In addition, in HCC and prostate cancers, the expression of CMTM5 is negatively associated with activation of the PI3K/AKT pathway (Figure 4)48,55, which is downstream of EGFR signaling, thus suggesting that CMTM5 may inhibit tumor growth and metastasis by targeting AKT48,55. Here, CMTM5 is linked to hepatocellular carcinoma.