Compared with the plasma RNase1 level of 0.52 μg mL−1 in mice with RNase1‐overexpressing HCC tumor reported in a previous study,[11e] the serum RNase1 level (1.37 μg mL−1) of mice in the 4T1‐R1 group indeed showed an abnormally high concentration (Figure S7, Supporting Information). This evidence concerns the gene RNASE1 and hepatocellular carcinoma.