MiR-449a: A Novel Biomarker for Diagnosis, Prognosis, and Treatment Response in Locally Advanced Laryngeal Squamous Cell Carcinoma

Background: Locally advanced laryngeal squamous cell carcinoma (LA-LSCC) presents clinical challenges due to limited non-invasive biomarkers. This study aimed to evaluate miR-449a as a diagnostic and prognostic biomarker in LA-LSCC. Methods: miR-449a expression was analyzed in tumor tissues, adjacent normal tissues, and serum from 81 LA-LSCC patients and 50 controls using qRT-PCR. Diagnostic accuracy (ROC curves), clinicopathological associations, survival outcomes (Kaplan-Meier), and treatment response dynamics were assessed. Results: miR-449a was significantly downregulated in LA-LSCC tissues (p < 0.0001) and serum (p < 0.0001), with a strong tissue-serum correlation (R² = 0.988). Tissue miR-449a demonstrated robust diagnostic accuracy (AUC = 0.857), while serum showed moderate accuracy (AUC = 0.734). High miR-449a expression correlated with favorable clinicopathological features and improved survival (median overall survival: 67.82 vs. 23.74 months; p = 0.0012). Multivariate analysis confirmed miR-449a as an independent prognostic factor (p < 0.001). miR-449a levels increased post-treatment, particularly in responders to chemotherapy/radiation (p < 0.0001). Conclusion: miR-449a serves as a non-invasive biomarker for LA-LSCC diagnosis, prognosis, and treatment monitoring. Its dynamic expression highlights potential for risk stratification and therapy response prediction, warranting further validation in larger cohorts.