2.4. RNA pull-down assay

The pull-down assay was applied as previously described. Briefly, the biotinylated miR-361-3p probe and oligo probe (GenePharma, China) were incubated with M-280 Streptavidin magnetic beads (cat. no. 60210; Invitrogen, USA) for 2 h at room temperature to generate probe-coated beads. Then, Du145 cells (10⁷ cells) were harvested, lysed, sonicated, and incubated with probe-coated beads at 4°C overnight. After washing, the RNA complexes bound to the beads were eluted and extracted with RNA isolation kit (cat. no. AM1920; Invitrogen, USA) and analyzed by quantitative real-time PCR (qRT-PCR) assay.