MicroRNA differential expression spectrum and microRNA-125a-5p inhibition of laryngeal cancer cell proliferation

The present study aimed to screen and analyze the differential expression spectrum of microRNA (miRNA) between laryngeal cancer tissue and surrounding normal laryngeal mucosa in order to provide an indication for further study to determine the role of miRNA in the initiation and development of laryngeal cancer. A total of 42 pairs of specimens of laryngeal carcinoma tissues and adjacent normal laryngeal mucosa were collected. A total of 10 pairs of specimens were randomly selected for miRNA microarray gene chip analysis, and the remaining 32 pairs of specimens were used for reverse transcription-quantitative polymerase chain reaction (RT-qPCR) verification to identify miRNA that were differentially expressed in laryngeal cancer tissues. Methylthiazolyldiphenyl-tetrazolium bromide and clone formation assays were utilized to elucidate the physiological relevance of the miRNA miR-125a-5p on the proliferation of laryngeal cancer human epithelial type 2 (Hep2) cells. Results demonstrated that the expression levels of six miRNA were significantly downregulated in laryngeal carcinoma tissue, as identified by gene chip analysis and RT-qPCR (P<0.05). The six miRNA included let-7f-5p, miR-10a-5p, miR-125a-5p, miR-144-3p, miR-195-5p and miR-203. Compared with the control group, the proliferative ability of laryngeal cancer Hep2 cells was inhibited in a transfected miR-125a-mimics group. In contrast, proliferation was promoted in a transfected miR-125a-inhibitor group. In conclusion, the results of gene chip analysis were consistent with that of RT-qPCR. Results demonstrated that miRNA in laryngeal cancer and normal laryngeal mucosa exhibited evident differential expression, which may contribute to the laryngeal cancer incidence and invasion. miR-125a was able to inhibit the proliferation of Hep2 laryngeal cancer cells and, therefore, may serve as a novel target for laryngeal cancer biological therapy.