Absence of Simian virus 40, BK, and JC polyomavirus DNA in squamous cell carcinoma limited to the oral cavity

Polyomaviruses and the risk of oral cancer: a systematic review and meta-analysis

OBJECTIVES

Oral cancer (OC) is the most common malignant tumor of the head and neck (HN) and ranks 16th among the most frequently diagnosed cancers worldwide. A systematic review and meta-analysis aimed to provide an evidence-based analysis of the relationship between polyomaviruses and oral cancer.

METHODS

The global online databases was used to identify relevant studies published between January 2000 and September 2024. The quality of each article was assessed using the Newcastle-Ottawa Scale (NOS) checklist. Data analysis was performed using STATA Ver. 11 software, and the standard error was calculated using the binomial distribution formula. The heterogeneity of the study results was assessed using the I-square and Q index, while publication bias was examined using the Begg's test. In addition, a random effects model was used to determine the risk difference (RD), and a forest plot diagram was used to present the results with 95% confidence intervals. The Trim and Fill test was applied to estimate publication bias, and sensitivity analysis was performed to assess the influence of individual studies on the overall estimate.

RESULTS

Of the nine studies, the relationship between BK virus (BKV) and the Merkel cell polyomavirus (MCV) and oral cancer was investigated. In five primary studies, and by combining the results of these studies, the risk of oral cancer in MCV and BKV-positive individuals was significantly higher than in the negative groups by 13% (RD: 0.13, 95% CI: 0.00, 0.26) and 2% (RD: 0.02, 95% CI: -0.03, 0.07), respectively. In addition, the association between JC virus (JCV) and oral cancer was investigated in six primary studies. By combining the results of these studies, the risk of oral cancer in JCV-positive individuals was 1% higher than that in JCV-negative individuals (RD: 0.01, 95% CI: -0.02, 0.06).

DISCUSSION

This meta-analysis showed that there was a significant association between MCV and oral cancer, and the risk of oral cancer in MCV- positive individuals was 13% higher than that in MCV- negative individuals. More preliminary studies are needed on the association between BKV and JCV and the risk of oral cancer.

Polyomavirus JCPyV infrequently detectable in adenoid cystic carcinoma of the oral cavity and the airways

Our objective was to assess the presence of three polyomaviruses, namely SV40, JCPyV, and BKPyV, and human papillomaviruses (HPV) in adenoid cystic carcinomas (ACC) of the minor salivary glands (MiSG) in the head and neck region. The study comprised 68 MiSG ACC patients operated during 1974–2012 at the Helsinki University Hospital (Helsinki, Finland). Medical records and 68 histological samples were reviewed. Polyomaviruses were detected with quantitative PCR and the DNA-positive samples were further analyzed for the presence of viral tumor T antigen (T-ag) with immunohistochemistry. HPV genotyping was performed with a Multiplex HPV Genotyping Kit. Only JCPyV DNA was found in ACC samples, being present in 7 (10.3%) out of the 68 samples. The viral load of JCPyV was low varying between 1 to 226 copies/μg DNA. The JCPyV-positive samples originated from trachea (two samples), paranasal sinuses (one), and oral cavity (two). Additionally, JCPyV positivity was found in one lung metastasis of a tracheal tumor and one local disease failure of an oral cavity tumor. Three JCPyV DNA-positive samples showed weak nuclear staining for large T-ag. In conclusion, only JCPyV but not SV40, BKPyV, or HPV was found in ACC from the upper and lower airways. JCPyV copy numbers were low which might support its role as a “hit and run agent” in ACC carcinogenesis.

Polyomaviruses detectable in head and neck carcinomas

Polyomaviruses (PyV) independent or jointly with human papillomavirus (HPV), might have a role in head and neck carcinomas (HNSCC). We analyzed the prevalence and viral DNA loads of SV40, JCV and BKV with quantitative PCR (qPCR) and all 13 HPyVs with a novel Multiplex method in 82 HNSCC samples with known HPV status and disease-specific survival (DSS) and 24 HNSCC cell lines. JCV was the most prevalent PyV present in 37% of HNSCC and the most prevalent sites were lip (80%), larynx (67%) and oral cavity (59%). JCV viral load was highest in larynx but variation was wide (152514 mean copies/μg DNA, SD± 304820). BKV was found only in one oral carcinoma with low viral load. SV40 was detected in 60% lip and 20.7% oral carcinomas with low copy numbers (6.6- 23.7 copies/μg DNA). Altogether, 86% of JCV-positive samples were co-infected with HPV (p=0.001), with no impact on DSS. Agreement between qPCR and Multiplex methods was substantial (Cohen's kappa= 0.659). Multiplex method detected additional HPyV in five samples. JCV was found in 9/24 HNSCC cell lines, all deriving from oral cavity. Our data provide evidence that JCV might have a role in HNSCC as independent virus or co-factor of HPV.

Human BK Polyomavirus-The Potential for Head and Neck Malignancy and Disease

Members of the human Polyomaviridae family are ubiquitous and pathogenic among immune-compromised individuals. While only Merkel cell polyomavirus (MCPyV) has conclusively been linked to human cancer, all members of the polyomavirus (PyV) family encode the oncoprotein T antigen and may be potentially carcinogenic. Studies focusing on PyV pathogenesis in humans have become more abundant as the number of PyV family members and the list of associated diseases has expanded. BK polyomavirus (BKPyV) in particular has emerged as a new opportunistic pathogen among HIV positive individuals, carrying harmful implications. Increasing evidence links BKPyV to HIV-associated salivary gland disease (HIVSGD). HIVSGD is associated with elevated risk of lymphoma formation and its prevalence has increased among HIV/AIDS patients. Determining the relationship between BKPyV, disease and tumorigenesis among immunosuppressed individuals is necessary and will allow for expanding effective anti-viral treatment and prevention options in the future.

Clinical relevance of systematic human papillomavirus (HPV) diagnosis in oral squamous cell carcinoma

Head & Neck Cancer (HNC) is one of the most common malignancies worldwide and among oral neoplasias about 90-92% are squamous cell carcinomas (OSCC). Alcohol and tobacco consumption have been recognized as the main risk factors for development of OSCC. However, 10 to 20% of patients suffering from OSCC have no history of use of these substances. Clinico-pathological evidence suggests that we are dealing with virally-induced cancers, and that HPV should not be a relevant candidate. A systematic search of HPV in OSCC has no real relevance in current clinical practice even although it is still relevant in organized research protocols. Further studies are ongoing, with the aim of identifying other infectious agents, including viruses, in OSCC.