AFAP1‐AS1 is a long non‐coding RNA that is associated with tumorigenesis and poor prognosis in a variety of cancers. We have been suggested that AFAP1‐AS1 increases tumorigenesis in laryngeal carcinoma specifically by enhancing stemness and chemoresistance. We assessed AFAP1‐AS1 expression in human laryngeal specimens, paired adjacent normal tissues and human HEp‐2 cells. Indeed, we found not only that AFAP1‐AS1 was up‐regulated in laryngeal carcinoma specimens and cells, but also that stemness‐associated genes were overexpressed. Silencing of AFAP1‐AS1 promoted HEp‐2 cell chemoresistance under cisplatin treatment. Expression of AFAP1‐AS1 was increased in drug‐resistant Hep‐2 cells. We then probed the mechanism of AFAP1‐AS1 activity and determined that miR‐320a was a potential molecular target of AFAP1‐AS1. Luciferase reporter and qRT‐PCR assays of AFAP1‐AS1 and miR‐320a levels in human specimens and cell cultures indicated that AFAP1‐AS1 negatively regulates miR‐320a. To discover the molecular mechanism of miR‐320a, we again used the DIANA Tools algorithm to predict its genetic target, RBPJ. After cloning the 3′‐untranslated regions (3′‐UTR) of RBPJ into a luciferase reporter, we determined that miR‐320a did in fact reduce RBPJ mRNA and protein levels. Ultimately, we determined that AFAP1‐AS1 increases RBPJ expression by negatively regulating miR‐320a and RBPJ overexpression rescues stemness and chemoresistance inhibited by AFAP1‐AS1 silencing. Taken together, these results suggest that AFAP1‐AS1 can serve as a prognostic biomarker in laryngeal carcinoma and that miR‐320a has the potential to improve standard therapeutic approaches to the disease, especially for cases in which cancer cell stemness and drug resistance present significant barriers to effective treatment.

High incidences of laryngeal cancer have been reported recently. Increasing our understanding of the molecular mechanisms underlying this malignancy could reveal more effective approaches to treating laryngeal cancer patients and so improve their prognoses. In this study, we explored the biological effects of miR-217 on laryngeal cancer. miR-217 potently inhibited multiple metastatic traits, including cell migration, invasion, proliferation, apoptosis, and EMT, as well as angiogensis. These effects were achieved through downregulation of the miR-217 target gene, AEG-1 and PD-L1. Clinical expression and animal model studies further confirmed our results. These findings provide new insight into the physiological effects of miR-217 in laryngeal cancer and its potential therapeutic use.

Aims: This study aimed to investigate the expression of EphA7 in human laryngeal squamous cell carcinoma (LSCC) tissues and disclose the potential roles and molecular mechanisms of EphA7 in LSCC. Methods: In the present study, we examined EphA7 expression and its function and mechanism in LSCC. EphA7 expression levels were investigated by quantitative real-time PCR (qRT-PCR), western blotting, and immunohistochemistry in a panel of 35 LSCC patient cases. To investigate the potential mechanism of EphA7 in human laryngeal cancer, we employed EphA7 siRNA to knockdown EphA7 expression in LSCC cell line Hep-2 and AMC-HN-8. Subsequently, MTT, TUNEL, qRT-PCR, and western blotting were performed to disclose the roles of EphA7 on proliferation, invasion and migration, and apoptosis in LSCC cell line Hep-2 and AMC-HN-8. Results: Depletion of EphA7 remarkably inhibited the proliferation and invasion of Hep-2 and AMC-HN-8 cells in comparison to control and EphA7 siRNA negative control (NC)-transfected cells. TUNEL staining assay demonstrated that, compared with the control group, the rate of apoptosis in the EphA7 siRNA group was significantly increased. In addition, knockdown of EphA7 in Hep-2 or AMC-HN-8 cells markedly decreased the expression of EphA7 and PTEN, which could contribute to apoptosis. However, the bpV(phen), a PTEN inhibitor, could attenuate anti-proliferation and pro-apoptotic effects of EphA7 siRNA in Hep-2 and AMC-HN-8 cells. Conclusion: Up-regulation of EphA7 was observed in human LSCC samples and down-regulation of EphA7 effectively suppressed laryngeal carcinoma cell growth and promoted its apoptosis. Thus, EphA7 has a critical role in modulating cell growth and apoptosis, which serves as a potential therapeutic target in human LSCC.

Functional, noncoding RNA of about 200 nucleotides in length are known as long noncoding RNA (lncRNA). Advances in -omics have revolutionized the information with respect to the coding and noncoding regions of the genome. Several studies have illustrated the role of lncRNA in cell growth and cancer. Profiling and bioinformatic studies of laryngeal cancer has identified LINC-PINT as one of the lncRNA. However, the functional aspects of the deregulation have not been studied in laryngeal tumors. In this study, LINC-PINT expression in normal and tumor tissues were studied. Using a bioinformatic approach, microRNA (miRNA) targets of LINC-PINT and gene targets of the miRNA were determined. The impact of LINC-PINT on cell proliferation and chemoresistance was determined. Further through a set of silencing and reexpression studies phenotype rescue was studied. LINC-PINT expression was downregulated in laryngeal tumors. LINC-PINT targeted miR-425-5p by three sites. miR-425-5p also targeted PTCH1 a protein of the Hedgehog pathway. Downregulation of LINC-PINT was associated with increased cancer stemness and chemoresistance to cisplatin. Our results indicate a probable role of LINC-PINT in the pathology of laryngeal tumors. LINC-PINT re-expression in laryngeal tumors may be explored for reversion of cancer cell stemness and also for rescue of drug resistance phenotype.

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