It is believed that sulfarotene blocks the activation of pro-tumorigenic signals downstream of RAS by upregulating retinoic acid receptor α (RARα) in hepatocellular carcinoma (HCC) TRCs and inhibiting the expression of SOS2 (Liceras-Boillos et al., 2018), a key mediator of the RAS signaling pathway (Sheffels et al., 2018; Schwartz et al., 2019; Wołoszynowska-Fraser et al., 2020) (Figure 1B). The gene discussed is SOS2; the disease is hepatocellular carcinoma.