BRAF and hepatocellular carcinoma: To determine whether RAF1 ablation plays a role in HCCs as suggested by the analysis of these data, we generated an isogenic HCC cell line in which RAF1 can be knocked down by the expression of a shRNA controlled by a doxycycline-inducible promoter, without affecting the expression of A- or BRAF (Hep3B RAF1 KD; Fig. 1b).