The study aims to investigate the possible mechanisms of microRNA-133a (miR-133a) targeting CD47 on cell proliferation, apoptosis, migration, and invasion in laryngeal carcinoma. Forty-two laryngeal carcinoma tissue specimens confirmed by pathological examination from laryngeal carcinoma patients as the case group were collected, and 20 chronic laryngitis tissues were gathered as the control group. The human laryngeal carcinoma cell line Hep-2 was marked as the miR-133a mimic, negative control (NC), miR-133a inhibitor, CD47-siRNA, miR-133a inhibitor + CD47-siRNA, and Mock groups. The expression of CD47 protein and miR-133a was detected by immunohistochemistry (IHC) and qRT-PCR. Dual luciferase assay system was used to determine the relationship between CD47 and miR-133a. Western blotting was used to measure the protein expression of CD47 and miR-133a. 5-Ethynyl-2'-deoxyuridine (EDU) method was used to detect the cell proliferation, and flow cytometry and Transwell were used to measure the cell apoptosis and migration and invasion, respectively. The miR-133a expression in laryngeal carcinoma tissues was significantly lower, while the CD47 expression was higher than that in chronic laryngitis tissues (both P < 0.01). The expression of miR-133a in the miR-133a mimic group was significantly higher than that in other groups (P < 0.05), and the messenger RNA (mRNA) and protein expression of CD47 in the CD47-siRNA and miR-133a mimic groups were significantly lower than those in the Mock and NC group (all P < 0.05), while the mRNA and protein expression of CD47 in the miR-133a inhibitor group were higher than in other groups (all P < 0.05). After transfection, the CD47-siRNA group had the strongest inhibitory activity, while the number of living cells in the miR-133a inhibitor group was significantly higher than that in other groups (all P < 0.05). The apoptosis rates in the miR-133a mimic and CD47-siRNA groups were significantly higher than that in the Mock and NC groups (all P < 0.05). The cell numbers that penetrated membrane in the miR-133a mimic and CD47-siRNA groups were less than in the Mock and NC groups (all P < 0.05). Upregulated miR-133a could inhibit proliferation, invasion, and migration and promote cell apoptosis in laryngeal carcinoma by targeting CD47. miR-133a targeting CD47 could be a new direction in the diagnosis and treatment of laryngeal carcinoma.
Keywords: Apoptosis; CD47; Invasion; Laryngeal carcinoma; MicroRNA-133a; Migration; Proliferation.