Fig. 1

Antagonism by IGF1 of Regorafenib-mediated growth inhibition of HCC cell Lines. a. Hep3B, PLC/PRF/5 and HepG2 cells were cultured in presence of Regorafenib 1–5 μM, IGF1 40 ng/ml, GSK1838705A 1 μM. MTT assay was assessed after 48 h (48 h). b. PLC/PRF/5 cells were cultured in presence of Regorafenib 5 μM and IGF1 40 ng/ml in different time conditions. In the first group (light gray) the cells previously treated with IGF1 for 48 h received Regorafenib for the following 24 h. In the second group (dark gray) the cells, previously treated with Regorafenib for 24 h, received IGF for the following 48 h. MTT assay was assessed after 72 h. c. PLC/PRF/5 cells were synchronized in the S phase of the cell cycle using thymidine 0.2 M (T0), after 6 h from block release (T1), the cells were processed with the Cell Cycle Kit and analyzed with Muse Cell Analyzer to evaluate the percentage of cells in G0/G1, S and G2/M phases. The panels represent an example of DNA content profile in different treatment conditions. The mean of three independent experiments was plotted in the relative graph, where the values are calculated as fold increase of the cells in G2/M at T1 respect to control cells at T0. The results of three independent experiments are expressed as means ± SD. ***p < 0.0001