Sorafenib regulates the activity of the transcription factors p53,22 hypoxia‐inducible factor 1‐alpha (HIF1α)23 and NRF2.7 To determine which transcription factor regulates S1R expression, target‐specific shRNAs against p53, HIF1α and NRF2 were transfected into HCC cells. Here, HIF1A is linked to hepatocellular carcinoma.