In our study, we analysed the mRNA expression level of RIPK4 in HCC through the UALCAN web resource (http://ualcan.path.uab.edu/cgi-bin/ualcan-res.pl) and found that the mRNA expression level of RIPK4 was significantly reduced in HCC tissues vs. normal tissues (p < 0.0001) (Figure 1A). The gene discussed is RIPK4; the disease is hepatocellular carcinoma.