Exosomal Biomarkers for Prognosis in Oral Squamous Cell Carcinoma-A Systematic Review of Emerging Technologies.

Background: Oral squamous cell carcinoma (OSCC) is a significant health issue because of its aggressive nature and poor prognosis during the advanced stages. Exosomal biomarkers have emerged as promising entities for facilitating an enhanced existing assessment of diagnosis and prognosis in OSCC, particularly in monitoring the noninvasive behavior of tumors. The authors tried to assess the potential role of these exosomal biomarkers in the prognosis of OSCC through this systematic review.

Methods: Seven databases, PubMed, Scopus, Web of Science, Embase, Cochrane Library, CINAHL, and ProQuest, were searched systematically. Boolean operators, along with MeSH terms, were utilized for refining the search strings to retrieve the appropriate studies. The authors included studies focusing on exosomal biomarkers derived from OSCC tissues or cell lines, with emphasis on their potential as a prognostic.

Results: We included 7 studies that probed the role of miRNAs, lncRNAs, and proteins in exosomes. A few particular miRNAs, such as miR-155, miR-21, miR-126, and miR-130a showed significant correlation with the patients' outcomes along with the progression of OSCC. These miRNAs continuously showed association with pathways having activities related to the promotion of tumor growth, regulation of the immune system, and angiogenesis. Interestingly, the studies on proteins like Arginase-1 and CKAP4 demonstrated significance in metastasis via exosomes and could be exploited in the risk assessment for metastasis. Another group of lncRNAs screened in exosomal contents has opened the exciting possibility of uncovering the functions of noncoding RNAs in the pathogenesis of OSCC.

Conclusions: Our results conclude that exosomal biomarkers, including miRNAs, lncRNAs, and proteins, have great potential to improve the accuracy of prognosis and thus outcomes in OSCC. Some miRNAs were proven to be particularly instrumental for non-invasive diagnostics, whereas proteins and lncRNAs were more informative concerning complicated mechanisms of progression. The above inconsistency in molecular targets between the studies indicates that exosomes play a complex role in OSCC and future studies should focus on combining these different types of biomarkers for further enhancement of potential clinical applications and management of OSCC patients.