CD274 and hepatocellular carcinoma: In triple-negative breast cancer (TNBC) and non-small cell lung cancer (NSCLC), CD44 positively regulates the expression of PD-L1 by binding to the regulatory region of the PD-L1 locus (45).CD105 is highly expressed in tumor cells and vascular endothelial cells around or inside tumors (including HCC), and it is an important marker for neovascularization in tumors.