Salivary KLK5 and uPA are potential biomarkers for malignant transformation of OLK and OLP

Causal role of immune cells in head and neck squamous cell carcinoma

Chronic inflammation, immune cell infiltration, and metabolic reprogramming play a crucial role in the development of head and neck squamous cell carcinoma (HNSCC). Based on the summary-level data from a genome-wide association study (GWAS), this study used Mendelian randomization (MR) analysis to investigate the causal relationship between immune cell phenotype and HNSCC. Two-step MR was employed to quantify the proportion of the effect of metabolite-mediated immunophenotypes on HNSCC. 16 immune phenotypes exhibited a causal relationship with HNSCC. HLA DR + CD4 + AC (OR: 1.31, 95% CI 1.07-1.59, P < 0.01) and EM CD8br AC cells (OR: 1.36, 95% CI 1.14-1.62, P < 0.01) showed the most significant P values. 13 metabolites have a causal relationship with HNSCC (P < 0.05). The proportion of the effect of Bilirubin degradation product, C16H18N2O5 (3) levels-mediated HLA DR + CD4 + AC on HNSCC was 7.17% (95% CI 1.04%-13.3%), while the proportion of the effect of Glutamine to alanine ratio-mediated EM CD8br AC on HNSCC was 8.88% (95% CI 2.2%-15.6%). Moreover, single-cell RNA-sequencing analysis confirmed that HLA DR + CD4 + AC and EM CD8br AC cells were commonly present in the HNSCC tumor microenvironment (TME). High expression of two immune phenotypes indicated a poorer prognosis. The results of differentially expressed genes (DEGs) analysis and functional enrichment indicated that Interferon-induced protein with tetratricopeptide repeats 1 (IFIT1)/Follicular dendritic cell secreted protein (FDCSP) and Keratin 19 type I (KRT19)/Kallikrein-related peptidase 5 (KLK5) may be responsible genes for two immune phenotypes, respectively. The results of quantitative real-time polymerase chain reaction (qRT-PCR) and survival analysis showed that FDCSP was significantly downregulated in HNSCC and could exert a protective effect. Collectively, our study clarified the causal relationship between immune cells, metabolites, and HNSCC, providing new insight for clinical diagnosis and treatment of HNSCC.

Activation of the Urokinase Plasminogen Activator/Urokinase Plasminogen Activator Receptor System in Periodontitis: A Case-Control Study

INTRODUCTION

The plasminogen activating (PA) system has a multitude of functions such as wound healing, proteolytic activity, collagen degradation and cell growth, and the role of the urokinase plasminogen activator/urokinase plasminogen activator receptor (uPA/uPAR) system has been studied in many disease states. The aim of this study was to investigate salivary concentrations of uPA, uPAR and uPA activity in patients with periodontitis to identify biomarkers and novel pathogenic relationships.

METHODS

Saliva samples were obtained from 169 participants, comprising patients with periodontitis (n = 103) and periodontally healthy volunteers (n = 66) and analysed for uPA and uPAR with a multiplex protein assay using proximity extension analysis in a subset of samples, followed by validation with ELISA. The protease activity of salivary uPA was quantified using a fluorometric assay.

RESULTS

Patients with periodontitis had a 4.0-fold higher (p < 0.001) salivary uPA and a 2.5-fold higher (p < 0.001) salivary uPAR concentration in comparison to periodontally healthy participants. The salivary uPA activity (median [IQR]) from patients with periodontitis (123.21 [188.29] U/mL) was 1.6-fold higher (p < 0.01) than the salivary uPA activity from periodontally healthy participants (76.83 [98.09] U/mL). Levels of uPA and uPAR were strongly correlated with periodontal indices, whereas only weak correlations were found with BMI and age.

CONCLUSION

Activation of uPA/uPAR likely plays a role in the pathogenesis of periodontal diseases. uPA/uPAR may have potential utility as candidate salivary biomarkers in periodontal pathogenesis.

Salivaomics: A Revolutionary Non-invasive Approach for Oral Cancer Detection

Salivaomics has emerged as a ground-breaking field in the detection and management of oral cancer (OC), offering a non-invasive, efficient, and patient-friendly alternative to traditional diagnostic methods. This innovative approach leverages the comprehensive molecular insights provided by genomics, transcriptomics, proteomics, metabolomics, and microbiomics. The potential of salivaomics lies in its ability to enable early detection, predict malignant transformation, and monitor treatment outcomes and disease recurrence. Advancing salivary diagnostics necessitates the standardization of saliva collection and processing protocols, identification and validation of robust biomarkers, and development of cutting-edge detection technologies. A single biomarker is unlikely to fulfill all diagnostic requirements; thus, research should focus on developing a panel of biomolecules to enhance diagnostic accuracy and management of OC. Salivaomics stands at the forefront of non-invasive diagnostic methods, with the promise to revolutionize early detection and management of OC. Future research directions should emphasize the integration of multi-omics data for superior biomarker discovery, the development of portable and cost-effective point-of-care devices, and the fostering of interdisciplinary collaborations to drive innovation. Overcoming these challenges will facilitate the translation of salivaomics into routine clinical practice, significantly improving early diagnosis, treatment, and prognosis of OC. This review provides a comprehensive overview of salivaomics, detailing the use of saliva as a diagnostic fluid. It covers saliva collection, preparation, transportation, storage methods, and various analytical techniques. Additionally, the review discusses the current challenges and future directions of this transformative technology, emphasizing its potential to enhance clinical outcomes in OC.

Shaping the future of oral cancer diagnosis: advances in salivary proteomics

INTRODUCTION

Saliva has gained increasing attention in the quest for disease biomarkers. Because it is a biological fluid that can be collected is an easy, painless, and safe way, it has been increasingly studied for the identification of oral cancer biomarkers. This is particularly important because oral cancer is often diagnosed at late stages with a poor prognosis.

AREAS COVERED

The review addresses the evolution of the experimental approaches used in salivary proteomics studies of oral cancer over the years and outlines advantages and pitfalls related to each one. In addition, examines the current landscape of oral cancer biomarker discovery and translation focusing on salivary proteomic studies. This discussion is based on an extensive literature search (PubMed, Scopus and Google Scholar).

EXPERT OPINION

The introduction of mass spectrometry has revolutionized the study of salivary proteomics. In the future, the focus will be on refining existing methods and introducing powerful experimental techniques such as mass spectrometry with selected reaction monitoring, which, despite their effectiveness, are still underutilized due to their high cost. In addition, conducting studies with larger cohorts and establishing standardized protocols for salivary proteomics are key challenges that need to be addressed in the coming years.

Salivary Biomarkers for Oral Cancer Detection: An Exploratory Systematic Review

Different efforts have been made to find better and less invasive methods for the diagnosis and prediction of oral cancer, such as the study of saliva as a source of biomarkers. The aim of this study was to perform a scoping review about salivary molecules that have been assessed as possible biomarkers for the diagnosis of oral squamous cell carcinoma (OSCC). A search was conducted using EBSCO, PubMed (MEDLINE), Scopus, and Web of Science. The research question was as follows: which molecules present in saliva have utility to be used as biomarkers for the early detection of oral cancer? Sixty-two studies were included. Over 100 molecules were assessed. Most of the markers were oriented towards the early diagnosis of OSCC and were classified based on their ability for detecting OSCC and oral potentially malignant disorders (OPMDs), OSCC outcome prediction, and the prediction of the malignant transformation of OPMDs. TNF-α, IL-1β, IL-6 IL-8, LDH, and MMP-9 were the most studied, with almost all studies reporting high sensitivity and specificity values. TNF-α, IL-1β, IL-6 IL-8, LDH, and MMP-9 are the most promising salivary biomarkers. However, more studies with larger cohorts are needed before translating the use of these biomarkers to clinical settings.

MicroRNA-181b attenuates lipopolysaccharide-induced inflammatory responses in pulpitis via the PLAU/AKT/NF-κB axis

OBJECTIVE

This study aimed to investigate the role and underlying mechanisms of microRNA (miRNA)-181b in the inflammatory response in pulpitis.

METHODS

Quantitative reverse-transcription polymerase chain reaction (qRT-PCR), fluorescence in situ hybridization (FISH), and immunofluorescence techniques were used to determine the miRNA-181b and urokinase-type plasminogen activator (PLAU) expression levels in inflamed human dental pulp tissues (HDPTs) and lipopolysaccharide (LPS)-stimulated human dental pulp cells (hDPCs). The targets of miRNA-181b were identified and confirmed using a bioinformatics analysis, RNA sequencing, and dual-luciferase gene reporter assays. The effect of miRNA-181b or PLAU on proinflammatory cytokine expression in hDPCs was examined using qRT-PCR and western blotting. RNA sequencing was conducted to examine the signaling pathways implicated in miRNA-181b-mediated pulpitis. Western blotting and qRT-PCR were used to determine the miRNA-181b /PLAU/AKT/NF-κB signaling axis in pulpitis. A rat pulpitis model was created to observe the histopathological changes in the dental pulp tissue after the topical application of miRNA-181b agomir.

RESULTS

A significant decrease in miRNA-181b and an increase in PLAU were observed in HDPTs compared to the healthy controls, and these two factors showed a negative correlation. MiRNA-181b directly targeted PLAU. The miRNA-181b inhibitor resulted in a significant upregulation of IL-1β, IL-6 and TNF-α, whereas the knockdown of PLAU reversed this proinflammatory effect. Conversely, PLAU overexpression prevented the anti-inflammatory effects of the miRNA-181b mimics. Mechanistically, miRNA-181b inhibited the AKT/NF-κB pathway by targeting PLAU. In vivo application of the miRNA-181b agomir to inflamed pulp tissue alleviated inflammation.

CONCLUSION

MiRNA-181b targets PLAU, negatively regulating pro-inflammatory cytokine expression via the AKT/NF-κB signaling pathway.

Saliva - a new opportunity for fluid biopsy

Saliva is a complex biological fluid with a variety of biomolecules, such as DNA, RNA, proteins, metabolites and microbiota, which can be used for the screening and diagnosis of many diseases. In addition, saliva has the characteristics of simple collection, non-invasive and convenient storage, which gives it the potential to replace blood as a new main body of fluid biopsy, and it is an excellent biological diagnostic fluid. This review integrates recent studies and summarizes the research contents of salivaomics and the research progress of saliva in early diagnosis of oral and systemic diseases. This review aims to explore the value and prospect of saliva diagnosis in clinical application.

Oral Lichen Planus and Oral Squamous Cell Carcinoma share key oncogenic signatures

To investigate similarities in the gene profile of Oral Lichen Planus and Oral Squamous Cell Carcinoma that may justify a carcinogenic potential, we analyzed the gene expression signatures of Oral Lichen Planus and Oral Squamous Cell Carcinoma in early and advanced stages. Based on gene expression data from public databases, we used a bioinformatics approach to compare expression profiles, estimate immune infiltrate composition, identify differentially and co-expressed genes, and propose putative therapeutic targets and associated drugs. Our results revealed gene expression patterns related to processes of keratinization, keratinocyte differentiation, cell proliferation and immune response in common between Oral Lichen Planus and early and advanced Oral Squamous Cell Carcinoma, with the cornified envelope formation and antigen processing cross-presentation pathways in common between Oral Lichen Planus and early Oral Squamous Cell Carcinoma. Together, these results reveal that key tumor suppressors and oncogenes such as PI3, SPRR1B and KRT17, as well as genes associated with different immune processes such as CXCL13, HIF1A and IL1B are dysregulated in OLP.

Advances in the Diagnosis, Monitoring, and Progression of Oral Cancer through Saliva: An Update

The early detection of cancer, and in particular oral cancer, has been a priority objective of study in recent years. Saliva has been proposed as an easy-to-obtain means of providing the necessary information to diagnose malignant lesions in the oral cavity, since it can be obtained very easily and completely noninvasively. There are a number of molecules, known as biomarkers, which may be involved in the malignant transformation of oral lesions, and which have different natures. The involvement of proteins ("proteomics"), metabolites ("metabolomics"), and even certain genes in the structural changes of altered tissue has been investigated in order to establish validated parameters for the early diagnosis of oral cancer. In addition, the development of new analytical assay methods that can reduce costs and obtain better results in terms of sensitivity and specificity has been a key point in recent research in this field. Even though there are numerous biomarkers with results showing high sensitivity and specificity, there is still a need for more studies, with a larger sample and with analytical methods that can constitute a real advance in time and cost. Although salivary biomarkers are a promising new diagnostic tool for oral cancer, for the moment they do not replace biopsy as the "gold standard".