, and other wildlife. We investigated the potential viral causes of paresis in long-standing, but undiagnosed, disease syndromes in wild Australian birds. RNA from diseased birds was extracted and pooled based on tissue type, host species, and clinical manifestation for metagenomic sequencing. Using a bulk and unbiased metatranscriptomic approach, combined with clinical investigation and histopathology, we identified a number of novel viruses from the families Astroviridae, Adenoviridae, Picornaviridae, Polyomaviridae, Paramyxoviridae, Parvoviridae, and Circoviridae in common urban wild birds, including Australian magpies, magpie larks, pied currawongs, Australian ravens, and rainbow lorikeets. In each case, the presence of the virus was confirmed by reverse transcription (RT)-PCR. These data revealed a number of candidate viral pathogens that may contribute to coronary, skeletal muscle, vascular, and neuropathology in birds of the Corvidae and Artamidae families and neuropathology in members of the Psittaculidae The existence of such a diverse virome in urban avian species highlights the importance and challenges in elucidating the etiology and ecology of wildlife pathogens in urban environments. This information will be increasingly important for managing disease risks and conducting surveillance for potential viral threats to wildlife, livestock, and human health.IMPORTANCE Wildlife naturally harbor a diverse array of infectious microorganisms and can be a source of novel diseases in domestic animals and human populations. Using unbiased RNA sequencing, we identified highly diverse viruses in native birds from Australian urban environments presenting with paresis. This research included the clinical investigation and description of poorly understood recurring syndromes of unknown etiology: clenched claw syndrome and black and white bird disease. As well as identifying a range of potentially disease-causing viral pathogens, this study describes methods that can effectively and efficiently characterize emergent disease syndromes in free-ranging wildlife and promotes further surveillance for specific pathogens of potential conservation and zoonotic concern.

Pathogen Surveillance and Detection of Ranavirus (Frog virus 3) in Translocated Gopher Tortoises (Gopherus polyphemus).

Emerging pathogens may pose additional threats to already vulnerable populations of chelonians, such as gopher tortoises (Gopherus polyphemus). In response to a mortality event on a translocation site in northwest Florida, US during 2013-15, 13 gopher tortoises were necropsied and their tissues were screened for 12 pathogens, including Mycoplasma agassizii, Mycoplasma testudineum, and Frog virus 3-like ranavirus (FV3). The DNA of FV3 was detected via quantitative PCR in the gastrointestinal tract of three tortoises. Subsequently, pathogen surveillance was performed on whole blood and oral-cloacal swab samples of live translocated tortoises from two different enclosures within the site (n=68), rehabilitated tortoises from the site (n=18), and tortoises prior to release on site (n=35) during 2015-17. Mycoplasma spp. were present in all groups and years of live tortoises tested. The DNA of FV3 was detected in 15 individuals both with and without clinical signs of disease in 2016. We recaptured 20 tortoises and captured an additional 20 tortoises in 2017 for surveillance, yet FV3 DNA was no longer detected, even in those that had previously tested positive (n=7). The results of this study contribute to the epidemiology of ranavirus in chelonians and suggests that gopher tortoises could be reservoirs for FV3. We recommend that the status of Ranavirus infection should be included for health screens for gopher tortoises in translocation programs.

CMTV-like ranavirus infection associated with high mortality in captive catfish-like loach, Triplophysa siluorides, in China.

Ranaviruses are important emerging pathogens of ectothermic vertebrates that threaten aquaculture and wildlife worldwide. A mortality event occurred in a cultured population of catfish-like loach (Triplophysa siluorides) in Sichuan Province, China. Gross clinical signs of the affected fish included skin lesions and haemorrhagic ulcers, which are often associated with ranaviruses. Inoculation of liver, kidney and spleen tissue homogenates in epithelioma papulosum cyprini (EPC) cells at 25°C resulted in cytopathic effect within 24 hr. Transmission electron microscopy of infected EPC cells revealed hexagonal viral arrays in the cytoplasm and icosahedral geometry of the virions. Following exposure of T. siluroides to the isolated virus, similar clinical signs were observed and the fish experienced 40% and 90% mortality after 21 days at 103.58 and 107.8 TCID50 /0.1 ml doses, respectively, providing evidence the isolated virus was the main causative agent of the mortality event. Diagnostic PCR of the major capsid protein gene of ranavirus showed that all samples of diseased fish and isolated virus were positive. Phylogenetic analysis revealed that the isolated virus, designated as FYLl40220, was associated with the Common Midwife Toad Virus (CMTV)-like ranavirus clade. To our knowledge, this case represents the first report of CMTV-associated mortality in a fish species. Collectively, these results suggest that the host range of CMTV-like ranaviruses is greater than previously thought, and this clade of ranaviruses could have significant economic and biodiversity impacts.

Human papilloma and other DNA virus infections of the cervix: A population based comparative study among tribal and general population in India.

BACKGROUND: Despite being preventable, cervical cancer remains a major health concern among women. Persistent Human Papillomavirus (HPV) and other viral co-infections may influence cervical dysplasia. We determined and compared the prevalence and risk factors of cervical viral infections among the tribal and general population of southern coastal Karnataka, India. METHODS: A population-based cross-sectional survey was conducted among 1140 and 1100 women from tribal and general population, respectively. Cervical infections with HPV, Epstein-Barr Virus (EBV), Cytomegalovirus (CMV) and Herpes-Simplex Virus (HSV) were examined using polymerase chain reactions (PCR) and DNA sequencing. RESULTS: HPV prevalence was higher among tribal women (40.6%) than general population (14.3%) while the prevalence of EBV (55.1%) and CMV (49.4%) were lower among tribal women than general population (74.3% and 77.5%, respectively). HSV infection was observed in tribal women only (1.8%). Among HR-HPV strains, HPV-18 was predominant among tribal population (28.3%) while, HPV-16 was predominant among the general population (9.1%). Infections were associated with age, educational status, unemployment and personal hygiene of tribal women. Phylogenetic analysis revealed that HPV-16 variants of tribal participants were closely related to non-European sublineages indicating greater risk of HPV persistence and carcinogenesis. CONCLUSION: The study provides a comparative estimate for DNA virus infections of the cervix among women from general as well as tribal population in this region and also reveals a different type-specific pattern of viral infection. Further research is required to delineate the role of specific interactions between multiple virus infections and their role in carcinogenesis.

Incidence of Viremia With DNA Viruses in Oncology Patients With Febrile Neutropenia.

BACKGROUND: Although febrile neutropenia (FN) is one of the most common adverse events produced by chemotherapy, its microbiological etiology is determined for only 15% to 30% of cases. OBJECTIVES: We investigated the rate of viremia with common DNA viruses in patients with FN. STUDY DESIGN: From June 2012 to April 2014, 72 blood samples from 24 patients receiving chemotherapy, who experienced FN episodes, were examined for the presence of herpes viruses and other DNA viruses. We used real-time polymerase chain reaction assays to detect herpes simplex virus type 1 and 2, varicella zoster virus, Epstein-Barr virus, cytomegalovirus, human herpes virus types 6 and 7, BK virus and human parvovirus B19 (B19). RESULTS: Viruses were identified in 14 of 72 samples (19.4%). The detected etiological agents were BK virus (5 episodes), human herpes virus type 6 (4 episodes), B19 (4 episodes), Epstein-Barr virus (2 episodes), and cytomegalovirus (1 episode). CONCLUSIONS: Our results indicate that viral infections are common causes in patients with FN. Therefore, viruses may be responsible for FN in a large proportion of patients in whom a causative microorganism could not be identified, and this viral etiology may explain their poor response to antibiotic therapy.

Torquetenovirus detection in exosomes enriched vesicles circulating in human plasma samples.

BACKGROUND: Torquetenovirus (TTV) belongs to Anelloviridae family, infects nearly all people indefinitely without causing overt disease establishing a fine and successful interaction with the host. Increasing evidence have shown some human viruses exploit extracellular vesicles thereby helping viral persistence in the host. Here, the presence of TTV in extracellular vesicles circulating in human plasma was investigated. METHODS: TTV DNA was quantified in plasma-derived exosomes from 122 samples collected from 97 diseased patients and 25 healthy donors. Exosomes enriched vesicles (EEVs) were extracted from plasma and characterized by Nanoparticle tracking analysis, by western blot for presence of tetraspanin CD63, CD81 and annexin II protein and, finally, by electron microscopy (EM). Presence and quantitation of TTV DNA were assessed with an universal single step real-time TaqMan PCR assay. RESULTS: Preliminary investigation showed that the human plasma extracted extracellular vesicles exhibited a main size of 70 nm, had concentration of 2.5 × 109/ml, and scored positive for tetraspanin CD63, CD81 and annexin II, typical characteristic of the exosomes vesicles. EEVs extracted from pooled plasma with TTV DNA viremia of 9.7 × 104 copies/ml showed to contain 6.3 × 102 TTV copies/ml, corresponding to 0.65% of total viral load. Important, TTV yield changed significantly following freezing/thawing, detergents and DNAse treatment of plasma before EEVs extraction. EEVs purified by sucrose-density gradient centrifugation and analysis of gradient fraction positive for exosomes marker CD63 harbored 102 TTV copies/ml. Moreover, EM evidenced the presence of TTV-like particles in EEVs. Successive investigation of plasma EEVs from 122 subjects (37 HIV-positive, 20 HCV infected, 20 HBV infected, 20 kidney transplant recipients, and 25 healthy) reported TTV DNA detection in 42 (34%) of the viremic samples (37 were from diseased patients and 5 from healthy people) at a mean level of 4.8 × 103 copies/ml. The examination of EEVs selected samples reported the presence of TTV genogroup 1, 3, 4 and 5, with genogroup 3 highly observed. CONCLUSIONS: Collectively, although these observations should be confirmed by further studies, circulation of TTV particles in EEVs opens new avenues and mechanistic insights on the molecular strategies adopted by anelloviruses to persist in the host.

Prevalence of human anelloviruses in Romanian healthy subjects and patients with common pathologies.

BACKGROUND: Human anelloviruses (TTV, TTMDV and TTMV) are at high prevalence all across the globe, having also a controversial disease-inducing potential. This study aimed to estimate the prevalence of anelloviral DNA in the Romanian human population and to investigate the association of infections with common pathologies in Romanian population. METHODS: After informed consent, blood samples were collected from 2000 subjects represented by: clinically healthy individuals (n = 701) and a group of patients with pathologies linked to low grade inflammation or alteration of carbohydrate metabolism (n = 1299). All samples were analysed for the presence of TTV, TTMDV and TTMV DNA by hemi-nested PCR. RESULTS: The prevalence of TTV, TTMDV and TTMV in the studied population was 68.2, 54.4%, respectively 40.1%, lower than the recent reports from other geographic regions. The three viral species were significantly more frequent in the group of patients compared to the healthy subjects and were associated with type 2 diabetes mellitus. The presence of anelloviral DNA was also associated with medical procedures (e.g. haemodialysis/transfusions, surgical procedures) and previous hepatitis A virus infection. Lifestyle choices related to alcohol consumption, smoking, physical activity and living environment were not associated with differences in distribution of the three viruses. CONCLUSION: Further evidence is needed to establish a correlation between infection with human anelloviruses and a pathology or group of pathologies.

Cutaneous squamous cell cancer (cSCC) risk and the human leukocyte antigen (HLA) system.

Cutaneous squamous cell carcinoma (cSCC) is the second most common cancer among Caucasians in the United States, with rising incidence over the past decade. Treatment for non-melanoma skin cancer, including cSCC, in the United States was estimated to cost $4.8 billion in 2014. Thus, an understanding of cSCC pathogenesis could have important public health implications. Immune function impacts cSCC risk, given that cSCC incidence rates are substantially higher in patients with compromised immune systems. We report a systematic review of published associations between cSCC risk and the human leukocyte antigen (HLA) system. This review includes studies that analyze germline class I and class II HLA allelic variation as well as HLA cell-surface protein expression levels associated with cSCC risk. We propose biological mechanisms for these HLA-cSCC associations based on known mechanisms of HLA involvement in other diseases. The review suggests that immunity regulates the development of cSCC and that HLA-cSCC associations differ between immunocompetent and immunosuppressed patients. This difference may reflect the presence of viral co-factors that affect tumorigenesis in immunosuppressed patients. Finally, we highlight limitations in the literature on HLA-cSCC associations, and suggest directions for future research aimed at understanding, preventing and treating cSCC.

Detection and Phylogenetic Analysis of Torque Teno Virus in Salivary and Tumor Biopsy Samples from Head and Neck Carcinoma Patients.

OBJECTIVES: Because torque teno virus (TTV) has been implicated in tumorigenesis as a cocarcinogen, we studied TTV prevalence in saliva and biopsy samples from head and neck cancer (HNCC) patients, patients with premalignant lesions of oral cancer, and controls. We also wished to determine the TTV genotypes in HNCC patients. METHODS: A seminested polymerase chain reaction (PCR) amplifying the N22 region of the TTV genome, as well as direct sequencing of PCR fragments, was used. RESULTS: TTV prevalence was higher in HNCC patients (saliva: 27/71, 38%; tumor biopsy: 22/74, 30%) than in controls (saliva: 8/56, 14%; oral mucosa: 1/19, 5%). TTV prevalence was also high in patients with premalignant lesions of oral carcinoma (saliva: 9/18, 50%; biopsy: 5/21, 24%). By phylogenetic analysis, TTV belonging mostly to genotypes 1 and 2 was found in HNCC patients. In most of the cases, identical TTV strains were present in the biopsy and salivary sample of the same HNCC patient. In addition, the same TTV strain was detected in 2 laryngeal carcinoma biopsies obtained from 2 independent patients. CONCLUSIONS: Our data are compatible with the idea that TTV might act as a cocarcinogen in certain cases of HNCC. Alternatively, HNCC may facilitate either TTV replication or TTV entry into the saliva.

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.