4‐1BB Delineates Distinct Activation Status of Exhausted Tumor‐Infiltrating CD8+ T Cells in Hepatocellular Carcinoma

Abstract

Background and Aims Targeting costimulatory receptors with agonistic antibodies is a promising cancer immunotherapy option. We aimed to investigate costimulatory receptor expression, particularly 4‐1BB (CD137 or tumor necrosis factor receptor superfamily member 9), on tumor‐infiltrating CD8+ T cells (CD8+ tumor‐infiltrating lymphocytes [TILs]) and its association with distinct T‐cell activation features among exhausted CD8+ TILs in hepatocellular carcinoma (HCC). Approach and Results Tumor tissues, adjacent nontumor tissues, and peripheral blood were collected from HCC patients undergoing surgical resection (n = 79). Lymphocytes were isolated and used for multicolor flow cytometry, RNA‐sequencing, and in vitro functional restoration assays. Among the examined costimulatory receptors, 4‐1BB was most prominently expressed on CD8+ TILs. 4‐1BB expression was almost exclusively detected on CD8+ T cells in the tumor—especially on programmed death 1 (PD‐1)high cells and not PD‐1int and PD‐1neg cells. Compared to PD‐1int and 4‐1BBnegPD‐1high CD8+ TILs, 4‐1BBposPD‐1high CD8+ TILs exhibited higher levels of tumor reactivity and T‐cell activation markers and significant enrichment for T‐cell activation gene signatures. Per‐patient analysis revealed positive correlations between percentages of 4‐1BBpos cells among CD8+ TILs and levels of parameters of tumor reactivity and T‐cell activation. Among highly exhausted PD‐1high CD8+ TILs, 4‐1BBpos cells harbored higher proportions of cells with proliferative and reinvigoration potential. Our 4‐1BB–related gene signature predicted survival outcomes of HCC patients in the The Cancer Genome Atlas cohort. 4‐1BB agonistic antibodies enhanced the function of CD8+ TILs and further enhanced the anti‐PD‐1–mediated reinvigoration of CD8+ TILs, especially in cases showing high levels of T‐cell activation. Conclusion 4‐1BB expression on CD8+ TILs represents a distinct activation state among highly exhausted CD8+ T cells in HCC. 4‐1BB costimulation with agonistic antibodies may be a promising strategy for treating HCCs exhibiting prominent T‐cell activation.

Challenges of combination therapy with immune checkpoint inhibitors for hepatocellular carcinoma

“…As our understanding of the functional status of T cells, particularly exhausted T cell phenotypes, in tumour-infiltrating lymphocytes and peripheral blood from patients with HCC rapidly evolves, the predictive value of biomarkers from peripheral blood should be explored, as these biomarkers may overcome limitations of sample availability. [65][66][67] The availability of pre-and post-treatment tumour samples during ICI therapy is crucial for biomarker research in HCC. There is an ongoing clinical trial of pembrolizumab, in which serial tumour biopsies are planned at baseline and after 2 cycles of treatment (NCT03419481).…”

Tumor-infiltrating TNFRSF9 + CD8 + T cells define different subsets of clear cell renal cell carcinoma with prognosis and immunotherapeutic response

“…A study focused on hepatocellular carcinoma also revealed that TNFRSF9 was a distinct activation status marker of highly exhausted CD8 + T cells and TNFRSF9 + PD1 high CD8 + T cells exhibited higher activation markers than their TNFRSF9 − counterparts. 20 In ccRCC, higher TNFRSF9 + CD8 + T cells signature was significantly associated with higher shrinkage of tumor size and better response to ICB. This could be partly explained by the high expression of both PD-1 and effector phenotype markers in TNFRSF9 + CD8 + T cells.…”

“…18,19 Furthermore, a study on hepatocellular carcinoma has revealed that TNFRSF9 delineates a distinct activation status of exhausted tumor-infiltrating CD8 + T cells. 20 However, recent studies suggested a potential relationship between TNFRSF9 and T cells exhaustion, 8,21 which indicated the complicated role of TNFRSF9 in immune response. Also, the function of TNRSF9 + CD8 + T cells in ccRCC has not been well delineated.…”

Spatial Distribution and Prognostic Implications of Tumor-Infiltrating FoxP3- CD4+ T Cells in Biliary Tract Cancer

“…Although the immune heterogeneity among cancer patients is well known [22][23][24], the heterogeneity of immune subsets according to their location remains unclear. We aimed to Given that TIM3 and LAG3 are expressed on a highly activated and exhausted T cells [23], the abundance of LAG3 and TIM3 expression in the tumor margin suggests that this is the major site where the active engagement of T cells against tumor cells and resulting T cell exhaustion occur.…”