Effects of AQP3 silencing on cell volume changes and inhibition of cell growth induced by nucleoside analogs. Non-transfected (white), negative control siRNA (dashed) or AQP3-siRNA (black) transfected MCF7 or HT29 cells were treated for 90 min with 250 μM 5′-DFUR or 100 nM gemcitabine for MCF7 and 50 μM gemcitabine for HT29. After 48 hours cells were trypsinized and diameter was measured as an estimation of volume changes (a) along with number of cells (b) using a cell counter. Cell viability is calculated as a percentage basis in relation to untreated cells as a reference. Results are presented as means ± SE of six independent experiments measured in triplicate. Statistical significance was assessed with the paired Student’s t test (* p < 0.05; ** p < 0.01; *** p < 0.001).