Salivary Biomarkers: Diagnosis, Monitoring, and Prognosis of Systemic Diseases Through Saliva

Saliva has emerged as a powerful, non-invasive diagnostic fluid, offering a promising alternative to blood for the detection and monitoring of systemic diseases. Rich in proteins, nucleic acids, hormones, and microbiota, salivary biomarkers reflect physiological and pathological states throughout the body. Advances in omics technologies and biosensor platforms have enabled the identification of salivary signatures associated with conditions such as oral, head and neck, and other cancers, cardiovascular disease, diabetes, and neurodegenerative disorders. Of particular relevance is the role of salivary biomarkers in the early detection of oral cancer and oral potentially malignant disorders (OPMDs), where the direct contact between saliva and affected tissues creates a uniquely informative diagnostic window. Saliva collection is simple, stress-free, and cost-effective, making it ideal for repeated sampling and large-scale screening. Moreover, salivary diagnostics support real-time disease monitoring and prognosis, enhancing personalised medicine approaches. As research deepens, the integration of salivary biomarkers into clinical practice holds significant potential for early detection, disease progression tracking, and therapeutic response assessment across a wide spectrum of oncologic and non-oncologic systemic illnesses.

Although salivary biomarkers offer a non-invasive, accessible, and cost-effective approach to diagnosing and monitoring systemic diseases, their clinical application remains limited. Major challenges include variability in saliva composition, lack of standardised collection and processing protocols, and insufficient validation of biomarkers across diverse populations and disease stages. These issues hinder reproducibility and the establishment of reliable diagnostic thresholds. In oncology, and oral cancer in particular, additional challenges arise from distinguishing tumour-derived biomarkers from those associated with inflammation, infection, or other comorbidities. To overcome these barriers, this research aims to identify and validate robust, disease-specific salivary biomarkers using standardised methodologies. Recent advances in high-throughput omics technologies, such as proteomics, transcriptomics, and metabolomics, combined with artificial intelligence and machine learning, have significantly improved the sensitivity and specificity of biomarker detection. Furthermore, the development of portable biosensors and point-of-care diagnostic devices is accelerating the integration of salivary diagnostics into clinical practice, including chair-side screening for oral malignancies and OPMDs. This research will build on these innovations to enhance early detection, real-time monitoring, and personalised treatment strategies for a range of systemic diseases, with a dedicated focus on oncologic conditions affecting the oral cavity.

The goal of this Research Topic is to advance the field of salivary diagnostics by fostering multidisciplinary efforts to address critical gaps, improve standardisation, and ultimately support the implementation of saliva-based tests in clinical routine. By bridging the communities of salivary biomarker research and oral oncology, we aim to accelerate the translation of salivary biomarkers into impactful tools for precision healthcare, from population-level oral cancer screening to individualised management of systemic diseases.

We welcome contributions that explore the breadth of this evolving field, including but not limited to:
- Discovery and validation of robust, disease-specific salivary biomarkers, with emphasis on oncologic conditions and oral cancer
- Salivary biomarkers for the early detection of oral cancer and oral potentially malignant disorders
- Salivary signatures for prognosis, treatment response monitoring, and recurrence surveillance in oral and head and neck cancers
- Standardisation of saliva collection, processing, and analytical protocols
- Application of omics approaches (proteomics, transcriptomics, metabolomics, genomics, epigenomics, etc.) in salivary diagnostics
- Development and evaluation of biosensors and point-of-care diagnostic tools, including chair-side screening devices for oral malignancies
- Integration of artificial intelligence and machine learning for biomarker analysis and interpretation
- Comparative studies on the effectiveness of salivary versus blood-based and tissue-based diagnostics
- Addressing regulatory, ethical, and implementation challenges for clinical translation of salivary diagnostics
- Clinical applications in early disease detection, monitoring, and personalised treatment

Article types and fees

This Research Topic accepts the following article types, unless otherwise specified in the Research Topic description:

• Brief Research Report
• Case Report
• Classification
• Clinical Trial
• Community Case Study
• Curriculum, Instruction, and Pedagogy
• Data Report
• Editorial
• FAIR² Data
• ... View all formats

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Article types

This Research Topic accepts the following article types, unless otherwise specified in the Research Topic description:

• Brief Research Report
• Case Report
• Classification
• Clinical Trial
• Community Case Study
• Curriculum, Instruction, and Pedagogy
• Data Report
• Editorial
• FAIR² Data
• FAIR² DATA Direct Submission
• General Commentary
• Hypothesis and Theory
• Methods
• Mini Review
• Opinion
• Original Research
• Perspective
• Policy and Practice Reviews
• Policy Brief
• Review
• Study Protocol
• Systematic Review
• Technology and Code

Keywords: salivary biomarkers, systemic diseases, non-invasive diagnostics, omics technologies, biosensors, personalized medicine

Important note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.