Fig. 5

Inhibition of Pdgfrβ and Pkcα activity promotes MET and suppresses Brca1-deficient tumor initiation. a p18^−/−;Brca1^MGKO tumor cells treated with PDGFR Inh III at 20 nM or Ro-31-8220 at 35 nM for 30 min were analyzed by western blot. b–d p18^−/−;Brca1^MGKO tumor cells were treated with PDGFR Inh III or Ro-31-8220 for 3 days. The number of viable cells was determined (b). The percentage of dead cells treated with PDGFR Inh III at 200 nM or Ro-31-8220 at 350 nM (c) and the morphology of cells treated with PDGFR Inh III at 20 nM or Ro-31-8220 at 35 nM (d) were also analyzed. Data in b and c are represented as the mean ± SD of triplicate experiments. The asterisk (*) denotes a significance from DMSO- and drug-treated cells. e, g Primary p18^−/−;Brca1^MGKO tumor cells were cultured to generate primary tumorsphere. 10⁴ cells dissociated from primary p18^−/−;Brca1^MGKO tumorspheres were treated with PDGFR Inh III at 20 nM and 200 nM (e) or Ro-31-8220 at 35 nM and 350 nM (g). Secondary tumorspheres formed after 6-day treatment were counted from triplicate experiments. Data are represented as the mean ± SD. f, h Cells dissociated from primary p18^−/−;Brca1^MGKO tumorspheres were treated with PDGFR Inh III at 20 nM or Ro-31-8220 at 35 nM. Six days after treatment, 1000 viable cells pretreated with DMSO, PDGFR Inh III (f), or Ro-31-8220 (h) were transplanted into MFP of NSG mice. Four weeks later, tumor volumes were determined. Data are represented as mean ± SD of four tumors in each group. i, j Tumors generated in f and h were analyzed by western blot (i) and IHC (j)