Skip to main content
. 2013 Sep 23;288(44):31761–31771. doi: 10.1074/jbc.M113.514091

FIGURE 5.

FIGURE 5.

Functional silencing of Pgp in KBV1 (+Pgp) cells results in redistribution of DOX from LAMP2-stained lysosomes to DAPI-stained nuclei with concomitant toxicity. A, Western blot analysis showing transient silencing of Pgp in KBV1 (+Pgp) cells incubated with two types of Pgp siRNA (72 h, 37 °C) relative to KBV1 (+Pgp) cells treated with Scr siRNA. B, Pgp silencing in KBV1 (+Pgp) cells using a 72-h incubation with siRNA resulted in increased cytotoxicity (IC50/72 h) of DOX relative to KBV1 (+Pgp) cells treated with Scr siRNA. The Pgp inhibitor Ela (0.1 μm) increased cytotoxicity of DOX only in Scr siRNA-treated KBV1 (+Pgp) cells relative to Pgp siRNA-treated (Pgp-silenced) cells (72 h, 37 °C). C, siRNA silencing of Pgp (72 h, 37 °C) resulted in redistribution of DOX to nuclei, as indicated by DAPI staining, whereas Scr siRNA-treated KBV1 (+Pgp) cells resulted in accumulation of DOX in LAMP2-stained lysosomes (arrow). The results in A and C are typical from three experiments. The graph in B is mean ± S.D. ***, p < 0.001 versus control (i.e. drug alone). Scale bar = 50 μm.