Long non-coding RNA NEAT1 promotes the malignancy of laryngeal squamous cell carcinoma by regulating the microRNA-204-5p/SEMA4B axis

Laryngeal squamous cell carcinoma (LSCC) is a highly invasive malignant tumor in the head and neck area. As an oncogene, long non-coding RNA (lncRNA) nuclear enriched abundant transcript 1 (NEAT1) promotes cell proliferation, migration and invasion several types of cancer. The present study aimed to reveal the effects of NEAT1 on the progression of LSCC. Reverse transcription-quantitative PCR (RT-qPCR) was used to detect relative mRNA expression levels of NEAT1, microRNA (miR)-204-5p and semaphorin (SEMA) 4B. Kaplan-Meier analysis was used to analyze overall survival times. RNA in-situ hybridization (ISH) exhibited the distribution of NEAT1 and miR-204-5p in tissues. RNA fluorescence ISH was used to analyze the distribution of NEAT1 and miR-204-5p in the cells. Western blot analysis was used to detect the expression level of target proteins. Cell viability was analyzed using a MTT assay, while flow cytometry was used to determine cell apoptosis. Wound healing and Transwell invasion assays were used to value cell migration and invasion, respectively. RNA immunoprecipitation assay, bioinformatics prediction and a dual luciferase reporter assay were used to analyze the target relationship. The RT-qPCR results showed that NEAT1 was highly expressed and miR-204-5p had decreased expression in LSCC tissues and cells compared with that in the normal tissue and the 16HBE-14o cell line, respectively. Knockdown of NEAT1 using small interfering (si) RNA and overexpressed miR-204-5p both effectively inhibited the proliferation, migration and invasion of LSCC cells. Besides, further experiments revealed that miR-204-5p was a target of NEAT1. At the same time, silenced miR-204-5p reversed the anti-tumor effects of si-NEAT1. In addition, SEMA4B was targeted by miR-204-5p in LSCC cells and upregulated SEMA4B weakened the antitumor effects of miR-204-5p in LSCC cells. NEAT1 regulated the expression of SEMA4B by targeting miR-204-5p in LSCC cells. Overall, NEAT1 promoted the proliferation and invasion of LSCC cells by regulating the miR-204-5p/SEMA4B axis.