Fig. 3

Triple ER, CDK4/6, and FGFR1 blockade reverts resistance in FGFR1-positive models. a Relative plating efficiency (left) and example of colony assays (right) of parental MCF7, T47-D, and FGFR1-amplified HCC1428 or their FGFR1-overexpressing or LTED-R variants in response to vehicle, palbociclib (MCF7 cell lines, 50 nM; T47-D and HCC1428 cell lines, 100 nM), fulvestrant (MCF7 cell lines, 0.5 nM; T47-D cell lines, 1.5 nM and HCC1428 cell lines, 5 nM), DCC, palbociclib plus fulvestrant, or palbociclib plus DCC. b In the same model as in a, the observed resistance against palbociclib + fulvestrant/DCC was reverted by adding the FGFR1 inhibitor rogaratinib (1 μM), as evidenced by the relative-plating efficiency data. Statistically significant difference between either vehicle and all combinations or double and triple combinations are shown. Error bars: standard error. ***P < 0.001; **P < 0.01; *P < 0.05