*4.3. Antisense LNA GapmeR-Mediated Knockdown*

Transfections in both cell lines were conducted using a final concentration of 150 nM in a ratio of 3:1 with the FuGENE HD-Transfection reagent (E2311, Promega Corporation, Madison, WI, USA) in accordance with the producers' instructions and as described previously [7,31]. DONSON GapmeR sequence: 5- -A\*C\*C\*A\*G\*T\*C\*A\*C\*T\*C\*A\*T\*T\*A\*A-3- . Non-targeting negative control GapmeR sequence: 5- -\*C\*G\*T\*A\*\*G\*T\*C\*G\*A\*G\*G\*A\*A\*G\*T\*A-3- .

## *4.4. Immunocytochemistry*

Briefly, 72 h post-transfection, PC-3 cells were harvested and transferred into Cellmatrix (Type I-A) (Fujifilm Wako Chemicals, Osaka, Japan). Subsequently, cells were fixed in 4% paraformaldehyde for 24 h and embedded into paraffin. Afterward, DONSON staining was performed as described in Section 4.2.
