4.1. Analysis of Findings
This study set out to identify upregulated miRNAs in laryngeal cancer patients and to explore their clinical utility for diagnostics and treatment monitoring. The data show that several miRNAs, particularly miR-424-5p and miR-186-5p, exhibited substantial elevation preoperatively and trended toward normalization post-treatment. Correlation analyses further suggest that these miRNAs may belong to overlapping regulatory networks, though the exact mechanistic underpinnings remain to be elucidated. Compared to traditional biomarkers, miRNAs offer distinct advantages: stability in circulation, ease of quantification, and the potential to reflect ongoing tumor activity. Consequently, upregulated miRNAs might provide clinicians with a dynamic readout of disease status, allowing earlier detection of relapse or incomplete tumor eradication. Other findings underscored that these markers can discriminate between active and treated states with moderate to high sensitivity and specificity. While individual miRNAs rarely provide perfect diagnostic clarity, a panel-based approach could significantly boost accuracy. These insights strengthen the rationale for including miRNAs in multi-parameter predictive models that also incorporate imaging and histopathological data.
Table 7 provides an overview of the key biological pathways and processes potentially modulated by each upregulated miRNA, as identified through in silico analyses (e.g., target prediction databases and pathway enrichment tools). A recurring theme is the regulation of cell cycle and apoptosis-related pathways, evident for miR-424-5p [
22], miR-15b-5p [
23], and miR-34a-5p [
24]. This aligns with well-established oncogenic mechanisms in which dysregulated control of proliferation and programmed cell death fosters malignant progression.
Notably, miR-186-5p appears to intersect with pathways involved in stress response and angiogenesis, such as MAPK and Notch [
25]. Such pathways can be critical in tumor adaptation to microenvironmental pressures. Similarly, miR-93-3p [
26] and miR-200c-3p are linked to epithelial–mesenchymal transition (EMT) and invasion, processes that facilitate metastasis. These connections hint that elevated miR-93-3p [
27] or miR-200c-3p [
28] might signal a transition to a more invasive phenotype, which is crucial knowledge for risk stratification and targeted therapies.
The predicted involvement of miR-133a-3p [
29] in ERK/MAPK and Myc pathways underscores its possible regulatory influence on tumor growth and differentiation. Though functional validation remains essential, these in silico insights pave the way for targeted experimental work. Specifically, if certain miRNAs indeed govern key signaling nodes, they may become focal points for novel therapeutics or combination regimens. Overall, the pathways summarized here underscore how upregulated miRNAs could simultaneously serve as biomarkers of aggressive cancer biology and as potential levers for future precision oncology interventions.
In a similar manner, the study by Li Chen et al. [
30] explored the impact of microRNA-141 (miR-141) on epithelial–mesenchymal transition (EMT) and lymph node metastasis in laryngeal cancer through the modulation of the Homeobox C6 (HOXC6)-dependent TGF-β signaling pathway. The researchers discovered that upregulation of miR-141 led to a downregulation of HOXC6 and subsequent inhibition of the TGF-β signaling pathway, which effectively repressed EMT and reduced the viability, migration, and invasion abilities of laryngeal cancer cells, as well as tumor growth in vivo. They further demonstrated that miR-141 upregulation notably curbed lymph node metastasis, suggesting a significant therapeutic potential in managing laryngeal cancer.
On the other hand, the study by Libing Guo et al. [
31] investigated the expression levels of miRNA-145 and miRNA-218 in the serum of laryngeal cancer patients and their correlation with clinicopathological parameters and prognosis. Their findings indicated that lower serum levels of miRNA-145 and miRNA-218 were associated with poorer prognoses. Notably, patients in the high-expression group for these miRNAs demonstrated a median survival time of 30 months, compared to 26 months in the low-expression group, establishing these miRNAs as potential prognostic indicators. Both studies underscore the critical role of miRNAs in laryngeal cancer progression and prognosis, highlighting their utility in developing targeted therapeutic strategies and improving patient survival outcomes.
Moreover, the study by Fatma Ruya Tuncturk et al. explored the potential of microRNAs as transformation biomarkers in laryngeal lesions, distinguishing between benign, premalignant, and malignant stages [
32]. They identified that certain miRNAs, such as Hs_miR-183_5p, Hs_miR-155_5p, and Hs_miR-106b_3p, were significantly upregulated in premalignant lesions compared to benign ones, with fold increases of 4.16, 2.72, and 3.01, respectively. As lesions progressed to malignancy, these upregulations continued, indicating a gradient of expression correlating with the severity of the lesion. Furthermore, miRNAs like Hs_miR-21_5p, Hs_miR-218_3p, and Hs_miR-210_3p exhibited substantial upregulation solely in the malignant stage compared to benign tissues, suggesting their specific association with fully transformed cancerous cells.
In parallel, the study by Pei Li et al. investigated the regulation and role of miR-1205 in LSCC, finding it notably downregulated in LSCC samples compared to adjacent non-tumorous tissues [
33]. The authors further detailed how miR-1205 downregulation was linked with advanced clinical stage and poor prognosis, whereas its overexpression mitigated migration, growth, and invasion of LSCC cells. The study also highlighted a reciprocal regulatory mechanism between miR-1205 and E2F1, a transcription factor that was found to be inversely related to miR-1205 levels and associated with poorer clinical outcomes. Both studies underscore the nuanced roles of specific miRNAs in the progression from benign to malignant states and their potential utility in clinical diagnostics and prognostics, reflecting the complexity and promise of miRNA-based markers in cancer management.
Genetic polymorphisms in miRNA biogenesis and function can modulate circulating miRNA levels, influencing both their expression and regulatory capacities across individuals. Given that our pilot study did not analyze these genetic variations, the observed miRNA alterations may not be generalizable to populations with different polymorphic profiles. For example, if multiple participants share a common variant that impacts miRNA processing enzymes, the resulting upregulation or downregulation could be population specific. The absence of genotyping data therefore constrains our ability to interpret whether the detected miRNA shifts reflect inherent tumor biology or an interplay between genetics and disease state. Future investigations should incorporate genetic screening to ensure more robust conclusions on the role of miRNAs in laryngeal cancer and improve the translatability of findings across diverse cohorts [
34,
35,
36].
The miRNAs highlighted in this study, while showing a clear association with laryngeal cancer, have not been examined here for their mechanistic roles in tumor biology. Elucidating how each miRNA modulates gene expression—whether by fostering proliferation, enabling metastasis, or instead acting as a gatekeeper against tumor progression—is essential for interpreting their clinical significance. Some may drive oncogenic pathways, whereas others could inhibit critical steps in tumorigenesis. By delineating these specific targets and pathways, future research can more precisely determine if such miRNAs might serve as viable therapeutic targets or molecular indicators of disease status.
Our findings indicate that these upregulated miRNAs show promise as potential biomarkers for detecting and monitoring laryngeal cancer, but the path from pilot data to routine clinical application remains multifaceted. Rather than supplanting established diagnostic methods, these miRNAs would likely augment existing tools—such as imaging and histopathology—providing an additional layer of molecular specificity. The next steps involve conducting larger-scale, multicenter trials to confirm our results, refining cut-off thresholds for diagnostic accuracy, and performing longitudinal monitoring to see how miRNA levels correlate with clinical outcomes over time. In parallel, targeted functional studies could verify whether modulating these miRNAs affects tumor behavior, thereby validating their mechanistic role in laryngeal cancer progression.
A longitudinal approach tracking miRNA levels at multiple time points would likely yield more nuanced insights into their roles in disease progression and therapy response. Such temporal data could capture dynamic fluctuations, as individual patients may exhibit unique expression patterns in response to different treatments. By examining miRNA shifts throughout the entire course of the disease, researchers can better understand whether these biomarkers reflect ongoing tumor biology or merely static snapshots of disease state. Deepening the exploration of the molecular pathways that these miRNAs regulate would significantly enhance our insight into their roles in laryngeal cancer. Pathway enrichment analyses, coupled with knockdown and overexpression experiments, could pinpoint the specific oncogenic or tumor-suppressive mechanisms of each miRNA.
4.2. Study Limitations
Several limitations should be addressed when interpreting these results. First, the pilot design and modest sample size restrict the generalizability of our findings. Pooling patient samples, while cost-effective and practical for an initial screening, can obscure individual-level variability that may be clinically meaningful. Second, the study examined only a single postoperative time window (2–4 weeks), potentially missing ongoing fluctuations in miRNA expression related to wound healing, inflammation, or longer-term tumor recurrence. Third, despite analyzing both free-circulating and exosomal fractions, we did not explore other epigenetic modifications (e.g., DNA methylation, long non-coding RNAs), which could offer a more complete molecular picture. Fourth, our in silico pathway predictions, though informative, are hypothetical until experimentally validated. Moreover, the study assesses miRNA levels at a single postoperative time point (2–4 weeks), which may not capture dynamic changes in expression over time. Finally, factors such as smoking status, comorbidities, or genetic polymorphisms in miRNA biogenesis might confound expression patterns but were not deeply interrogated here. Larger, longitudinal, and multicenter trials are necessary to confirm the diagnostic and prognostic potential of these upregulated miRNAs.