Aim: To investigate the effect of microRNA-1 (miR-1) on tumor endothelial cells (TECs) of human hepatocellular carcinoma (HCC).
Methods: MiR-1 specific short hairpin RNA (shRNA) was synthesized and cloned into a recombinant lentiviral vector. TECs were then infected by the miRNA-1-shRNA recombinant lentivirus. TECs were divided into three groups: a control (CON) group consisting of normal TECs without lentiviral infection, a negative control (NC) group consisting of normal TECs infected with a negative control virus, and a micro-down (MD) group consisting of normal TECs infected with the miR-1-inhibition virus containing the target gene. Silencing of miR-1 expression was quantified via quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The proliferation of TECs was detected using MTT (Thiazolyl Blue Tetrazolium Bromide) assay; the observations were continued for 5 d, and the optical density value at 490 nm was detected every day. Apoptosis was detected via flow cytometry using Annexin V-APC single staining. The migration and invasion of TECs were detected using transwell assays.
Results: Lentiviral miR-1 shRNA was successfully transduced into TECs, and specifically silenced the expression of miR-1. The results of qRT-PCR showed that the expression of miR-1 was significantly decreased in the MD group (2(-ΔΔCt) = 0.57 ± 0.14) compared with the CON group (2(-ΔΔCt) = 1) and the NC group (2(-ΔΔCt) = 1.05 ± 0.13) (P < 0.01). The results of MTT assay showed that the cell proliferation was all significantly inhibited in the MD group in the 5 days compared with the CON and NC groups (P < 0.01). The results of flow cytometry showed that the apoptosis was significantly increased in the MD group (6.32% ± 0.33%) compared with the CON group (2.03% ± 0.30%) and the NC group (2.18% ± 0.15%) (P < 0.01). The ability of cell migration was significantly inhibited in the MD group (62.0 ± 5.48) compared with the CON group (99.8 ± 3.11) and the NC group (97.2 ± 3.70) (P < 0.01). The ability of invasion of TECs was also significantly inhibited in the MD group (29.8 ± 2.39) compared with the CON group (44.6 ± 3.36) and the NC group (44.4 ± 5.17) (P < 0.01).
Conclusion: MiR-1 might be a potential tumor activator. Inhibiting its expression could decrease proliferation, induce apoptosis, and inhibit the migration and invasion of TECs of human HCC.
Keywords: Hepatocellular carcinoma; MicroRNA-1; Short hairpin RNA; Tumor endothelial cells.