Objective:To investigate the effect of ribonucleotide reductase regulatory subunit M2 (RRM2) on the malignant biological behavior and aerobic glycolysis of gastric cancer cells by regulating cyclin-dependent kinase (CDK) 1.Methods:Human gastric cancer MKN-45 cells were divided into si-NC group (transfected with blank fragment) , CoCl 2+si-NC group (hypoxia control transfected with blank fragment) , CoCl 2+si-RRM2 group (hypoxia with RRM2 silencing) , CoCl 2+si-RRM2+pcDNA3.1 NC group (hypoxia with RRM2 silencing and blank vector) and CoCl 2+si-RRM2+pcDNA3.1 CDK1 group (hypoxia with RRM2 silencing and CDK1 overexpression) . The mRNA relative expression levels of RRM2 and CDK1 were analyzed by real time fluorescent quantitative reverse transcription PCR. Co-immunoprecipitation (CoIP) was used to analyze the interaction between RRM2 and CDK1 protein. MTT assay was used to analyze the proliferation activity of cells. The cell migration distance was detected by cell scratch assay. Cell apoptosis was detected by flow cytometry. Adenosine triphosphate (ATP) and glucose kit were used to detect ATP production and glucose consumption. The protein expressions of ENO1, RRM2, HK2, PKM2, GLUT1 and p-CDK1/CDK1 were detected by Western blotting. Results:Real time fluorescent quantitative reverse transcription PCR results showed that the relative expression levels of CDK1 mRNA in si-NC group, CoCl 2+si-NC group and CoCl 2+si-RRM2 group were 1.01±0.15, 1.30±0.06 and 0.51±0.18, and the relative expression levels of RRM2 mRNA were 1.03±0.32, 1.59±0.28 and 0.44±0.17, respectively, and there were statistically significant differences ( F=25.52, P=0.001; F=14.47, P=0.005) . The mRNA expressions of RRM2 and CDK1 in CoCl 2+si-NC group were higher than those in si-NC group. Compared with the si-NC group and the CoCl 2+si-NC group, the mRNA expressions of RRM2 and CDK1 were lower in the CoCl 2+si-RRM2 group (all P<0.05) . CoIP results showed that there was interaction between RRM2 and CDK1. MTT assay, cell scratch assay and flow cytometry showed that the cell proliferation activity of si-NC group, CoCl 2+si-NC group, CoCl 2+si-RRM2 group, CoCl 2+si-RRM2+pcDNA3.1 NC group and CoCl 2+si-RRM2+pcDNA3.1 CDK1 group were 1.04±0.01, 1.18±0.04, 0.84±0.03, 0.81±0.03 and 0.93±0.05, respectively. The cell migration distances were (301.83±2.75) , (369.67±0.76) , (176.50±6.38) , (175.83±3.69) , (254.17±1.61) μm, respectively. The apoptosis rates were 8.05%±0.21%, 5.75%± 0.20%, 28.28%±0.04%, 30.18%±1.51% and 17.79%±0.22%, respectively, all with statistically significant differences ( F=73.82, P<0.001; F=1 600.01, P<0.001; F=787.15, P<0.001) . Compared with the si-NC group and CoCl 2+si-NC group, the proliferation and migration ability of cells in the CoCl 2+si-RRM2 group, CoCl 2+si-RRM2+pcDNA3.1 NC group and CoCl 2+si-RRM2+pcDNA3.1 CDK1 group were weaker, and the apoptosis rates were higher (all P<0.05) . Compared with the CoCl 2+si-RRM2+pcDNA3.1 NC group, the proliferation and migration ability of cells in the CoCl 2+si-RRM2+pcDNA3.1 CDK1 group were stronger, and the apoptosis rate was lower (all P<0.05) . The results of ATP and glucose detection showed that there were statistically significant differences in the amount of ATP production and glucose consumption among the above five groups ( F=12.53, P<0.001; F=19.21, P<0.001) . Compared with the si-NC group, the glucose consumption of cells was lower in the CoCl 2+si-RRM2+pcDNA3.1 CDK1 group ( P<0.05) . Compared with the CoCl 2+si-NC group, the ATP production and glucose consumption of cells in the CoCl 2+si-RRM2+pcDNA3.1 CDK1 group were lower (both P<0.05) . Compared with the CoCl 2+si-RRM2+pcDNA3.1 NC group, the ATP production and glucose consumption of the CoCl 2+si-RRM2+pcDNA3.1 CDK1 group were higher (both P<0.05) . Western blotting showed that there were statistically significant differences in the protein expressions of ENO1, RRM2, HK2, PKM2, GLUT1, and p-CDK1/CDK1 among the above five groups (all P<0.001) . Compared with the si-NC group and the CoCl 2+si-NC group, the protein expressions of ENO1, RRM2, HK2, PKM2, GLUT1 and p-CDK1/CDK1 in the CoCl 2+si-RRM2+pcDNA3.1 CDK1 group were lower (all P<0.05) . Compared with the CoCl 2+si-RRM2+pcDNA3.1 NC group, the protein expressions of ENO1, RRM2, PKM2, GLUT1 and p-CDK1/CDK1 in the CoCl 2+si-RRM2+pcDNA3.1 CDK1 group were higher (all P<0.05) . Conclusions:Silencing RRM2 can inhibit the malignant biological behavior of gastric cancer cells and the occurrence of aerobic glycolysis by regulating CDK1.

Objective:To investigate the regulatory effect of long non-coding RNA (lncRNA) FTX on gastric cancer cell proliferation through miR-22-3p/NOD-like receptor protein 3 (NLRP3) inflammasome pathway.Methods:The gastric cancer cell line NCI-N87 were divided into blank control group, si-FTX-NC group, si-FTX group, si-FTX+miR-22-3p inhibitor-NC group and si-FTX+miR-22-3p inhibitor group. Quantitative real-time fluorescent PCR was performed to analyze the expression levels of lncRNA FTX and miR-22-3p, clone formation assay was performed to analyze the proliferation ability of NCI-N87 cells, western blotting was performed to analyze the expressions of NLRP3 inflammasome pathway proteins, and dual-luciferase reporter assay was performed to analyze the targeting relationship between lncRNA FTX and miR-22-3p.Results:The relative expressions of lncRNA FTX in the blank control group, si-FTX-NC group, si-FTX group, si-FTX+miR-22-3p inhibitor-NC group and si-FTX+miR-22-3p inhibitor group were 1.03±0.09, 1.01±0.15, 0.42±0.08, 0.45±0.06 and 0.46±0.13 respectively, with a statistically significant difference ( F=52.19, P<0.001). The relative expressions of miR-22-3p were 1.04±0.12, 0.97±0.08, 2.26±0.15, 2.23±0.13 and 1.15±0.11 respectively, with a statistically significant difference ( F=178.53, P<0.001). Compared with the blank control group and si-FTX-NC group, the relative expressions of lncRNA FTX in the si-FTX group, si-FTX+miR-22-3p inhibitor-NC group and si-FTX+miR-22-3p inhibitor group decreased (all P<0.001). Compared with the blank control group, si-FTX-NC group and si-FTX+miR-22-3p inhibitor group, the relative expressions of miR-22-3p in the si-FTX group and si-FTX+miR-22-3p inhibitor-NC group increased (all P<0.001). The clones of the five groups were 115.50±7.25, 112.33±8.46, 54.83±5.17, 56.17±6.32 and 85.67±9.43, with a statistically significant difference ( F=91.67, P<0.001). The levels of NLRP3 protein in the five groups were 1.84±0.17, 1.86±0.12, 0.95±0.09, 0.97±0.11 and 1.28±0.19, with a statistically significant difference ( F=60.62, P<0.001). Compared with the blank control group and si-FTX-NC group, the number of clones and the level of NLRP3 protein of the si-FTX group, si-FTX+miR-22-3p inhibitor-NC group and si-FTX+miR-22-3p inhibitor group decreased (all P<0.05). Compared with the si-FTX+miR-22-3p inhibitor group, the number of clones and the level of NLRP3 protein in the si-FTX group and si-FTX+miR-22-3p inhibitor-NC group decreased (all P<0.05). The dual-luciferase reporter assay found that miR-22-3p was the target gene of lncRNA FTX. Conclusion:Silencing the expression of lncRNA FTX can inhibit the proliferation of gastric cancer cells, and the mechanism may be related to the regulation of lncRNA FTX on the miR-22-3p/NLRP3 inflammasome pathway.