The results showed that the messenger RNA (mRNA) expression of CASK was significantly upregulated in HCC tissues compared with normal liver tissues in The Cancer Genome Atlas (TCGA) (https://cancergenome.nih.gov/) (Figure 1A), and IHC staining performed by the human protein atlas (HPA) database (https://www.proteinatlas.org/) showed strongly positive CASK staining in HCC cancer tissue, but weakly positive staining in normal tissue (Figure 1B). Here, CASK is linked to cancer.