The current study investigated the expression signatures of miRNAs in lung adenocarcinoma (LUAD) and squamous cell lung carcinoma (LUSC). miRNA profiling was performed using microarray in 12 LUAD and 12 LUSC samples and adjacent normal tissues. In LUAD, 107 miRNAs were significantly deregulated, whereas 235 miRNAs were deregulated in LUSC. Twenty-six miRNAs were common between the 2 cancer subtypes and 8 were prioritized for validation, in addition to 6 subtype-specific miRNAs. The RT-qPCR validation samples included 50 LUAD, 50 LUSC, and adjacent normal tissues. Eight miRNAs were validated in LUAD: 3 upregulated - miR-7-5p, miR-375-5p, miR-6785-3p, and 5 downregulated - miR-101-3p, miR-139-5p, miR-140-3p, miR-144-3p, miR-195-5p. Ten miRNAs were validated in the LUSC group: 3 upregulated - miR-7-5p, miR-21-3p, miR-650, and 7 downregulated - miR-95-5p, miR-140-3p, miR-144-3p, miR-195-5p, miR-375, miR-744-3p, and miR-4689-3p. Reactome pathway analysis revealed that the target genes of the deregulated miRNAs in LUAD were significantly enriched in cell cycle, membrane trafficking, gene expression processes, and EGFR signaling, while in LUSC, they were enriched in the immune system, transcriptional regulation by TP53, and FGFR signaling. This study identified distinct miRNA profiles in LUSC and LUAD, which are common and specific miRNAs that could be further investigated as biomarkers for diagnosis and prognosis.

Laryngeal squamous cell carcinoma is a common malignancy in men. Bulgaria is one of the countries in Europe with the highest incidence and mortality rates of the aggressive, severe disease of laryngeal cancer. Proven etiological factors are the abuse of tobacco and alcohol beverages. Despite the progress of technologies of multimodal medical treatment, survival rates have not reached satisfactory levels. Over the last few decades, scientific and clinical research data have led to a growing interest in exploring potential biomarkers. In the last years, non-coding RNAs have become promising biomarkers. They are important key regulators in both normal and tumour specific biological processes as well as in the response to environmental factors and treatment, including chemo- and radiotherapy. Studies have shown ectopic expression of a number of ncRNAs in laryngeal cancer. Published data provide evidence of the lncRNAs and miRNAs that could help us better understand complex carcinogenesis in laryngeal cancer and would provide reliable diagnostic, prognostic and predictive biomarkers.

Introduction: Recently, miRNAs have become popular molecules used as non-invasive biomarkers in cancer diseases. Aim: The aim of the study was to explore the expression of four miRNAs isoforms: miR-31-3p, miR-196a-5p, miR-210-3p and miR-424-5p in plasma and tissue samples from patients with advanced laryngeal squamous cell carcinoma (LSCC) and healthy controls. Materials and methods: Fresh-frozen tumour and normal laryngeal tissue as well as plasma samples were obtained from 22 patients diagnosed with advanced LSCC. The control group included plasma samples from 21 cancer-free volunteers. Total RNA (including miRNAs) extraction, reverse transcription and real time qPCR were the laboratory techniques used in the study. The obtained results were analyzed using SPSS software v. 23. Results: We found that miR-31-3p, miR-196a-5p, and miR-210-3p levels were significantly elevated in laryngeal tumour tissue, but only the levels of miR-31-3p and miR-196a-5p were significantly upregulated in the plasma LSCC target group. Positive correlation was obtained for miR-31-3p (rs=0.443, p=0.039) and miR-196a-5p (rs=0.548; p=0.008) between plasma and adjacent tumour tissue LSCC samples. ROC analyses were used to evaluate the discriminative power of both miRNAs alone and in combination. The combination of miR-31-3p and miR-196a-5p showed best results with AUC=0.978 (95% CI: 0.945–1.000, p<0.001) with 100% sensitivity and 81% specificity at cut-off: RQ=2.99. Conclusions: Based on this miR-31-3p and miR-196a-5p are proposed as potential biomarkers for validation in larger LSCC group and could be included in a non-invasive miRNAs set for detection of advanced LSCC.

Field cancerization is a fundamental paradigm in tumorigenesis, emphasizing that carcinogenesis begins long before the appearance of clinically detectable lesions and often precedes recognizable premalignant changes. A direct manifestation of this process is the molecular dysregulation observed in the peritumoral mucosa—histologically normal-appearing tissue that nonetheless exhibits genetic and epigenetic alterations similar to those of the adjacent tumor. This review summarizes current evidence on the molecular alterations shared between tumor tissue and peritumoral mucosa in HNSCC and evaluates their potential as biomarkers for defining molecular margins and improving surgical precision. A literature search was conducted in PubMed using combinations of the keywords “peritumor,” “laryngeal”, “HNSCC,” and “field cancerization.” Studies were included if they directly compared tumor tissue with peritumoral mucosa and, preferably, a third set of distant normal control samples. Only nine studies met the inclusion criteria, highlighting the scarcity of focused research in this area. Reported biomarkers exhibiting comparable dysregulation in both tumor and peritumor tissues include MDM2, E2F2, CDKN2A/p16, ETS-1, MGMT, and multiple microRNAs (e.g., miR-21, miR-96-5p, miR-145-5p). These molecular signatures demonstrate the presence of a biologically altered field extending beyond histologically defined tumor margins. Peritumoral mucosal dysregulation, as a consequence of field cancerization, underscores the need to redefine surgical margins at the molecular level. The identification and validation of biomarkers reflecting this continuum could enable the establishment of molecular margins—improving risk assessment, reducing local recurrence, and advancing personalized oncologic surgery in HNSCC. Standardizing definitions and sampling protocols for “normal adjacent tissue” remains essential for future translational research.

During the past decade, a vast number of studies were dedicated to unravelling the obscurities of non-coding RNAs in all fields of the medical sciences. A great amount of data has been accumulated, and consequently a natural need for organization and classification in all subfields arises. The aim of this review is to summarize all reports on microRNAs that were delineated as prognostic biomarkers in laryngeal carcinoma. Additionally, we attempt to allocate and organize these molecules according to their association with key pathways and oncogenes affected in laryngeal carcinoma. Finally, we critically analyze the common shortcomings and biases of the methodologies in some of the published papers in this area of research. A literature search was performed using the PubMed and MEDLINE databases with the keywords “laryngeal carcinoma” OR “laryngeal cancer” AND “microRNA” OR “miRNA” AND “prognostic marker” OR “prognosis”. Only research articles written in English were included, without any specific restrictions on study type. We have found 43 articles that report 39 microRNAs with prognostic value associated with laryngeal carcinoma, and all of them are summarized along with the major characteristics and methodology of the respective studies. A second layer of the review is structural analysis of the outlined microRNAs and their association with oncogenes and pathways connected with the cell cycle (p53, CCND1, CDKN2A/p16, E2F1), RTK/RAS/PI3K cascades (EGFR, PI3K, PTEN), cell differentiation (NOTCH, p63, FAT1), and cell death (FADD, TRAF3). Finally, we critically review common shortcomings in the methodology of the papers and their possible effect on their results.