document: Immunofluorescence microscopy. U87MG cells (3×104 per well in a 24-well plate) were treated with 1 μM VLP-based samples (Qβ VLPs, TrQβ@b-3WJsiEGFR siLUC, and TrQβ@b-3WJsiEGFR Let-7g) for 72 h. Then, the cells were washed with PBS (pH=7.4) and fixed with 75% ethanol. Then, the cells were incubated in blocking solution (10% bovine serum albumin (BSA), 0.3 M glycine and 0.1% Tween-20 in PBS buffer, pH=7.4) for 1 h. The blocked cells were incubated with EGFR antibody (ab8465, 1/1000 dilution)