Evaluation of HPV and EBV in OSCC and the expression of p53, p16, E-cadherin, COX-2, MYC, and MLH1.

OBJECTIVE: This study aimed to evaluate the presence of human papillomavirus (HPV) and Epstein-Barr virus (EBV) and the expression of p53, p16, E-cadherin, COX-2, MLH1, and MYC in oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: One hundred OSCC specimens were submitted to in situ hybridization for HPV and EBV, and immunohistochemistry for detection of the human proteins. RESULTS: Thirty-one cases showed HPV in tumor tissue. EBV was not detected in any case investigated. The HPV(+) group demonstrated an increase of staining scores for nuclear p16 (p = .047), cytoplasmic MYC (p = .002), while a decrease for nuclear MLH1 (p = .048), suggesting that HPV may upregulate the expression of the first two proteins and down-regulate the latter. CONCLUSION: Our findings reinforce the hypothesis of the HPV-related oral carcinogenesis involving the expression of p16 and MYC, and MLH1 suppression. Exclusively cytoplasmic stainings for p16, MLH1, and MYC were also associated with more advanced tumors. Finally, in view of the lack of studies correlating the HPV or EBV infection to the expression of oncoproteins, more researches assessing a broader panel of markers and employing different approaches are still necessary in order to understand the role of these viruses as well as the molecular mechanisms involved in the development and progression of oral carcinomas.

Association between Epstein-Barr Virus and Oral Carcinoma: A Systematic Review with Meta-Analysis.

The purpose of this meta-analysis is to evaluate the association of Epstein-Barr virus (EBV) with oral squamous cell carcinoma (OSCC). We searched the electronic scientific databases of PubMed and Scopus and included a total of 53 studies that were published from 1990 to 2019. The analysis yielded a 45.37% (95% confidence interval [CI]: 38.90-51.84; p < 0.001) overall pooled prevalence of EBV. Studies that used the applied methods of in situ hybridization, polymerase chain reaction, immunology, or RNA microarray showed the following pooled prevalence: 46.08%, 40.32, 54.97%, and 74.89%, respectively. EBV-infected individuals have a 2.5 higher risk for developing OSCC (odds ratio: 2.57; 95% CI: 1.23% to 5.36%; p < 0.001). The present meta-analysis supports the hypothesis of EBV association with OSCC, pointing to this virus as a risk factor for neoplasia. Our findings also suggest that EBV latent transcripts (latent membrane protein 1, EBV nuclear antigen 1 and 2, and EBV-encoded small RNAs) have an important role in this process. Furthermore, novel advancements could arise from large and standardized studies that are constructed to probe for other latent gene expression, eliminate confounding factors (tobacco, alcohol, and high-risk human papillomavirus infection), and define the relationship between EBV and oral carcinomas.

Nervo laríngeo inferior não-recorrente / Non-recurrent inferior laryngeal nerve

Introdução: A lesão do nervo laríngeo inferior é uma das complicações dos procedimentos cirúrgicos da glândula tireóide. O risco torna-se maior quando o nervo, que normalmente é recorrente, apresenta variação anatômica, constituindo o nervo laríngeo inferior não-recorrente. Essa variação apresenta-se mais comumente à direita (0,2% a 4%) e, de forma mais rara, à esquerda (0,07%) e está associada a alterações anatômicas de artérias subclávias. O diagnóstico pode ser realizado no pré-operatório através de exames de imagem, o que não é rotina nos serviços de cirurgia. Pacientes e método: Relatamos a detecção intra-operatória do nervo laríngeo inferior não recorrente, todos à direita, em cinco pacientes submetidas à tireoidectomia total. O nervo foi identificado e preservado estruturalmente em todas as pacientes, apesar das dificuldades técnicas para sua localização. Resultados: Exames de videolaringoestroboscopia pós-cirúrgicos confirmaram a preservação funcional dos nervos. Conclusão: O cirurgião que realiza procedimentos de cervicotomia (tireoidectomia, em especial) deve estar alerta a respeito da existência dessa rara variação anatômica e da importância da identificação sistemática do nervo laríngeo inferior, de modo a evitar sua lesão acidental.

Introduction: The injury of the inferior laryngeal nerve is a complication of the surgical procedures on the thyroid gland. It occurs with increased frequency when this nerve has an anomalous anatomy and constitutes the non-recurrent inferior laryngeal nerve. This variation, that is associated with anatomic alterations of subclavian arteries, is more frequent at the right side (0.2% to 4%) and occurs less frequently at the left side (0.07%). The diagnosis can be performed preoperatively with image examinations. However, it is not a routine procedure in the surgery services. Patients and methods: We report the intraoperative detection of the non-recurrent inferior laryngeal nerve at the right side in five patients undergoing total thyroidectomy. In despite of the difficulties, the nerve was identified and preserved structurally in all patients. Results: The postoperative direct laringostroboscopy confirmed the functional preservation of the nerves. Conclusion: The surgeons who work with cervicotomy procedures (principally thyroidectomy) must be aware about the existence of this rare anatomic variation and the importance of the systematic identification of the inferior laryngeal nerve in order to avoid its accidental injury.