New Insights into the Impact of Human Papillomavirus on Oral Cancer in Young Patients: Proteomic Approach Reveals a Novel Role for S100A8.

Human papillomavirus (HPV) infection has recently been linked to a subset of cancers affecting the oral cavity. However, the molecular mechanisms underlying HPV-driven oral squamous cell carcinoma (OSCC) onset and progression are poorly understood. METHODS: We performed MS-based proteomics profiling based on HPV status in OSCC in young patients, following biological characterization and cell assays to explore the proteome functional landscape. RESULTS: Thirty-nine proteins are differentially abundant between HPV (+) and HPV (-) OSCC. Among them, COPS3, DYHC1, and S100A8 are unfavorable for tumor recurrence and survival, in contrast to A2M and Serpine1, low levels of which show an association with better DFS. Remarkably, S100A8 is considered an independent prognostic factor for lower survival rates, and at high levels, it alters tumor-associated immune profiling, showing a lower proportion of M1 macrophages and dendritic cells. HPV (+) OSCC also displayed the pathogen-associated patterns receptor that, when activated, triggered the S100A8 and NFκB inflammatory responses. CONCLUSION: HPV (+) OSCC has a peculiar microenvironment pattern distinctive from HPV (-), involving the expression of pathogen-associated pattern receptors, S100A8 overexpression, and NFκB activation and responses, which has important consequences in prognosis and may guide therapeutic decisions.

Surgical and Nonsurgical Treatment Protocols for Peri-implantitis: An Overview of Systematic Reviews.

The goal of this overview was to systematically verify the best available literature on surgical and nonsurgical treatments of peri-implantitis to determine evidence-based treatment protocols for peri-implantitis. Three databases (MEDLINE/PubMed, Web of Science, and Cochrane Library/Evidence) were searched by two independent reviewers, including systematic reviews (SRs) that involved randomized controlled trials (RCTs). The search was limited to articles between January 2014 to January 2021 with an English language restriction. In total, 437 articles were initially found, of which only 34 were selected for full-text reading. Nine SRs were included in this study, enrolling 59 different RCTs. Some studies investigated both surgical and nonsurgical techniques, while others focused on only one approach or the other. In total, six of the studies included nonsurgical techniques, and eight included surgical techniques (ie, augmentative, regenerative, and corrective/resective techniques). Nonsurgical interventions appeared to offer some degree of clinical improvements, especially in bleeding on probing levels, but they were not enough to fully treat peri-implantitis. Whereas surgical techniques seemed to be more effective in improving overall clinical parameters, especially probing depth, bleeding on probing, and to some extent, marginal bone level, no specific surgical technique or material (graft or membrane) had a clear advantage over others. Therefore, resective surgical and implantoplasty techniques demonstrated significant improvements in clinical parameters. Although surgical interventions are more indicated to treat peri-implantitis than nonsurgical procedures, the predictability is still a concern due to titanium particles scattered within the local tissue.

DNA methyltransferase expression is associated with cell proliferation in salivary mucoepidermoid carcinoma.

OBJECTIVES: The present study investigated the correlation between the expression of DNA methyltransferase (DNMT)1, DNMT3A, and DNMT3B and the proliferation of mucoepidermoid carcinomas (MECs) using the molecular markers Ki-67 and cyclin D1. This study also demonstrates the effects of 5-aza-2-deoxycytidine (5AC) on the MEC tumor cell lines in relation to DNMT1 and DNMT3A expression, and cell-cycle arrest. MATERIALS AND METHODS: The immunohistochemistry of DNMT1, DNMT3A, DNMT3B, Ki-67, and cyclin D1 was analyzed in 40 samples of MEC and 15 samples of healthy minor salivary glands. The effects of 5AC on DNMT1 and DNMT3B expression in MEC cell lines were analyzed by Western blot, and the effects of 5AC on the cell cycle were analyzed using flow cytometry. RESULTS: The expression of DNMT1 and DNMT3B was more intense in MECs than in healthy salivary glands. A strong correlation was found between the expression of the DNMTs and the proliferation markers. This correlation was validated In Vitro, where treatment with 5AC reduced the expression of the DNMTs and the percentage of cells at the G2/M phase of the cell cycle. CONCLUSION: The expression of DNMT1, DNMT3A, DNMT3B is correlated significantly with the expression of Ki-67 and cyclin D1. The treatment with 5AC reduces DNMT expression and decreases the percentage of cells at the G2/M phase of the cell cycle, while increasing the cells at the G0/G1 phase.