Peritumoral TIGIT+CD20+ B cell infiltration indicates poor prognosis but favorable adjuvant chemotherapeutic response in gastric cancer

Objective: T cell immunoreceptor with immunoglobulin and ITIM domains (TIGIT) is a novel immunosuppressive molecule. This study aimed to investigate the expression of TIGIT on B cells and the function of TIGIT(+)CD20(+) B cells in gastric cancer (GC). Methods: Tumor tissue paraffin-embedded sections and clinicopathological data from 194 patients with GC were collected. Dual immunohistochemistry was performed to detect the expression of TIGIT on B cells. Multiplex immunofluorescence was used to initially explore the relationship between TIGIT(+)CD20(+) B cells and the exhaustion of CD8(+) T cells. Results: In GC, TIGIT(+)CD20(+) B cells were observed in intratumor, peritumor, and tertiary lymphoid structures (TLS). Patients with GC having high peritumoral TIGIT(+)CD20(+) B cells infiltration had inferior clinical outcomes and could benefit from adjuvant chemotherapy (ACT). In GC tissues, PD-1(+)CD8(+) T cells were more closer to TIGIT(+)CD20(+) B cells than to TIGIT(+)CD20(+) B cells. Conclusions: Peritumoral TIGIT(+)CD20(+)& nbsp;B cells infiltration was an independent prognostic predictor for patients with GC and a potential biomarker for ACT selection. TIGIT(+)CD20(+)& nbsp;B cells might affect the exhaustion of CD8(+) T cells in GC.

Automated summary

The study revealed that the infiltrated levels of TIGIT(+)CD20(+) B cells around tumors in gastric cancer patients were associated with clinical outcomes and could potentially impact the exhaustion of CD8(+) T cells.