CD276 Gene (B7-H3): Function, Expression, and Clinical Significance | Biomedical Resource

CD276, also known as B7-H3, is a type I transmembrane glycoprotein belonging to the B7 family of immune checkpoint molecules. It is encoded by the CD276 gene located on chromosome 15q24.1. CD276 is involved in the regulation of T-cell-mediated immune responses, acting as both a co-stimulatory and co-inhibitory molecule depending on the context. It is overexpressed in a wide range of human cancers, where it promotes tumor immune evasion, metastasis, and resistance to therapy, making it an attractive target for cancer immunotherapy. CD276 expression is also found in normal tissues at low levels, but its upregulation in tumors correlates with poor prognosis in several cancer types.

Tissue Expression

Cell Line Expression

Hotspot Mutations

Mutation functional classification

• T cell receptor signaling pathway

• PD-1/PD-L1 checkpoint pathway (related)

• Cancer immune evasion pathway

• B7 family signaling

The CD276 protein (B7-H3) is a 316-amino acid type I transmembrane protein with an extracellular domain containing immunoglobulin-like V and C2 domains. It is expressed on various immune cells and tumor cells. CD276 interacts with putative receptors on T cells and NK cells, modulating their activity. In tumors, CD276 is often overexpressed, contributing to an immunosuppressive tumor microenvironment. Its structure includes multiple isoforms due to alternative splicing, with the 4Ig-B7-H3 isoform being predominant in humans. The protein is glycosylated and can be cleaved to a soluble form (sB7-H3) that may serve as a biomarker. CD276 is a focus of therapeutic development, including monoclonal antibodies and CAR-T cell therapies.