The Epstein-Barr Virus-Encoded MicroRNA MiR-BART9 Promotes Tumor Metastasis by Targeting E-Cadherin in Nasopharyngeal Carcinoma
Figure 2
Depletion of endogenous miR-BART9 suppresses the migration and invasiveness of EBV-positive NPC cells.
(A) LNA-modified anti-BART9 efficiently decreases the level of mature miR-BART9 in EBV-positive HK1-EBV and C666-1 cells. HK1-EBV and C666-1 cells were treated with a 12.5 nM concentration of an LNA-modified miR-BART9 antisense oligo (anti-BART9) or a scramble control (anti-Ctrl) for 48 hr. The expression level of miR-BART9 was determined via qPCR. (B) HK1-EBV cells were treated with anti-BART9 or anti-Ctrl for 24 hr and the plated for colony formation assays. Colony formation activity was determined via crystal violet staining after 11 days in culture. (C, D) Transwell migration assay (C) and Matrigel invasion assay (D) for HK1-EBV and C666-1 cells. Cells were treated with a 12.5 nM concentration of an LNA-modified miR-BART9 antisense oligo (anti-BART9) or a scramble control (anti-Ctrl) for 48 hr before the migration or invasion assay. Images of cells adhered to the lower surface of the filter insert from a representative experiment are shown. (Left panel). The numbers of migratory or invasive cells were quantified using image J and expressed as the fold change relative to the appropriate cell line (bar graphs). (E) Expression levels of LMP1, LMP2A and EBNA1 in HK1-EBV and C666-1 cells treated with a 12.5 nM concentration of an LNA-modified miR-BART9 antisense oligo (anti-BART9) or a scramble control (anti-Ctrl). Total RNA was collected 48 hr after transfection and mRNA levels were determined via qPCR. The data were normalized to cellular EEF1A1 levels and expressed as the fold change relative to the appropriate cell line. The bar graphs in (B), (C), (D), (E) show means ± SEM from three independent experiments and two-tailed Student's t-tests were performed (*, P<0.05; **, P<0.01; ***, P<0.001).
