For instance, studies employing CRISPR-Cas9 to disrupt PD1 expression in CAR-T cells have shown enhanced cytotoxicity and reduced exhaustion in glioblastoma with anti-EGFRvIII CAR-T cells (113), increased cytokine production, improved tumor control, and relapse prevention in breast carcinoma with anti-MSLN CAR-T cells (114), and increased in vivo antitumor activity against HCC with anti-GPC3 CAR-T cells (115). This evidence concerns the gene MSLN and hepatocellular carcinoma.