Nicotine downregulates miR-375-3p via neurotrophic tyrosine receptor kinase 2 to enhance the malignant behaviors of laryngopharyngeal squamous epithelial cells.

Nicotine exposure from smoking constitutes a significant global public health concern. Furthermore, smoking represents a pivotal risk factor for head and neck squamous cell carcinoma (HNSCC). However, the influence of nicotine on HNSCC remains relatively underexplored. Our aim was to unravel the molecular mechanisms that underlie the effect of nicotine on the metastatic cascade of HNSCC. In this study, we discovered a significant association between smoking and HNSCC metastasis and prognosis. Nicotine significantly enhanced HNSCC cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) in vitro. Analysis of TCGA-HNSCC and FDEENT-HNSCC cohorts revealed reduced miR-375-3p levels in HNSCC tumor tissues, particularly among current smokers. Additionally, miR-375-3p level was strongly correlated with both lymph node metastasis and tumor stage. By downregulating miR-375-3p, nicotine promotes HNSCC cell metastasis in vitro and hematogenous metastatic capacity in vivo. Utilizing transcriptomic sequencing, molecular docking, dual-luciferase reporter assay, and fluorescence in situ hybridization (FISH), we demonstrated that miR-375-3p specifically binds to 3' untranslated region (3'UTR) of NTRK2 mRNA. Thus, this study uncovers a novel nicotine-induced mechanism involving miR-375-3p-mediated NTRK2 targeting, which promotes HNSCC metastasis. These findings have implications for improving the prognosis of patients with HNSCC, especially in smokers.

Association Between Alcohol Dehydrogenase Polymorphisms and the Recurrence of Laryngeal Carcinoma.

OBJECTIVES: Alcohol consumption is closely associated with prognosis for laryngeal squamous cell carcinoma (LSCC) patients. As key enzymes in ethanol metabolism, proteins in the alcohol dehydrogenase (ADH) family make for valuable targets to establish a novel predictive nomogram model. This study attempts to do so by focusing on the single nucleotide polymorphisms (SNPs) of ADH1B and ADH1C in LSCC. METHODS: Sixty eight LSCC patients that were followed up for more than 10 years were retrospectively analyzed. Endpoints of the current study included disease-free survival and overall survival. Survival analyses were performed using the Kaplan-Meier method and evaluated by log-rank test. The prognostic value of eight ADH1B SNPs and three ADH1C SNPs were evaluated using univariate and multivariate Cox regression analyses. A nomogram model for disease-free survival was established and evaluated using the receiver operating characteristic curve, the C-index, and a calibration plot. RESULTS: Significant association was exhibited between rs17033 (p < 0.001) and rs1229984 (p = 0.002) with an increase in LSCC recurrence rate on Kaplan-Meier curves. Multivariate logistic regression analysis revealed that the rs17033 polymorphism of ADH1B was independently associated with an increased risk of LSCC recurrence (HR = 3.325, 95% CI = 1.684-6.566, p = 0.001). Based on these findings, a prognostic nomogram of LSCC patients involving ADH1B rs17033 was constructed. CONCLUSION: This study has demonstrated an independent association between ADH1B gene variants and the recurrence of LSCC. A nomogram model based on rs17033 of ADH1B, age, T, and N stages were successfully developed for the first time to predict the probability of recurrence in LSCC patients. LEVEL OF EVIDENCE: 3 Retrospective cohort study Laryngoscope, 132:2169-2176, 2022.