B7-H3 is a type I transmembrane protein containing 316 amino acids with a molecular weight of ~45-66 kDa, which was first discovered in 2001 from a cDNA library derived from human DCs (109).The human B7-H3 gene is located on chromosome 15 and the mouse B7-H3 gene is localized on chromosome 9 (110).Upper B7-H3 shares 20-27% amino acid homology with other B7 family members (111).B7-H3 is abundantly expressed on the surface of tumor cells, with limited expression in normal cells, and is also involved in the formation of the tumor microenvironment (TME) (112). Here, CD80 is linked to neoplasm.