Fig 2: TOP2A overexpression reverse the effect of miR-22-5p. (a, b) qRT-PCR and western blot analysis exposed the TOP2A mRNA and protein level of HCC cell lines (MHCC97L and BEL-7404) transfected with miR-Ctrl+vector, miR-22-5p mimics+vector, or miR-22-5p mimics+TOP2A. (c) Wound healing assays of HCC cells treated with miR-Ctrl+vector, miR-22-5p+vector, and miR-22-5p+TOP2A. (d) Transwell invasion assay of HCC cells treated with miR-Ctrl+vector, miR-22-5p+vector, and miR-22-5p+TOP2A. The bar graphs show the number of migrating and invasive cells after 24 h. Data are shown as mean ± SEM; ***P < 0.001, **P < 0.01, and *P < 0.05.

Fig 3: TOP2A activates cell cycle progression and promotes EMT process. (A, B) EdU assay performed in HCC cells with different levels of TOP2A expression. Scale bar 200μm. (C) G2/M checkpoint related proteins were detected by Western blot. (D) EMT related proteins were detected by Western blot. *P < 0.05, ** P < 0.01.

Fig 4: TOP2A enhances tumorigenesis and metastasis of HCC in vivo. (A) Images of nude mice bearing subcutaneous tumor xenografts derived either from sh-TOP2A or Negative Control cells and volume of tumors derived from sh-NC and sh-TOP2A Huh-7 cells. (B) IHC staining of Ki-67 in xenograft tumor tissue derived from sh-NC and sh-TOP2A Huh-7 cells, scale bar 100μm. (C) Representative images and HE images of lung metastatic nodules derived from sh-NC and sh-TOP2A Huh-7 cells, left panel, scale bar 200μm; right panel, scale bar 100μm. *P < 0.05, **P < 0.01.

Fig 5: TOP2A is upregulated in HCC and associated with poor prognosis. (A) mRNA expression level of TOP2A in HCC tissues and normal tissues from the TCGA database. (B) The relationship between TOP2A expression and overall survival of HCC patients according to the data obtained from TCGA-LIHC cohort. (C) RT-qPCR detected the mRNA expression of TOP2A in 45 paired HCC tissues and adjacent normal tissues. (D) Western blot detected the protein expression of TOP2A in 10 representative pairs of HCC tissues and adjacent nontumor tissues. (E) IHC staining scores of TOP2A expression in 90 paired HCC tissues and adjacent normal tissues. Representative images of different TOP2A expression levels are shown. up panel, scale bar 200μm; down panel, scale bar 100μm. (F) The relationship between TOP2A expression and overall survival of HCC patients according to the data obtained from TMA.