Exosomal Serum Biomarkers as Predictors for Laryngeal Carcinoma †.

Simple Summary: Laryngeal squamous cell carcinomas (LSCC) are the third most common type of head and neck cancer. Approximately 40% of LSCC cases present with locally advanced carcinomas at diagnosis. The poor prognosis is mainly attributed to late diagnosis. Biomarkers capable of predicting LSCC at early stages are needed. We identified and validated exosomal insulin-like growth factor binding protein 7 (IGFBP7) and Annexin A1 (ANXA1) as promising exosomal biomarkers for LSCC detection. Background: The lack of screening methods for LSCC is a critical issue, as treatment options and the treatment outcome greatly depend on the stage of LSCC at initial diagnosis. Therefore, the objective of this study was to identify potential exosomal serum biomarkers that can diagnose LSCC and distinguish between early- and late-stage disease. Methods: A multiplexed proteomic array was used to identify differentially expressed proteins in exosomes isolated from the serum samples of LSCC patients compared to the control group (septorhinoplasty, SRP). The most promising proteins for diagnosis and differentiation were calculated using biostatistical methods and were validated by immunohistochemistry (IHC), Western blots (WB), and ELISA. Results: Exosomal insulin-like growth factor binding protein 7 (IGFBP7) and Annexin A1 (ANXA1) were the most promising exosomal biomarkers for distinguishing between control and LSCC patients and also between different stages of LSCC (fold change up to 15.9, p < 0.001 for all). Conclusion: The identified proteins represent potentially novel non-invasive biomarkers. However, these results need to be validated in larger cohorts with a long-term follow-up. Exosomal biomarkers show a superior signal-to-noise ratio compared to whole serum and may therefore be an important tool for non-invasive biomarker profiling for laryngeal carcinoma in the future. [ABSTRACT FROM AUTHOR]