Immune cells and cytolytic activity within the tumor microenvironment are being intensively studied. Through transcriptome profiling, immune cell enumeration using the xCell tool and cytolytic activity quantification according to granzyme A (GZMA) and perforin (PRF1) mRNA levels, we investigated immunoreactivity in tumor and/or tumor-free tongue tissue samples from 31 patients with squamous cell carcinoma of the oral tongue and 14 healthy individuals (control tongue tissues). We found significantly altered immune cell compositions (p < 0.001) and elevated cytolytic activity (p < 0.001) in tumor compared to tumor-free samples, and altered infiltration of a subset of immune cells (e.g. CD8+ T cells, p < 0.01) as well as increased cytolytic activity (p < 0.001) in tumor-free compared to control samples. Controlling for patient age at diagnosis and tumor stage, Cox regression analysis showed that high cytolytic activity in tumor-free samples associated with improved disease-free survival (hazard ratio= 4.20, 95% CI = 1.09-16.20, p = 0.037). However, the degree of cytolytic activity in tumor samples did not provide prognostic information. Taken together, our results show the presence of cancer-related immune responses in clinically tumor-free tongue in patients with squamous cell carcinoma of the oral tongue. Measuring cytolytic activity in tumor-free tongue samples contralateral to tumor might thus be an effective approach to predict clinical outcome.

• Keywords
• cytolytic activity, oral tongue, prognosis, squamous cell carcinoma,
• MeSH
• Cytotoxicity, Immunologic MeSH
• Squamous Cell Carcinoma of Head and Neck immunology   mortality   MeSH
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Young Adult MeSH
• Tumor Microenvironment immunology   MeSH
• Tongue Neoplasms immunology   mortality   pathology   MeSH
• Disease-Free Survival MeSH
• Prognosis MeSH
• Retrospective Studies MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Young Adult MeSH
• Male MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

BACKGROUND: The incidence of squamous cell carcinoma of the oral tongue (SCCOT) is increasing in people under age 40. There is an urgent need to identify prognostic markers that help identify young SCCOT patients with poor prognosis in order to select these for individualized treatment. MATERIALS AND METHODS: To identify genetic markers that can serve as prognostic markers for young SCCOT patients, we first investigated four young (≤40 years) and five elderly patients (≥50 years) using global RNA sequencing and whole-exome sequencing. Next, we combined our data with data on SCCOT from the cancer genome atlas (TCGA), giving a total of 16 young and 104 elderly, to explore the correlations between genomic variations and clinical outcomes. RESULTS: In agreement with previous studies, we found that SCCOT from young and elderly patients was transcriptomically and also genomically similar with no significant differences regarding cancer driver genes, germline predisposition genes, or the burden of somatic single nucleotide variations (SNVs). However, a disparate copy number variation (CNV) was found in young patients with distinct clinical outcome. Combined with data from TCGA, we found that the overall survival was significantly better in young patients with low-CNV (n = 5) compared to high-CNV (n = 11) burden (P = 0.044). CONCLUSIONS: Copy number variation burden is a useful single prognostic marker for SCCOT from young, but not elderly, patients. CNV burden thus holds promise to form an important contribution when selecting suitable treatment protocols for young patients with SCCOT.

• Keywords
• age, copy number variation, prognosis, squamous cell carcinoma of the oral tongue, whole-exome sequencing,
• MeSH
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Survival Rate MeSH
• Young Adult MeSH
• Biomarkers, Tumor * MeSH
• Tongue Neoplasms diagnosis   genetics   mortality   MeSH
• Prognosis MeSH
• Exome Sequencing MeSH
• Aged MeSH
• Carcinoma, Squamous Cell diagnosis   genetics   mortality   MeSH
• DNA Copy Number Variations * MeSH
• Age Factors MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Young Adult MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Biomarkers, Tumor * MeSH

The oral tongue is the most common site for tumours within the oral cavity. Despite intense research, there has been no improvement in the survival rate for patients with oral tongue squamous cell carcinoma (OTSCC) during the last decades. Differences between oral cancer patients based on ethno-geographical distribution have been reported. The present study used immunohistochemistry to evaluate commonly used markers of cancer cell phenotypes, E-cadherin, β-catenin and cytokeratins 5 and 19, in 120 patients with OTSCC. To evaluate the impact of ethnicity, patients from Sweden and Italy were included. A higher proportion of Swedish patients exhibited high expression of E-cadherin in their tumours (P=0.039), and high levels of E-cadherin in Swedish OTSCC patients that had succumbed to their disease were associated with poor prognosis. These data demonstrated differences in the pathological characteristics of OTSCC between two different European populations. The findings emphasise the need to take ethnicity/geographical location of patients into account when comparing results from different studies of OTSCC.

• Keywords
• E-cadherin, beta catenin, ethnicity, oral tongue, squamous cell carcinoma,
• Publication type
• Journal Article MeSH

Squamous cell carcinoma of the head and neck (SCCHN) comprises a large group of cancers in the oral cavity and nasopharyngeal area that typically arise in older males in association with alcohol/tobacco usage. Within the oral cavity, the mobile tongue is the most common site for tumour development. The incidence of tongue squamous cell carcinoma (TSCC) is increasing in younger people, which has been suggested to associate with a viral aetiology. Two common human oncogenic viruses, human papilloma virus (HPV) and Epstein-Barr virus (EBV) are known causes of certain types of SCCHN, namely the oropharynx and nasopharynx, respectively. EBV infects most adults worldwide through oral transmission and establishes a latent infection, with sporadic productive viral replication and release of virus in the oral cavity throughout life. In view of the prevalence of EBV in the oral cavity and recent data indicating that it infects tongue epithelial cells and establishes latency, we examined 98 cases of primary squamous cell carcinoma of the mobile tongue and 15 cases of tonsillar squamous cell carcinoma for the presence of EBV-encoded RNAs (EBERs), EBV DNA and an EBV-encoded protein, EBNA-1. A commercially available in situ hybridisation kit targeting EBER transcripts (EBER-ISH) showed a positive signal in the cytoplasm and/or nuclei of tumour cells in 43% of TSCCs. However, application of control probes and RNase A digestion using in-house developed EBER-ISH showed identical EBER staining patterns, indicating non-specific signals. PCR analysis of the BamH1 W repeat sequences did not identify EBV genomes in tumour samples. Immunohistochemistry for EBNA-1 was also negative. These data exclude EBV as a potential player in TSCC in both old and young patients and highlight the importance of appropriate controls for EBER-ISH in investigating EBV in human diseases.

• MeSH
• DNA, Viral analysis   metabolism   MeSH
• Adult MeSH
• In Situ Hybridization MeSH
• Immunohistochemistry MeSH
• Middle Aged MeSH
• Humans MeSH
• Young Adult MeSH
• Tongue Neoplasms pathology   virology   MeSH
• Polymerase Chain Reaction MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Carcinoma, Squamous Cell pathology   virology   MeSH
• Tonsillar Neoplasms pathology   virology   MeSH
• Epstein-Barr Virus Nuclear Antigens genetics   metabolism   MeSH
• Herpesvirus 4, Human genetics   isolation & purification   MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Young Adult MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• DNA, Viral MeSH
• EBV-encoded nuclear antigen 1 MeSH Browser
• Epstein-Barr Virus Nuclear Antigens MeSH

Epigenetic modifications are essential regulators of biological processes. Decreased DNA methylation of OAS2 (2'-5'-Oligoadenylate Synthetase 2), encoding an antiviral protein, has been seen in psoriasis. To provide further insight into the epigenetic regulation of OAS2, we performed pyrosequencing to detect OAS2 DNA methylation status at 11 promoter and first exon located CpG sites in psoriasis (n = 12) and two common subtypes of squamous cell carcinoma (SCC) of the head and neck: tongue (n = 12) and tonsillar (n = 11). Compared to corresponding controls, a general hypomethylation was seen in psoriasis. In tongue and tonsillar SCC, hypomethylation was found at only two CpG sites, the same two sites that were least demethylated in psoriasis. Despite differences in the specific residues targeted for methylation/demethylation, OAS2 expression was upregulated in all conditions and correlations between methylation and expression were seen in psoriasis and tongue SCC. Distinctive methylation status at four successively located CpG sites within a genomic area of 63 bp reveals a delicately integrated epigenetic program and indicates that detailed analysis of individual CpGs provides additional information into the mechanisms of epigenetic regulation in specific disease states. Methylation analyses as clinical biomarkers need to be tailored according to disease-specific sites.

• MeSH
• 2',5'-Oligoadenylate Synthetase genetics   metabolism   MeSH
• CpG Islands * MeSH
• Epigenesis, Genetic * MeSH
• Humans MeSH
• DNA Methylation MeSH
• Head and Neck Neoplasms genetics   metabolism   pathology   MeSH
• Tongue Neoplasms genetics   metabolism   pathology   MeSH
• Promoter Regions, Genetic MeSH
• Psoriasis genetics   metabolism   pathology   MeSH
• Retrospective Studies MeSH
• Carcinoma, Squamous Cell genetics   metabolism   pathology   MeSH
• Case-Control Studies MeSH
• Tonsillar Neoplasms genetics   metabolism   pathology   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• 2',5'-Oligoadenylate Synthetase MeSH
• OAS2 protein, human MeSH Browser