Moreover, liver metastasis was rare in all mice and there was no significant difference in tumor liver metastasis between these two groups at the end point of experiments; however, we found lung metastasis in all six mice with NC cell injection, but in mice with PCSK9-silencing cell injections, while lung metastasis of NC cell group was significantly more serious than that in PCSK9-silencing cell group (Fig. 8e). This evidence concerns the gene PCSK9 and neoplasm.