The prognosis of patients with oral squamous carcinoma (OSCC) largely depends on the stage at diagnosis, the 5-year survival rate being approximately 30% for advanced tumors. Early diagnosis, including the detection of lesions at risk for malignant transformation, is crucial for limiting the need for extensive surgery and for improving disease-free survival. Saliva has gained popularity as a readily available source of biomarkers (including cytokines) useful for diagnosing specific oral and systemic conditions. Particularly, the close interaction between oral dysplastic/neoplastic cells and saliva makes such fluid an ideal candidate for the development of non-invasive and highly accurate diagnostic tests. The present review has been designed to answer the question: “Is there evidence to support the role of specific salivary cytokines in the diagnosis of OSCC?” We retrieved 27 observational studies satisfying the inclusion and exclusion criteria. Among the most frequent cytokines investigated as candidates for OSCC biomarkers, IL-6, IL-8, TNF-α are present at higher concentration in the saliva of OSCC patients than in healthy controls and may therefore serve as basis for the development of rapid tests for early diagnosis of oral cancer.

: Background: The aberrant expression of microRNAs (miRNAs) has been associated with several diseases, including cancer, inflammatory, and autoimmune conditions. Interest in salivary miRNAs as non-invasive tools for the diagnosis of malignancies and systemic diseases is rapidly increasing. The present systematic review was developed for answering the question: “Are salivary microRNAs reliable biomarkers for diagnosis of cancer and systemic diseases?” Methods: The application of inclusion and exclusion criteria led to the selection of 11 papers. Critical appraisals and quality assessments of the selected studies were performed through the National Institute of Health “Study Quality Assessment Tool” and the classification of the Oxford Center for Evidence-Based Medicine. Results: Seven studies reported statistically significant correlations between one or more salivary miRNAs and the investigated disease. The critical analysis allowed us to classify only two studies (18.2%) as having “good” quality, the rest being scored as “intermediate” (8; 73%) and “poor” (1; 9%). Evidence exists that salivary miR-940 and miR-3679-5p are reliable markers for pancreatic cancer and that miR140-5p and miR301a are promising molecules for the salivary diagnosis of gastric cancer. Conclusions: Further studies, possibly avoiding the risk of bias highlighted here, are necessary to consolidate these findings and to identify new reliable salivary biomarkers.

Fluorides are compounds that can be found in the minerals of soil with volcanic rocks. Different populations are exposed to high levels of fluorides through drinking water that, due to their chronic intake, cause several types of damage to health. Nails and hair, denominated as recent biomarkers, have been employed for monitoring systemic fluoride from long-term exposure to fluorides. The aim of this study was to perform a systematic review of the use of recent biomarkers for monitoring systemic fluoride levels in exposed populations and verify their validity in the measurement of the fluorine (F⁻) concentration within the body. A digital search was performed in the databases PubMed/Medline, Springer Link, Cochrane, and Scopus of original articles that employed recent biomarkers for monitoring systemic F⁻. Seventeen articles were included in this analysis; the recorded variables were the F⁻ amount in each assessed biomarker, source of exposure, and total daily fluoride intake (TDFI). TDFI was associated with F⁻ in nails and hair, as well as the exposure through drinking water. In conclusion, recent biomarkers are adequate for monitoring the systemic fluoride levels by evaluating the chronic/subchronic exposure through different sources, mainly drinking water, considering nails better than hair for this purpose.