Fig. 3

PI3K-C2β downregulation potentiates the effect of docetaxel on cell numbers. a PC3 cells and the indicated stable cell lines were incubated with the indicated concentrations of docetaxel for 72 h before cell counting. For each cell line data are expressed as percentage of cells treated with DMSO (control) and are means ± s.e.m. of: n = 3–10 (PC3), n = 3–4 (sh scrambled clone 3), n = 3 (sh scrambled clone 4, sh PI3K-C2β clone 4), and n = 6–8 (sh PI3K-C2β clone 3) independent experiments performed in duplicate. No statistical significant difference was detected in the number of cells treated with DMSO between the different cell lines. For both sh PI3K-C2β clones: *p < 0.05, **p < 0.01 vs corresponding PC3; ^#p < 0.05 vs corresponding sh scrambled (3); ^$p < 0.05, ^$$p < 0.01 vs corresponding sh scrambled (4) (two tailed, unpaired t-Test with Welch’s correction). b PC3 cells were transfected with the indicated siRNAs. After 24 h, cells were incubated in complete media supplemented with 0.5 nM docetaxel or DMSO for further 72 h. The number of cells was assessed by cell counting. Data are expressed as percentage of cells transfected with transfection reagent and treated with DMSO (control) and are means ± s.e.m. of n = 6 independent experiments performed in duplicate. ^###p < 0.001, ^####p < 0.0001 vs corresponding oligo; ^$$$p < 0.001, ^$$$$p < 0.0001 vs corresponding si control (two tailed, unpaired t-Test with Welch’s correction). c HeLa cells were transfected with the indicated siRNAs. After 24 h, cells were incubated in complete media supplemented with the indicated concentrations of docetaxel or DMSO for further 72 h. Data indicate number of cells assessed by cell counting and are expressed as percentage of cells transfected with si control and treated with DMSO (control). Data are means ± s.e.m. of n = 4–5 independent experiments performed in duplicate. *p<0.05 **p < 0.01, ***p < 0.001, ****p < 0.0001 vs corresponding si control; ^#p < 0.05, ^###p < 0.001 vs si control/DMSO; ^$$p < 0.01, ^$$$$p < 0.0001 vs si PI3K-C2β (2)/DMSO; ^££p < 0.01, ^£££p < 0.0001 vs si PI3K-C2β (3)/DMSO (two tailed, unpaired t-Test with Welch’s correction). Downregulation of the enzyme at the indicated times was confirmed by Western blotting. Tubulin and GAPDH were used as loading control