A Cross-Sectional Pilot Analysis of Downregulated Circulating MicroRNAs in Laryngeal Cancer

Background and Objectives: Despite notable advances in diagnosing and managing laryngeal cancer, the disease continues to present challenges, particularly in the advanced stages. Circulating microRNAs (miRNAs) are increasingly recognized as accessible biomarkers for cancer detection and follow-up. This exploratory study centers on identifying and evaluating miRNAs that are specifically downregulated in laryngeal carcinoma patients, aiming to clarify their clinical relevance in distinguishing pre- and post-therapeutic states. Methods: A total of 30 patients with laryngeal cancer provided paired blood samples before and after undergoing surgical or non-surgical treatment. To reduce variability and resource demand, each set of 10 samples was pooled into three pre-treatment groups (P1, P2, and P3) and three corresponding post-treatment groups (C1, C2, and C3). Total RNA, including miRNAs, was isolated from both plasma and exosomes, followed by qPCR-based profiling (Qiagen platform). Downregulated miRNAs were singled out through statistical comparisons using Mann-Whitney U tests; receiver operating characteristic (ROC) analyses and logistic regression were further applied to assess diagnostic utility. Results: Seven miRNAs demonstrated significant downregulation in the pre-treatment samples (fold changes ranging from 0.20 to 0.64, p < 0.05). Notably, hsa-miR-107 and hsa-let-7a-5p both showed marked reductions of approximately fivefold (p < 0.01), suggesting a strong association with active tumor presence. In ROC analysis, hsa-miR-107 achieved an area under the curve (AUC) of 0.78 (95% CI: 0.62-0.90) with 72% sensitivity and 74% specificity in differentiating pre- from post-treatment states. A logistic regression model incorporating downregulated candidates produced odds ratios between 0.52 and 0.64 (p < 0.05), pointing to their potential additive value in clinical decision-making. Conclusions: These preliminary findings indicate that certain miRNAs, when suppressed in circulation, may be linked to the oncogenic milieu of laryngeal cancer. Confirming these observations in larger, multicenter investigations is critical, but this pilot work underscores the promise of downregulated miRNAs as biomarkers of disease activity and potential guides to therapy response.