Abstract: Objective To investigate the effect of miR-125b-5p affecting energy metabolism and proliferation of laryngeal squamous cell carcinoma by down-regulating hexokinase 2. Methods LSCC cells were divided into miRNA-125b-5p transfection group and control group. The expression of miR-125b-5p in normal bronchial epithelial cell line and LSCC cell line was detected by RT-qPCR，proliferation and apoptosis of LSCC cells were detected by CCK-8 and flow cytometry，HK2 expression in LSCC after overexpression of miR-125b-5p was detected by Western blot，glucose consumption and lactic acid production by LSCC cells were determined by 3H-2DG and lactate colorimetry. Results RT-qPCR results showed that the expression of miR-125b-5p in LSCC cell line was lower than that in normal cell line（0.22±0.05 vs 0.68±0.03，t=7.025，P=0.001）. CCK-8 results showed that after 72 h and 96 h of transfection，the proliferation of LSCC cells in the miR-125b-5p transfection group was lower than that in the control group（P<0.05）. The results of flow cytometry showed that the apoptotic rate of LSCC cells in the miR-125b-5p transfection group was higher than that in the control group［（37.52±2.34）% vs （12.46±3.52）%，t=7.025，P<0.001）］. The colony-forming ability of LSCC cells in the miR-125b-5p transfection group was also lower than that in the control group（0.29±0.02 vs 1.02±0.03，t=5.689，P=0.005）. The results of luciferase reporter gene assay showed that the luciferase activity of the miR-125b?-5p transfection group was lower than that in the control group（0.32±0.03 vs 1.01±0.02，t=7.543，P=0.001）. The results of Western blot showed that the protein level of HK2 in LSCC cells over-expressed by miR-125b-5p in the miR-125b-5p transfection group was lower than that in the control group（0.12±0.02 vs 0.75±0.03，t=5.875，P=0.023）. The results of lactate colorimetriy assay showed that the glucose consumption of LSCC cells in the miR-125b-5p transfection group was lower than that in the control group［（3.85±0.86） dpm/mg vs （10.52±1.34） dpm/mg，t=6.118，P=0.005］. The production of lactic acid in LSCC cells transfected with miR-125b-5p was also lower than that in the control group［（4.23±1.36） dpm/mg vs （10.96±2.45） dpm/mg，t=5.907，P=0.002］. Conclusion miR-125b-5p may reduce the energy metabolism and proliferation of laryngeal squamous cell carcinoma by down-regulating HK2 expression, and induce apoptosis.

Key words: Laryngeal squamous cell carcinoma, miR-125b-5p, Hexokinase 2, Glycolysis, Proliferation