标题：B7-H3 in tumors: friend or foe for tumor immunity?
作者：Li, Gen; Quan, Yanchun; Che, Fengyuan; Wang, Lijuan
作者机构：[Li, Gen] Weifang Med Univ, Dept Neurol, Clin Med Coll, 7166 Baotong West St, Weifang City 261053, Shandong, Peoples R China.; [Li, Gen; Quan, Yanch 更多
通讯作者：Che, FY;Wang, LJ;Che, FY;Wang, LJ
通讯作者地址：[Che, FY; Wang, LJ]Shandong Univ, Linyi Peoples Hosp, Cent Lab, NB27,Eastern Part Jiefang Rd, Linyi 276000, Shandong, Peoples R China;[Che, FY]Shandon 更多
来源：CANCER CHEMOTHERAPY AND PHARMACOLOGY
关键词：B7-H3; Expression; Co-stimulatory; Co-inhibitory; Tumor immunity; Cancer; immunotherapy
摘要：B7-H3 is a type I transmembrane co-stimulatory molecule of the B7 family. B7-H3 mRNA is widely distributed in most tissues; however, B7-H3 protein is not constitutively expressed. Few molecules have been shown to mediate the regulation of B7-H3 expression, and their regulatory mechanisms remain unexplored. Recently, TREM-like transcript 2 (TLT-2) has been identified as a potential receptor of B7-H3. However, TLT-2 may not be the only receptor of B7-H3, as B7-H3 has many contradictory roles. As a co-stimulatory molecule, B7-H3 increases the proliferation of both CD4+ and CD8+ T-cells and enhances cytotoxic T-cell activity. However, greatly increased T-cell proliferation and IL-2 levels have been observed in the absence of B7-H3. Thus far, it has been shown that various tumors test positive for B7-H3 expression and that B7-H3 levels correlate with tumor growth, invasion, metastasis, malignant stage, and recurrence rate. Furthermore, transfection of cells with a B7-H3 plasmid and treatment with monoclonal antibodies to block B7-H3 are the main immunotherapeutic strategies for cancer treatment. Several groups have generated anti-B7-H3 antibodies and observed tumor growth suppression in vitro and in vivo. Therefore, it is likely that B7-H3 plays an important role in cancer diagnosis and treatment, aside from its role as a co-stimulatory molecule.