Optimization of hinge domain enhances antitumor efficacy of globo H-targeted CAR-T cells in solid tumor models

Chimeric antigen receptor (CAR)-T cell therapy has shown remarkable efficacy in hematologic malignancies but remains limited in solid tumors. Globo-H, a glycosphingolipid overexpressed in epithelial cancers with restricted normal expression, is an attractive target. Globo-H-targeted vaccines and antibody-drug conjugates have demonstrated safety and antitumor activity. Although Globo-H CAR-T cells have been tested with different costimulatory domains, the impact of hinge configuration on CAR-T function remains largely unexplored. Here, we compare CD8α, CD28, and IgG4 hinges within a 4-1BB-based CAR framework. CD8α-hinge CAR-T cells exhibited superior activation, cytokine release, and cytotoxicity against Globo-H⁺ tumor cells in vitro. In xenograft models of renal and ovarian cancer, CD8α-hinge CAR-T cells significantly inhibited tumor growth, with enhanced expansion and infiltration into blood and tumor tissues. These findings support Globo-H as a viable target for CAR-T therapy in solid tumors and highlight the CD8α hinge as an optimal component for Globo-H CAR design.