To investigate the biological role of NPTX1 in HCC, we established stable NPTX1-overexpressing SMMC-7721 and MHCC-97h model cells (Figure 2A), which exhibit relatively low expression of NPTX1 among HCC cell lines based on our previous results (Figure 1D). This evidence concerns the gene NPTX1 and hepatocellular carcinoma.