Expression of miR-155 in nasopharyngeal carcinoma and its effect on proliferation of human nasopharyngeal carcinoma cells

Objective:To investigate the expression of microRNA-155(miR-155)in nasopharyngeal carcinoma and its effect on the proliferation of nasopharyngeal carcinoma cells.Methods:Patients with nasopharyngeal carcinoma who underwent surgical resection in our hospital from September 2016 to September 2018 were selected.miR-155 was detected by real-time fluorescence quantitative PCR in nasopharyngeal carcinoma tissues,normal tissues and nasopharyngeal carcinoma cell lines(CEN1),which were resected in our hospital from September 2016 to September 2018.The expression of NP69 in normal nasopharyngeal epithelial cells was detected by silencing miR-155,and its effect on the proliferation of human nasopharyngeal carcinoma cells was detected.Results:The expression of miR-155 in nasopharyngeal carcinoma tissue and cell line CEN1 was significantly higher than that in normal tissues.The expression level of NP69 in nasopharyngeal epithelial cells was significantly higher than that in nasopharyngeal epithelial cells(t=8.560,P=0.000;t=42.386,P=0.000).The expression of miR-155 was correlated with TNM stage,pathological grade,extent of invasion and lymph node metastasis in nasopharyngeal carcinoma(P<0.05),but not with age and gender(P>0.05).The expression of miR-155 after transfection of miR-155-inhibitor was significantly lower than that of the control group and the blank control group(F=35.63,P=0.003).The growth rate of nasopharyngeal carcinoma cells silenced by miR-155 was significantly slower than that of control group and blank control group(P<0.05).Conclusion:The high expression of miR-155 in human nasopharyngeal carcinoma tissues and cells can inhibit the proliferation of nasopharyngeal carcinoma cells,and it is of great significance for the treatment of nasopharyngeal carcinoma.