Effects of microRNA-21 overexpression on proliferation, apoptosis and aerobic glycolysis of pancreatic cancer cells

Abstract

Objective To investigate the effects of microRNA-21 (miR-21) on proliferation, apoptosis and aerobic clycolysis of pancreatic cancer cells and its possible mechanism. Methods Human pancreatic cancer cell SW1990 and normal pancreatic duct epithelial cell HPDE were taken as research objects. SW1990 cells were transfected and divided into miR-NC group (transfected with miR-NC) and miR-21-minic group (transfected with miR-21-minic). MTT and clone formation assay were used to detect cell proliferation ability. Flow cytometry was used to detect cell apoptosis. RT-qPCR was used to detect the mRNA expression levels of miR-21 and pyruvate kinase M2 (PKM2) in cells. Western blot was used to detect PKM2 protein level. The luciferase reporter assay was used to detect the targeting relationship between miR-21 and PKM2. Results The expression level of miR-21 in SW1990 cells was higher than that in HPDE cells (0.79±0.02 vs 0.23±0.02, t =34.290, P＜0.01), while the expression levels of PKM2 protein (0.41±0.03) and mRNA (0.62±0.02) in SW1990 cells were lower than those in HPDE cells (0.95±0.02, 1.13±0.03, t =25.940, 24.500, P＜0.01). At 72 and 96 hours, the cell proliferation ability and number of clones cell in the miR-21-minic group were significantly higher than those in the miR-NC group, while the number of apoptotic cells was lower than that in the miR-NC group (P＜0.05). The glucose consumption, and the content of lactate, hexokinase (HK) and lactate dehydrogenase (LDH) in miR-21-mimic group were significantly higher than those in miR-NC group ( t =5.992, 21.340, 5.643, 4.008, P＜0.05). The level of PKM2 protein in the miR-21 mic group was lower than that in the miR-NC group ( t =10.070, P＜0.01). There were a certain number of complementary base pairs between miR-21 and WT-3′ UTR-PKM2, and the cell luciferase activity of miR-21-minic+WT-PKM2 group was lower than that of the transfected miR-NC+WT-PKM2 group ( t =15.680, P＜0.01). Conclusion The overexpression of miR-21 in pancreatic cancer cells may promote the proliferation, aerobic glycolysis, and inhibit apoptosis of pancreatic cancer cells. The mechanism may be related to targeting PKM2.

Keywords

• microrna-21
• pyruvate kinase m2
• aerobic glycolysis
• pancreatic cancer
• apoptosis