B7-H6 (encoded by gene NCR3LG1) is a type I transmembrane protein of B7 family. It consists of two extracellular Ig-like domains (IgV and IgC), an α-helical transmembrane domain, and a C-terminal sequence homologous to group-specific antigen (GAG) proteins. This C-terminal sequence has various signaling motifs, including ITIM-, SH-2-, and SH-3-binding motifs. B7-H6 can bind its receptor NKp30 to exert anti-tumor effects by helping NK cells to recognize abnormal cells. B7-H6 is expressed in several tumor cell lines, both in vitro and in vivo, including esophageal squamous cell carcinoma, oral squamous cell carcinoma and breast cancer. but remains undetected in healthy cells thus far, and is therefore an excellent tumor marker. In recent years, B7-H6 expression has been reported to be upregulated in certain cancers and to be associated with tumor differentiation, stage and progression.