Fig. 8

ATRA and Sorafenib synergistically inhibited PDX tumour growth via downregulating PAK1 activity. The tumours were presented in (A). The coefficient of drug interaction (CDI) calculated using tumour volume showed the synergistic effect of ATRA and Sorafenib in tumours with high PAK1 levels (B). The final tumour volume (C), tumour weight (D), and tumour growth curves (E and F) were presented. Tumour cell proliferation (G) was measured by the expression of PCNA in the PDXs as determined by IHC. The level of apoptosis in the PDXs (H) was measured by TUNEL assay. CT, control; Sora, Sorafenib; A + S, ATRA combined with Sorafenib; *p < 0.05, ***p < 0.001, compared with PAK1_Low CT, ^##p < 0.01, ^###p < 0.001, compared with PAK1_High CT, by t-test. Scale bar, 50 μm