Fructose-1, 6-bisphosphatase inhibits autophagy and proliferation in liver cancer cells

Abstract

Objective: To construct the recombinant adenoviral containing fructose 1, 6-biphosphatase 1 (FBP1), and to investigate whether FBP1 has effect on autophagy and proliferation in liver cancer cells (HepG2). Methods: FBP1 cDNA sequence was amplified by PCR and cloned in adenovirus vector pAdTrack-TO4, and then recombinant adenovirus plasmid pAdTrack-FBP1 was constructed. The recombinant adenovirus plasmid was transfected into HEK293 cells by Lipofectamine 3000. High-titer of recombinant adenovirus AdFBP1 was obtained by packaging and amplification. HepG2 cells were infected with recombinant adenovirus AdFBP1, and the Mock and AdGFP group were set at the same time. Western blot and confocal laser scanning microscopy were used to observe the effect of FBP1 on the level of autophagy in hepatocellular carcinoma cells, and the effect of FBP1on the proliferation was observed by MTS and colony formation assay. A t-test and one-way ANOVA were used to compare the mean between group. Results: A high-titer recombinant adenovirus FBP1 was successfully constructed. Western blot and confocal laser scanning microscopy showed that the level of autophagy in AdFBP1 group was significantly lower than that in AdGFP group. Western blot results showed that LC3-II protein expression level in AdGFP was 1.10 ± 0.10 and 0.30 ± 0.01 in AdFBP1 group, F = 90.36, P < 0.01. Confocal laser scanning microscopy analysis showed that the average number of autophages in AdGFP was 28.33 ± 1.53 and 12.33 ± 1.53 in AdFBP1group, F = 97.40, P < 0.01. In addition, the results of colony formation assay and MTS assay showed that the proliferation of liver cancer cells in the AdFBP1 group was significantly inhibited compared with the AdGFP group. The results of colony formation showed that the cell clones in the AdGFP group was 65.66 ± 2.57 and 34.00 ± 2.00 in AdFBP1 group, F = 141.50, P < 0.01. MTS results showed that the absorbance of AdGFP group at 96h was 39.13 ± 2.21 and 30.61 ± 3.33 in AdFBP1 group, F = 7.80, P < 0.05. Conclusion: FBP1 inhibited the autophagy and proliferation in liver cancer cells (HepG2).