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. Here, CD44 is linked to neoplasm.